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  Subjects -> ELECTRONICS (Total: 207 journals)
Showing 1 - 200 of 277 Journals sorted by number of followers
IEEE Transactions on Aerospace and Electronic Systems     Hybrid Journal   (Followers: 313)
Control Systems     Hybrid Journal   (Followers: 253)
IEEE Transactions on Geoscience and Remote Sensing     Hybrid Journal   (Followers: 201)
Journal of Guidance, Control, and Dynamics     Hybrid Journal   (Followers: 197)
Electronics     Open Access   (Followers: 138)
Advances in Electronics     Open Access   (Followers: 133)
Electronic Design     Partially Free   (Followers: 129)
Electronics For You     Partially Free   (Followers: 128)
IEEE Antennas and Propagation Magazine     Hybrid Journal   (Followers: 120)
IEEE Power Electronics Magazine     Full-text available via subscription   (Followers: 91)
IEEE Transactions on Power Electronics     Hybrid Journal   (Followers: 89)
IEEE Antennas and Wireless Propagation Letters     Hybrid Journal   (Followers: 88)
IEEE Transactions on Software Engineering     Hybrid Journal   (Followers: 84)
IEEE Transactions on Industrial Electronics     Hybrid Journal   (Followers: 84)
IEEE Transactions on Antennas and Propagation     Full-text available via subscription   (Followers: 81)
IET Power Electronics     Open Access   (Followers: 70)
IEEE Transactions on Automatic Control     Hybrid Journal   (Followers: 67)
Selected Topics in Applied Earth Observations and Remote Sensing, IEEE Journal of     Hybrid Journal   (Followers: 63)
IEEE Embedded Systems Letters     Hybrid Journal   (Followers: 62)
IEEE Transactions on Industry Applications     Hybrid Journal   (Followers: 58)
IEEE Journal of Emerging and Selected Topics in Power Electronics     Hybrid Journal   (Followers: 53)
Canadian Journal of Remote Sensing     Full-text available via subscription   (Followers: 53)
Advances in Power Electronics     Open Access   (Followers: 49)
IEEE Nanotechnology Magazine     Hybrid Journal   (Followers: 45)
IEEE Transactions on Consumer Electronics     Hybrid Journal   (Followers: 45)
Journal of Electrical and Electronics Engineering Research     Open Access   (Followers: 41)
IEEE Transactions on Biomedical Engineering     Hybrid Journal   (Followers: 35)
IEEE Transactions on Circuits and Systems for Video Technology     Hybrid Journal   (Followers: 34)
IET Microwaves, Antennas & Propagation     Open Access   (Followers: 34)
Journal of Physics B: Atomic, Molecular and Optical Physics     Hybrid Journal   (Followers: 32)
American Journal of Electrical and Electronic Engineering     Open Access   (Followers: 30)
IEEE Transactions on Information Theory     Hybrid Journal   (Followers: 28)
Electronics Letters     Open Access   (Followers: 28)
Bell Labs Technical Journal     Hybrid Journal   (Followers: 27)
Microelectronics and Solid State Electronics     Open Access   (Followers: 27)
International Journal of Power Electronics     Hybrid Journal   (Followers: 24)
International Journal of Aerospace Innovations     Full-text available via subscription   (Followers: 24)
Journal of Sensors     Open Access   (Followers: 23)
International Journal of Image, Graphics and Signal Processing     Open Access   (Followers: 22)
IEEE Reviews in Biomedical Engineering     Hybrid Journal   (Followers: 20)
IEEE/OSA Journal of Optical Communications and Networking     Hybrid Journal   (Followers: 19)
IEEE Transactions on Electron Devices     Hybrid Journal   (Followers: 18)
Journal of Artificial Intelligence     Open Access   (Followers: 18)
Journal of Power Electronics & Power Systems     Full-text available via subscription   (Followers: 17)
IET Wireless Sensor Systems     Open Access   (Followers: 17)
Circuits and Systems     Open Access   (Followers: 16)
Archives of Electrical Engineering     Open Access   (Followers: 15)
International Journal of Control     Hybrid Journal   (Followers: 14)
IEEE Transactions on Signal and Information Processing over Networks     Hybrid Journal   (Followers: 14)
International Journal of Advanced Research in Computer Science and Electronics Engineering     Open Access   (Followers: 14)
IEEE Women in Engineering Magazine     Hybrid Journal   (Followers: 13)
Advances in Microelectronic Engineering     Open Access   (Followers: 13)
IEEE Solid-State Circuits Magazine     Hybrid Journal   (Followers: 13)
Machine Learning with Applications     Full-text available via subscription   (Followers: 12)
Intelligent Transportation Systems Magazine, IEEE     Full-text available via subscription   (Followers: 12)
IEEE Transactions on Broadcasting     Hybrid Journal   (Followers: 12)
IEEE Transactions on Learning Technologies     Full-text available via subscription   (Followers: 12)
IEICE - Transactions on Electronics     Full-text available via subscription   (Followers: 11)
International Journal of Sensors, Wireless Communications and Control     Hybrid Journal   (Followers: 11)
International Journal of Microwave and Wireless Technologies     Hybrid Journal   (Followers: 11)
International Journal of Advanced Electronics and Communication Systems     Open Access   (Followers: 11)
Journal of Low Power Electronics     Full-text available via subscription   (Followers: 11)
Open Journal of Antennas and Propagation     Open Access   (Followers: 10)
Solid-State Electronics     Hybrid Journal   (Followers: 10)
International Journal of Advances in Telecommunications, Electrotechnics, Signals and Systems     Open Access   (Followers: 10)
IETE Journal of Research     Open Access   (Followers: 10)
Batteries     Open Access   (Followers: 9)
Electronics and Communications in Japan     Hybrid Journal   (Followers: 9)
International Journal of Wireless and Microwave Technologies     Open Access   (Followers: 9)
IETE Technical Review     Open Access   (Followers: 9)
Nature Electronics     Hybrid Journal   (Followers: 9)
Journal of Signal and Information Processing     Open Access   (Followers: 9)
APSIPA Transactions on Signal and Information Processing     Open Access   (Followers: 8)
IEEE Journal of the Electron Devices Society     Open Access   (Followers: 8)
International Journal of Electronics and Telecommunications     Open Access   (Followers: 8)
Journal of Electromagnetic Waves and Applications     Hybrid Journal   (Followers: 8)
China Communications     Full-text available via subscription   (Followers: 8)
Superconductivity     Full-text available via subscription   (Followers: 8)
IEEE Transactions on Autonomous Mental Development     Hybrid Journal   (Followers: 8)
Journal of Low Power Electronics and Applications     Open Access   (Followers: 8)
International Journal of Antennas and Propagation     Open Access   (Followers: 8)
Journal of Electronic Design Technology     Full-text available via subscription   (Followers: 8)
Advances in Electrical and Electronic Engineering     Open Access   (Followers: 8)
Universal Journal of Electrical and Electronic Engineering     Open Access   (Followers: 7)
Power Electronic Devices and Components     Open Access   (Followers: 7)
Foundations and Trends® in Signal Processing     Full-text available via subscription   (Followers: 7)
Nanotechnology, Science and Applications     Open Access   (Followers: 7)
IEEE Magnetics Letters     Hybrid Journal   (Followers: 7)
Progress in Quantum Electronics     Full-text available via subscription   (Followers: 7)
Foundations and Trends® in Communications and Information Theory     Full-text available via subscription   (Followers: 6)
Metrology and Measurement Systems     Open Access   (Followers: 6)
Advances in Biosensors and Bioelectronics     Open Access   (Followers: 6)
International Journal of Systems, Control and Communications     Hybrid Journal   (Followers: 6)
Kinetik : Game Technology, Information System, Computer Network, Computing, Electronics, and Control     Open Access   (Followers: 6)
International Journal of Electronics     Hybrid Journal   (Followers: 6)
IEICE - Transactions on Information and Systems     Full-text available via subscription   (Followers: 6)
Research & Reviews : Journal of Embedded System & Applications     Full-text available via subscription   (Followers: 6)
Journal of Power Electronics     Hybrid Journal   (Followers: 6)
Annals of Telecommunications     Hybrid Journal   (Followers: 6)
Electronic Markets     Hybrid Journal   (Followers: 6)
Energy Storage Materials     Full-text available via subscription   (Followers: 6)
IEEE Transactions on Services Computing     Hybrid Journal   (Followers: 5)
International Journal of Computational Vision and Robotics     Hybrid Journal   (Followers: 5)
Journal of Optoelectronics Engineering     Open Access   (Followers: 5)
Journal of Electromagnetic Analysis and Applications     Open Access   (Followers: 5)
Journal of Field Robotics     Hybrid Journal   (Followers: 5)
Journal of Electronics (China)     Hybrid Journal   (Followers: 5)
Batteries & Supercaps     Hybrid Journal   (Followers: 5)
IEEE Pulse     Hybrid Journal   (Followers: 5)
Journal of Microelectronics and Electronic Packaging     Hybrid Journal   (Followers: 4)
Networks: an International Journal     Hybrid Journal   (Followers: 4)
EPE Journal : European Power Electronics and Drives     Hybrid Journal   (Followers: 4)
Advanced Materials Technologies     Hybrid Journal   (Followers: 4)
Frontiers in Electronics     Open Access   (Followers: 4)
Wireless and Mobile Technologies     Open Access   (Followers: 4)
Synthesis Lectures on Power Electronics     Full-text available via subscription   (Followers: 4)
Journal of Energy Storage     Full-text available via subscription   (Followers: 4)
IEEE Transactions on Haptics     Hybrid Journal   (Followers: 4)
Journal of Electrical Engineering & Electronic Technology     Hybrid Journal   (Followers: 4)
Journal of Circuits, Systems, and Computers     Hybrid Journal   (Followers: 4)
International Journal of Review in Electronics & Communication Engineering     Open Access   (Followers: 4)
Electronic Materials Letters     Hybrid Journal   (Followers: 4)
Journal of Biosensors & Bioelectronics     Open Access   (Followers: 4)
Biomedical Instrumentation & Technology     Hybrid Journal   (Followers: 4)
IJEIS (Indonesian Journal of Electronics and Instrumentation Systems)     Open Access   (Followers: 3)
Informatik-Spektrum     Hybrid Journal   (Followers: 3)
IEEE Journal on Exploratory Solid-State Computational Devices and Circuits     Hybrid Journal   (Followers: 3)
International Journal of Numerical Modelling: Electronic Networks, Devices and Fields     Hybrid Journal   (Followers: 3)
Advancing Microelectronics     Hybrid Journal   (Followers: 3)
International Journal of Applied Electronics in Physics & Robotics     Open Access   (Followers: 3)
IETE Journal of Education     Open Access   (Followers: 3)
Superconductor Science and Technology     Hybrid Journal   (Followers: 3)
Sensors International     Open Access   (Followers: 3)
e-Prime : Advances in Electrical Engineering, Electronics and Energy     Open Access   (Followers: 3)
EPJ Quantum Technology     Open Access   (Followers: 3)
Frontiers of Optoelectronics     Hybrid Journal   (Followers: 3)
Transactions on Electrical and Electronic Materials     Hybrid Journal   (Followers: 2)
ACS Applied Electronic Materials     Open Access   (Followers: 2)
IET Smart Grid     Open Access   (Followers: 2)
Energy Storage     Hybrid Journal   (Followers: 2)
Journal of Microwave Power and Electromagnetic Energy     Hybrid Journal   (Followers: 2)
Australian Journal of Electrical and Electronics Engineering     Hybrid Journal   (Followers: 2)
Journal of Information and Telecommunication     Open Access   (Followers: 2)
TELKOMNIKA (Telecommunication, Computing, Electronics and Control)     Open Access   (Followers: 2)
Journal of Semiconductors     Full-text available via subscription   (Followers: 2)
Radiophysics and Quantum Electronics     Hybrid Journal   (Followers: 2)
International Transaction of Electrical and Computer Engineers System     Open Access   (Followers: 2)
Journal of Intelligent Procedures in Electrical Technology     Open Access   (Followers: 2)
Sensing and Imaging : An International Journal     Hybrid Journal   (Followers: 2)
Security and Communication Networks     Hybrid Journal   (Followers: 2)
Journal of Nuclear Cardiology     Hybrid Journal   (Followers: 2)
ECTI Transactions on Electrical Engineering, Electronics, and Communications     Open Access   (Followers: 1)
IET Energy Systems Integration     Open Access   (Followers: 1)
Majalah Ilmiah Teknologi Elektro : Journal of Electrical Technology     Open Access   (Followers: 1)
International Journal of Granular Computing, Rough Sets and Intelligent Systems     Hybrid Journal   (Followers: 1)
IEEE Letters on Electromagnetic Compatibility Practice and Applications     Hybrid Journal   (Followers: 1)
Journal of Computational Intelligence and Electronic Systems     Full-text available via subscription   (Followers: 1)
Електротехніка і Електромеханіка     Open Access   (Followers: 1)
Open Electrical & Electronic Engineering Journal     Open Access   (Followers: 1)
IEEE Journal of Electromagnetics, RF and Microwaves in Medicine and Biology     Hybrid Journal   (Followers: 1)
Journal of Advanced Dielectrics     Open Access   (Followers: 1)
Transactions on Cryptographic Hardware and Embedded Systems     Open Access   (Followers: 1)
International Journal of Hybrid Intelligence     Hybrid Journal   (Followers: 1)
Ural Radio Engineering Journal     Open Access   (Followers: 1)
IET Cyber-Physical Systems : Theory & Applications     Open Access   (Followers: 1)
Edu Elektrika Journal     Open Access   (Followers: 1)
Power Electronics and Drives     Open Access   (Followers: 1)
Automatika : Journal for Control, Measurement, Electronics, Computing and Communications     Open Access  
npj Flexible Electronics     Open Access  
Elektronika ir Elektortechnika     Open Access  
Emitor : Jurnal Teknik Elektro     Open Access  
IEEE Solid-State Circuits Letters     Hybrid Journal  
IEEE Open Journal of Industry Applications     Open Access  
IEEE Open Journal of the Industrial Electronics Society     Open Access  
IEEE Open Journal of Circuits and Systems     Open Access  
Journal of Electronic Science and Technology     Open Access  
Solid State Electronics Letters     Open Access  
Industrial Technology Research Journal Phranakhon Rajabhat University     Open Access  
Journal of Engineered Fibers and Fabrics     Open Access  
Jurnal Teknologi Elektro     Open Access  
IET Nanodielectrics     Open Access  
Elkha : Jurnal Teknik Elektro     Open Access  
JAREE (Journal on Advanced Research in Electrical Engineering)     Open Access  
Jurnal Teknik Elektro     Open Access  
IACR Transactions on Symmetric Cryptology     Open Access  
Acta Electronica Malaysia     Open Access  
Bioelectronics in Medicine     Hybrid Journal  
Chinese Journal of Electronics     Open Access  
Problemy Peredachi Informatsii     Full-text available via subscription  
Technical Report Electronics and Computer Engineering     Open Access  
Jurnal Rekayasa Elektrika     Open Access  
Facta Universitatis, Series : Electronics and Energetics     Open Access  
Visión Electrónica : algo más que un estado sólido     Open Access  
Telematique     Open Access  
International Journal of Nanoscience     Hybrid Journal  
International Journal of High Speed Electronics and Systems     Hybrid Journal  
Semiconductors and Semimetals     Full-text available via subscription  

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Similar Journals
Journal Cover
IEEE Transactions on Power Electronics
Journal Prestige (SJR): 2.215
Citation Impact (citeScore): 9
Number of Followers: 89  
 
  Hybrid Journal Hybrid journal (It can contain Open Access articles)
ISSN (Print) 0885-8993
Published by IEEE Homepage  [228 journals]
  • IEEE Power Electronics Society Information

    • Free pre-print version: Loading...

      Abstract: Presents a listing of the editorial board, board of governors, current staff, committee members, and/or society editors for this issue of the publication.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • IEEE Power Electronics Society Information

    • Free pre-print version: Loading...

      Abstract: Presents a listing of the editorial board, board of governors, current staff, committee members, and/or society editors for this issue of the publication.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Administrative Committee

    • Free pre-print version: Loading...

      Abstract: Presents a listing of the editorial board, board of governors, current staff, committee members, and/or society editors for this issue of the publication.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Fault Detection and Ride Through of CHB Converter-Based Star-Connected
           STATCOM Through Exploring the Inherent Information of Multiloop
           Controllers

    • Free pre-print version: Loading...

      Authors: Yuanhui Chen;Jinwei He;
      Pages: 1366 - 1371
      Abstract: A simple detection and ride-through operation approach is proposed for star-connected cascaded H-bridge (CHB) converter-based STATCOMs with a single IGBT open circuit fault. It adopts a modified current regulator with high gains at both dc and fundamental frequencies. Then, the output signals of the current regulator branches and the dc voltage balancing regulator are synthesized as an inherent indicator to quickly determine the position of the open-circuit fault IGBT. With this approach, the controller can also be considered as an inherent system state monitor, but without any additional sensors or computing burdens. Afterwards, in the ride-through operation stage, the faulty H-bridge module can switch to half-bridge operation and the corresponding dc offset voltage is compensated by the remaining healthy modules. It has been validated that the proposed approach is accurate in various conditions, including grid voltage and load disturbances.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Dual Stage Single-Phase to Multiphase Matrix Converter for Variable
           Frequency Applications

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      Authors: Manoj A. Waghmare;Bhimrao S. Umre;Mohan V. Aware;Atif Iqbal;Anup Kumar;
      Pages: 1372 - 1377
      Abstract: A single-stage matrix converter (MC) is preferred for the conversion of a single-phase $({1emptyset })$ supply of fundamental frequency (50 Hz) to the multiphase $({memptyset })$ power supply in a limited operating frequency range (5–15 Hz). These converters possess a limitation on account of voltage and current distortions when the converter is used up to fundamental or higher frequency operating loads. To resolve this problem, this letter proposes a dual-stage $1emptyset text{to} memptyset $ MC, which ensures improved power quality across the output voltage and current. This converter has a three-leg front-end side rectifier stage (RS) consisting of six numbers of common emitter configured bidirectional power semiconductor switches. A filter circuit is installed in between $1emptyset $ supply and RS enabling to build positive average dc voltage across the virtual dc link while maintaining the source current profile. The second stage is an inversion stage having a conventional voltage source inverter structure. The proposed dual-stage MC topology is having a simple structure with the ability to convert the $1emptyset $ supply to any number of desired output phases not only at the lower frequency but also at the fundamental and higher frequency. The practical applicability of the proposed dual-stage MC is validated through experimental results.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • An Independent Dual-Coil Driving Topology for Wireless Power Transfer

    • Free pre-print version: Loading...

      Authors: Houji Li;Ming Liu;Lingchao Kong;Yong Wang;
      Pages: 1378 - 1383
      Abstract: The existing dual-coil driving topology mostly adopts two inverters or additional switching circuit, which increases the cost and size, and the complexity of the wireless power transfer (WPT) system. In this letter, a novel inverter topology with independent dual-coil driving capability is proposed for WPT applications, where the main switch and auxiliary switch can drive two independent coils. Moreover, this topology not only offers wide zero voltage switching range and compact size, but also improves the output power and coil utilization. Meanwhile, a quadruple D square (QDS) coil with uniform magnetic field is discussed with the dual-coil driving topology. The detailed parameters design of the proposed topology is discussed and the QDS coil is compared with other coils in terms of magnetic flux intensity. Finally, a 1MHz and 220W wireless power transfer system is built to verify the proposed topology and coil structure.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • A Quasi-Two-Stage Isolated Bidirectional Buck-DAB Converter for Wide Input
           Voltage Range

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      Authors: Zhengmei Lu;Guo Xu;Wenjing Xiong;Yao Sun;Mei Su;
      Pages: 1384 - 1390
      Abstract: In this article, a quasi-two-stage buck-DAB (QBDAB) converter is proposed for improving the performance of the conventional dual active bridge (DAB) solution under a wide voltage range. For the proposed QBDAB converter, the DAB can always work under voltage matching conditions for wide voltage range applications, and the gain is adjusted through the added front-end circuit. The front-end circuit is similar to a buck converter, while only part of the transmission power flows through the circuit, which could also reduce the burden of achieving ZVS of the front-end circuit. Therefore, compared with the traditional two-stage buck-DAB converter solution, the related loss for the buck circuit can be reduced. The working principle, power transfer characteristics, and full load range ZVS design are analyzed deeply in this article. A detailed comparison of the QBDAB and other related combined buck+DAB topologies is also presented. Finally, the effectiveness of the proposed QBDAB is verified through experimental results from a 1kW prototype.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • A Resonant Modular Multilevel Rectifier for Secondary Control in Inductive
           Power Transfer

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      Authors: Jianting Li;Puyu Wang;Jianke Li;Jinquan Wang;Danhong Xue;Jingjing Chen;Shan Luo;Renzhong Xu;
      Pages: 1391 - 1397
      Abstract: Secondary control of the inductive-power-transfer (IPT) system can achieve robust output regulation by eliminating the long propagation delay of wireless communication in the feedback control between the transmitter and receiver. Recently, the multilevel switched-capacitor converter has been employed for rectification in the receiver, but experiences high charge sharing loss. In this letter, a resonant modular multilevel rectifier (RMMR) is proposed to eliminate the charge sharing loss in the conventional multilevel rectifier. The proposed RMMR is applied in a series–series compensated IPT system to implement independent secondary control for output voltage regulation with low harmonic distortion and reduced conduction loss. The operating principle is analyzed in detail and a generic analytical expression of the system voltage gain is provided. In addition, the operation of the proposed topology is validated experimentally, and a peak dc–dc efficiency of 96.6% is measured in the experiments.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Sensorless Current-Sharing Scheme for Multiphase DC-DC Boost Converters

    • Free pre-print version: Loading...

