for Journals by Title or ISSN
for Articles by Keywords

 A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z  

        1 2 | Last

  Subjects -> ELECTRONICS (Total: 138 journals)
Advances in Biosensors and Bioelectronics     Open Access   (Followers: 1)
Advances in Magnetic and Optical Resonance     Full-text available via subscription   (Followers: 4)
Advances in Microelectronic Engineering     Open Access   (Followers: 1)
Advances in Power Electronics     Open Access   (Followers: 7)
Aerospace and Electronic Systems, IEEE Transactions on     Hybrid Journal   (Followers: 50)
American Journal of Electrical and Electronic Engineering     Open Access   (Followers: 7)
Annals of Telecommunications     Hybrid Journal   (Followers: 4)
APL : Organic Electronics and Photonics     Hybrid Journal   (Followers: 1)
APSIPA Transactions on Signal and Information Processing     Open Access   (Followers: 2)
Archives of Electrical Engineering     Open Access   (Followers: 8)
Autonomous Mental Development, IEEE Transactions on     Hybrid Journal   (Followers: 5)
Bell Labs Technical Journal     Hybrid Journal   (Followers: 8)
Biomedical Engineering, IEEE Reviews in     Full-text available via subscription   (Followers: 14)
Biomedical Engineering, IEEE Transactions on     Hybrid Journal   (Followers: 11)
Biomedical Instrumentation & Technology     Full-text available via subscription   (Followers: 4)
Broadcasting, IEEE Transactions on     Hybrid Journal   (Followers: 5)
BULLETIN of National Technical University of Ukraine. Series RADIOTECHNIQUE. RADIOAPPARATUS BUILDING     Open Access   (Followers: 1)
Bulletin of the Polish Academy of Sciences : Technical Sciences     Open Access  
Canadian Journal of Remote Sensing     Full-text available via subscription   (Followers: 12)
China Communications     Full-text available via subscription   (Followers: 1)
Circuits and Systems     Open Access   (Followers: 7)
Consumer Electronics Times     Open Access   (Followers: 3)
Control Systems     Hybrid Journal   (Followers: 18)
Electronic Markets     Hybrid Journal   (Followers: 5)
Electronic Materials Letters     Hybrid Journal   (Followers: 2)
Electronics     Open Access   (Followers: 3)
Electronics and Communications in Japan     Hybrid Journal   (Followers: 4)
Electronics Letters     Hybrid Journal   (Followers: 15)
Embedded Systems Letters, IEEE     Hybrid Journal   (Followers: 14)
EURASIP Journal on Embedded Systems     Open Access   (Followers: 8)
Foundations and TrendsĀ® in Communications and Information Theory     Full-text available via subscription   (Followers: 5)
Foundations and TrendsĀ® in Signal Processing     Full-text available via subscription   (Followers: 4)
Frequenz     Full-text available via subscription   (Followers: 1)
Frontiers of Optoelectronics     Hybrid Journal   (Followers: 1)
Geoscience and Remote Sensing, IEEE Transactions on     Hybrid Journal   (Followers: 19)
Haptics, IEEE Transactions on     Hybrid Journal   (Followers: 4)
IEEE Consumer Electronics Magazine     Full-text available via subscription   (Followers: 7)
IEEE Journal of Emerging and Selected Topics in Power Electronics     Hybrid Journal   (Followers: 3)
IEEE Journal of the Electron Devices Society     Open Access   (Followers: 1)
IEEE Power Electronics Magazine     Full-text available via subscription  
IEEE Transactions on Audio, Speech, and Language Processing     Hybrid Journal   (Followers: 9)
IEEE Transactions on Automatic Control     Hybrid Journal   (Followers: 19)
IEEE Transactions on Consumer Electronics     Hybrid Journal   (Followers: 10)
IEEE Transactions on Electron Devices     Hybrid Journal   (Followers: 6)
IEEE Transactions on Information Theory     Hybrid Journal   (Followers: 13)
IEEE Transactions on Power Electronics     Hybrid Journal   (Followers: 11)
IEICE - Transactions on Electronics     Full-text available via subscription   (Followers: 7)
IEICE - Transactions on Information and Systems     Full-text available via subscription   (Followers: 7)
IET Power Electronics     Hybrid Journal   (Followers: 7)
IET Wireless Sensor Systems     Hybrid Journal   (Followers: 5)
IETE Journal of Education     Open Access   (Followers: 2)
IETE Journal of Research     Open Access   (Followers: 4)
IETE Technical Review     Open Access   (Followers: 1)
Industrial Electronics, IEEE Transactions on     Hybrid Journal   (Followers: 9)
Industry Applications, IEEE Transactions on     Hybrid Journal   (Followers: 5)
Informatik-Spektrum     Hybrid Journal  
Instabilities in Silicon Devices     Full-text available via subscription  
Intelligent Transportation Systems Magazine, IEEE     Full-text available via subscription   (Followers: 1)
International Journal of Advanced Electronics and Communication Systems     Open Access   (Followers: 3)
International Journal of Advanced Research in Computer Science and Electronics Engineering     Open Access   (Followers: 18)
International Journal of Advances in Telecommunications, Electrotechnics, Signals and Systems     Open Access   (Followers: 1)
International Journal of Aerospace Innovations     Full-text available via subscription   (Followers: 10)
International Journal of Applied Electronics in Physics & Robotics     Open Access  
International Journal of Biomedical Nanoscience and Nanotechnology     Hybrid Journal   (Followers: 4)
International Journal of Computational Vision and Robotics     Hybrid Journal   (Followers: 4)
International Journal of Computer & Electronics Research     Full-text available via subscription   (Followers: 2)
International Journal of Control     Hybrid Journal   (Followers: 9)
International Journal of Electronics     Hybrid Journal   (Followers: 2)
International Journal of Electronics & Data Communication     Open Access   (Followers: 3)
International Journal of Electronics and Telecommunications     Open Access   (Followers: 3)
International Journal of Granular Computing, Rough Sets and Intelligent Systems     Hybrid Journal   (Followers: 1)
International Journal of High Speed Electronics and Systems     Hybrid Journal  