      Authors: Minghang Duan;Jiandong Duan;Li Sun;
      Pages: 1398 - 1405
      Abstract: Accurate current sharing is beneficial to realize uniform heat distribution and electrical stresses in multiphase converters. Most of the present current-sharing schemes need many current sensors which increase the cost and decrease the system reliability. To solve this problem, a sensorless current-sharing scheme is proposed to balance the phase currents of multiphase dc–dc boost converters in continuous conduction mode. By converting the inner resistances of inductors and switches to series resistances on the input side, the actual converter model is simplified. Regarding one duty cycle as reference, the relationship between duty cycle and series resistance ratio (SSR) is derived for equal current distribution. After that, two methods are provided to obtain the SSRs. One is based on duty disturbance and the other is based on current measurement. Actually, the phase with largest series resistance is chosen as reference to improve the transient response. Despite phase number, only output and input voltages are measured to achieve output voltage regulation and current balance in the overall control scheme. The validity of proposed scheme is verified on a three-phase dc–dc boost converter.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • A Novel Reduced-Order Generalized Differentiator With Zero-Phase Lag and
           Improved Noise Attenuation

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      Authors: Renzhi Huang;Xiangjun Quan;Zaijun Wu;Mingjin Hu;Qinran Hu;Zichen Wang;
      Pages: 1406 - 1411
      Abstract: The differentiator is widely used in power converter control to improve the control performance. However, the noise attenuation and phase lag always challenge the digital implementation of the differentiator. The existing differentiators, such as the high-pass filter, nonideal generalized integrator, and the discrete-time optimal control-based tracking differentiator, all face the same incompatible contradiction between noise attenuation and phase lag. The multiple second-order general differentiators lack polarity-selective property and suffer a huge computational burden. To address these issues, this letter proposes a novel reduced-order generalized differentiator (ROGD). Then, different discretization versions of the proposed ROGD and existing differentiators are discussed and compared to demonstrate that the proposed ROGD can achieve excellent performance for differentiation estimation with zero-phase lag and improved noise attenuation at the same time. The effectiveness of the proposed differentiator is finally verified by the differentiator simulation and the experiments of the grid-forming control where the differentiator is used.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • High-Frequency Injection Angle Self-Adjustment Based Online Position Error
           Suppression Method for Sensorless PMSM Drives

    • Free pre-print version: Loading...

      Authors: Guangdong Bi;Guoqiang Zhang;Qiwei Wang;Dawei Ding;Binxing Li;Gaolin Wang;Dianguo Xu;
      Pages: 1412 - 1417
      Abstract: In the high-frequency (HF) signal injection based position sensorless permanent magnet synchronous motor (PMSM) drives, there is an estimated position error caused by the cross-saturation effect and other factors. In order to suppress the position error, an HF injection angle self-adjustment based online suppression method is proposed in this letter. By tracking the sign of the increment of the absolute back electromotive force in the estimated frame, the criterion of the HF injection angle self-adjustment can be determined online and the position error can be mitigated effectively. This method can avoid the offline measurement or the variation of the operating state, which has a satisfactory suppression effect for the position error under different operating conditions. The effectiveness is verified by experiments on a 2.2-kW PMSM drive platform.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • A Novel Oscillating-Commutation Solid-State DC Breaker Based on Compound
           IGCTs

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      Authors: Xin Yan;Zhanqing Yu;Lu Qu;Zhizheng Gan;Rong Zeng;Yulong Huang;Jian Feng;Gongyi Zhang;
      Pages: 1418 - 1422
      Abstract: Medium voltage dc system has fast rise rate in the event of a short-circuit fault. To avoid high-peak fault current, it is necessary to configure dc circuit breaker with fast operation. Solid-state dc circuit breaker has short breaking time and high reliability, which is suitable for Dc system. In this letter, a novel oscillating-commutation solid-state dc circuit breaker based on compound integrated gate-commutated thyristors (IGCTs) is proposed. By combining IGCTs with different advantages, such as high current breaking and high withstand-voltage capability, the proposed dc breaker has the advantages at less breaking time, high performance, low cost, and small volume. The working principle of the proposed scheme is described in detail, and an 8 kV prototype with 7 kA current breaking ability is built to verify its feasibility.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • ${V}_{text{TH}}$ +Compensation+for+Wireless+Biomedical+Implants&rft.title=IEEE+Transactions+on+Power+Electronics&rft.issn=0885-8993&rft.date=2023&rft.volume=38&rft.spage=1423&rft.epage=1428&rft.aulast=Ha;&rft.aufirst=Muhammad&rft.au=Muhammad+Abrar+Akram;Sohmyung+Ha;">A 434-MHz Bootstrap Rectifier With Dynamic ${V}_{text{TH}}$ Compensation
           for Wireless Biomedical Implants

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      Authors: Muhammad Abrar Akram;Sohmyung Ha;
      Pages: 1423 - 1428
      Abstract: This letter presents a fully differential CMOS bootstrap rectifier with an effective dynamic threshold voltage (i.e., ${V}_{text{TH}}$) compensation (DVC). The bootstrapping circuit for DVC, which consists of a dynamically biased transistor, a series resistor, and a parallel capacitor, dynamically generates a compensation voltage for the main rectifying pass transistors only when the ${V}_{text{TH}}$ compensation is required. It significantly increases the proposed rectifier's power conversion efficiency (PCE) compared to other bootstrap rectifiers. The proposed rectifier operates at an industrial, scientific, and medical (ISM) band frequency of 434 MHz, and it is fabricated in a 0.18-$mu$m CMOS process together with two conventional bootstrap rectifiers for performance comparison. Measurement results validate that the proposed rectifier outperforms the conventional bootstrap rectifiers in terms of the output dc voltage level, voltage conversion ratio, and PCE. The proposed rectifier attains a peak PCE of 71$%$ at a load resistor of 3 k$Omega$ and an operating frequency of 434 MHz.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • A Novel Wider Range Modulation for Indirect Matrix Converter Utilizing
           Delta-Sigma and Space Vector

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      Authors: Chaolei Ma;Tingna Shi;Zhichen Lin;Zhanqing Zhou;Changliang Xia;
      Pages: 1429 - 1434
      Abstract: The coupling between the rectifier and inverter makes the modulation of the indirect matrix converter (IMC) relatively complicated. A novel modulation method is proposed in this letter, where a space vector modulation without a zero-voltage vector, which is only responsible for adjusting the phase of the output voltage vector, is used for the inverter, and a novel delta-sigma method (ΔΣM) to modulate the input current vector phase and dc-link voltage is adopted by the rectifier. Duty cycles of the inverter are obtained by looking up the table of reference output voltages and updated at a 5-kHz carrier cycle, while switching states of the rectifier change once per cycle at a 40-kHz sampling frequency. By decoupling the rectifier and inverter, modulation of the IMC is greatly simplified. Methods that optimize the selection of rectifier switching states under various output/input voltage transfer ratios are also discussed. Simulations and experimental results are presented to validate the proposed method.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • A Suppression Method for Gate-Source Voltage Oscillation With Clamping
           Function for GaN Devices

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      Authors: Jian Chen;Jianping Xu;Wensheng Song;Quanming Luo;H. Alan Mantooth;
      Pages: 1435 - 1439
      Abstract: Gallium nitride (GaN) devices are generally more prone to severe switching oscillations than Si mosfets due to their fast switching speeds. Different from Si and SiC mosfets, GaN devices typically have a lower maximum gate voltage rating. Taking the Efficient Power Conversion Corporation series as an example, the gate drive voltage is usually 5 V, but the maximum voltage rating is 6 V. Therefore, GaN devices are more susceptible to damage from gate-source voltage oscillation. In this letter, a gate drive circuit with a clamping function is proposed to suppress gate-source voltage oscillation. The adopted method can not only clamp the gate voltage of the GaN device near the drive voltage to protect the device, but also does not affect the switching speed of the device. The proposed method mainly uses some passive components that make the circuit design simpler compared with other active gate driver methods. Finally, the effectiveness of the proposed method is verified by experiments.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Wireless Power and Data Transfer System Using Multidirectional Magnetic
           Coupler for Swarm AUVs

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      Authors: Yingqin Zeng;Conghui Lu;Renzhe Liu;Xiangrui He;Cancan Rong;Minghai Liu;
      Pages: 1440 - 1444
      Abstract: In this letter, a simultaneous wireless power and data transfer system based on a novel multidirectional magnetic coupler is presented for the application of swarm AUVs. The transmitting coil consisting of two reversely wound helix loops can generate a multidirectional magnetic field in space, which supplies power to multiple arc-shaped receiving coils placed in different directions. Aiming at high coupling strength and low core volume, a multiobjective genetic algorithm is used to optimize coil parameters. In addition, a hybrid injection communication method based on LCC-S compensation topology is proposed and analyzed. An experiment platform is built and the results show that the system can achieve 92.25% efficiency at a power level of 200 W when four AUVs are powered. Meanwhile, the transferred data are successfully recovered at the data rate of 30 kbps.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Vulnerability of a VOC-Based Inverter Due to Noise Injection and Its
           Mitigation

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      Authors: Sourojit K. Mazumder;Mateo D. Roig Greidanus;Ji Liu;H. Alan Mantooth;
      Pages: 1445 - 1450
      Abstract: Even though virtual oscillator control (VOC)-based inverters do not communicate with each other, they need to make local measurements for control. The impact of tampering with these measured or sensed signals on the performance of a VOC-based inverter and synchronization of multiple such inverters is an important but open-ended issue. As such, this letter explores the impact of intentional side-channel noise intrusion (SNI) on the synchronization of VOC-based communication-free self-synchronizing inverters (CFSIs). Two different scenarios are investigated via experimental and analytical studies using a half-bridge neutral point clamped (NPC) single-phase CFSI. They address the impact of SNI on the ability of a CFSI to ensure a stable 60-Hz limit cycle and on the parallel operation of two such CFSIs to ensure synchronism to a common 60-Hz load frequency.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Long-Term Memory Recursive Least Squares Online Identification of Highly
           Utilized Permanent Magnet Synchronous Motors for Finite-Control-Set Model
           Predictive Control

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      Authors: Anian Brosch;Oliver Wallscheid;Joachim Böcker;
      Pages: 1451 - 1467
      Abstract: Highly utilized permanent magnet synchronous motors (PMSM) characterized by their nonlinear magnetization due to (cross-)saturation effects are the common choice when highest power density is required. For precise torque and current control, these motors are usually characterized by extensive offline measurements on a test bench, finally resulting in look-up tables of the relations between torque, flux, and current. In contrast, this article proposes a long-term memory recursive least squares (LTM-RLS) current estimator optimized for finite-control-set (FCS) model predictive controllers (MPC). This approach is able to identify the differential inductance and flux linkage maps for online self-commissioning without additional signal injection in only few seconds. This is achieved by extending the local RLS identification with an additional long-term memory. By continuously adapting the flux linkage maps, a precise open-loop torque control can be realized without the knowledge of exact motor parameters except the stator resistance as datasheet parameter. Extensive experimental investigations demonstrate accurate predictions of the identified model and, thus, highest control performance of the FCS-MPC during transient and steady-state operation and small torque estimation errors of less than $1.2 ,%$ for speeds greater than $50 ,%$ of the PMSM's nominal speed. Even for speeds of only $5 ,%$ of the nominal speed, the estimation error is less than $7 ,%$.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Online Condition Monitoring of Solder Fatigue in a Clip-Bonding SiC mosfet
           Power Assembly via Acoustic Emission Technique

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      Authors: Zheng Zhang;Chuantong Chen;Aiji Suetake;Hiroshi Ishino;Hirokazu Sampei;Takeshi Endo;Kazuhiko Sugiura;Kazuhiro Tsuruta;Katsuaki Suganuma;
      Pages: 1468 - 1478
      Abstract: In this work, an acoustic emission (AE) technique was applied to online condition monitoring (CM) of solder fatigue in a clip-bonding SiC mosfet power assembly during short and long power cycling tests (PCTs). Solder fatigue caused by PCTs was identified in the clip-bonding assembly via scanning acoustic tomography and scanning electron microscopy and successfully diagnosed via the AE-based online CM. By analyzing AE signals, junction temperature, and junction-to-case thermal resistance, it can be confirmed that the AE signal shows a superior sensitivity in initial fatigue diagnosis to the thermal or electrical signals. Meanwhile, two solder fatigue processes, cracking initiation and cracking acceleration, were identified based on the cumulative AE counts and AE energy during the long PCT. An abrupt increase in AE energy happened at the end stage of the long PCT due to a severe cracking process, which can be regarded as a prewarning of a failure point of the power assembly. In addition, the relationship between transitional thermal resistance and accumulative AE energy was investigated and shows a linear relationship. These results suggest that the AE technique can be a promising online CM approach to diagnose and predict solder fatigue in power assemblies during operation.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • 3.5-kW 94.2% DC–DC Efficiency Capacitive Power Transfer With Zero
           Reactive Power Circulating

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      Authors: Yao Wang;Hua Zhang;Fei Lu;
      Pages: 1479 - 1484
      Abstract: Most existing capacitive power transfer (CPT) circuits are developed from basic series–series CPT compensation, which have a common drawback of unavoidable reactive power circulating from the primary side of the capacitive coupler to its secondary side, causing reactive power loss, weakening power transfer capability, and aggravating electric field emission. To solve these concerns, this letter proposed a parallel–parallel (PP) compensation-based CPT system with double-side series–parallel (SP) inductive power transfer (IPT) links. The PP CPT compensation aims at zero reactive power circulating while the SP IPT links achieve high-power transfer capability. A 2.5-MHz prototype is implemented, and experiments validate the zero reactive power circulating property with 3.55 kW output power at a 94.2% dc–dc efficiency, and the peak efficiency achieves 94.6% at 1.62 kW output power. This letter is accompanied by slides as multimedia material demonstrating the motivations, contributions, and advantages over existing state-of-the-art CPT designs.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Simple Switching Strategies for dv/dt Reduction in SiC-Device-Based
           Modular Multilevel Converters

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      Authors: Xiao Li;Rui Liu;Ziwei Ke;Jianyu Pan;Boxue Hu;Risha Na;Longya Xu;Jin Wang;
      Pages: 1485 - 1493
      Abstract: This article presents two simple strategies for output dv/dt reduction in modular multilevel converters through coordination of the switching transients of the submodules. The first method is achieved by adding a delay time between the switching transients of two submodules, which would be switched simultaneously in regular switching strategies of modular multilevel converters. The second method is to inject a reverse dv/dt to the converter's output by switching redundant submodules. Both methods do not affect the switching speeds of the semiconductor devices and require no additional hardware components. They can be applied with different modular multilevel converters modulation strategies. Circuit analysis of the proposed methods and their effects on the converter operation are presented. Simulation and test results of a 1.7-kV SiC-device-based modular multilevel converter are provided to validate the circuit analysis. It is shown that the proposed methods can reduce the converter's output dv/dt to half of a single switching device's dv/dt.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • The Analysis and Calculation of Power Angle Dynamics in Grid Forming
           Converter Under Large Disturbances Based on KBM Asymptotic Method

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      Authors: Jintao Lei;Xin Xiang;Wuhua Li;Xiangning He;
      Pages: 1494 - 1508
      Abstract: Grid forming (GFM) control strategy has been increasingly used in grid-connected converters to regulate system frequency and mimic the inertia of synchronous generator. However, the description of its power angle dynamics under large disturbances is still lacking up to date, which may pose great challenges to stable operation and economic configuration of grid-connected converters in the future power system. To overcome the aforementioned obstacle, a Krylov–Bogoliubov–Mitropolsky (KBM) asymptotic method with the perturbation theory is presented first in this article to derive an analytical solution for power angle trajectory under large disturbances. Considering that the antiderivative problem is usually unsolvable due to the complicated perturbation function, a tailored integral method is further proposed to address this problem and simplify the final result, which facilitates the KBM asymptotic method to the analysis and calculation of power angle trajectory. As a result, an explicit and accurate time-domain expression is obtained, and it reveals the quantitative relationships between control parameters and dynamic characteristics, which may provide a good potential for system transient stability analysis and GFM converter design. In the end, the effectiveness and accuracy of the proposed method are verified by both simulations and control-hardware-in-loop experiments.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Impacts of Current Limiting on the Transient Stability of the Virtual
           Synchronous Generator

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      Authors: Kourosh Gharouni Saffar;Sina Driss;Firouz Badrkhani Ajaei;
      Pages: 1509 - 1521
      Abstract: This article investigates the impacts of different current limiting strategies on the transient stability of the virtual synchronous generator (VSG). The power–angle curve of the VSG under different operating conditions is theoretically characterized in detail and experimentally verified through tests conducted on hardware-implemented lab-scale VSGs. It is shown that the reference current saturation approaches prioritizing the current vector angle, the d-axis current, and the q-axis current reshape the VSG power–angle curve in different ways. The resulting impacts on the VSG transient stability are comprehensively investigated through time-domain simulation of a battery energy storage system that is operated as a VSG and connected to a medium-voltage Canadian distribution feeder. The transient stability margin of the VSG is evaluated by determining the critical clearing time (CCT) of various fault scenarios. The studies conducted in the PSCAD/EMTDC software environment utilizing a detailed switching model of the VSG indicate that 1) the current limit of the VSG significantly impacts its power output during and after faults; and 2) the q-axis priority current limiting strategy provides a larger transient stability margin (CCT) as compared with the current vector angle and d-axis current priority approaches.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • $LLC$ +Cascaded+Converter+With+a+Wide+Input+Voltage+Range&rft.title=IEEE+Transactions+on+Power+Electronics&rft.issn=0885-8993&rft.date=2023&rft.volume=38&rft.spage=1522&rft.epage=1534&rft.aulast=Loh;&rft.aufirst=Weikang&rft.au=Weikang+Wang;Yang+Liu;Jin+Zhao;Peng+Zhang;Poh+Chiang+Loh;">A Dynamic Control Method for Buck + $LLC$ Cascaded Converter With a Wide
           Input Voltage Range

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      Authors: Weikang Wang;Yang Liu;Jin Zhao;Peng Zhang;Poh Chiang Loh;
      Pages: 1522 - 1534
      Abstract: DC–DC converters with a wide input voltage range have earned numerous daily applications in the industry. An example is power systems for electric vehicles, where $LLC$ converters with remarkable features have also been deployed to provide isolation. It is, therefore, common to find a front buck converter cascaded to a back $LLC$ converter, where their intermediate bus voltage is set low to accommodate the lowest input voltage to the buck converter. Unfortunately, this causes efficiency to drop at a high input voltage. To avoid the drop, a reconfiguring strategy has been proposed to convert the front buck converter from full bridge to half bridge, as its input voltage rises above a specified threshold. Furthermore, to ensure a smooth and fast reconfiguration, a dynamic control method has been proposed to direct the intermediate bus voltage to track a reference trajectory with a lower current surge. Besides, the method employs pulse-shift modulation to keep a stable output voltage and proper control initialization to prevent oscillation during the transition. These favorable features and an overall higher efficiency have subsequently been verified through experimental testing with a wide input voltage range.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Inverse Application of Artificial Intelligence for the Control of Power
           Converters