International Journal of Microwave and Wireless Technologies     Hybrid Journal   (Followers: 1)
International Journal of Nano Devices, Sensors and Systems     Open Access   (Followers: 1)
International Journal of Nanoscience     Hybrid Journal   (Followers: 1)
International Journal of Numerical Modelling:Electronic Networks, Devices and Fields     Hybrid Journal   (Followers: 2)
International Journal of Power Electronics     Hybrid Journal   (Followers: 3)
International Journal of Power Management Electronics     Open Access  
International Journal of Review in Electronics & Communication Engineering     Open Access   (Followers: 1)
International Journal of Sensors, Wireless Communications and Control     Hybrid Journal   (Followers: 2)
International Journal of Systems, Control and Communications     Hybrid Journal   (Followers: 2)
International Journal on Communication     Full-text available via subscription   (Followers: 7)
International Journal on Electrical and Power Engineering     Full-text available via subscription   (Followers: 11)
ISRN Electronics     Open Access   (Followers: 1)
ISRN Signal Processing     Open Access  
Journal of Advanced Dielectrics     Open Access   (Followers: 1)
Journal of Artificial Intelligence     Open Access   (Followers: 5)
Journal of Circuits, Systems, and Computers     Hybrid Journal   (Followers: 1)
Journal of Electrical and Electronics Engineering Research     Open Access   (Followers: 1)
Journal of Electrical Bioimpedance     Full-text available via subscription   (Followers: 2)
Journal of Electrical Engineering & Electronic Technology     Full-text available via subscription   (Followers: 1)
Journal of Electromagnetic Analysis and Applications     Open Access   (Followers: 2)
Journal of Electromagnetic Waves and Applications     Hybrid Journal   (Followers: 1)
Journal of Electronic Design Technology     Full-text available via subscription   (Followers: 1)
Journal of Electronics (China)     Hybrid Journal   (Followers: 2)
Journal of Field Robotics     Hybrid Journal   (Followers: 3)
Journal of Guidance, Control, and Dynamics     Full-text available via subscription   (Followers: 49)
Journal of Intelligent Procedures in Electrical Technology     Open Access  
Journal of Low Power Electronics     Full-text available via subscription   (Followers: 4)
Journal of Low Power Electronics and Applications     Open Access   (Followers: 1)

        1 2 | Last

IEEE Transactions on Power Electronics
   [13 followers]  Follow    
   Hybrid Journal Hybrid journal (It can contain Open Access articles)
     ISSN (Print) 0885-8993
     Published by Institute of Electrical and Electronics Engineers (IEEE) Homepage  [172 journals]   [SJR: 3.308]   [H-I: 111]
  • IEEE Power Electronics Society Information
    • Pages: C3 - C3
      Abstract: Provides a listing of current committee members and society officers.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Table of contents
    • Pages: C1 - C4
      Abstract: Presents the cover/table of contents for this issue of the periodical.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • IEEE Transactions on Power Electronics publication information
    • Pages: C2 - C2
      Abstract: Provides a listing of current staff, committee members and society officers.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Input-Series-Output-Parallel Phase-Shift Full-Bridge Derived DC–DC
           Converters With Auxiliary LC Networks to Achieve Wide Zero-Voltage
           Switching Range
    • Authors: Guo; Z.;Sha, D.;Liao, X.;Luo, J.;
      Pages: 5081 - 5086
      Abstract: This letter proposes an input-series-output-parallel derived dc–dc converter composed of two phase-shift full-bridge (PSFB) dc–dc converters and two auxiliary LC networks. Each LC network is connected between the leading-leg midpoint of a module and the lagging-leg midpoint of the other one. For conventional PSFB converters, the lagging-leg switches may lose zero-voltage switching (ZVS) conditions at light loads. In the proposed converter, ZVS for lagging-leg switches can be achieved with the aid of the LC networks even at light loads. The efficiency of the converter at the light load is improved. Therefore, the proposed converter is suitable for the wide load range. The feature of the converter is analyzed. The performance of the proposed converter is verified by a 900 W experimental prototype.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Strategies to Accelerate Harmonic Minimization in Multilevel Inverters
           Using a Parallel Genetic Algorithm on Graphical Processing Unit
    • Authors: Roberge; V.;Tarbouchi, M.;Okou, F.;
      Pages: 5087 - 5090
      Abstract: Multilevel inverters form a popular class of high-power inverters due to their high-voltage operation, high efficiency, low switching losses, and low electromagnetic interference. Metaheuristics, such as the genetic algorithm (GA), have been used with success to compute optimal switching angles for multilevel inverters with many dc sources while minimizing several harmonics. However, these methods are computationally demanding and cannot easily be used for real-time control. In this letter, a parallel implementation of the GA on graphical processing unit (GPU) is proposed in order to accelerate the computation of the optimal switching angles for multilevel inverters with varying dc sources. Four approaches to parallelize and speed up the computation of the total harmonic distortion are presented and compared. By exploiting the massively parallel architecture of GPUs, the computation of optimal angles is accelerated by a factor of 469× compared to a sequential execution on CPU. The proposed solution optimizes multilevel inverters with 100 variable dc sources while minimizing the first 100 harmonics in 164 ms.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • An All-SiC High-Frequency Boost DC–DC Converter Operating at 320
           °C Junction Temperature
    • Authors: Zhong; X.;Wu, X.;Zhou, W.;Sheng, K.;
      Pages: 5091 - 5096