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      Authors: Yuan Gao;Songda Wang;Habibu Hussaini;Tao Yang;Tomislav Dragičević;Serhiy Bozhko;Patrick Wheeler;Sergio Vazquez;
      Pages: 1535 - 1548
      Abstract: This article proposes a novel application method, inverse application of artificial intelligence (IAAI) for the control of power electronic converter systems. The proposed method can give the desired control coefficients/references in a simple way because, compared to conventional methods, IAAI only relies on a data-driven process with no need for an optimization process or substantial derivations. Noting that the IAAI approach uses artificial intelligence to provide feasible coefficients/references for the power converter control, rather than building a new controller. After illustrating the IAAI concept, a conventional application method of artificial neural network is discussed, an optimization-based design. Then, a two-source-converter microgrid case is studied to choose the best droop coefficients via the optimization-based approach. After that, the proposed IAAI method is employed for the same microgrid case to quickly find good droop coefficients. Furthermore, the IAAI method is applied to a modular multilevel converter (MMC) case, extending the MMC operation region under unbalanced grid faults. In the MMC case, both simulation and experimental online tests validate the operation, feasibility, and practicality of IAAI.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Online Inductance Identification and FPGA-Based Real-Time Digital Control
           Design for APF

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      Authors: Yousong Zhou;Jiangpeng Yang;Linghui Meng;Jiaxuan Yao;Lan Ma;Haiquan Zhao;Zeliang Shu;
      Pages: 1549 - 1561
      Abstract: The harmonic suppression performance of active power filter (APF) under model predictive current control is obviously reduced, when the parameter exists a mismatch between the actual value in system and the nominal value adopted in the control. To suppress the influence of parameter mismatching, a model predictive control based on parameter identification with forgetting factor recursive least square (FFRLS) method is proposed for APF. The digital processing procedure of the FFRLS-based APF controller is detailed analyzed and designed. The identification error of inductance between identification value and the actual value is less to 6%, and the total harmonic distortion of grid current is significantly improved, especially a lower value of actual inductance. Simulation and experimental results show that the proposed method can not only effectively eliminate the influence of parameter mismatch on the control, but also result in better steady-state performance while retaining fast dynamic response.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Adaptive Control of Grid-Connected Inverters With Nonlinear LC Filters

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      Authors: Hossein Safamehr;Tooraj Abbasian Najafabadi;Farzad Rajaei Salmasi;
      Pages: 1562 - 1570
      Abstract: Distributed generation is an effective solution to clean, reliable, and cost-efficient energy supply. In this framework, inverters play a key role as energy converters. Accordingly, this article investigates the utilization of nonlinear inductive–capacitive (LC) filters for grid-connected inverters. Nonlinear LC filters are made of inductors with nonlinear B–H curves, which makes them have a smaller volume, less dissipation loss, and lower cost. The main drawback of using these filters, however, is their nonlinear current-dependent characteristics. To harness the undesirable impacts of nonlinear filters on the system performance, an adaptive observer-based control scheme is developed in this article. The proposed controller is based on a concurrent estimation of nonlinear inductor values, capacitor voltages, and grid-side currents. Based on its fast adaptation to plant changes, this scheme provides an improved stability margin and an inherent resonant damping characteristic under grid impedance uncertainty. Compared with the conventional approaches, this method requires no extra sensors. A comparative simulation and experimental analysis, based on a three-phase 7-kW inverter, is provided to validate the efficacy of the proposed control strategy.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Virtual Three-Level Model Predictive Flux Control With Reduced
           Computational Burden and Switching Frequency for Induction Motors

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      Authors: Tao Jin;Huiqing Song;Daniel Legrand Mon-Nzongo;Paul Gistain Ipoum-Ngome;Huangzheng Liao;Minlong Zhu;
      Pages: 1571 - 1582
      Abstract: Model predictive flux control (MPFC) is an alternative control solution to the classic model predictive torque control (MPTC) for driving induction motors (IMs) without the complexity of tuning the weighting factors. However, when applied in motor drives fed by a two-level converter, it results in higher flux and torque ripples. To improve its performance, this article proposes a virtual three-level MPFC (V3-MPFC) method. The virtual vector method increases the total number of voltage vectors crucial for improving the closed-loop performances of the model predictive control. To reduce the computational burden, direct torque control and novel deadbeat (DB) control strategies are proposed. Compared with existing methods, the proposed DB-based method reduces V3-MPFC to a suboptimization problem and still ensures that the suboptimal solution is equivalent to the global optimal solution provided by V3-MPFC. In addition, the redundant states are exploited to lower the switching frequency (SF) without extending the cost function. The simulation and experiment results show that, compared with existing methods, the proposed strategy effectively reduces the flux and torque ripples, and requires a lower SF and execution time.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Overview of Single-Stage High-Frequency Isolated AC–DC Converters
           and Modulation Strategies

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      Authors: Fengjiang Wu;Kaixuan Wang;Guangfu Hu;Yang Shen;Suhua Luo;
      Pages: 1583 - 1598
      Abstract: The single-stage high-frequency (HF) isolated ac–dc converter has the advantages of high-power density, long life, and high efficiency. It has a broad application prospect in distributed power generation, ac microgrid, and energy storage system. In this article, its topologies are classified according to the energy storage components. The structure and operating principle of various topologies are introduced. Furthermore, the development of extended multiport single-stage HF isolated ac–dc converter is introduced. On this basis, the advantages and disadvantages, typical characteristics, cost, and power loss of various topologies are analyzed and summarized. Finally, the key issues that need to be solved are pointed out and the development trends are explored. This article aims to provide a reference for the subsequent research on single-stage HF isolated ac–dc converters and the advancement of their practicability.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Filter- and Observer-Based Finite-Time Adaptive Fuzzy Control for
           Induction Motors Systems Considering Stochastic Disturbance and Load
           Variation

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      Authors: Panpan Ma;Jinpeng Yu;Qing-Guo Wang;Jiapeng Liu;
      Pages: 1599 - 1609
      Abstract: In this article, a finite-time adaptive fuzzy control scheme based on filter and reduced-order observer is proposed for induction motors (IMs) with load variation. First, the rotor position and the angular velocity of IMs are estimated by a reduced-order observer. Second, the unknown stochastic nonlinear functions are handled by the fuzzy logic systems. In addition, the finite-time control is combined with command filtering to solve the issue of “explosion of complexity” in the traditional backstepping method, and the errors compensation signal is introduced to reduce the filtering error, which can ensure the finite-time convergence and improve the robustness of the systems. The simulation and experimental results are given for validation of the proposed control strategy.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Evaluation of Current-Mode Controller for Active Battery Cells Balancing
           With Peak Efficiency Operation

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      Authors: Mohammad K. Al-Smadi;Jaber A. Abu Qahouq;
      Pages: 1610 - 1621
      Abstract: This article presents a current-mode controller for switched-inductor topology to achieve voltage balancing between battery cells or modules in a battery pack while operating at peak efficiency. The presented method yields several advantages and/or eliminates several drawbacks of the existing conventional fixed duty cycle scheme. Among these advantages: 1) the balancing current is well controlled instead of being a function of battery cells’ voltages and system parasitic elements, which might result in exceeding the current ratings of the components, and 2) the balancing current reference is selected such that the balancing circuit operates at its maximum efficiency point and, therefore, yielding lower balancing power losses. This article also presents a battery balancing algorithm for utilization with the presented controller that achieves open circuit voltage balancing, which is a more accurate indicator of state-of-charge compared to terminal voltage. Experimental results obtained from a laboratory prototype of a three-cell battery pack are presented to evaluate the presented current control and balancing method under different modes of operation.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Optimized Carrier-Based DPWM Strategy Adopting Self-Adjusted Redundant
           Clamping Modes for Vienna Rectifiers With Unbalanced DC Links

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      Authors: Zhijian Zhang;Binxing Li;Guoqiang Zhang;Gaolin Wang;Zhaobin Huang;Bin Hu;Tan Long;Dianguo Xu;
      Pages: 1622 - 1634
      Abstract: When the Vienna rectifier operates at unbalanced dc links, the conventional carried-based discontinuous pulsewidth modulation (CB-DPWM) strategy suffers from the neutral point (NP) voltage fluctuation and the input current distortion. An optimized CB-DPWM strategy adopting self-adjusted redundant clamping modes is proposed in this article to solve the above issues. To reduce the input current distortion under unbalanced dc links, the modulation waves of CB-DPWM are modified according to the subsector redivision, and the limited operation region can be obtained. To extend the operation range of the Vienna rectifier, the voltage vector trajectory of CB-DPWM is optimized combined with the current error minimization and the voltage loss area compensation. To minimize the NP voltage fluctuation, the redundant clamping modes under unbalanced dc links are self-adjusted in real time according to the unbalanced degree. Moreover, the NP voltage fluctuation of the proposed strategy is evaluated by the root mean square of the NP current fluctuation. The effectiveness of the proposed strategy is verified by experiments on a Vienna rectifier platform.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Multivariable Control Design for Grid-Forming Inverters With Decoupled
           Active and Reactive Power Loops

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      Authors: Dayan Bandara Rathnayake;Behrooz Bahrani;
      Pages: 1635 - 1649
      Abstract: Grid-forming inverters (GFMIs) are recognized as a prominent driver toward achieving renewable energy-rich power grids. Unlike grid-following inverters (GFLIs), which are controlled as current sources, GFMIs are controlled as voltage sources. In GFMIs, dynamic control of the magnitude ($V_{mathrm{c}}$) and angle ($theta$) of the point of common coupling (PCC) voltage is used to achieve active ($P$) and reactive ($Q$) power transfer across a line. However, independent control of $P$ and $Q$ via $V_{mathrm{c}}$ and $theta$ becomes challenging due to the coupling between $P$ and $Q$ loops. The coupling becomes severe as the resistance-to-reactance ratio of the grid impedance and the power angle between the GFMI and the grid voltages are increased. This article proposes a novel multivariable controller to completely decouple $P$ and $Q$ loops in GFMIs. The proposed multivariable controller could be designed based on the prevalent control structures for GFMIs such as droop controller, swing equation-based virtual synchronous generator (VSG) controller, zero steady-state error reactive power controller, and fixed steady-state error-reactive power controller. The additional cross-channel decoupling controllers in the proposed multivariable controller provide superior decoupling action over the existing decoupling methods, such as the virtual inductor-based method. An $mathcal {H}_infty$-based method is adopted to tune the proposed multivariable controller parameters, where the straightforward formulation of the desired closed-loop dynamics based on the open-loop system is clearly shown. The decoupling performance of the controller is experimentally validated extensively. The experimental results show that the proposed controller results in superior performance over the prevalent decoupling methods, such as the virtual-inductor decoupling method.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • A Novel Modulation Method Based on Model Prediction Control With
           Significantly Reduced Switching Loss and Current Zero-Crossing Distortion
           for Vienna Rectifier

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      Authors: Qingyan Zhang;Fang Liu;Weidong Jiang;Jinping Wang;Yimin Yue;
      Pages: 1650 - 1661
      Abstract: Finite control set model predictive control (FCS-MPC) is widely used in rectifiers due to its fast response. When there are multiple control objectives, the optimal switching sequence is selected by minimizing the cost function with weighting factors. However, the reduction of current ripple caused by output error and switching loss is in conflict to a certain extent for FCS-MPC. In addition, when multiple objectives are controlled, the selection of weighting factor is a serious challenge. Therefore, a modulation method based on continuous control set model predictive control is proposed in this article. Two phases are clamped and one phase is modulated, which not only can significantly reduce the switching loss without increasing the computational burden, but also can control the neutral point voltage without using weighting factors. In addition, when the proposed method is adopted, current zero-crossing distortion can be suppressed over the full range of modulation index. The effectiveness of the proposed method is verified by simulation and experimental results.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • A Frequency-Adaptive Delay Signal Cancelation Based Filter to Reduce
           Position Estimation Error for Sensorless IPMSM Drives

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      Authors: Zheng Wu;Chenwen Cheng;Wei Hua;Yuchen Wang;Hengliang Zhang;Wei Wang;
      Pages: 1662 - 1671
      Abstract: In a sliding mode observer-based sensorless drive system, the estimated back electromotive force (BEMF) always contains abundant low-order harmonics caused by nonideal factors, e.g., flux spatial harmonics, inverter nonlinearity, and current measurement error, resulting in large estimated position errors. In previous studies, adaptive notch filters are usually adopted to suppress the BEMF harmonics. However, these filters suffer from enormous computation and increase system complexity, especially facing numerous low-order harmonics. In this article, a new frequency-adaptive notch filter employing delay signal cancelation (DSC) is proposed, which can be tailored to eliminate multiple harmonics with a simple structure. First, Lagrange interpolation is applied to realize fractional-order delay in the frequency-adaptive DSC (FADSC). Then, a frequency-dividing record method is designed to shorten the recording array length for the FADSC at low speed. Next, a switching procedure is introduced to change the frequency-dividing factor smoothly at different speeds. Finally, the transformation matrix in the DSC is changed in the FADSC by adding the rotation direction to make it suitable to forward and reverse rotations of an interior permanent magnet synchronous machine (IPMSM). The accuracy of the estimated rotor position can be improved by FADSC, which is verified by experiments on a prototype IPMSM.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Real-Time Feasibility of Data-Driven Predictive Control for Synchronous
           Motor Drives

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      Authors: Paolo Gherardo Carlet;Andrea Favato;Riccardo Torchio;Francesco Toso;Saverio Bolognani;Florian Dörfler;
      Pages: 1672 - 1682
      Abstract: The data-driven control paradigm allows overcoming conventional troubles in the controller design related to model identifications procedures. Raw data are directly exploited in the control input selection by forcing the future plant dynamics to be coherent with previously collected samples. This article focuses, in particular, on the data-enabled predictive control algorithm. A relevant disadvantage of this algorithm is the fact that the complexity of the online control program grows with the dimension of the dataset. This issue becomes particularly relevant when considering embedded applications, such as the control of synchronous motor drives, characterized by challenging real-time constraints. This work proposes a systematic approach for dramatically reducing the complexity of such algorithms. Such methodology enables real-time feasibility of the constrained version of this control structure, which was previously precluded. Simulations and experimental results are provided to validate the method, considering the current control of an interior permanent magnet motor as test-case.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • UDE-Based Current Controller With Enhanced Grid Frequency Fluctuation
           Adaptability for LCL-Type Grid-Tied Inverters

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      Authors: Yongkang Xiong;Yongqiang Ye;Mingzhe Zhu;
      Pages: 1683 - 1691
      Abstract: The uncertainty and disturbance estimator (UDE) with a time delay filter has been widely used for inverter systems due to its satisfactory harmonic rejection performance. However, the control performance may be affected when the grid frequency fluctuates. In this article, a modified UDE (FUDE) is proposed to improve the grid frequency fluctuation adaptability of the $LCL$ grid-tied inverter systems, which contains a compound filter consisting of time delay, zero-phase low-pass, and high-pass filters. Compared with the traditional time delay UDE, it can offer a wider notch bandwidth at the selected frequencies. A dual-loop controller is built in the separate-structure-type UDE-based controller, containing an outer loop PR controller and an inner loop FUDE. The sufficient conditions for the system stability are obtained by the small-gain theorem. The comparison experiments of the dual-loop controller with the proposed FUDE and the conventional time delay zero-phase low-pass UDE are performed on a 2-kW experimental platform, and the results demonstrate the effectiveness of the proposed FUDE.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Machine Learning Methods for Feedforward Power Flow Control of
           Multi-Active-Bridge Converters

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      Authors: Mian Liao;Haoran Li;Ping Wang;Tanuj Sen;Yenan Chen;Minjie Chen;
      Pages: 1692 - 1707
      Abstract: Controlling the multiway power flow in a multi-active-bridge (MAB) converter is important for achieving high performance and sophisticated functions. Traditional feedforward methods for MAB converter control rely on precise lumped circuit models. This article presents a machine learning (ML) method for the feedforward power flow control of an MAB converter without a precise circuit model. A feedforward neural network was developed to capture the nonlinear characteristics and predict the phases needed to achieve the targeted power flow. The neural network was trained with a large amount of data, collected with a set of known phase angles. This trained network was used to predict the phases to achieve the targeted power flow. A six-port MAB converter was built and tested to validate the methodology and demonstrate the “machine-learning-in-the-loop” implementation. Transfer learning was proven to be effective in reducing the size of the training data needed to obtain an accurate ML model. ML-based feedforward power flow control can achieve comparable accuracy as traditional model-based methods and can function without a precise lumped circuit element model of the MAB converter.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • A Novel Dead-Time Elimination Method for Voltage Source Multilevel
           Converters

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      Authors: Ziyue Xin;Fei Xiao;Liangdeng Hu;Wenjie Wu;Xujie Lou;Cheng Guo;
      Pages: 1708 - 1719
      Abstract: Voltage source multilevel converters (MLCs) are widely applied in recent years in a wide range of industrial applications. However, time delay inserted in switching signals to prevent short through can cause the dead-time effects, including output waveform distortion and voltage drop. In many kinds of MLCs, the freewheeling paths during dead time can also produce unexpected output voltage levels, which can cross a few consecutive output levels, introducing large dv/dt. Typical examples of those MLCs are 5L-active neutral-point-clamped, 7L-hybrid-clamped, 4L-nested neutral-point-clamped (NNPC) converter, etc. To solve this problem, a generic dead-time elimination (DTE) method is proposed. This method splits the complementary switches and replaces them with controllable switches coupled with uncontrollable diodes, decomposing the phase-leg of the converter into two basic switching cells, thus obviating the need for dead time. To address the zero-current clamping effect inherent to the DTE method, a second-order generalized integrator frequency-locked loop based current detector is also developed. The proposed DTE method is suitable for various MLCs. It cannot only effectively eliminate the unexpected levels, but also significantly reduce the output distortion and regains the output rms value. An application example of 4L-NNPC converter is given. The effectiveness of the proposed method is verified by both simulation and experiment.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Adaptive Model Predictive Control of an Interleaved Boost Converter Using
           Real-Time Updated Model

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      Authors: Hongyu Zhang;Yuren Li;Renyou Xie;Jian Song;Bo Liang;Yigeng Huangfu;
      Pages: 1720 - 1731
      Abstract: To optimize the voltage regulation performance and enhance the robustness, an adaptive model predictive controller is proposed in this article for an interleaved dc–dc boost converter. The predictive model is constructed by linearizing the nonlinear equations of the converter at the current operating point. A novel parameter update mechanism is developed based on the static model, which enables fast and accurate identification of the model parameters, thus the control law can guarantee the desired control performance in the wide operating range. Based on the adaptive model, a disturbance observer is constructed to correct the model predictions and mitigate parameter uncertainties. Then an explicit control law is derived by solving the optimization problem offline, and the stability analysis is carried out using the linear control theory. Finally, the effectiveness of the proposed method is verified by both simulation and experimental results.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • An Adaptive Current-Source Gate Driver for High-Voltage SiC mosfets

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      Authors: Gard Lyng Rødal;Dimosthenis Peftitsis;
      Pages: 1732 - 1746
      Abstract: This article presents a novel current-source gate driver for Silicon Carbide (SiC) metal oxide semiconductor field-effect transistors (mosfets) with adaptive functionalities. The proposed driver aims to decouple and improve controllability of $di/dt$, $dv/dt$, as well as to decrease turn-on and turn-offdelay times compared to conventional totem-pole voltage-source gate drivers and conventional current-source gate drivers. The circuit topology of the proposed gate driver and the working principle are analyzed for the turn-on and turn-offprocesses. Furthermore, the driving requirements in terms of gate voltage and gate current for SiC mosfets that determine the design and tuning of gate drivers are presented. The performance of the proposed gate driver is validated experimentally on a 3.3 kV/750 A SiC mosfet half-bridge power module. It is shown that, compared to conventional voltage-source gate drivers, the driver is capable of significantly reducing turn-on and turn-offdelay times by approximately 57% and 33%, respectively. Moreover, the proposed gate driver enables 233% controllability of $di/dt$ and 87% of $dv/dt$.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • A Method to Derive the Coupling Thermal Resistances at Junction-to-Case
           Level in Multichip Power Modules

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      Authors: Guoyou Liu;Xiang Li;Yangang Wang;Xuejiao Huang;Guiqin Chang;Haihui Luo;
      Pages: 1747 - 1756
      Abstract: A method to derive the junction-to-case level coupling thermal resistances among paralleling chips in the multichip semiconductor power module has been proposed in this article. It is revealed that the traditional structure function methodology (SFM), which is developed for analyzing the self-heating effect of the driving-point chip, cannot be applied directly in the thermal coupling analysis, where the influence of the driving-point chip on the neighboring acceptor chip is concerned. This article shows that by combining the traditional SFM with the frequency-domain analysis (FDA), the effective separation points between the module case and the external cooling setup can be identified in both time and frequency domains, which correspond to the characteristic frequency points in the complex loci of the thermal impedance curves. By extracting the amplitudes at the characteristic frequencies from the complex loci in the FDA, the junction-to-case level coupling thermal resistances can be derived. Both simulation and experimental study have been carried out to verify the concept. The agreement between the two justifies the proposed method.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Design and Performance of High Voltage Chip-Level Series-Connected SiC
           MOSFET Module

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      Authors: Hai Shang;Lin Liang;Yijian Wang;
      Pages: 1757 - 1767
      Abstract: In medium voltage (MV) and high voltage (HV) applications, HV SiC mosfet with a single chip competes with series-connected low voltage (LV) SiC mosfet. The cost of the former is high due to immature process, and the parasitic inductance of the latter is large due to series-connected devices. In this article, a novel chip-level series-connected SiC mosfet module based on planar packaging is proposed to compromise cost and parasitic inductance. Several LV chips are connected in series through metal layers, and then packaged as a whole. Compared with HV module with a single chip, the proposed module has significant advantages in cost. Considering the effects of the buffer layer and direct bonded copper on the parasitic inductance, junction temperature, thermal stress, and electric field, electro-thermo-mechanical simulation is conducted to optimize the structure. Compared with existing series-connected structures, the parasitic inductance of the proposed module is reduced by at least 50.15%. Finally, 6.5 kV chip-level series-connected module with six 1.2 kV SiC mosfet is fabricated and tested. The results show the performance of the proposed module is comparable with that of HV module with a single chip, which means that the application of the proposed module in MV and HV conditions is promising.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Evaluation of the Degradation in Electrothermal Characteristics of IGBTs
           During Thermal Cycling Cocaused by Solder Cracking and Al-Wires
           Lifting-Off Based on Iterative Looping

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      Authors: Yongle Huang;Yifei Luo;Fei Xiao;Binli Liu;Xin Tang;
      Pages: 1768 - 1778
      Abstract: The evaluation of dynamic degradation in electrothermal characteristics of insulated gate bipolar transistors (IGBTs) caused by package fatiguing is critical to the operating safe and reliable application of IGBTs under their long-term servicing. In the present work, the degradation mechanism in electro thermal characteristics of IGBTs caused by package fatiguing (die-attach solder cracking and Al-wires lifting-off) was analyzed, first. An iterative looping consisting of the electrothermal simulation, fatigue damage calculation, and degradation of electrothermal characteristics in IGBTs was proposed based on the physics of failure. Based on that, the degradation in electrothermal characteristics of IGBTs during power cycling (PC) caused by the two fatigue modes was investigated. PC tests were carried out to 1700 V/3600 A IGBT modules under various conditions for verifications. Under six various PC conditions, the maximum of errors is lower than 7%. It indicates well consistence with experiments. The proposed iterative looping directly simulates the degradation of electrothermal characteristics of IGBTs during thermal cycling. It may provide a possibility of evaluating offline or online the important electrothermal parameters of IGBTs (such as Tj and VCEsat) during operating, which is meaningful for diagnosing the safe operating area of IGBTs after long-term servicing.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Improved Double Pulse Test for Accurate Dynamic Characterization of Medium
           Voltage SiC Devices

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      Authors: Haiguo Li;Zihan Gao;Ruirui Chen;Fei Wang;
      Pages: 1779 - 1790
      Abstract: This article presents an improved double pulse test (DPT) for accurate dynamic characterization of the medium voltage (MV) silicon carbide device. The difference between low voltage (LV) and MV DPT setup grounding is first introduced, which results in different measurement considerations. Then, parasitic capacitances in the DPT and their impact on the DPT are discussed considering different grounding points and device connections. Approaches are proposed to minimize the impact of parasitic capacitances on DPT results. In addition, the impact of switching V-I timing alignment on the testing results is discussed, compared to that in the LV DPT; a V-I alignment approach is introduced for the MV DPT. A 10 kV/20 A SiC mosfet-based DPT is taken as an example of the improved DPT, and test results show that it can minimize the impact from parasitic and improve the accuracy of the device switching loss estimation.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • A Passive Thyristor-Based Hybrid DC Circuit Breaker

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      Authors: Jiawei He;Huijie Lyu;Bin Li;Ye Li;Weijie Wen;Daniel Westerman Spier;Eduardo Prieto-Araujo;Oriol Gomis-Bellmunt;
      Pages: 1791 - 1805
      Abstract: DC circuit breaker (DCCB) is one of the most important technologies for safe and reliable operation of dc grid. And the hybrid DCCB (HCB) is obviously promising in high-voltage application area, because it combines both the advantages of mechanical DCCB and solid-state DCCB. At present, insulated gate bipolar transistors (IGBTs) are generally used for configuring the main breaker branch in the HCB. Compared with IGBTs, thyristors have the merits of ability to bear higher surge current, higher reliability, and lower cost, thus being more economical and reliable when used to replace IGBTs. Right now, several topologies of thyristor-based HCBs have been proposed, but the economy, reliability, control complexity, as well as the operation performance, can still be improved. In this article, a novel passive thyristor-based HCB is proposed. Compared with existing IGBT-based HCBs, the proposed HCB has significant advantages on economy and reliability, due to the application of thyristors for replacing IGBTs. In addition, in the proposed scheme, the required thyristors count is reduced and the additional power supply for capacitor precharging is saved, so the investment and control complexity are both cut down. The feasibility and superiorities of the proposed HCB are validated with scaled-down experiment test and 500-kV-level simulation case study.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Analysis of Dead-Time Energy Loss in GaN-Based TCM Converters With an
           Improved GaN HEMT Model

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      Authors: Yi Zhang;Wenzhe Xu;Yue Xie;Teng Liu;Zongheng Wu;Cai Chen;Yong Kang;Han Peng;
      Pages: 1806 - 1818
      Abstract: For gallium nitride (GaN) based triangular current mode (TCM) applications, the dead-time has a significant effect on the switching loss. However, previous GaN high electron mobility transistor (HEMT) models focus on the turn-on/off process without fully considering the effect of the dead-time. Hence, this article analyzes the switching transients under the superfluous and insufficient dead-time and evaluates the dead-time loss with an improved GaN HEMT model. The proposed model improves an existing GaN HEMT model by adding the voltage rising/falling time of the gate driver, the dynamic threshold voltage of Schottky-type GaN HEMTs, and an equivalent gate-drain capacitance obtained from the datasheet. Verified by a GaN-based double-pulse test, the proposed model can more accurately calculate the gate-source voltage and the self-commutated reverse conduction voltage. Verified by a GaN-based TCM Buck converter, the proposed model can predict the dead-time loss well and has higher simulation accuracy for the turn-on process induced by the inappropriate dead-time.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Design and Assessment of a New Active CM Filtering Architecture for PWM
           Inverter-Fed Motor Drive Systems

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      Authors: Kun Zhang;Henry Shu-Hung Chung;Weimin Wu;
      Pages: 1819 - 1830
      Abstract: The stepwise common-mode (CM) voltage at the output of inverters causes electromagnetic interference (EMI) and damage to motor bearings. This article proposed a new output active CM filter (ACF) to compensate for the steep rising/falling edges of CM voltage for EMI reduction and bearing protection. An input ACF is also necessary to attenuate the CM noise injected into the grid. Hence, a holistic assessment of input and output ACFs for inverter-fed motor drive systems has been demonstrated. The motor drive system satisfies the CM EMI standard with this new active CM filtering architecture. Ferrite materials and winding configurations of the CM transformer used in the output ACF have been investigated. Moreover, the relationship between the input and output ACFs has been discussed. This article aims to provide new perspectives and implementation guidelines for the ACFs in motor drive systems.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Submodule Switching-State Based EMI Modeling and Mixed-Mode EMI Phenomenon
           in MMC

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      Authors: Tao Sun;Xuejun Pei;Yue Shan;Jian'guo Pei;Dong Jiang;
      Pages: 1831 - 1843
      Abstract: Modular multilevel converter (MMC) is widely used in high-voltage occasions for its good power qualities and flexible controls. However, the large number of semiconductor switches would lead to an extremely complicated electromagnetic environment. To clarify the detailed conducted electromagnetic interference (EMI) mechanisms of MMC, this article builds an EMI model of MMC considering different submodule switching states. Based on this model, the EMI paths of submodule switching-on and switching-off processes are analyzed. Then, this article analyzes the effects of submodule heatsink connecting patterns on EMI, and explains the mechanisms of mixed-mode (MM) EMI phenomenon that common-mode component brings in extra differential-mode component. Simulation and experiment results verify the proposed EMI mechanisms and MM phenomenon. The conclusions of this article have great reference significance for the EMI research of MMC and other high-voltage converters.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • A Three-Phase Dual-Output T-Type Three-Level Converter

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      Authors: Rutian Wang;Shuai Yuan;Chuang Liu;Dongbo Guo;Xinming Shao;
      Pages: 1844 - 1859
      Abstract: A novel three-phase dual-output T-type three-level converter (DO-T-TLC) topology is proposed in this article. The proposed topology has the dc-link and two sets of three-phase ac voltage output terminals. The topology of DO-T-TLC is introduced. Then, the operating principle of multiplexing switches and the available switching states of converter are analyzed, including current path, output phase voltage level, and blocking voltage of different switching states. The phase disposition pulsewidth modulation scheme with dc offsets is discussed in detail, and the key problems of the modulation scheme under both the common frequency and different frequency operation modes, such as voltage level selection, displacement angle constraint, and modulation index range, are studied. For the imbalance of two series capacitors in the dc-link, the mechanism is first revealed, and then a dc-link capacitor voltage balance method to control the average neutral point current is proposed. When DO-T-TLC is used in different operation modes, the ability and effect of this method to balance capacitor voltages are summarized. A low-power three-phase prototype is built, and the experimental results are given to verify the feasibility of the proposed topology and the effectiveness of the modulation scheme to control the voltage balance.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Ultrafast Protection of Discrete SiC MOSFETs With PCB Coil-Based Current
           Sensors

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      Authors: Aamir Rafiq;Sumit Pramanick;
      Pages: 1860 - 1870
      Abstract: Silicon carbide (SiC) mosfets offer significant advantages in terms of improved efficiency and reduced size of power electronic converters. However, they possess lesser short-circuit withstand time than silicon devices. An ultrafast short-circuit protection scheme for TO-247 packaged SiC mosfets is presented in this article. The protection scheme utilizes printed circuit board (PCB) coils to sense the rate of change of current through SiC mosfets in a half-bridge circuit. The PCB coils are fabricated near a single interconnect trace between the power device and the dc busbar. To ensure minimal intrusion inside the power-loop, the methodology of selecting the minimum trace length for a desired mutual inductance between the coil and the interconnect trace is presented through finite-element analysis. Experimental results for an SiC mosfet subjected to a hard switched fault and a fault under load are presented, and the protection circuit response time under 25 ns is reported. Lastly, the peak current-mode control of a buck converter is implemented using the designed PCB coil-based sensor as current feedback sensor. Therefore, the PCB coil is demonstrated to be an effective alternative for Hall effect and magnetic core-based sensors in current control applications with dc/dc converters.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • High-Gain Bidirectional LCLC Resonant Converter With
           Reconfigurable Capability

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      Authors: Nagesha C.;N. Lakshminarasamma;
      Pages: 1871 - 1886
      Abstract: A reconfigurable gain circuit is proposed for an LCLC resonant converter with bidirectional capability considering wide varying redox flow battery source. A suitable hybrid control scheme for LCLC resonant converter with secondary synchronous rectifier is proposed in this work. The proposed reconfigurable circuit enables to configure secondary bridge as an active voltage doubler, full-bridge circuit during forward power transfer mode and reverse power transfer mode, respectively. The reconfigurability helps significantly to design a transformer with lower secondary turns and achieve desired high gain. The reduced transformer secondary turns result in reduced transformer parasitics. The presence of LCLC resonant tank helps to provide the additional gain; the hybrid control scheme ensures zero-voltage switching turn-on for the primary, and secondary synchronous mosfets throughout the operating range. The proposed converter is analysed using fundamental harmonic approximation. The proposed reconfigurable gain circuit and hybrid control scheme is verified experimentally for an 800 V/1 kW hardware prototype fed from 24 to 54 V input.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • A Family of Interleaved Boost Converters for Battery Discharging in Space
           Applications

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      Authors: Hongyu Zhu;Donglai Zhang;Xiyang Liu;Maoping Zhang;Bowen Zhang;
      Pages: 1887 - 1900
      Abstract: A family of interleaved boost converters and an original systematic derivation method based on the two-phase interleaved inverse-coupled inductor concept are proposed in this article for battery discharging in spacecraft applications. The family, including 14 converters, is generated by interconnecting multiple pulsating voltage cells through the energy storage cells. The basic pulsating voltage cells are derived from an inverse-coupled boost converter, and the energy storage cells include an inductor cell, tapped inductor cell, flyback cell, buck-current-fed cell, and partially current-fed cell. The proposed family of converters achieves high efficiency, step-up power conversion without the right-half-plane zero effect, continuous output current and low side switch driver. The operational principle and small-signal analysis of a representative topology in the proposed family of converters are discussed in detail. Moreover, experimental and simulation results are presented to verify the feasibility and effectiveness of the developed converter. Finally, the characteristics of the proposed family of converters are compared with other state-of-the-art converters.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Rotating Phase Shedding for Interleaved DC–DC Converter-Based EVs
           Fast DC Chargers

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      Authors: Mohammed A. Alharbi;Abraham M. Alcaide;Mohamed Dahidah;Montero-Robina P.;Salaheddine Ethni;Volker Pickert;Jose I. Leon;
      Pages: 1901 - 1909
      Abstract: Fast dc chargers are the key enablers for the massive rollout of electric vehicles due to the reduced charging time. On the other hand, the rapid growth in battery technology with different voltages and charging requirements has imposed additional hurdles on the charger design to meet the efficiency requirements. Multiphase interleaved converters with conventional phase-shedding control improve the efficiency for a wide range of operations. However, they tend to operate certain phases, resulting in uneven thermal stress among the converter phases. This article proposes a rotating phase-shedding control to distribute the switching activities among all phases, enhancing the system's reliability while retaining the efficiency improvement. The proposed technique selects the proper number of active phases based on the required charging profile and periodically swaps them with other phases to even out the stress. The thermal profile is extracted to assess the thermal damage of the power switches. The performance of the proposed approach is evaluated and compared with the conventional phase shedding. The simulation and experimentally validated results confirm that the proposed technique achieves a better even distribution of the thermal damage between the phases compared with the conventional one. This will ultimately extend the lifetime of the system.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Isolated 3-Level DC–DC Converter With Complete ZVS Using
           Magnetizing Inductors

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      Authors: Dakai Wang;Wensong Yu;Greg Mann;Dennis Meyer;Ehab Tarmoom;Steven Chenetz;Xuning Zhang;Kevin Speer;
      Pages: 1910 - 1923
      Abstract: An isolated dc–dc converter with dedicated 3-level modulation is proposed to achieve a 4:1 output voltage range, and complete zero-voltage-switching (ZVS) of all active switches using the magnetizing inductors. The single input 3-level modulation scheme coordinates the phase-shift, duty cycle, and switching frequency to ensure 1) the magnetizing currents are independent of load voltage and current; 2) the output voltage is proportional to the modulation input. As a result, the dual half- and full-bridge modes of the switching network are unified and modeled as a voltage-controlled voltage source, with the same control parameters for both modes of operation. In addition, the magnetizing-to-series inductance ratios of the leading and lagging transformers are increased to 100 and 25 times, respectively. Therefore, the circulating current is low, and the series inductors can be integrated into the transformers. The proposed topology is intended for high-power applications with a wide output voltage range but less input voltage variation. A $text{30},text{kW}$ prototype with a power density of $text{7.2},text{kW}/text{L}$ and an output voltage of $text{165},text{V}$-$text{680},text{V}$ was built and tested to verify the characteristics and feasibility of the proposed H8 topology plus modulation scheme.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Comprehensive Physical Commutation Characteristic Analysis and Test of
           Hybrid Line Commutated Converter Based on Physics Compact Model of IGCT

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      Authors: Zhanqing Yu;Zongze Wang;Chaoqun Xu;Xuan Zhou;Zhengyu Chen;Chunpin Ren;Rong Zeng;
      Pages: 1924 - 1934
      Abstract: In order to mitigate commutation failure of high voltage direct current (HVdc) system, a novel hybrid line commutated converter (H-LCC) based on integrated gate commutated thyristor (IGCT) and thyristor has been proposed. To verify the proposed scheme's effectiveness and correctness, the physics-based compact model of reverse blocking IGCT (RB-IGCT) and physics-based model of thyristor are established in this article. By comparing the features of physics-based model with other simulation methods, it can be observed that the former has obvious advantages. On the basis, a simulation study of proposed H-LCC based on physics compact model of RB-IGCT and physics-based model of thyristor is conducted to analyze the physical commutation characteristics comprehensively, which is verified by equivalent commutation tests. The H-LCC can mitigate commutation failure of HVdc effectively and physics-based model of H-LCC is expected to be applied in the simulation of dc grid equipment and provide reference for commutation characteristics analysis and snubber parameter optimization that need rapid and multiple simulations.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Multiple Output Inverter and Monitoring System for Homogeneous
           Electroporation

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      Authors: Borja López-Alonso;Héctor Sarnago;José M. Burdío;Oscar Lucía;
      Pages: 1935 - 1947
      Abstract: Electroporation is a phenomenon that increases the permeability of cells by applying an electric field. This technique has relevant applications to cancer treatment using both electrochemotherapy and tumor ablation using irreversible electroporation. In order to carry out these treatments, new power converters are needed to apply of output voltages of several kV and output currents of tens of A in pulses of a width of μs. In addition, to achieve safe and relapse-free treatments, it is necessary to generate a controlled and uniform electric field. A challenge in current treatments is to ensure effective treatments despite tissue heterogeneity. In this context, this article proposes a new pulse generator that allows the use of a multielectrode structure that enables the application of a uniform electric field in multiple directions to avoid issues related to tissue heterogeneity. The proposed generator also allows the continuous monitoring of the treatment to adequately control the generator and apply a safer and more effective treatment. An 18-output 1500-V experimental prototype was designed, implemented, and tested using vegetal tissue, proving the feasibility of this proposal.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • A DAB-Based DC Transformer for Multiterminal HVdc Dynamic Simulation
           Platform With Short Circuit Tolerance

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      Authors: Deshang Sha;Xiangshuai Jia;Haipeng Yao;Dong Liu;Huaiguang Gu;
      Pages: 1948 - 1957
      Abstract: The dc transformer (DCT) can be used to achieve a direct connection between various dc bus voltages. A multiwinding dual active bridge (DAB) structure is proposed to be used in that occasion for a dynamic simulation platform. For high voltage side, automatic voltage balance and power-sharing balance can be achieved automatically without mandatory power sharing control. To deal with wide voltage conversion gain application, a multimode modulation with peak current value optimization is proposed. It has the tolerance for the short circuit operation under dc fault. The power transmission can be suppressed rather low during the fault. A 1 kV/1.6 kV 10 kW DCT has been fabricated and applied in a dynamic simulation platform. The bidirectional power flow capability together with the short circuit fault tolerance has been verified through the test.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • A Three-Phase Single-Stage ac/dc Converter Based on Swiss Rectifier and
           Three-Level LLC Topology

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      Authors: Xiang Li;Julu Sun;Liuniu Guo;Mingzhi Gao;Haibing Hu;Ming Xu;
      Pages: 1958 - 1972
      Abstract: LLC resonant converter is widely used due to its soft switching, high power density, and high efficiency. To incorporate the merits of the LLC resonant tank into a three-phase single-stage ac/dc converter, this article proposes a three-phase single-stage ac/dc converter based on Swiss rectifier and three-level LLC topology. It takes advantage of the high-efficiency Swiss rectifier to convert three-phase ac voltages into three variable dc voltages and interface a three-level LLC resonant circuit. With help of the LLC resonant tank, all the high-frequency three-level switches achieve soft switching. To both regulate the output voltage and achieve three-phase power factor correction, the frequency modulation in combination with the duty cycle control strategy is employed by splitting the resonant current into three parts and then forming three phase sinusoidal currents. The proposed converter's detailed operation principles, steady-state characteristics, and design considerations are given. Finally, a 10 kW experimental prototype with three-phase 220 Vac inputs and 500 Vdc output is built to verify the effectiveness and feasibility of the proposed topology and its control strategy.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • A New Low Switching Frequency Control of Regenerative CHB Drive With
           Low-Voltage Ride-Through Capability