      Abstract: This letter presents the design, prototype development, operation, and testing of an 800 kHz, 1 kW, 800 V output boost dc–dc converter module that integrates SiC MOSFET and SiC Schottky diode die. It is observed that when the device loss is dominated by switching loss, the steady-state junction temperature of SiC MOSFET can reach as high as 320 °C. This is the highest self-heated junction temperature operation of SiC power devices under room temperature ambient reported in the literature. The high-frequency switching characteristics and high-temperature thermal reliability of the assessed converter are evaluated in detail. A solder-molten phenomenon during high junction temperature operation is detected and the die-attachment material is thus improved to enhance the high-temperature thermal reliability of the converter module. This study shows that the high-frequency capability of a gate driver and high-temperature die-attachment technology can be limiting factors preventing SiC power devices from operating at higher junction temperatures.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Improved Operation of SiC–BJT-Based Series Resonant Inverter With
           Optimized Base Drive
    • Authors: Sarnago; H.;Lucia, O.;Mediano, A.;Burdio, J.M.;
      Pages: 5097 - 5101
      Abstract: New semiconductor technology is enabling the design of more reliable and high performance power converters. In particular, silicon carbide (SiC) technology provides faster switching times, higher operating temperature, and higher blocking voltage. Among the new SiC devices, bipolar junction transistors (BJTs) present interesting features in terms of conduction and switching losses. However, one of the main drawbacks is that these devices have low gain, requiring high base current to activate them. As a consequence, the base drive circuit becomes more complex and the final efficiency is decreased. This letter presents an optimized base drive circuit for a zero-voltage switching series resonant inverter. The proposed circuit maximizes the driver efficiency and minimizes the driver current requirements. Moreover, the proposed circuit optimizes the power converter switching conditions, increasing the converter efficiency. The proposed base drive circuit has been tested with a SiC–BJT-based series resonant inverter applied to induction heating.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Novel Time Division Multiple Control Method for Multiple Output Battery
    • Authors: Tran; V.;Choi, W.;
      Pages: 5102 - 5105
      Abstract: Multiple output converters (MOCs) are widely used in electronic equipment for industrial, commercial, and military application such as the voltage regulator modules in portable electronic devices, multiple output power supplies, and multiple output charger due to their advantages in cost, volume, and efficiency. However, most of the MOCs developed so far have limitations in terms of the number of outputs, the tight regulation of all the outputs, the simplicity of the structure, and the ease of control. In this letter, a novel time division multiple control (TDMC) method which can regulate all of the outputs with high precision is proposed. The proposed method is simple in its control and structure. In addition, it provides an even degree of tight regulation for all the outputs. The validity and the feasibility of the proposed method are verified by applying it to a multiple output battery charger based on the double ended forward converter.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Synchronized Zero-Crossing-Based Self-Tuning Capacitor Time-Constant
           Estimator for Low-Power Digitally Controlled DC–DC Converters
    • Authors: Radic; A.;Straka, A.;Prodic, A.;
      Pages: 5106 - 5110
      Abstract: A hardware efficient method and system for estimating the time constant and measuring the current of the output capacitors in digitally controlled switch-mode power supplies is introduced. The estimator emulates the equivalent RC circuit of the output capacitor with a much smaller version, placed in parallel, and adjusts its own resistance until the two circuits have the same time constant. The adjustment is based on a novel zero voltage crossing detection method and on synchronization with the digital pulse-width modulator operation. The effectiveness of the new estimator is verified with a 5 V to 1 V/5 A, 500-kHz buck converter prototype utilizing an optimal response controller. The experimental results show accuracy within a few tens of nanoseconds in the detection of capacitor zero-current crossing points, corresponding to a smaller than a 1.5% error in the time constant estimation, and, compared to an imperfectly tuned system, about 40% smaller voltage deviation during transients.
      PubDate: Oct. 1 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Improving High-Frequency Performance of an Input Common Mode EMI Filter
           Using an Impedance-Mismatching Filter
    • Authors: Luo; F.;Dong, D.;Boroyevich, D.;Mattavelli, P.;Wang, S.;
      Pages: 5111 - 5115
      Abstract: This letter investigates into the impedance interaction between the electromagnetic interference (EMI) filter and the noise propagation path, and its influences on the filter design. It proves that the impedance resonance in the propagation path decreases the filter's high-frequency in-circuit attenuation. This letter proposes a method to improve the filter's high-frequency performance using an impedance-mismatching filter. The impedance-mismatching filter damps the resonance in the common mode (CM) noise propagation path and eliminates the high-frequency noise spike. By applying this method in the filter design, the CM inductor of the EMI filter can be significantly reduced since the EMI filter avoids the overdesign caused by its high-frequency performance degradation, and the filter can potentially achieve high power density. This letter also proposed a design procedure for this impedance-mismatching filter. An improved EMI filter design method considering this impedance mismatching is also proposed in this letter.