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      Authors: Zhituo Ni;Ahmed H. Abuelnaga;Sarah Badawi;Shaoyi Yuan;Mehdi Narimani;Ahmed Sayed-Ahmed;Zhongyuan Cheng;Navid R. Zargari;
      Pages: 1973 - 1983
      Abstract: In conventional medium-voltage high-power cascaded H-bridge (CHB) drive, a three-phase rectifier is adopted in each power cell to provide isolated dc-bus voltage for the output H-bridge. This limits the application of the conventional CHB drive, where regeneration capability is desired. The regenerative CHB drive can be made possible by replacing the diode rectifier with a three-phase IGBT-based active-front-end (AFE) rectifier in each power cell. However, due to thermal constraints in the high-power medium-voltage drives, the first challenge of the regenerative CHB drive is to deal with the extra switching losses introduced by the IGBT devices. Another challenge of the grid-tied regenerative CHB drive is to handle the low-voltage sags in the power grid without triggering unnecessary downtime in transients. In this article, a novel low-switching frequency control strategy is proposed for the AFEs in the regenerative CHB drive with low-voltage ride-through (LVRT) capability. The main harmonic contents generated by the AFEs with the proposed control strategy can be eliminated by the existing phase-shifting transformer in the CHB drives. This allows meeting with IEEE STD 519-2014 requirement with a 60 Hz switching frequency to minimize the extra introduced switching losses in steady state. Moreover, LVRT capability is integrated into the proposed control scheme with reduced current sensor count. Accompanied with videos, the experiments on a seven-level regenerative CHB drive are implemented to validate the feasibility of the proposed control scheme, which can be extended to regenerative CHB drives with any voltage levels.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • $^circ$ +Coordinates+to+Suppress+Common-Mode+Voltage+for+Multilevel+Converters&rft.title=IEEE+Transactions+on+Power+Electronics&rft.issn=0885-8993&rft.date=2023&rft.volume=38&rft.spage=1984&rft.epage=1997&rft.aulast=Xie;&rft.aufirst=Cui&rft.au=Cui+Wang;Wenjun+Zeng;Yunhe+Wang;Changxue+Li;Wanzheng+Duan;Xiaopin+Yang;Yunmin+Xie;">SVPWM Strategy Based on the 45 $^circ$ Coordinates to Suppress Common-Mode
           Voltage for Multilevel Converters

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      Authors: Cui Wang;Wenjun Zeng;Yunhe Wang;Changxue Li;Wanzheng Duan;Xiaopin Yang;Yunmin Xie;
      Pages: 1984 - 1997
      Abstract: This article proposes an optimized space vector pulsewidth modulation (SVPWM) strategy with minimum common-mode voltage (CMV). Compared with earlier SVPWM methods, the proposed optimized strategy is implemented in the 45$^circ$ coordinates. Locating the sector triangle, calculating the duty cycles, and determining the switching sequences require only basic arithmetic operations, which greatly reduces the computational complexity. The switching state with minimum CMV corresponding to the space vector can be calculated directly. The proposed optimized modulation strategy effectively solves the problem that the traditional SVPWM is difficult to be implemented as the number of levels increases. It can be easily extended to any level converters without additional computational burden. Based on the proposed optimized SVPWM strategy with minimum CMV, the SVPWM strategy for eliminating CMV is proposed. The proposed SVPWM strategy for eliminating CMV improves the utilization of the redundant cells and reduces the total harmonic distortion of phase voltages without increasing the difficulty of implementing the SVPWM algorithm. Finally, the proposed two SVPWM strategies are verified with extensive simulations and experiments.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • A High Power Density Wide Range DC–DC Converter for Universal
           Electric Vehicle Charging

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      Authors: Satyaki Mukherjee;Juan M. Ruiz;Peter Barbosa;
      Pages: 1998 - 2012
      Abstract: This article presents a single stage isolated bidirectional DC–DC converter comprising of LCL-T resonant network for universal electric vehicle (EV) charging. Fixed frequency operation along with phase-shift control enables easier design of passive components, while achieving high efficiency across wide output voltage range. Furthermore, to increase the switching frequency and consequently the power density, gallium nitride (GaN) switches are explored in the proposed solution. In order to facilitate use of commercially available 650 V GaN transistors, a multi-level inverter and a reconfigurable rectifier architecture is utilized along with LCL-T resonant network, accommodating an input voltage of 800 V, generated from an universal three phase ac input supply, and an output voltage ranging from 150 V to 950 V catering to large variation of battery voltages from different vehicle manufacturers. The constant input voltage-to-output current gain property of LCL-T network, along with an efficient phase-shift modulation proposed in this paper enable soft switching of all transistors with minimum circulating currents over constant current (CC), constant power (CP), and constant voltage (CV) modes of battery charging. Experimental results are provided for a single-phase DC–DC converter prototype utilizing 650 V GaN transistors operating from an 800 V DC bus and providing a very wide output voltage from 150 V to 950 V at 6.6 kW maximum power at a constant switching frequency of 500 kHz. The prototype achieves two peak efficiency points of 98.2% and maintains $>$ 97% efficiency across the entire output voltage range at a power density of 120 W/in3 (7.3 kW/L).
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • A Hybrid Seven-Level Dual-Inverter Scheme With Reduced Switch Count and
           Increased Linear Modulation Range

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      Authors: Souradeep Pal;K. Gopakumar;Umanand Loganathan;Haitham Abu-Rub;Dariusz Zielinski;
      Pages: 2013 - 2021
      Abstract: This work presents a hybrid seven-level dual inverter scheme with increased linear modulation range. The hybrid inverter structure is formed by supplying the load from primary side by using a cascaded structure of a two-level inverter and H-bridge (HB) and secondary side of the load is supplied by a floating-capacitor-fed two-level inverter. The combination of primary two-level space vector structure (SVS) with secondary two-level SVS and primary three-level SVS of HB form a seven-level SVS that can further be extended to an eight-level hexagonal SVS. This structure then reduced to a 12-sided eight-level SVS to avoid exceeding motor phase voltage rating. Subsequently by using this eight-level SVS in an unique pulsewidth modulation mode, the proposed topology can increase the modulation range linearly from $0.577V_{text{dc}}$ to $0.637V_{text{dc}}$ peak phase fundamental voltage for any load power factor (pf), where dc-link voltage is $V_{text{dc}}$. An 11$%$ increase in modulation range ($0.637V_{text{dc}}/0.577V_{text{dc}}$) is possible devoid of lower order harmonics (predominantly $5{text{th}}$, $7{text{th}}$, $11{text{th}}$, $13{text{th}}$, etc.) in phase voltage for unity pf load in comparison to the conventional six-step operation of two-level and multilevel hexagonal SVS. To balance HB capacitors voltages in this work, a -oncept of indirect space vector redundancy is used. The efficacy of the proposed inverter scheme is verified through various experimental results at different steady-state and transient conditions.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Reconstructed Phase Voltages Based Power Following Control for Three-Phase
           Buck Rectifier Under Unbalanced Phase Voltages and Wide AC Input Frequency
           

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      Authors: Rui Huang;Jianping Xu;Qiang Chen;Xia Guo;Haibin Cao;
      Pages: 2022 - 2031
      Abstract: In wide ac input frequency applications, such as more electric aircraft, ac input frequency of the three-phase buck rectifier varies in the range of 360–800 Hz. In this article, a reconstructed phase voltages based power following control for the three-phase buck rectifier under unbalanced input phase voltages in wide ac input frequency application is proposed. The input phase voltages are reconstructed to get more balanced modulation signals compared with the input phase voltages. The input currents are controlled to be in proportion to the reconstructed phase voltages to mitigate the imbalance of the input currents. The control strategy is simple and easy to be realized in digital. The analysis and design of the proposed control strategy and digital implementation are illustrated. An experimental prototype with 1.5 kW is built. The experimental results show that the sinusoidal input currents can be obtained when input phase voltages are unbalanced in wide ac input frequency application.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • A 3-D Finite Difference Method for Obtaining the Steady-State Temperature
           Field of a PCB Circuit

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      Authors: Guochun Wan;Kaifeng Zhang;Kang Fu;
      Pages: 2032 - 2040
      Abstract: The temperature rise caused by the heat generated by the on-board LED driver module during work will lead to the rise of product failure rate. The thermal analysis of this drive module should not only consider the heat and packaging of the LED itself, but also the influence of other power components. Common commercial thermal simulation software, such as ANSYS ICEPAK or FLOTHEM, usually requires detailed thermal models for such printed circuit board (PCB)-level thermal simulation, and requires a large number of simulation parameter settings and a long simulation time to obtain temperature results that are barely close to the actual. In this article, a 3-D finite difference method is proposed to obtain the steady-state temperature field of PCB circuit. The model can be used to calculate the steady-state temperature field of PCB circuit by setting different component sizes, power, and thermal conductivity. This article uses this method to calculate the temperature field of PCB steady-state working with MATLAB. The experimental measurement of PCB is compared with thermal simulation by ANSYS ICEPAK. It proves that the temperature results obtained by this method are similar to the actual test temperature compared with ANSYS ICEPAK. The time required for calculation is greatly reduced.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Two-Switch Forward Converter With an Integrated Buck Converter for High
           Bus Voltage in Satellites

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      Authors: Jeong-Eon Park;Jung-Kyu Han;Seung-Hyun Choi;Gun-Woo Moon;
      Pages: 2041 - 2051
      Abstract: As satellite missions become increasingly diverse, the power capacity of satellites continues to increase. Accordingly, the weight and loss of the electrical power system of the satellite must be reduced. Thus, a high bus voltage is required for the electrical power system of the satellite. However, most high-power dc/dc converter topologies, such as half-bridge and full-bridge dc/dc converters have leg-structures, which violate the heritage design characteristics of the dc/dc converters for satellites. To solve these problems, a two-switch forward converter with an integrated buck converter is proposed in this article. By integrating the buck converter into the two-switch forward converter, one switch and one diode are eliminated in the proposed converter, and consequently, its cost, weight, and volume can be greatly reduced. Moreover, the zero-voltage switching of the low-side switch can be achieved. Therefore, the proposed converter achieves a high efficiency under the entire load condition compared with conventional converters. The effectiveness and feasibility of the proposed converter were verified with a prototype of 300–330 V input and 600 W (150 V/100 V) output.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Three-Phase Single-Stage Bidirectional CCM Soft-Switching AC–DC
           Converter With Minimum Switch Count

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      Authors: Jaeyeon Lee;Hyeonju Jeong;Tat-Thang LE;Sewan Choi;
      Pages: 2052 - 2062
      Abstract: In this article, a three-phase single-stage bidirectional ac–dc converter with low component count is proposed. The single-stage structure is configured by integrating a three-phase ac–dc converter and a three-phase dual active bridge converter. The power factor correction and bidirectional power control are performed by adjusting the modulation index of sinusoidal pulse width modulation (SPWM) and phase-shift angle between the primary and secondary bridges. The low-frequency components generated by SPWM are absorbed by fundamental blocking capacitors connected in series with transformer windings, resulting in true high-frequency isolation. The proposed converter can achieve soft-switching of all switching devices even in continuous conduction mode. A 110 Vac, 3 kW, 100 kHz prototype is implemented to validate the proposed concept and demonstrated 95.34% peak efficiency.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Design Procedure for Reduced Filter Size in a Buck Converter Using a
           Fourth-Order Resonance Filter

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      Authors: Youssef Kandeel;Séamus O'Driscoll;Cian Ó Mathúna;Maeve Duffy;
      Pages: 2063 - 2073
      Abstract: This article presents a novel design procedure for fourth order and fourth-order resonance (4thRes) output filters, for given buck converter specifications, making components selection a straightforward process. An accurate filter analysis is provided to predict the filter component currents and voltages in both frequency and time domains. Application of the analysis in a design study of a 20 MHz, 5.4 W buck converter shows that the 4thRes filter has the potential to reduce the output passive components for a wide duty cycle range. As compared with a second-order filter at VIN = 6.6 V to VOUT = 1.8 V, total inductance, inductor energy, capacitance, and capacitor energy are 58%, 35%, 45%, and 31% lower, respectively. Air-core printed circuit board (PCB) integrated solenoid inductors are considered for implementation and testing within a prototype converter to show the impact of these filters on the converter performance. The 4thRes filter achieved 3.7% and 3.6% higher full-load efficiency than the second- and fourth-order filters, respectively, and a better load transient performance.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • High Efficiency and High Power Density Partial Power Regulation Topology
           With Wide Input Range

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      Authors: Zongheng Wu;Zhiwei Wang;Teng Liu;Wenzhe Xu;Cai Chen;Yong Kang;
      Pages: 2074 - 2091
      Abstract: Data centers require high efficiency and high power-density dc–dc converter with wide input range and galvanic isolation. To overcome the drawbacks of traditional single-stage LLC and two-stage solutions, a novel partial power regulation topology with wide input range is proposed in this article. The proposed topology delivers the load power through a three-ports LLC-based dc transformer regulated DCX (DCX). A pulsewidth modulation (PWM) converter is cascaded with one of the input ports of the DCX and then in series with the other input port to regulate the output voltage. Since a single transformer and a partial power PWM converter are employed, high power density can be achieved. Furthermore, only a portion of the load power is transferred by the PWM converter, the efficiency sacrifice is reduced. By introducing an appropriate negative current, the zero voltage switching of the PWM is also achieved. Furthermore, when the input voltage approaches the lower or the upper limit, the switching frequency of the PWM regulator can be ultralow. As a result, switching losses and core losses are further reduced. Finally, a prototype with 190—475 V input and 12 V/500 W output is demonstrated, which achieves a peak efficiency of up to 97.2% and a power density of 153 W/in3.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Improved Virtual Space Vector Modulation Scheme for the Reduced Switch
           Count Three-Level Inverter With Balanced and Unbalanced Neutral-Point
           Voltage Conditions

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      Authors: Changwei Qin;Xiaoyan Li;
      Pages: 2092 - 2104
      Abstract: This article presents an improved virtual space vector modulation scheme for the reduced switch count three-level inverter with balanced and unbalanced neutral-point voltage (NPV) conditions. By analyzing the effects of unbalanced NPV conditions on basic voltage vectors, the new virtual vectors are constructed by considering the dc unbalancing coefficient and distribution factor for small vectors simultaneously. To facilitate the calculation of duty cycles, the nonorthogonal coordinate system is employed. In addition, an optimized control scheme is developed to obtain the optimized distribution factor, and the relative durations of P-type and N-type small vectors are adjusted to control the voltages across two dc-link capacitors separately. The satisfactory quality of output currents is maintained with both balanced and unbalanced NPV conditions. The feasibility of the proposed scheme is verified by simulated and experimental results.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • A Zero-Transient Dual-Frequency Control for Class-E Resonant DC–DC
           Converters

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      Authors: Andrea Celentano;Fabio Pareschi;Riccardo Rovatti;Gianluca Setti;
      Pages: 2105 - 2114
      Abstract: In this article, a dual-frequency control method for regulating the output power in class-E resonant dc–dc converters has been introduced. As in the standard on–off control or other recently proposed dual-frequency controls, the approach is based on the ability of the converter to alternately operate in a high- and a low-power state. The proposed solution has a twofold advantage: on the one hand, soft-switching capabilities (i.e., zero-voltage and zero-voltage-derivative switching) are preserved in both operating states; on the other hand, it is possible to reduce to zero the transient time required to switch from one state to the other one. The most straightforward consequence is the possibility to increase to very large values the frequency at which the two operating states are switched, up to the same order of magnitude as the main switching frequency of the converter. In this way, the additional ripple introduced by the proposed dual-frequency control can be decreased to a negligible value. The approach has been validated by measurements on a prototype operating between 4 and 8 MHz and in which it has been possible to increase the control frequency up to 500 kHz.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Compact Integrated Transformer – Grid Inductor Structure for E-Capless
           Single-Stage EV Charger

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      Authors: Ramadhan Muhammad Hakim;Huu-Phuc Kieu;Junyeong Park;Tat-Thang LE;Sewan Choi;Byeongseob Song;Hoyoung Jung;Bokyung Yoon;
      Pages: 2115 - 2126
      Abstract: This article proposes a planar magnetic integration technique that combines the grid inductors and transformer in the single-stage E-capless electric vehicle charger into one core. The proposed integration technique reduces the number of magnetic components; therefore, the cost, total magnetic core loss, and volume can be significantly reduced. Using the integrated structure, the overall converter power density increases up to 11.1% compared to the nonintegrated one. This article also presents a detailed analysis of the optimal printed circuit board (PCB) winding arrangement considering both ac resistance and winding stray capacitance. Due to the high dc resistance of PCB winding, Litz wire was also considered for the proposed integrated structure. The effectiveness of the proposed structure was validated by implementing it on a 3.7-kW prototype of a single-stage ac–dc converter. Results show that the prototype with the proposed integrated structure achieved higher efficiency with both PCB winding and Litz wire. Peak efficiency of 97.17% and 6.55-kW/L power density were achieved.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Bidirectional Buck–Boost Converter With Reduced Power Loss and No
           Right-Half-Plane Zero

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      Authors: Yong Zhou;Junwen Li;Xun Liu;Yanqi Zheng;Ka Nang Leung;
      Pages: 2127 - 2142
      Abstract: This article presents a novel hybrid bidirectional buck–boost converter (HBBC) for lithium-ion battery management. Unlike the conventional four-switch buck–boost converter (FBBC), whose power efficiency is greatly limited at heavy loads mainly due to high conduction loss from a high dc resistance (DCR) inductor, the proposed HBBC adopts assisted capacitive paths to reduce the current stress on the main inductive path. Thus, the conductive loss of inductor's DCR is greatly reduced in both the buck and boost modes. To verify the effectiveness of the proposed structure, detailed analyses on both the loop performance and conduction loss are provided. Compared with FBBC, the conversion efficiency of the proposed HBBC is increased by 23.3% in the boost mode, and the peak efficiency is up to 97.8% with an adopted inductor with a DCR of 270 mΩ.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • A Novel Bidirectional Wider Range of Boost-Buck Three-Level LCC Resonant
           Converter as an Energy Link

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      Authors: Zhongyi Zhang;Xiaosen Xiao;Wei You;Haibin Li;Tao Jin;
      Pages: 2143 - 2155
      Abstract: In order to maintain different voltage levels between the front and rear dc terminal bus derived from new energy industry, a novel bidirectional wider range of boost-buck three-level LCC resonant converter as an energy link is proposed by combining the LCC resonant tank module with a particular three-level coupling cascaded neutral point clamping active bridges, which is composed of two three-level neutral point clamping bridge arms. Furthermore, the converter can, respectively, establish forward LCC and backward SRC working modes to maintain unified wider bidirectional voltage gain range between the input and output by asymmetric structure of LCC resonant tank module that boost-voltage is enabled by equivalent principle of conventional LCC resonant converter and buck-voltage is enabled by equivalent principle of conventional series resonant converter, while, a unified bidirectional boost-buck voltage gain matching control strategy is designed with an optimization about parameters of LCC resonant tank module under realizing of zero voltage switching-on and reducing of reactive power losses. Finally, according to the simulation platform and experimental prototype, it can be shown that the practical voltage gain is closed to the theoretical designed gain and converter has good dynamic performances after realizing of soft-switching in each mode.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Medium Frequency Output Impedance Limits of Switched-Capacitor Circuits

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      Authors: Dengke Zheng;Yuhang Yang;Shiming Hu;Yan Deng;
      Pages: 2156 - 2168
      Abstract: As an intrinsic power loss of switched-capacitor circuits (SCCs), capacitor charge-sharing loss reduces the system efficiency. In this article, the approach based on q-u curves of capacitors is proposed to calculate capacitor charge-sharing loss precisely. By considering both capacitor charge-sharing loss and conduction loss, the output impedance of an SCC with a finite output capacitance can be modeled accurately in medium switching frequency. Compared with the previous modeling techniques, the proposed modeling method called RLSL not only counts the output capacitor effect but also applies to a wide range of well-posed switched capacitor circuits. Several high-order SCCs are taken as examples to validate the accuracy of RLSL via simulations and experiments and it could be corroborated that RLSL can predict the output impedance precisely with the change of switching frequency, output capacitor, and duty cycle in the mid-band.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • A High Efficiency and Wide Voltage Gain sLC_LCC DC–DC Converter With SiC
           Devices

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      Authors: Mengying Chen;Bo Chen;Ping Wang;Yifeng Wang;Mingzhi Zhang;
      Pages: 2169 - 2180
      Abstract: A novel sLC_LCC resonant dc–dc converter is proposed in this article. With the combination of a notch filter and a new sLC excitation structure of the transformer, wide and fast gain characteristics are obtained. With the frequency modulation, the notch filter structure helps the converter realize a wide output voltage range adjustable from zero theoretically. Besides, the fast voltage gain regulation capacity is achieved in a narrow frequency range with the sLC excitation structure. In the text, topology structure, operation principle, and characteristics analysis are illustrated in detail. For numerous passive components, an effective design method is necessary to guide parameter determination. And a detailed parameter design process is discussed. With the selected parameters, the soft-switching feature is realized. Finally, a 500 W experimental prototype is fabricated to verify the feasibility and effectiveness of theoretical analysis. The converter achieves 59.3–16.3 V output voltage regulation ability in a narrow frequency range (86 kHz, 189 kHz) under the condition of power 500 W and input voltage 375 V. High efficiency is maintained in the full load range, and the maximal efficiency of the converter reaches 97.7% at 99.5 kHz.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • A Single-Switch Continuous Input Current Buck–Boost Converter With
           Noninverted Output Voltage

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      Authors: Mukkapati Ashok Bhupathi Kumar;Vijayakumar Krishnasamy;
      Pages: 2181 - 2190
      Abstract: In this article, a single-switch continuous input current (CIC) buck–boost converter with noninverted output voltage is proposed. The proposed converter utilizes capacitor and inductor along with three diodes in conjunction with a quadratic boost converter to adopt its CIC feature. The features of high voltage gain, single active power switch, less ripple CIC, and noninverted output voltage make the proposed converter suitable for renewable and industrial applications. In addition, it provides a wide operating voltage gain with optimum component count, which is higher than the conventional buck–boost converter. Furthermore, it has low voltage stress across the power switch with comparable converters. To elevate the importance of the proposed converter, a detailed comparison analysis has been carried out considering voltage stress, voltage gain, effectiveness index, and component count. The operating principle and steady-state analysis in continuous conduction mode and discontinuous conduction mode of the proposed converter are discussed in detail. To validate the theoretical analysis and performance of the proposed converter, a prototype has been developed and tested in laboratory.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Single-Phase GaN-Based T-Type Totem-Pole Rectifier With Full-Range ZVS
           Control and Reactive Power Regulation

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      Authors: Jingjing Sun;Liyan Zhu;Ruiyang Qin;Daniel J. Costinett;Leon M. Tolbert;
      Pages: 2191 - 2201
      Abstract: This article proposes a high-efficiency single-phase GaN-based rectifier with reactive power transfer for use in front-end power supplies as an efficient alternative to centralized reactive power compensation. A full-range zero-voltage switching (ZVS) modulation for both unity power factor (PF) operation and nonunity PF operation is proposed for the GaN-based rectifier in critical conduction mode (CRM) operation. A frequency limitation method is also developed to limit the peak frequency during the ac current zero-crossing. Also, a GaN-based T-type totem-pole rectifier is proposed to overcome the control challenge in CRM during the ac voltage zero-crossing. Meanwhile, a digital-based control scheme is developed to implement ZVS operation and reactive power regulation. The proposed rectifier and ZVS control have the advantages of simple topology, high efficiency, straightforward control implementation, and capability of flexible reactive power regulation. A 1.6-kVA prototype of the GaN-based CRM T-type totem-pole rectifier is built and demonstrated with full-range ZVS operation, 98.9% full-load efficiency, and flexible reactive power regulation with smooth dynamic response.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • A Novel Filter With High Harmonics Attenuation and Small Dimension for
           Grid-Connected Inverter

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      Authors: Kenta Koiwa;Harutaka Takahashi;Tadanao Zanma;Kang-Zhi Liu;Kenji Natori;Yukihiko Sato;
      Pages: 2202 - 2214
      Abstract: Passive power filters are indispensable for grid-connected inverters (GCIs) to eliminate current harmonics. However, typical filters require large inductance, which not only increases the filter dimension and costs but also leads to slower current response and a high voltage drop across the filter. This article proposes a novel filter called LCTCL filter, which effectively attenuates harmonics with small inductance. In addition, this article presents a controller synthesis to the GCI with LCTCL filter without an additional resistor. We demonstrate the effectiveness of the proposed LCTCL filter through comparative analysis with typical filters via simulations and experiments. We clarify that the proposed LCTCL filter has excellent features in terms of filter dimension, frequency characteristics, robustness for parameter variations, harmonic suppression, and total harmonic distortion.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Comprehensive Analysis and Evaluation of DC-Link Voltage and Current
           Ripples in Symmetric and Asymmetric Two-Level Six-Phase Voltage Source
           Inverters

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      Authors: Wesam Taha;Peter Azer;Amirreza Poorfakhraei;Sumedh Dhale;Ali Emadi;
      Pages: 2215 - 2229
      Abstract: Multiphase drives (MPD) in general and six-phase in particular have been gaining popularity in many industries, which calls for a proper multiphase inverter (MPI) design. For voltage source inverter (VSI)-fed drives, the knowledge of voltage and current stresses on the dc-link are imperative for input capacitor sizing. To this end, the voltage and current stresses on the dc-link capacitor in two-level six-phase VSIs are examined thoroughly in this article for two configurations of load/winding spatial distribution: symmetric and asymmetric. First, the harmonic spectrum of the input dc current of each inverter is analyzed in detail by benchmarking them against the conventional three-phase VSI, to precisely establish the dc-capacitor requirement reduction in six-phase counterparts. Second, analytical formulae for the dc-link capacitor voltage ripples are derived for both configurations. Third, simple formulae for dc-capacitor sizing for six-phase VSIs with different load configurations are provided. The accuracy of the derived formulae is verified by simulation and experimental testing at various power factors and modulation depth. It is found that six-phase VSI supplying symmetric and asymmetric loads reaps 10% and 7% lower dc-link current ripples, respectively. Hence, six-phase symmetric loads yield the smallest capacitor size.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Design of Double Staggered Parallel Bearingless Motor Drive System

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      Authors: Xucong Bao;Xiaolin Wang;Qiang Ding;Tengrui Shi;
      Pages: 2230 - 2239
      Abstract: To make bearingless motors (BMs) more competitive, it is imperative to reduce the cost while ensuring high performance. In this article, the driving system of the BM is optimized from the perspectives of the inverter topology and the control strategy. A dual-hybrid vector control driving scheme of the BM based on the double staggered parallel topology is proposed for the control performance and cost. Meanwhile, the levitation/torque stagger phase shift is adopted to lower the root-mean-square value of the dc-link current. The proposed driving scheme is compared with the traditional vector scheme based on a full-bridge topology on a bearingless pump system. It turns out that the two driving schemes are similar in current, speed, and rotor radial displacement fluctuation. The proposed scheme shows the advantages of simpler system structure and lower cost, so it is deemed as an attractive driving scheme for the BM.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Layout-Dominated Dynamic Current Balancing Analysis of Multichip SiC Power
           Modules Based on Coupled Parasitic Network Model

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      Authors: Yuxin Ge;Zhiqiang Wang;Yayong Yang;Cheng Qian;Guoqing Xin;Xiaojie Shi;
      Pages: 2240 - 2251
      Abstract: Multichip silicon carbide (SiC) power modules with Kelvin-source connections are commonly used in applications requiring large capacity. As a result of the parasitic effect induced by the interconnections in module packaging, the dynamic current mismatch among paralleled dies limits the available capacity of power modules. This article presents a general analysis on the mechanism of layout-dominated dynamic current balancing in multichip SiC power modules, utilizing a coupled parasitic network model. Focusing on the interrelation of parasitic parameters in the power module, a coupled parasitic network model is developed specially for switching transients, and the dynamic current balancing equations are derived. For the multichip power modules with two different layouts, the parasitic parameters pertaining to the proposed model are extracted by the finite-element analysis (FEA). The acquired parasitic parameters considering magnetic coupling are utilized to calculate and verify the dynamic current balancing equations. Moreover, based on these parasitic parameters, the electromagnetic coupling simulation is performed to evaluate the dynamic current sharing. Furthermore, for the validation of the proposed model and equations, experiments are conducted with the fabricated power module prototypes.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Smooth Pulse Number Transition Strategy Considering Time Delay in
           Synchronized SVPWM

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      Authors: Joon-Seok Kim;Do-Hyeon Kim;June-Hee Lee;June-Seok Lee;
      Pages: 2252 - 2261
      Abstract: In high power motor drive systems, synchronized space vector pulsewidth modulation (synchronized SVPWM) is widely used to guarantee stable control performance. Synchronized SVPWM has a characteristic that the switching frequency varies abruptly when the pulse number transitions. This article proposes a pulse number transition point at which the phase difference is minimized to remove the phase difference of the sampling point that appears during synchronized SVPWM control. In addition, for a smooth pulse number transition of synchronized SVPWM, a compensation method for the magnitude and phase error of the inverter output voltage due to the time delay and a method of removing the existing phase difference without using a phase-locked loop are proposed in consideration of the characteristic of changing switching frequency. The validity and the implementation of the proposed method are verified by experimental results using a high-power inverter driving 332 kW interior permanent magnet synchronous motor (IPMSM).
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Virtual Current Constraint Based Segmented Trajectory Control Strategy for
           Flux-Weakening Operation of SPMSM Drives

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      Authors: Hongzhe Wang;Chun Gan;Kai Ni;Zhiyue Yu;Ronghai Qu;
      Pages: 2262 - 2274
      Abstract: This article proposes a virtual current constraint based segmented trajectory control strategy for surface-mounted permanent-magnet synchronous motor drives, to improve the transient performance under the flux-weakening operation. In the conventional scheme, the operating points (OPs) are arranged on the current constraint circle during the speed-rising process to provide the maximum electromagnetic torque. After the target speed is reached, there still exists an inevitable transition process that moves OP from the current constraint circle to the steady-state operating point (SSOP), leading to the speed overshoot, oscillation, and prolonged settling time. To solve this issue, a variable virtual current constraint is proposed to replace the fixed one. Based on the developed virtual current constraint, a novel operating point trajectory is designed, where SSOP and the target speed can be reached simultaneously without extra transition processes. Furthermore, to generate the virtual current constraint, a dual-variable based constraint method is put forward and applied to the output limitation of the speed controller. Compared to the conventional schemes, the transient performance can be significantly improved, where the speed overshoot and oscillation are eliminated, and the settling time is greatly shortened. Simulations and experiments are carried out to validate the effectiveness of the proposed scheme.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • A Novel Direct Torque Control Strategy of Two-Level Voltage Source
           Inverters for Eliminating Common-Mode Voltage Spikes Caused by Dead-Time
           Effect

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      Authors: Weitao Deng;Xiuyun Zhang;Wenwu Xie;
      Pages: 2275 - 2284
      Abstract: The traditional direct torque control (DTC) of two-level voltage source inverter-fed motor system can achieve evident reduction of common-mode voltage (CMV) if zero vectors are not used, as the amplitude of the CMV of the zero vector is much larger than that of the active vector. However, due to the influence of dead-time effect, zero vectors can still be generated during inverter commutation, resulting in CMV spikes. To eliminate the CMV spikes caused by dead-time effect, a novel DTC strategy is proposed in this article. Through the analysis of the voltage vector during the dead-time of the commutation process, the process of looking up the DTC switching table is modified, and a transient vector is inserted when necessary, so that no zero vector is generated during commutation. The proposed DTC strategy eliminates CMV spikes in a look-up table way, so that the simple control structure of traditional DTC is maintained, while neither modification of hardware circuit nor detection of current polarity are required. Experiments verified the effectiveness of the proposed strategy.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Decoupled Fault-Tolerant Model Predictive Current Control for Dual
           Three-Phase PMSMs With Harmonic Compensation

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      Authors: Jia Cui;Jinghua Ji;Wenxiang Zhao;Tao Tao;Linsen Huang;Hongyu Tang;
      Pages: 2285 - 2294
      Abstract: This article proposes a decoupled fault-tolerant model predictive current control for a dual three-phase permanent magnet synchronous motor with harmonic compensation. The harmonics caused by nonsinusoidal back electromotive force can be well controlled under the open-circuit fault scenario by designing a harmonic closed-loop scheme. First, a decoupled predictive model and fault-tolerant voltage vectors are deduced based on a reduced-dimension matrix, which can eliminate the coupling issues between the harmonic and fundamental subspaces. Afterward, a uniform harmonic-free virtual vector is constructed by rearranging the irregular voltage vectors. More importantly, a virtual null vector is designed in the scheme, where the virtual null vector is effective in the harmonic subspace and has no components in the fundamental subspace. So, the harmonics can be further controlled without affecting torque and flux generation. Extensive experimental results verify the effectiveness of the proposed method.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • A Novel Four-Leg Inverter Topology for Dual Three-Phase PMSM

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      Authors: Zicheng Liu;Song Shi;She Yan;Wei Sun;Dong Jiang;Ronghai Qu;
      Pages: 2295 - 2306
      Abstract: This article proposes a novel four-leg inverter topology to drive the dual three-phase permanent magnet synchronous motor (DTP-PMSM) with 180° phase shifting. Without access to the midpoint of dc bus capacitors, the proposed four-leg inverter can not only drive the DTP-PMSM with the same torque capability as the conventional six-leg inverter but also avoid the voltage fluctuations of the capacitors in the conventional four-leg inverter. Then, two kinds of pulsewidth modulation methods are given and compared for the proposed topology. The first one is the direct extension of the space vector modulation (SVM) of the four-switch inverter, denoted as SVM1, and the second one is to construct space voltage vectors utilizing almost all the switching states of the four-leg inverter, denoted as SVM2. Experimental results verify the feasibility of the proposed four-leg inverter topology and demonstrate the better harmonic performance of SVM2 compared with SVM1.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • 100 kHz Large-Signal Bandwidth GaN-Based 10 kVA Class-D Power Amplifier
           With 4.8 MHz Switching Frequency

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      Authors: Pascal S. Niklaus;Johann W. Kolar;Dominik Bortis;
      Pages: 2307 - 2326
      Abstract: Power amplifiers (PAs) are widely used, for example, to emulate the behavior of the power grid or electric machines under critical operating conditions, to measure the impedance of the power grid, or to generate specific impedance profiles in power-hardware-in-the-loop (P-HIL) tests. To accurately emulate dynamic effects and to characterize power electronic systems featuring wide-bandgap power semiconductors, PAs with very high output voltage quality and ever higher bandwidth (BW) at full output power are required, motivating the development of ultrahigh bandwidth power amplifiers (UHBW-PAs). While linear UHBW-PAs achieve very high signal fidelity and BW, they suffer from a tremendously bad efficiency, demanding large cooling effort and resulting in uneconomical operation, particular at high power levels and/or during long-term tests. Therefore, this article investigates possibilities for a switch-mode realization of UHBW-PAs with significantly higher efficiency and power density compared to existing solutions. There are two key concepts, namely series- and parallel-interleaving of multiple switching and/or converter cells, that allow to increase the effective switching frequency relevant to output filtering without increasing the individual device switching frequency that determines the per device switching losses. This article analyzes comprehensively the advantages and disadvantages of a combination of series- and parallel-interleaving in terms of losses, volume and complexity scaling. Finally, a UHBW-PA with $mathbf {10}$ kVA output power (single-phase), a nominal rms output voltage of $mathbf {230}$ V, a full-power BW of $mathbf {100}$ kHz, very high output voltage quality (third and fifth harmonic $mathbf {< 2.5}$ V and $mathbf {< 1.2}$ V, respectively), an efficiency $mathbf {>95%}$, a power density of $mathbf {25}$ kW/dm$mathbf {^{3}}$ ($mathbf {410}$ W/in$mathbf {^{3}}$), and a switching frequency of $mathbf {4.8}$ MHz is presented. A hardware demonstrator is built and extensive measurements verify the system performance and confirm the calculation from the initial analyses with loss models.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Predictive Trajectory Control Strategy for Permanent Magnet Synchronous
           Motor Drives Based on Deadbeat Predictive Flux Linkage Control Method

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      Authors: Xin Sun;Yiwei Tang;Xi Xiao;Yulong Xie;
      Pages: 2327 - 2338
      Abstract: Deadbeat predictive controller features a two-sample step response with the existence of one-sampling-period digital delay in a motor drive. However, voltage deficiency is common during abrupt torque change and it inevitably degrades the dynamic performance. In this article, a novel predictive trajectory control strategy with improved dynamic performance is presented for permanent magnet synchronous motor drives. The predictive trajectory controller is developed based on a deadbeat predictive flux linkage controller, and it aims to achieve fast current transient response considering the voltage and current constraint. With the control scheme, deadbeat response is achieved for the case of sufficient voltage margin, and transient performance is optimized for the case of insufficient voltage margin. Solution of the optimization problem is visualized with a geometrical description and analyzed in different spaces. In addition, the trajectory optimization is combined with dynamic overmodulation algorithm to simplify the computation and save the code execution time. Experimental results are finally provided to validate the excellent performance and low computational cost of the proposed control scheme.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Online Adaptive Current Vector Adjustment for Deep Flux-Weakening Control
           of IPMSM

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      Authors: Soroush Ahooye Atashin;Hossein Abootorabi Zarchi;Gholamreza Arab Markadeh;
      Pages: 2339 - 2350
      Abstract: This article presents a novel online adaptive and accurate deep flux-weakening (FW) control for interior permanent magnet synchronous machine (IPMSM) drives. Based on the fundamental equations of IPMSM, the proposed online current vector adjustment in conjunction with the adaptive torque angle control loop contributes to improving model-based existing literature in two aspects. First, current vector control is constructed on the proposed flexible current vector recognition algorithm, which can be applied for motoring and generating modes. The optimum reference current vector for the FW region is analytically obtained using electrical speed as a feedback signal instead of using voltage feedback. Second, the proposed adaptive gain for the torque angle control loop is obtained using the small-signal approach to overcome the nonlinear effects in deep FW and improve dynamic performance. The effect of adaptive gain is compared using a bode diagram and an experimental test. Also, the stability of the proposed control scheme under parameter variations is maintained and shown by numerical and experimental analyses. The running of the IPMSM with the proposed control provides a smooth transition between regions, including maximum torque per ampere, FW, and deep FW applicable for EVs application. The experimental results confirm the performance of the proposed control strategy.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Flux-Weakening Controller Design of Dual Three-Phase PMSM Drive System
           With Copper Loss Minimization

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      Authors: Senyi Liu;Zaixin Song;Yuxin Liu;Yong Chen;Chunhua Liu;
      Pages: 2351 - 2363
      Abstract: The performance of flux-weakening controllers in the multiphase permanent magnets (PM) machines depends on the accurate fundamental voltage limit derivation, and the minimal copper loss design in the flux-weakening operation region has not been well discussed. In this article, the accurate fundamental voltage limit with considering harmonic current suppression is derived at first. Then, two control concepts are addressed, and the corresponding flux-weakening control strategies are designed with the gradient descent method. In the first control strategy, both the fundamental and harmonic voltage vectors are feasible, resulting in the larger amplitude of the phase currents. The second control strategy obtains higher bus voltage utilization by an additional transition stage. At the same time, the harmonic currents cannot be further suppressed in the flux-weakening operation region. Third, the copper loss per electrical cycle is calculated, and a switching scheme is designed to obtain lower copper loss in the flux-weakening operation region. Finally, both strategies are successfully implemented in a dual three-phase PMSM. Moreover, the proposed switching scheme obtains minimal copper loss in the whole flux-weakening operation region.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Cybersecurity of Smart Inverters in the Smart Grid: A Survey

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      Authors: Yuanliang Li;Jun Yan;
      Pages: 2364 - 2383
      Abstract: The penetration of distributed energy resources (DERs) in smart grids significantly increases the number of field devices owned and controlled by consumers, aggregators, third parties, and utilities. As the interface between DER and power grids, DER inverters are becoming smarter with various grid-support functions and communication capabilities. Meanwhile, the cybersecurity risks of smart inverters are also on the rise due to the extensive utilization of information and communication technologies. The potential negative impacts of cyberattacks on smart inverters have attracted significant attention from scholars and organizations. To advance the research on smart inverter cybersecurity and provide insights into its technical achievements, barriers, and future directions, this article will give a comprehensive review of critical attacks and defense strategies for smart inverters and inverter-based systems like microgrids. We start this survey with an overview of the smart inverter introduction, including device- and grid-level architectures, grid-support functions, and communication protocols. We then review various cyberattacks and defense strategies in different categories and scenarios tailed with discussions including their feasibility and remaining gaps. Finally, we discuss the opportunities and challenges of emerging technologies that can secure smart inverters. We hope this survey can inspire efforts to close research gaps and develop more mature cybersecurity solutions for smart inverters in the smart grid.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Dynamic Voltage Equalization Control of D-STATCOM Under Unbalanced Grid
           Faults in a Low-Voltage Network