      PubDate: Oct. 1 2014
      Issue No: Vol. 29, No. 10 (2014)
  • A Modified Dual-Output Interleaved PFC Converter Using Single Negative
           Rail Current Sense for Server Power Systems
    • Authors: Dusmez; S.;Choudhury, S.;Bhardwaj, M.;Akin, B.;
      Pages: 5116 - 5123
      Abstract: The interleaved PFC topologies have been widely used since they allow for smaller components, improved thermal performance, better transients, and reduced current ripple. In this letter, conventional two-phase interleaved universal input PFC topology is modified to obtain dual independent outputs for server applications, which minimizes the transient effects of interleaving legs on each other through two split dc buses. A new digital control method using only one current sensor located on the negative dc rail is proposed to control the dual-output interleaved PFC converter. Double-loop digital control of two interleaving stages is implemented using a single low-cost microcontroller (TMS320F28027-PiccoloA). In the proposed control technique, the control circuitry, input voltage, and current sensing circuits are shared between two PFC power stages, which minimize the size and the cost of the design significantly.
      PubDate: Oct. 1 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Theoretical Considerations for Single-Phase Interleaved Converters
           Operated With SHE-PWM
    • Authors: Konstantinou; G.;Agelidis, V.G.;Pou, J.;
      Pages: 5124 - 5128
      Abstract: This letter defines selective harmonic elimination pulse width modulation (SHE-PWM) formulations for single-phase, interleaved converters. Through precalculated solutions, interleaved converters work at the same operating point while eliminating multiple low-order harmonics. It is shown that multiple continuous solutions can be acquired for three-level interleaved waveforms. Extending the method to multiple levels further complicates the problem and reduces both the number and continuity of the solutions. Searching for solutions when the maximum possible number of harmonics, that can be minimized using this PWM method, is reduced confirms that such compromise can provide additional solutions with a minimal effect on the waveform’s harmonic distortion. The SHE-PWM considerations are verified with simulations and experimental results.
      PubDate: Oct. 1 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Self-Powered Gate Driver for Normally-ON SiC JFETs: Design Considerations
           and System Limitations
    • Authors: Peftitsis; D.;Rabkowski, J.;Nee, H.;
      Pages: 5129 - 5135
      Abstract: A circuit solution to the normally-ON property of the normally-ON silicon carbide junction field-effect transistor, namely the self-powered gate driver, has been recently proposed. This letter sheds some light on the design process of the self-powered gate driver concept as well as limitations from the system perspective. It is experimentally shown that the parameters of the self-powered gate driver must be chosen taking into account a tradeoff between a fast response and stable operation of the driver. Moreover, the influence of the shoot-through current in the fast activation of the self-powered gate driver is also presented.
      PubDate: Oct. 1 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Analysis, Design, and Experimental Results of the Semidual-Active-Bridge
    • Authors: Kulasekaran; S.;Ayyanar, R.;
      Pages: 5136 - 5147
      Abstract: A new soft-switching circuit topology derived from the popular dual-active-bridge converter (DAB) topology is proposed for applications requiring only unidirectional power flow such as the dc–dc stage of a photovoltaic power converter, and battery charger for electric vehicles. The topology named as the semidual active bridge (S-DAB) is obtained by replacing the fully active (four switches) bridge on the load side of a DAB by a semiactive (two switches and two diodes) bridge. In addition to the reduced number of active switches, the topology offers several other advantages including extended zero-voltage switching (ZVS), and smaller output filter requirement. The operating principles, waveforms in different intervals and expression for power transfer, which differ significantly from the basic DAB topology, are presented in detail. The ZVS characteristics and requirements are analyzed in detail and compared to those of DAB. A small-signal model of the new configuration is also derived. The analysis and performance of S-DAB are validated through extensive simulation and experimental results from a 1-kW hardware prototype.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Evaluation of 6.5-kV SiC p-i-n Diodes in a Medium-Voltage, High-Power
           3L-NPC Converter
    • Authors: Filsecker; F.;Alvarez, R.;Bernet, S.;
      Pages: 5148 - 5156
      Abstract: This study is focused on evaluating the advantages of 6.5-kV SiC p-i-n diodes in a 4.16-kV, 8-MVA neutral point clamped (NPC) voltage source converter. Electrothermal models of the power semiconductors are elaborated based on measurement data of a SiC diode module prototype, as well as of commercial Si devices. These models are integrated into a converter simulation, where the junction temperatures of each device are used to determine the maximum power output under different device configurations. For the analysis, a parallel connection of two 6.5-kV insulated-gate bipolar transistors (IGBTs) as well as a series connection of two 3.3-kV IGBTs are considered as switches. The influence of the current change rate during the IGBT turn-on is also studied. SiC p-i-n diodes are used as a replacement for the NPC diodes of the converter and as antiparallel diodes in IGBT modules. The results obtained indicate that an increase in the output power of 17% can be achieved using SiC NPC diodes for the studied current change rates. Alternatively, for a constant output power, the switching frequency of the converter can be increased by 69%, reducing the converter size and system costs by the use of smaller filters.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Wide-Range Soft-Switching PWM Three-Level Combined DC–DC Converter
           Without Added Primary Clamping Devices
    • Authors: Shi; Y.;Yang, X.;
      Pages: 5157 - 5171
      Abstract: This paper proposes a novel wide-range soft-switching pulse-width modulation three-level (TL) combined dc–dc converter characterized with no added primary clamping devices and reduced output inductance value. It is well suited for high input voltage dc–dc industrial applications due to following desirable features: all the switches sustain half of the input voltage; off state voltage of the switches is directly clamped by the bulky input capacitors, and no added primary clamping devices such as clamping diodes, flying capacitors, are required; TL waveform before output filter can be achieved, which significantly reduces the value of the output inductance; the modified phase-shift control method can be utilized to achieve wide output range. The converter can obtain zero-voltage switching (ZVS) for all power switches in wide load range; furthermore, less conduction loss is added to achieve ZVS. The operation and theoretical analysis of the proposed converter are presented. Experiments are carried out to validate the proposed converter, and efficiency curves are tested and given.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Power Router for Meshed Systems Based on a Fractionally Rated Back-to-Back
    • Authors: Kandula; R.;Iyer, A.;Moghe, R.;Hernandez, J.E.;Divan, D.;
      Pages: 5172 - 5180
      Abstract: Increasing energy demand and growth of wind generation have significantly increased the stress on the electric grid. The low investment in transmission infrastructure necessitates adoption of methods for efficient use of existing resources. Power converter-based FACTS devices, capable of dynamic power-flow control, have been the preferred solution to maximize utilization of existing infrastructure, but implementation of traditional FACTS solutions at transmission level voltages is complex and cost prohibitive. This paper proposes a power router (PR) for dynamic power-flow control in a meshed network. The proposed PR is realized by augmenting a transformer with a fractionally rated back-to-back converter. The main advantages of the proposed converter are the fractional converter rating and reduced low-frequency transformer requirement compared to the traditional FACTS solutions. This paper outlines the proposed PR topology, control range, controller design and demonstrates the functionality through simulation and experimental results.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • A Novel Single-SiC-Switch-Based ZVZCS Tapped Boost Converter
    • Authors: Choi; B.H.;Lee, S.W.;Thai, V.X.;Rim, C.T.;
      Pages: 5181 - 5194
      Abstract: A new single-active-switch-based zero voltage and zero current switching (ZVZCS) tapped boost converter is proposed. For the ZVZCS operation of the converter, three diodes and two capacitors were added to an ordinary tapped boost converter. When turned ON, the active switch is in zero current switching with the help of leakage inductance of a tapped inductor. When turned OFF, the energy of the leakage inductance is transferred to a snubber capacitor through a diode, which results in zero voltage switching of the active switch. Then the energy of the snubber capacitor is retrieved by a recovery capacitor connected to the tapped inductor. Different from most conventional soft switching converters that need at least two active switches, the proposed converter requires only one active switch such as JFET and MOSFET to guarantee ZVZCS operation for wide operating ranges of duty cycle, load current, and input voltage. The voltage stress of the active switch is always less than the load voltage, and soft switching turn-on and off is achieved without cumbersome current or voltage sensing, which could not be obtained from quasi-resonant converters that also have an active switch. Furthermore, the dc voltage gain of the proposed converter is quite robust against load change and is determined only by duty cycle like a canonical boost converter; hence, it can be even open-loop controlled. All the diodes are in ZVZCS as well, and all the components except an output diode have the voltage stress less than the load voltage. In this paper, the voltage stress of the output diode was selected to have two times the load voltage. A detailed analysis for the continuous conduction mode and the design procedures of the proposed converter is fully established, and experimentally verified for a 450-W prototype over the input voltage of 100–250 V, achieving 98.1% of maximum efficiency at the switching frequency of 100 kHz with a SiC JFET. Due to its versatile- soft switching characteristics, the proposed scheme can be generally applied to high-frequency and high-efficiency dc–dc converters as well as power factor correctors.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • An Electrolytic Capacitor-less Bi-Directional EV On-Board Charger Using
           Harmonic Modulation Technique
    • Authors: Shin; C.-J.;Lee, J.-Y.;
      Pages: 5195 - 5203
      Abstract: This paper suggests a new electrolytic capacitor-less bi-directional on-board charger for electric vehicle. It has a cascade structure of constant frequency resonant converter for electrical isolation and DCM buck/boost converter for charging/discharging control and input harmonic regulation. Harmonic modulation technique is also proposed to obtain a high power factor and structure change method has been adopted to cope with a wide line voltage condition. Harmonic regulation and charging/discharging control can be accomplished with very simple control algorithm so that high performance controller is not required. Its feasibility has been verified with a 3-kW prototype.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • A Fast and Generalized Space Vector Modulation Scheme for Multilevel
    • Authors: Deng; Y.;Teo, K.H.;Duan, C.;Habetler, T.G.;Harley, R.G.;
      Pages: 5204 - 5217
      Abstract: This paper presents a fast and generalized space vector pulse width modulation (SVPWM) scheme for any multilevel inverter. The SVPWM scheme generates all the available switching states and switching sequences based on two simple and general mappings, and calculates the duty cycles simply as if for a two-level SVPWM, thus independent of the level number of the inverter. Because the switching states, duty cycles, and switching sequences are all obtained by simple calculation in the proposed SVPWM scheme, no lookup table is needed and the scheme is computationally fast. The generalized method of generating the switching states (first mapping), calculating the duty cycles, and determining the switching sequence (second mapping) is described in this paper. The scheme is suitable for any reference vector with any modulation index, and can be conveniently extended to meet specific requirements, such as symmetric switching sequences. Compared with prior methods, the SVPWM scheme proposed in this paper provides two more degrees of freedom, i.e., the adjustable switching sequences and duty cycles, thus offering significant flexibility for optimizing the performance of multilevel inverters. The influence of redundant switching sequences in the output phase voltage of inverters is demonstrated for a nine-level inverter. This paper also thoroughly compares the proposed SVPWM scheme with prior methods. Both simulation and experimental results are given.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • PLL-Based Seamless Transfer Control Between Grid-Connected and Islanding