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      Authors: Xuefeng Wang;Li Peng;
      Pages: 2384 - 2397
      Abstract: Unbalanced grid faults are very harmful to the network operation. Distributed static synchronous compensator (D-STATCOM) can help to support the grid voltage by injecting the reactive power into the inductive power grid. However, this approach turns to be ineffective for a low-voltage grid, where the network impedance is mainly resistive. In this article, a dynamic voltage equalization control (DVEC) scheme is proposed to suppress the negative sequence voltage, and therefore, reduce the voltage unbalance during the faults in the resistive network. This effect is achieved through transferring proper active power from the negative sequence channel to the positive sequence channel. And the dual-sequence active currents are controlled by DVEC without exchanging extra active power with the grid except the little circuit loss compensation. By flexibly adjusting the control parameter of DVEC, current peak and active power oscillation can be limited within a preset range, respectively, during the process of maximizing the voltage control. As a result, the DVEC scheme can ensure the safe operation of D-STATCOM and the stability of the power grid. Moreover, experimental results are reported to validate the correctness and effectiveness of the proposed scheme.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Coordinated DC Interruption Method Based on Magnetic Coupling
           Current-Limiting and Dissipation

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      Authors: Zhizheng Gan;Zhanqing Yu;Zipan Nie;Lu Qu;Xin Yan;Yulong Huang;Rong Zeng;Huaiguang Gu;
      Pages: 2398 - 2407
      Abstract: A flexible dc grid is important for supporting large-scale new energy integrations. To ensure the stable operation of the dc grid, a dc circuit breaker (DCCB) is needed for fault isolation. At present, the cost of DCCBs is high, and the breaking capacity is limited. This limitation can be effectively solved through the coordination of fault current limiters (FCLs) and DCCBs. In this article, a coordinated interruption topology of an magnetic coupling FCL (MCFCL) and hybrid DCCB is proposed. A coordinated interruption strategy based on magnetic coupling current-limiting and energy dissipation is proposed to improve the dynamic performance of the FCL and reduce the energy dissipation and breaking time of the DCCB. A two-stage mathematical model of coordinated interruption is established, and its control principle is analyzed. Furthermore, the influence of the inductance and resistance of the MCFCL secondary side, coupling coefficient and rated voltage of the arrester on the coordinated interrupting process is researched. On this basis, parameter optimization and economic analysis are carried out. Finally, a scaled test for the coordinated interruption of the DCCB and MCFCL was carried out, which verifies the feasibility of the coordinated interruption strategy based on magnetic coupling current-limiting and energy dissipation.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Grid Impedance Detection Based On Complex Coefficient Filter and
           Full-order Capacitor Current Observer for Three-phase Grid-connected
           Inverters

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      Authors: Kaixin Wang;Yong Yang;Mingdi Fan;Yuhang Tang;Haoyang Li;Rong Chen;Jiefeng Hu;Weibo Zeng;Jose Rodriguez;
      Pages: 2408 - 2420
      Abstract: This article proposes a new grid impedance detection method incorporating the complex coefficient filter (CCF) with full-order capacitor current observer for a T-type three-level grid-connected inverter controlled by the inverter output current feedback. Compared with conventional CCF impedance detection algorithms, the proposed method reduces the number of current sensors and detects the grid impedance accurately. First, based on the sampled inverter output current and grid-connected voltage signals, the grid-connected current is estimated. Then, the CCF method is used to extract harmonics from the grid-connected current and voltage signals to calculate the grid impedance. Finally, the correctness of the full-order capacitor current observer is verified by simulation and the feasibility and effectiveness of the proposed algorithm are verified experimentally based on a laboratory prototype.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Discrimination Between Eccentricity and Interturn Faults Using Current or
           Voltage-Reference Signature Analysis in Symmetrical Six-Phase Induction
           Machines

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      Authors: Alejandro G. Yepes;Davide S. B. Fonseca;Hugo R. P. Antunes;Oscar López;Antonio J. Marques Cardoso;Jesús Doval-Gandoy;
      Pages: 2421 - 2434
      Abstract: Two common defects in induction machines (IMs) are eccentricity and interturn faults, which should be diagnosed to prevent performance degradation and further damage. A popular fault-detection approach is the current signature analysis (CSA), because of its simplicity and nonintrusiveness. Under closed-loop control, it is combined with analogous voltage-reference (VR) signature analysis (VRSA). However, by using these methods in three-phase IMs, it is difficult to discriminate between these faults, which cause similar symptoms. Multiphase machines provide remarkable advantages such as inherent tolerance to open-phase faults. Six-phase IMs are particularly attractive since they allow adopting three-phase converters. Among them, those with symmetrical spatial arrangement of the stator phases offer superior fault tolerance. Nonetheless, the distinction between eccentricity and interturn failures in these IMs has not been addressed so far. This article studies the discrimination between eccentricity and interturn faults in symmetrical six-phase (S6) IMs by CSA or VRSA. It is shown that, conversely to three-phase IMs and most other multiphase IMs, in S6 ones, these two types of failures can be easily distinguished: interturn faults considerably alter the currents or VRs in the so-called $boldsymbol{x}$-$boldsymbol{y}$ plane, whereas eccentricity leads to current/voltage symptoms only in the $boldsymbol{alpha} _{mathbf{1}}$-$boldsymbol{beta} _{mathbf{1}}$ plane. Experimental results confirm the theory.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Understanding Inherent Implication of Thermal Resistance in Double-Side
           Cooling Module

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      Authors: Lubin Han;Lin Liang;Ziyang Zhang;Yong Kang;
      Pages: 2435 - 2445
      Abstract: The double-side cooling (DSC) packaging becomes more and more popular with the great demands of high power and fast speed, especially for silicon carbide metal oxide semiconductor field effect transistors. Measurements and modeling of thermal resistance are critical for thermal management of DSC module. However, the thermal resistance of DSC module is still unclear due to the asymmetric dual thermal paths. In this article, a clear understanding of thermal resistance of DSC module measured by transient dual-interface method (TDIM) is explained. The thermal impedance of DSC module is analyzed through time- and frequency-domain response of the DSC thermal model. The cooling conditions in TDIM have no influence on the measured thermal resistance of DSC module. The measured thermal resistance from junction to top case (or bottom case) is half of the actual value. The important conclusions are verified by transient simulations and experiments. Based on the results, a new definition of thermal resistance of DSC module is proposed for exact evaluation of thermal resistance and reliability.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Frequency-Domain Thermal Modeling of Power Modules Based on Heat Flow
           Spectrum Analysis

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      Authors: Mengqi Xu;Ke Ma;Quan Zhong;Marco Liserre;
      Pages: 2446 - 2455
      Abstract: Many efforts have been devoted to describe the multi-timescale thermal dynamics of power modules and frequency-domain modeling is a relatively new approach. Unfortunately, only the frequency-domain response of thermal impedance has been studied in recent works, so the existing models can only describe the temperature behaviors of semiconductors. In the reality, it is not only the temperature of semiconductors which is important but also of other parts of the package. In this article, a novel perspective to study the thermal dynamics by analyzing heat flow behaviors is proposed. Frequency spectrum analysis in finite-element method simulation has been first used in this article, and it reveals that heat flow of the power semiconductor device behaves as a multi-layer low-pass filter (LPF). As a result, a novel modelling method of heat flow with a 7order-3frequencies LPF has been developed in this article and it can provide a comprehensive description of heat flow behaviors for power modules at full bandwidth. Meanwhile, the effects on heat flow behaviors brought by boundary conditions are also considered to ensure that the proposed model can be easily adapted to different boundary conditions. The effectiveness and accuracy of the proposed model has been verified by both simulations and experiments.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • On Bayesian Optimization-Based Residual CNN for Estimation of Inter-Turn
           Short Circuit Fault in PMSM

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      Authors: Qiang Song;Mingsheng Wang;Wuxuan Lai;Sifang Zhao;
      Pages: 2456 - 2468
      Abstract: Interturn short circuit (ITSC) fault diagnosis at its early stage is very essential to improve the security of permanent magnet synchronous motors. In this article, a Bayesian optimization (BO) based residual convolutional neural network (CNN) algorithm for ITSC fault diagnosis was proposed. There are mainly two aspects of the contributions. First, it is a challenge to apply a conventional CNN on time-series signal tasks as they can only look back on history with a liner size, which will limit the network depth. Moreover, to obtain enough characteristics from acquired signals, the proposed algorithm requires adequate network depth, which may result in degradation difficulties. To solve these problems, a residual connection is embedded into the dilated CNN. Second, with the increase of network depth, the possible combination of hyperparameters will grow geometrically, thus the hyperparameters tuning will cost considerable time. To overcome this, the BO algorithm is adopted to select the optimal hyperparameter combination automatically. To demonstrate the effectiveness of the proposed algorithm, a motor fault experiment with various operating conditions was conducted on the motor that can be set for 17 fault severity levels. The test results and comparisons with other five algorithms show the advantage of the proposed algorithm.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Inertia and Grid Impedance Emulation of Power Grid for Stability Test of
           Grid-Forming Converter

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      Authors: Jiashi Wang;Ke Ma;
      Pages: 2469 - 2480
      Abstract: The virtual synchronous generator (VSG) control is a promising solution for the grid-forming converters to enhance the inertia of the converter-based power grid. The virtual inertia and output impedance of the VSG are the important behaviors to be focused. However, the virtual inertia of grid-forming converters may cause active power oscillation due to the interaction with the power inertia of grid through the low-frequency band grid impedance. Besides, the resonance can be also triggered by the interaction between middle-frequency impedance of power grid and output impedance of converter. In order to test the stability of grid-forming converter, accurate emulation of grid behaviors from more aspects, including inertia and impedance under wider frequency ranges, is becoming critical. This article proposes a grid emulation method to mimic the inertia and impedance characteristics of power grid, targeting for the stability test of grid-forming converter under multifrequency bands. A high-switching-frequency converter and a low-switching-frequency converter are adopted in the proposed emulator structure to achieve both high capability in respect to control bandwidth and power level. Moreover, the virtual impedance control is integrated with the VSG control to emulate the line impedance and inertia within relatively wider frequency ranges. The realization of virtual impedance is achieved without derivation terms nor low pass filter. Finally, the performance of the proposed emulator is verified by various simulations and experimental measurements.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • An Online DC-Link Capacitance Estimation Method for Motor Drive Systems
           Based on an Intermittent Reverse-Charging Control Strategy

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      Authors: Tianze Meng;Pinjia Zhang;
      Pages: 2481 - 2492
      Abstract: The dc-link capacitor in the three-phase ac–dc–ac motor drive system is a critical component. The degradation of dc-link electrolytic capacitors is a common failure that has a significant impact on system reliability, which can often lead to system breakdown or damage. It is significant to provide monitoring and prognostic techniques for dc-link capacitors to assist in preventive maintenance. To realize online estimation of the dc-link capacitance, a reverse-charging mode of dc-link capacitors is actively introduced during the normal operation, by actively altering the control of the power switches in the converter in an intermittent manner. During the proposed reverse-charging mode, the dc-link capacitor bank is charged by the motor, and the charging current exactly originates from the current in one particular phase, which can be designated and measurable in typical motor drive systems. Based on the reverse-charging mode, the capacitance can be calculated through the voltage rise and charging current. Simulation and experimental tests are implemented to verify the accuracy and feasibility of the proposed method. It is shown that this method is capable of providing online monitoring of dc-link capacitors with high accuracy.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Lithium-Ion Battery Cell Open Circuit Fault Diagnostics: Methods,
           Analysis, and Comparison

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      Authors: Shiyao Zhou;Ziqiang Chen;Tiantian Lin;
      Pages: 2493 - 2505
      Abstract: Battery fault diagnosis has great significance for guaranteeing the safety and reliability of lithium-ion battery (LIB) systems. Out of many possible failure modes of the series–parallel connected LIB pack, cell open circuit (COC) fault is a significant part of the causes that lead to the strong inconsistency in the pack and the reduction of pack life. Therefore, it is extremely important to diagnose COC faults in real time. Motivated by this fact, we propose Kirchhoff's law based method, short-time Fourier transform based method, the Pearson correlation coefficient based method, dual extended Kalman filter (DEKF) based method, and long short-term memory recurrent neural network based method for diagnosing COC fault. These diagnostic approaches do not rely on other sensor data except pack current and terminal voltages of modules composed of cells in parallel. Furthermore, several experiments on a 4S-3P battery pack are taken under time-varying ambient temperature conditions to evaluate and compare the computation cost, diagnostic delay, and accuracy of these approaches. Test results show that only the DEKF-based approach owns the weakest robustness, and Kirchhoff's law based method with the merit of the lowest diagnostic delay and computation cost is the most appropriate approach for online COC fault diagnosis.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Interturn Short-Circuit Fault Diagnosis of Interior Permanent Magnet
           Synchronous Motor for Electric Vehicle Based on Search Coil

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      Authors: Wan Huang;Bochao Du;Tiannan Li;Yousu Sun;Yuan Cheng;Shumei Cui;
      Pages: 2506 - 2515
      Abstract: This article proposes an interturn short-circuit fault diagnosis method for permanent magnet synchronous machines for electric vehicles based on search coils (SC) with a unique structure. In this proposed structure, the SCs are uniformly wound in the main flux direction of each phase, and the number of SCs is twice the number of phases, resulting in significant cost savings. Based on this structure, a novel fault feature based on the negative-sequence components of the second carrier frequency sideband harmonics in the voltage signal of the SC is proposed. As a result, this fault characteristic frequency component is not only more obvious than the fundamental component used in the traditional SCs method but also can be transformed to a dc indicator by two coordinate transformations, which is conducive to online implementation in both stationary and nonstationary conditions. Finally, experiments are presented to verify the proposed diagnosis strategy.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Investigation of Deformation Fluctuation of IGBT Chips Under Switching
           Conditions Using the Dynamic Field Reconstruction Method

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      Authors: Jiahao Wang;Libing Bai;Cong Chen;Jie Zhang;Quan Zhou;Lulu Tian;Jun Luo;Wei Huang;Yuhua Cheng;
      Pages: 2516 - 2528
      Abstract: Insulated gate bipolar transistor (IGBT) chips are crucial core components in power electronic modules. It is of great significance to investigate the deformation characteristics of IGBT chips induced by the electro-thermal-mechanical coupling. In this article, a field reconstruction technique based on scanning laser displacement measurement is developed to accurately capture the dynamic deformation field distribution on the surface of IGBT chips. Based on this method, a comprehensive investigation of the impacts of switching conditions on the deformation fluctuation characteristics of IGBT chips is implemented. The results indicate the middle region of the IGBT chip suffers from a relatively larger deformation compared to the edge area. In particular, the largest deformation fluctuation occurs near the heel of bonding wires. In addition, it is also observed that the deformation fluctuation is negatively correlated with the switching frequency, meanwhile positively related to load amplitude, and shows a trend of increasing first, and then, decreasing with duty cycle. This work provides an intuitive and effective method for the dynamic deformation field characterization of IGBT chips. Furthermore, the outcomes obtained in this article can also provide confident evidence and important data to facilitate more precise reliability analysis and evaluation for power electronic modules.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Floating-Reference On-State Voltage Measurement Strategy for Condition
           Monitoring Application

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      Authors: Moein Ghadrdan;Saeed Peyghami;Hossein Mokhtari;Frede Blaabjerg;
      Pages: 2529 - 2538
      Abstract: Due to its acceptable sensitivity to aging, on-state voltage is one of the best degradation indicators ever devised to monitor the condition of power semiconductors. The steep changes in the voltage of the semiconductors during switching have prompted the development of various circuits to extract the on-state voltage. This article proposes a simple converter-level structure for measuring the on-state voltage of every power semiconductor in a three-phase conventional inverter. As a result of its features, the proposed circuit enables the development of a hand-held portable monitoring device that can be used independently of the converter. Detailed information is given on how to design and select the components of the proposed monitoring system, along with its optimal operating conditions. In addition to the simulation results, a proof-of-concept prototype has been developed to evaluate the measurement accuracy and dynamic performance of the proposed circuit for the application of a three-phase inverter. The results confirm the overall effectiveness of the proposed topology and its comparable performance.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • A Real-Time Open-Circuit Fault Diagnosis Method Based on Hybrid Model Flux
           Observer for Voltage Source Inverter Fed Sensorless Vector Controlled
           Drives

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      Authors: Naizhe Diao;Yingwei Zhang;Xianrui Sun;Chonghui Song;Wenwen Wang;Haifeng Zhang;
      Pages: 2539 - 2551
      Abstract: This article presents a open-circuit fault diagnosis method for a sensorless vector control system based on the voltage–current hybrid model flux observer. The error voltage, which is obtained after a PI module, is used as a diagnostic factor. This PI module is designed to correct the deviation between the voltage model flux observer and the current model flux observer. The error voltage is not affected by load and speed variation. First, the activation function is used to separate fault information and normal information, and the feature function is defined to describe the signal feature in healthy and faulty conditions. Second, a second-order moving mean filtering method is proposed to reduce the storage of the error voltage data and increase the timeliness of diagnosis. Finally, the fault is diagnosed and located through logical calculations. Compared with conventional methods, this method features the timeliness of fault diagnosis in a closed-loop system and robustness with respect to speed and load changes. It reduces the storage and operation burden such that it can be easily implanted into the control algorithm as a subroutine. Simulations and experiments show the accuracy and superiority of the proposed fault diagnosis method for voltage source inverter fed sensorless vector controlled drives.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Condition Monitoring Method for Heatsink of Traction Inverter Using ANN
           and OWD

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      Authors: Yaoyi Yu;Xiong Du;Junjie Zhou;Hongyu Ren;
      Pages: 2552 - 2564
      Abstract: This article proposes a novel condition monitoring method for heatsink of traction inverter of urban rail train by detecting the change of temperature dynamic curves. Artificial neural network is used to predict the reference curves of healthy state under various working conditions, and the differences between temperature dynamic curves are extracted by one-way distance algorithm. This method is suitable for the condition monitoring of heatsink of urban rail train, because first it meets the diversity of operation conditions and nonthermal equilibrium state of traction inverter. Moreover, its implementation does not cause intrusion to the original system, and can realize online monitoring. Finally, the effectiveness is experimentally verified.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Synthetic Resilience Exploration and Economic Defense Strategy for
           Microgrid-Level AC/DC Hybrid Energy System

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      Authors: Chaoyu Dong;Junjun Wang;Xiangke Li;Chi Jin;Wentao Jiang;Zhe Zhang;Hongjie Jia;
      Pages: 2565 - 2576
      Abstract: For the ac/dc hybrid energy system, a resilience-oriented defense strategy is developed for survivability enhancement when subject to severe energy disruptions. On account of heterogeneous components, an integration index of synthetic resilience (SR) is formulated to assess the resilience capability of hybrid energy systems in the event of sudden energy changes. The derived SR is systematically illustrated in this work, which not only reveals its convexity feature but also visualizes the inherent self-healing resources during the ac/dc energy interaction. Based on the proposed resilience index and interlinking bridge of bidirectional converter, an economic defense strategy concerning uncertainties from renewable energies and loads is developed and system resilience is consequently reinforced by dispatching distributed energies according to individual marginal cost. Without the global coordination and mode transition, the system resilience is significantly strengthened and assessed by the proposed index and defense strategy, which formulates an operational paradigm for the microgrid-level energy hybridization considering load variation and renewable energy penetration. To completely demonstrate the effectiveness of the proposed index and defense strategy for the hybrid energy system, the controller-hardware-in-the-loop experiment results have been provided from six aspects of steady-state operation, dc demand variation, ac demand variation, renewable energy fluctuations, dc energy source failure, and ac energy source failure.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Selective Virtual Synthetic Vector Embedding for Full-Range Current
           Harmonic Suppression of the DC Collector

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      Authors: Feng An;Biao Zhao;Bin Cui;Yushuo Chen;Lu Qu;Zhanqing Yu;Rong Zeng;
      Pages: 2577 - 2588
      Abstract: With the rapid development of rene wable energy (e.g., wind and photovoltaic energy) and energy storage, the dc collector has become an effective conversion link of distributed energy access to medium-voltage power distribution grids. However, considering the inconsistency of dc voltage and the duty cycle of each submodule, the traditional carrier phase-shifting modulation is difficult to achieve the excellent harmonic characteristic in the dc collector, thereby introducing difficulties in the design of passive filters. To solve this problem, this article proposes a selective virtual synthetic vector embedding algorithm to realize full-range current harmonic suppression in the dc collector system. In this scheme, the switching voltage vectors outputted by each submodule are sorted, and the voltage vectors are selectively extracted and synthesized to calculate the embedded virtual voltage vector. Afterward, the voltage vector of each submodule is rotated and calculated online from the perspective of space geometry, and the optimal carrier phase combination in variable-angle carrier phase-shift modulation is obtained. Finally, the experimental results show that the proposed control algorithm can not only be used in the dc collector with any number of modules but also achieve fast and effective harmonic suppression in the whole operating range.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • A Wide Bandwidth GaN Switching Power Amplifier of Active Magnetic Bearing
           for a Flywheel Energy Storage System