           Modes in Grid-Connected Inverters
    • Authors: Tran; T.-V.;Chun, T.-W.;Lee, H.-H.;Kim, H.-G.;Nho, E.-C.;
      Pages: 5218 - 5228
      Abstract: This paper proposes a phase-locked loop (PLL)-based seamless transfer control method between grid-connected and islanding modes in a three-phase grid-connected inverter. The PLL is used to synchronize the phase of the load voltage to a grid voltage in grid-connected operation, and to generate an angle with the desired frequency in islanding operation. The stability of both the grid current loop for grid-connected operation and the load voltage control loop for islanding operation is analyzed. The phase and magnitude of the load voltage are successively matched to the grid voltage for a seamless transfer from islanding to grid-connected operation. When grid voltage sag occurs, an operating sequence including a PLL operation is suggested in order to transfer smoothly to islanding operation and to provide a stable and seamless voltage to a sensitive load under the voltage sag condition. The simulation and experimental results are carried out to verify the effectiveness of the proposed algorithm.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Closed-Form Expressions for Minimizing Total Harmonic Distortion in
           Three-Phase Multilevel Converters
    • Authors: Hong; D.;Bai, S.;Lukic, S.M.;
      Pages: 5229 - 5241
      Abstract: The total harmonic distortion (THD) of a waveform is a standard way to quantify its deviation from a sinusoid. In three-phase systems, we are interested in minimizing 3THD: the component of THD produced by odd nontriplen harmonics. However, its definition involves an infinite sum, making it difficult to evaluate and analyze. This paper solves the problem of finding equivalent closed-form expressions for the 3THD of a staircase waveform. In particular, two expressions are rigorously derived, which reveal 3THD to be a piecewise differentiable function. One expression is shorter but describes the pieces implicitly. The other is longer but describes the pieces explicitly. We minimize 3THD using the closed-form expression and provide a comparison with previous techniques. Finally, we provide experimental results that show close agreement with the theoretical results.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • A New Half-Bridge Winding Compensation-Based Power Conditioning System for
           Electric Railway with LQRI
    • Authors: Hu; S.;Zhang, Z.;Li, Y.;Luo, L.;Cao, Y.;Rehtanz, C.;
      Pages: 5242 - 5256
      Abstract: Facing the challenges brought by the negative sequence current (NSC) pollution in power supply system of electric railway, a new topology named half-bridge winding compensation-based railway power conditioner (HBWCRPC) without auxiliary step-down transformer is proposed to suppress the NSC injected into the public networks. It has the advantages of high integration, low losses, and more functions. The compensation principle is discussed, and its physical interpretation is presented. Besides, the mechanism of the voltage perturbation and its various representations in steady state are analyzed. Considering the complexity of voltage perturbation, an optimal control method is adopted to improve the robustness of the control system, and a linear quadratic regulator with integral action, which is applicable for this system, is designed. Finally, simulation and experiment results validate the HBWCRPC system and its control method.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Determining Far-Field EMI From Near-Field Coupling of a Power Converter
    • Authors: Chen; H.;Wang, T.;Feng, L.;Chen, G.;
      Pages: 5257 - 5264
      Abstract: The highly frequent switching of semiconductor devices in power converters is often the source of significant conducted and radiated electromagnetic interference (EMI). In order to understand how radiated EMI is emitted from the noise source, this paper first analyzes the generation of EMI currents of a power converter, and then explains that the far-field radiated EMI emission of a power converter is due to the radiation of common-mode current on attached cables, which is driven by the electric near-field coupling between the printed circuit board and the attached cables of the converter. Based on this idea, an estimate model of the far-field radiated EMI emission of a power converter is developed. By using transverse electromagnetic cell measurements and full-wave numerical calculations, the far-field radiated EMI emissions of a buck converter with different cable lengths are estimated. The estimated results are compared with the measured results from 3-m semianechoic chamber tests with the buck converter, confirming the validity of the model.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Analysis and Suppression of Leakage Current in
           Cascaded-Multilevel-Inverter-Based PV Systems
    • Authors: Zhou; Y.;Li, H.;
      Pages: 5265 - 5277
      Abstract: The transformerless cascaded multilevel inverter (CMI) is considered to be a promising topology alternative for low-cost and high-efficiency photovoltaic (PV) systems. However, the leakage current issue resulted from the parasitic capacitors between the PV panels and the earth remains a challenging in designing a reliable CMI-based PV system. In this paper, the leakage current paths in PV CMI are analyzed and the unique features are discussed. Two filter-based suppression solutions are then presented to tackle the leakage current issue in different PV CMI applications. Simplified leakage current analytical models are derived to study the suppression mechanisms and design the suppression filters. Study cases are demonstrated for each of the solutions with filter design example, simulation and experimental verifications.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Rapid Prototyping of a Low-Cost Solar Array Simulator Using an
           Off-the-Shelf DC Power Supply
    • Authors: Gadelovits; S.;Sitbon, M.;Kuperman, A.;
      Pages: 5278 - 5284
      Abstract: A method of rapid prototyping of a solar array simulator, based on low cost, off-the-shelf components is proposed in the paper. A commercial constant output voltage switching power supply is utilized as a power stage. It is shown that it is possible to gain control over output voltage of such a device by injecting variable analog voltage into the voltage feedback loop of the supply. As a result, by sensing the power supply output current and varying the injected voltage it is possible to change the output voltage according to a predefined relation and hence any static I–V curve may be emulated by the device. For simulating a solar array output characteristics, the desired I–V curve may be either digitized from a manufacturer provided datasheet, obtained experimentally or estimated from three basic current–voltage pairs (open circuit, short circuit, and maximum power points) using a dedicated algorithm. In order to demonstrate the proposed method, a prototype was designed and built based on available low-cost commercial components. Dynamic characteristics of the prototype were experimentally evaluated and three static I–V curves of a commercial solar panel were simulated. The resulting I–V output characteristics were shown to closely resemble datasheet I–V curves.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Center-Cell Concentration Structure of a Cell-to-Cell Balancing Circuit
           With a Reduced Number of Switches
    • Authors: Kim; M.-Y.;Kim, J.-H.;Moon, G.-W.;
      Pages: 5285 - 5297
      Abstract: Among the various cell balancing circuits for series-connected batteries, the bidirectional cell-to-cell balancing structure using two switches per cell shows good balancing ability. However, an increase in the number of switches leads to an increase in both cost and size. To reduce the number of switches, this paper proposes a new cell-to-cell balancing circuit with a center-cell concentration structure. The proposed circuit collects the charges of an overcharged cell into the center cell, and then the collected charges are redistributed to the other cells. The proposed circuit has a unidirectional balancing structure with single switch per cell. However, it can achieve competitive balancing ability when compared with the bidirectional structure. In this paper, the operational principles of the proposed circuit are analyzed, and a comparison between the conventional and proposed circuits is shown. To verify the validity of the proposed circuit, experiments with 15.5-Ah batteries are carried out, and the experimental results demonstrate the improved cell balancing ability although a single switch is used per cell.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • On the Voltage Ripple Reduction Control of the Linear Switched Reluctance
           Generator for Wave Energy Utilization
    • Authors: Pan; J.F.;Zou, Y.;Cheung, N.;Cao, G.-z.;
      Pages: 5298 - 5307
      Abstract: This paper discusses about the voltage output ripple reduction and error minimization for the direct-drive, linear switched reluctance generator (LSRG)-based wave power generation system. First, the concept of the LSRG-based wave power generation system is studied. According to the characteristics of the LSRG, the suitable drive circuit dedicated to proper current excitation and generation is established. Second, the reasons that cause voltage output ripples are investigated. To reduce the remarkable ripples from phase current commutations, a current distribution function (CDF) is proposed based on the minimized copper loss principle. Third, the dual-loop control strategy with current and voltage as the inner and outer loop is constructed, implemented with the proposed CDF. Theoretical bases of the control strategy are derived. The simulation results prove that the proposed control algorithm is capable of voltage ripple suppression and error reduction within the range of ±0.5 V over the entire operation speed for wave energy extraction, validated by experimental verification.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Predictive Control of a Three-Level Boost Converter and an NPC Inverter
           for High-Power PMSG-Based Medium Voltage Wind Energy Conversion Systems
    • Authors: Yaramasu; V.;Wu, B.;
      Pages: 5308 - 5322
      Abstract: In this paper, a new medium voltage power converter topology using a diode rectifier, three-level boost (TLB) converter, and neutral-point-clamped (NPC) inverter is proposed for a high-power permanent magnet synchronous generator-based wind energy conversion system. The generator-side TLB converter performs the maximum power point tracking and balancing of dc-link capacitor voltages, while the grid-side NPC inverter regulates the net dc-bus voltage and reactive power to the grid. A significant improvement in the grid power quality is accomplished as the NPC inverter no longer controls the dc-link neutral point voltage. A model predictive strategy is proposed to control the complete system where the discrete-time models of the proposed power electronic converters are used to predict the future behavior of control variables. These predictions are evaluated using two independent cost functions, and the switching states which minimize these cost functions are selected and applied to the generator- and grid-side converters directly. In order to comply with the high-power application, the switching frequencies of the TLB converter and NPC inverter are minimized and maintained below 1.5 and 1 kHz, respectively. The proposed topology and control strategy are verified through MATLAB simulations on a 3-MW/3000-V/577-A system and dSPACE DS1103-based experiments on 3.6-kW/208-V/10-A prototype.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Advanced Cophase Traction Power Supply System Based on Three-Phase to
           Single-Phase Converter
    • Authors: He; X.;Shu, Z.;Peng, X.;Zhou, Q.;Zhou, Y.;Zhou, Q.;Gao, S.;
      Pages: 5323 - 5333
      Abstract: An advanced cophase traction power supply system is proposed to solve the power quality problems of the traditional traction power supply system, such as unbalance, reactive power, and harmonics to three-phase industrial grid. The three-phase to single-phase converter-based substation is adopted in this system, which can transfer active power from three-phase grid to single-phase catenary and compensate reactive power and harmonics of the locomotives. One catenary section could be utilized in the advanced cophase system instead of the multiple split sections in traditional system. The neutral sections and problems caused by them in traditional system could be avoided. In this paper, the characteristics of the advanced cophase system and the automatic current-sharing control algorithm of three-phase to single-phase converter are studied and analyzed. The simulation and experimental results verify the viability and effectiveness of the proposed system.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Black-Box Model, Identification Technique and Frequency Analysis for PEM