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      Authors: Hong-Jin Hu;Kun Liu;Haoze Wang;Jing-Bo Wei;
      Pages: 2589 - 2605
      Abstract: A switching power amplifier (SPA) provides the driving current for an active magnetic bearing (AMB) to achieve magnetic suspension (MS) control. The performances of the current bandwidth and current ripple should be significantly considered in the SPA of the AMB. The SPA can obtain a wide bandwidth by increasing the dc-link voltage. However, a high dc-link voltage will cause a high current ripple. To achieve a wide bandwidth and low current ripple, a new GaN-device-based SPA for the AMB of a flywheel energy storage system (FESS) is proposed in this article. The GaN SPA can operate at a high switching frequency and high dc-link voltage. Thus, the GaN SPA can improve the performance of the current bandwidth and current ripple compared to the conventional SPA. According to the characteristics of the GaN SPA, a low-loss PWM method and an optimal dead time strategy is proposed to increase the efficiency of the SPA. Furthermore, a high-response control approach of dead-beat model predictive control is proposed to further improve the current bandwidth. The proposed GaN SPA is applied in a 500-kW MS FESS prototype. The effectiveness of the SPA is verified experimentally.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Multiport Control With Partial Power Processing in Solid-State Transformer
           for PV, Storage, and Fast-Charging Electric Vehicle Integration

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      Authors: Liran Zheng;Rajendra Prasad Kandula;Deepak Divan;
      Pages: 2606 - 2616
      Abstract: This article proposes a multiport control method to enable partial power processing (PPP) in a medium-voltage (MV) multiport solid-state transformer (SST). MV multiport SSTs are promising in integrating low-voltage dc sources or loads such as solar photovoltaic, energy storage, and electric vehicles into smart grids without bulky line-frequency transformers. Compared with voltage-source SST, current-source (CS) SST features single-stage isolated bidirectional ac/ac, ac/dc, or dc/dc conversion using an inductive dc link. For a multiport CS SST, it is revealed in this article that the PPP capability can be enabled through the proposed control without extra hardware, different from the case of voltage-source converters where special hardware architecture is required for the PPP. With the PPP, most power exchange between LV ports is processed by only a fraction of the entire conversion stage, leading to reduced dc-link current, volume, loss, and improved efficiency. The proposed multiport PPP control scheme is analyzed to verify the advantages across a wide voltage and power range against conventional full power processing (FPP) multiport control, using the soft-switching SST (S4T) with reduced conduction loss as an example. Comparative experimental results based on a SiC three-port S4T prototype verify the effectiveness of the proposed PPP scheme against the FPP scheme under both steady state and dynamic conditions. The dc-link current reduction is measured to be more than 36%. Significantly, the proposed multiport PPP control scheme is generic and applicable to any hard-switching or soft-switching CS SSTs without extra hardware.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • A Practical Current Source Inverter-Based High-Power Medium-Voltage PV
           System

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      Authors: Ling Xing;Qiang Wei;Yunwei Li;
      Pages: 2617 - 2625
      Abstract: The power converters currently used in high-power (a few megawatts) medium-voltage PV systems require the use of a line-frequency transformer (LFT), which is bulky and costly. To solve this issue, cascaded H-bridge converter and modular multilevel converter based converters were proposed and investigated in the literature. They can eliminate the LFT but suffer several technical challenges, one of which, for example, is a power imbalance. To address these challenges, extra efforts, such as modified converters, modulations, and controls, are needed. Such extras burden the original converters and introduce new challenges. Therefore, a new power converter is proposed in this work. It eliminates the LFT without these challenges faced by the existing solutions. In addition, it features reliable short-circuit protection, high scalability, simple, and well-proven converters. The operation principle is introduced, and the control scheme is developed. The performance is investigated and verified based on both simulations and lab-scaled experiments.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • New Converter Solution With a Compact Modular Multilevel Structure
           Suitable for High-Power Medium-Voltage Wind Turbines

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      Authors: Gustavo F. Gontijo;Tamas Kerekes;Dezso Sera;Mattia Ricco;Laszlo Mathe;Remus Teodorescu;
      Pages: 2626 - 2645
      Abstract: Modern wind turbines with increasing power levels are continuously emerging. These power levels are reaching a point where excessively high currents are obtained if the traditional low-voltage wind-turbine structure is adopted. High currents lead to excessively high losses and the need for bulky and heavy conductors to carry them. A medium-voltage structure should be a more competitive alternative to be adopted in high-power wind turbines. In this article, a new converter solution with a modular multilevel structure suitable for driving modern/future high-power medium-voltage wind turbines is proposed. This converter topology has desirable features common to modular multilevel converters, such as the improved reliability at high voltage levels, and the possibility to synthesize high-power-quality staircase-shape voltages, which leads to low requirements for harmonic and ${dv}/{dt}$ filters. Furthermore, the proposed converter presents reduced capacitance and inductance requirements compared with other well-established modular multilevel converter topologies, which should result in a lighter and more compact solution. The proposed solution could potentially allow for the reduction of the overall costs of the supporting structure required to withstand the weight of the wind turbine. Simulation and experimental results are presented in this article to validate the proposed topology.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Controller-Saturation-Based Transient Stability Enhancement for
           Grid-Forming Inverters

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      Authors: Cheng Luo;Xikui Ma;Teng Liu;Xiongfei Wang;
      Pages: 2646 - 2657
      Abstract: This article reveals that the saturation block (SB) used with the power-angle control loop can enhance the transient stability of grid-forming (GFM) inverters. Three methods of using the SB in the power-angle loop are examined based on power-angle curves. It is found that all can enhance the transient stability of GFM inverters by either decreasing the acceleration area or increasing the deceleration area. At the same time, the threshold value selection of SB in the three schemes is also explained, considering the tradeoff between the transient stability and the response speed. A holistic comparison of the three schemes recommends the scheme with the SB used for power error adopted by the GFM inverters. Finally, experimental tests confirm the effectiveness and correctness of the analysis.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • A Novel Low Device Count Four-Port Converter Based Solar-Fed Off-Grid
           System for Catering Household Hybrid AC/DC Loads

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      Authors: Amal C Sunny;Dipankar Debnath;
      Pages: 2658 - 2667
      Abstract: Hybrid ac/dc off-grid topologies offer the combined advantage of higher energy efficient dc loads, and existing low-cost ac loads. Such budding topologies tender a promising solution for rural electrification when supplied from solar power along with battery backup. The desirable features of such a scheme for catering household appliances are: low semiconductor count, continuous current ports for PV, battery and dc load, low-voltage levels for PV and battery, dc and ac load voltage regulation, maximum power point tracking, battery overcharge and deep-discharge protection, high-voltage boosting sans low-frequency transformer, and reduced power converter stages. The schemes reported in the literature lack one or more of these features. To address this concern, a hybrid ac/dc scheme is proffered. The first stage is formed by a novel three-switch four-port converter, which facilitates most of the aforesaid features required in a hybrid system. The remaining features are obtained using a conventional dc–ac converter, which forms the second stage of the proposed solution. The overall solution is substantiated through comprehensive analysis and experimental demonstrations using a 400 W experimental prototype.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Backstepping-Based Direct Power Control for Dual-Cage Rotor Brushless
           Doubly Fed Induction Generator

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      Authors: Xiaoming Yan;Ming Cheng;
      Pages: 2668 - 2680
      Abstract: In this article, we propose a backstepping (BS)-based direct power control (DPC) strategy for the dual-cage rotor brushless doubly fed induction generator (DCR-BDFIG). The relationship between the power winding (PW) output power and the control winding (CW) voltage is derived according to the complete mathematical model of DCR-BDFIG. Based on that, a BS-based DPC controller, also known as a nonlinear controller, is designed with the global asymptotic stability analyzed for the grid-connected DCR-BDFIG. Compared with the dual-closed-loop control in the advanced vector control method, only single-closed-loop is required for the PW power in the proposed BS-based control scheme, and thus it has more simple structure and faster responses. The global stability of the proposed control scheme can be easily guaranteed with a Lyapunov function properly selected. In addition, in order to improve the performance of the proposed BS-based DPC strategy under unbalanced network, the resonant controller is introduced to suppress the oscillating components in the PW power, PW current, and CW current, whose harmonic order is twice of the grid frequency referring to the synchronous reference frame. Finally, the detailed experimental results demonstrate the effectiveness of the proposed control strategy.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Adaptive Model-Predictive-Control-Based Real-Time Energy Management of
           Fuel Cell Hybrid Electric Vehicles

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      Authors: Chao Jia;Wei Qiao;Junwei Cui;Liyan Qu;
      Pages: 2681 - 2694
      Abstract: To compete with battery electric vehicles, fuel cell (FC) hybrid electric vehicles (FCHEVs) are required to offer better performance in fuel economy and FC durability. To this end, this article proposes a novel real-time adaptive model predictive control (AMPC)-based energy management strategy (EMS) for FCHEVs to improve their fuel efficiency and mitigate the degradation of their onboard FC hybrid systems. First, a linear parameter-varying (LPV) prediction model of the FC hybrid system that considers the system parameter variation is developed. The model offers sufficient accuracy while enabling the real-time implementation capability of the AMPC. Then, an AMPC strategy is proposed to optimally distribute the load current of the FCHEV between the FC and the battery in real time. In each control interval of the AMPC, the LPV prediction model is updated online to adapt to the variations of the battery state of charge. The constrained optimization problem of the AMPC is then formulated to achieve a desired tradeoff among four performance metrics and is further transformed into a quadratic programming problem, which can be solved in real time. Hardware-in-the-loop tests are performed on a downscaled FC hybrid system with the proposed AMPC-based EMS, a commonly used rule-based EMS, an equivalent consumption minimization strategy, and an improved MPC-based EMS, respectively. Results show that among the four real-time EMSs, the AMPC-based EMS achieves the best performance in reducing hydrogen consumption and FC current fluctuation and the smallest optimality gap with respect to an offline dynamic programming-based optimal EMS.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Effect of the Sampling Parameters in FOCV-MPPT Circuits for Fast-Varying
           EH Sources

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      Authors: Matias Carandell;Andrew S. Holmes;Daniel Mihai Toma;Joaquín del Río;Manel Gasulla;
      Pages: 2695 - 2708
      Abstract: The fractional open-circuit voltage (FOCV) method is extensively used in low-power energy harvesting (EH) sources to extract maximum power. For fast-varying EH sources, a fast sampling rate is required. This work theoretically analyzes the influence of the sampling time and period on the harvested power of sinusoidal EH sources. In addition, the circuit limitations to achieve a fast sampling rate are presented and circuits to deal with them proposed and implemented. Furthermore, one of the circuits is based on a novel pseudoFOCV method and achieves the fastest sampling rate. Experimental tests are performed with a 2 Hz, 1 to 3 V sinusoidal source having an output resistance of 127 Ω, and the results are shown to agree with theoretical predictions. It is shown that the harvested power increases with the sampling rate when the sampling time is negligible (sampling 15 times faster than the source frequency extracts around 99% of the maximum), and for fixed sampling times, there is an optimum sampling rate where the harvested power is maximum. The first result is generic and valid for methods other than the FOCV. Tests were also performed with a small-scale wave energy converter placed in a linear shaker emulating a sea environment. Harvested power increases by 25% with respect using a commercial FOCV unit with a low sampling rate.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Uniform and Simplified Small-Signal Model for Inductive Power Transfer
           Systems

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      Authors: Guangce Zheng;Chaoqun Qi;Yu Liu;Junrui Liang;Haoyu Wang;Minfan Fu;
      Pages: 2709 - 2719
      Abstract: This article explores the unification and simplification of the small-signal model for representative inductive power transfer systems. Various famous compensations are included, such as the S–S, LCC–S, and LCC–LCC. Through system decomposition, the uniform model concept is applied to the inverter, rectifier, and resonant tank. Meanwhile, the model complexity and similarity are discussed for various resonant tanks, and proper simplification is used to reduce the model order. The uniform equivalent circuit model is finally proposed for the target systems, based on which the explicit transfer function can be represented by a general polynomial equation. The model order of the S–S, LCC–S, and LCC–LCC systems are five, two, and five, respectively. The experiment shows the model is accurate up to one-fifth of the switching frequency for all the target systems.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Reconfigurable Rectifier-Based Detuned Series-Series Compensated IPT
           System for Anti-Misalignment and Efficiency Improvement

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      Authors: Yang Chen;Shuangjiang He;Bin Yang;Shuxin Chen;Zhengyou He;Ruikun Mai;
      Pages: 2720 - 2729
      Abstract: For an inductive power transfer (IPT) system, mobility is one of the most attractive features, but coupling variations can dramatically affect the system's output. In this article, a reconfigurable rectifier-based detuned series-series (SS) compensated IPT system is proposed to tolerate an extensive coupling range and improve the system efficiency simultaneously. The reconfigurable rectifier, which can operate in a full-bridge rectifier mode or a half-bridge rectifier mode, is used to alter the equivalent ac load from one value to the other so the expected coupling range of the detuned SS topology can be extended. At the same time, the system efficiency is also partly improved because the ac load is changed to get closer to the optimal load of the IPT system. First, a detuned SS IPT system with the reconfigurable rectifier is presented and followed by the analysis of the working modes. Then, a detailed parameter design process and switching control of the reconfigurable rectifier are introduced. Finally, a 400-W prototype was constructed to verify the validity of the proposed method. The experimental results demonstrate that the output power fluctuation of the proposed IPT system is less than 17.5% and the lowest efficiency can be improved from 68.6% to 87.5% with the coupling coefficient varying from 0.1 to 0.4. The proposed method can implement significant antimisalignment and efficiency improvement simultaneously, and it is regarded as a potential solution for low-power IPT applications with high spatial mobility.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • A Vertically Modularized Reconfigurable Wireless Power Transfer System:
           Architecture, Modeling, and Design

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      Authors: Huan Zhang;Yaoxia Shao;Ning Kang;Haojun Qin;Chengbin Ma;Ming Liu;
      Pages: 2730 - 2742
      Abstract: It is known that megahertz (MHz) wireless power transfer (WPT) is particularly beneficial in terms of spatial freedom of power transfer and circuit compactness. Meanwhile, design complexity is a main obstacle to the spread of MHz WPT. In this article, a new modular design concept is proposed to conveniently reconfigure a MHz WPT system for different applications. Multiple predesigned functional unit modules can easily be combined to form a complete new WPT system with a different power level and transfer distance. A vertically stacked architecture is especially chosen to save space in actual applications. Detail analytical derivations are conducted to analyze the modular design, including the influence of different combinations of the unit modules. A new interleaved coil design is developed to reduce the proximity effect and cross coupling among the vertically stacked modules. Finally, the modular design concept is validated by experiments and demonstrates the desired scalability in both power levels and transfer distances. Through 15 combinations of the unit modules, the experimental WPT system can be reconfigured to provide an output power from 4 to 116 W. The effective transfer distance can be also extended from 30 to 90 mm and 80% system dc–dc efficiency is achieved within a 70-mm transfer distance using 100-mm-diameter printed circuit board coils.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • A 1-W, 6.78-MHz Wireless Power Transfer System With Up-to-16.1% Light-Load
           Efficiency Improvement and Instant Response Through Single-Cycle-Based
           D TX Control

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      Authors: Yutang Chen;Yuxuan Luo;Jianping Guo;
      Pages: 2743 - 2753
      Abstract: This article presents a 6.78-MHz wireless power transfer system with transmission power control. The proposed receiver (RX) with a simplified 0X/1X structure can achieve single-stage regulation in series–series resonant tank, where the charge and discharge cycle are only dependent on the hysteresis comparator. Asymmetric pulsewidth modulation is adopted in the proposed transmitter (TX), where the duty ratio (${D}_{text{TX}}$) is switched based on the charge or discharge cycle of RX. With the proposed single-cycle-based ${D}_{text{TX}}$ control, the ${D}_{text{TX}}$ will be switched to 0.25 in the discharge cycle, while it is 0.5 in the charge cycle for maximum power transmission. Therefore, the end-to-end (E2E) efficiency especially at light-load conditions can be improved, and the recovery time is nearly instant when loading changes suddenly, i.e., neglectable voltage droop can be achieved. The RX is implemented by a printed circuit board and the TX is fabricated in a 0.18-μm CMOS technology. In the measurement, an output power range from 10 to 1000 mW is achieved with 60.6% peak E2E efficiency. The significant E2E efficiency improvement is observed over 10–255 mW and the maximum improvement is 16.1%. The measured load transient response verifies that the proposed design has instant response and neglectable voltage droop.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Power-Spilt-Based Wireless Charging System With Communication-Free
           Coordination Control

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      Authors: Xiaoqiang Wang;Liangxi He;Jianping Xu;Chi-Kwan Lee;Chi K. Tse;
      Pages: 2754 - 2767
      Abstract: In this article, a power-split-based wireless charging system (WCS) with communication-free coordination control is proposed to combat wide load and coupling variations. By using a magnetic integrated inductor, two power delivery channels are created from a single receiver coil. Large portion of received energy is directly delivered to the load. Small amount of energy is converted by using a low-voltage low-power dc–dc converter to regulate the output voltage or current achieving constant voltage (CV) or constant current (CC) charging operation. This proposal achieves higher power conversion efficiency than the traditional two-stage cascaded converter WCS. Since the dc–dc converter only processes partial power of the WCS system, this proposal reduces the voltage stress of the devices and design difficulty. A communication-free coordination control is applied, which is established by sensing the input current drop caused by the burst operation of the partial-power dc–dc converter. Thus, the CC-CV charging is realized by PWM control at the receiver (Rx) side, and the inverter is regulated with subharmonics control scheme to maintain nearly constant Rx coil current. Simulation results for both high-voltage high-power scenarios and low-voltage low-power (LVLP) scenarios are provided to investigate the operation of the proposed WCS. Finally, experimental results are captured from a 250 W/60–84 V LVLP prototype to validate the feasibility and practicability of proposed concept.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Design and Assessment of an Interoperable Wireless Power Transfer System
           Using an Impedance-Based Method

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      Authors: Denis Kraus;Grant A. Covic;Hans-Georg Herzog;Patrick A. J. Lawton;Feiyang Jackman Lin;
      Pages: 2768 - 2781
      Abstract: With the recently published standard, wireless charging systems for electric vehicles (EVs) are at the stage of preparing for mass market production. In order to have success, safe, and efficient wireless power transfer (WPT) public charging needs to be ensured and therefore interoperability is a key element in the design of such systems. In this article, a design methodology based on impedance planes is presented, which enables consideration of many interoperability aspects at an early stage in the design and has a high degree of flexibility. Four impedance interfaces are presented and operational boundaries and system requirements are added at each interface to establish capability ranges, which can be transferred to any other interface and used to define and assess the design space. Furthermore, this article shows how magnetic field leakage limitations can be considered in the design process. Experimental verification of the simulations is then undertaken and an example presented of how the primary electronics for a public charging use case scenario could be assessed or designed.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
  • Stable Wireless Power Transmission for a Capsule Robot With Randomly
           Changing Attitude

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      Authors: Jinyang Gao;Jinshan Zhou;Changshun Yuan;Zenglei Zhang;Chen Gao;Guozheng Yan;Ruiqin Li;Li Zhang;
      Pages: 2782 - 2796
      Abstract: Wireless power transmission (WPT) for a capsule robot (CR) has always been a challenging issue because the unpredictable CR attitude can destabilize the induced power of the receiving coil onboard the CR. This article proposes a new WPT system for stably powering the CR, and it mainly consists of a rotatable two-dimensional transmitting coil (R2DTC), a one-dimensional receiving coil (1DRC), and an attitude detection module (ADM). The R2DTC can excite a uniform and directional alternating magnetic field (AMF) covering the CR workspace, and the AMF amplitude and direction are controllable in the 3-D space. The 1DRC has a shape of thin-walled ring, for ease of being used as a CR outer shell. The ADM is fixed together with the 1DRC; it can detect the 1DRC attitude in real time and is implemented in a compact size. Referring to the 1DRC attitude, the R2DTC can regulate the AMF to stabilize the 1DRC induced power. This article presents design and implementation details of the WPT system, as well as experiments for its performance evaluation. The R2DTC is verified to supply stable power of 500 mW to the attitude-changing 1DRC at most cases, with a transfer efficiency ranging from 8.15% to 13.53%.
      PubDate: Feb. 2023
      Issue No: Vol. 38, No. 2 (2023)
       
 
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