           Fuel Cell With Overshooted Transient Response
    • Authors: Raga; C.;Barrado, A.;Lazaro, A.;Fernandez, C.;Valdivia, V.;Quesada, I.;Gauchia, L.;
      Pages: 5334 - 5346
      Abstract: Fuel cells are one of the most promising energy sources, especially for onboard applications. However, fuel cells present several drawbacks, such as slow dynamic response, load-dependent voltage, and unidirectional power flow, which cause an inappropriate vehicle operation. So, secondary energy sources and power converters must be implemented in order to satisfy fast changes in the current load and to store the energy delivered by the load if regenerative braking is intended. Taking into account the number and nature of the power converters, loads, secondary energy sources, and the possibilities for the control strategies, the design of a power distribution architecture based on fuel cells for transport applications is a complex task. In order to address these architectures, modeling and simulation design tools at system level are essential. This paper proposes a complete fuel cell black-box model which reproduces the behavior of a commercial fuel cell with overshooted transient response. The identification technique applied to parameterize the model components, based on manufacturer's datasheets and a test based on load steps, is explained thoroughly. In addition, if only the fuel cell frequency response and manufacturer's datasheet are available, an alternative parameterization methodology based on the fuel cell frequency response is presented. The fuel cell black-box model is validated experimentally using a commercial proton exchange membrane fuel cell. Two different parameterizations are carried out with the aim of verifying the robustness of both the fuel cell model and the proposed identification methodology.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • ILST Control Algorithm of Single-Stage Dual Purpose Grid Connected Solar
           PV System
    • Authors: Singh; B.;Jain, C.;Goel, S.;
      Pages: 5347 - 5357
      Abstract: This paper presents a single-stage, three-phase grid connected solar photovoltaic (SPV) system. The proposed system is dual purpose, as it not only feeds extracted solar energy into the grid but it also helps in improving power quality in the distribution system. The presented system serves the purpose of maximum power point tracking (MPPT), feeding SPV energy to the grid, harmonics mitigation of loads connected at point of common coupling (PCC) and balancing the grid currents. The SPV system uses a three-phase voltage source converter (VSC) for performing all these functions. An improved linear sinusoidal tracer (ILST)-based control algorithm is proposed for control of VSC. In the proposed system, a variable dc link voltage is used for MPPT. An instantaneous compensation technique is used incorporating changes in PV power for fast dynamic response. The SPV system is first simulated in MATLAB along with Simulink and sim-power system toolboxes, and simulated results are verified experimentally. The proposed SPV system and its control algorithm are implemented in a three-phase distribution system for power quality improvement and improved utilization of VSC. The total harmonics distortions (THDs) of grid currents and PCC voltages are observed within IEEE-929 and IEEE-519 standards.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Comparison and Analysis of Single-Phase Transformerless Grid-Connected PV
    • Authors: Freddy; T.;Rahim, N.A.;Hew, W.-P.;Che, H.S.;
      Pages: 5358 - 5369
      Abstract: Leakage current minimization is one of the most important considerations in transformerless photovoltaic (PV) inverters. In the past, various transformerless PV inverter topologies have been introduced, with leakage current minimized by the means of galvanic isolation and common-mode voltage (CMV) clamping. The galvanic isolation can be achieved via dc-decoupling or ac-decoupling, for isolation on the dc- or ac-side of the inverter, respectively. It has been shown that the latter provides lower losses due to the reduced switch count in conduction path. Nevertheless, leakage current cannot be simply eliminated by galvanic isolation and modulation techniques, due to the presence of switches’ junction capacitances and resonant circuit effects. Hence, CMV clamping is used in some topologies to completely eliminate the leakage current. In this paper, several recently proposed transformerless PV inverters with different galvanic isolation methods and CMV clamping technique are analyzed and compared. A simple modified H-bridge zero-voltage state rectifier is also proposed, to combine the benefits of the low-loss ac-decoupling method and the complete leakage current elimination of the CMV clamping method. The performances of different topologies, in terms of CMV, leakage current, total harmonic distortion, losses and efficiencies are compared. The analyses are done theoretically and via simulation studies, and further validated with experimental results. This paper is helpful for the researchers to choose the appropriate topology for transformerless PV applications and to provide the design principles in terms of common-mode behavior and efficiency.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Unified Synthesis of Tapped-Inductor DC-to-DC Converters
    • Authors: Williams; B.W.;
      Pages: 5370 - 5383
      Abstract: Tapped-inductor variations of single-switch, single-diode, dc-to-dc converters are categorized based on a new unified sequential circuit topology and mathematical transformation approach, all seeded from a basic buck–boost converter and its transfer function. Classification focuses on identifying two different ac circuit coupled inductor arrangements of the basic buck–boost dc-to-dc converter. Subsequent dc circuit sequential manipulation yields all 11 known, documented, in theory, in simulation and practically, tapped-inductor dc-to-dc converter topologies. The procedure not only generates sequences of topologies, but also generates the voltage transfer functions without recourse to analysis of the circuit internal operating mechanisms. Consequently, two converter classes group the 11 known tapped-inductor topologies, which is at least one fewer topology classes than universally accepted. The methodology yields two new classes of three and ten coupled inductor converter topologies, all with new transfer functions. The new analysis approach is adaptable to the analysis of all single-switch, single-diode, (noncoupled inductor), dc-to-dc converters (single and two inductor topologies), formulated from the basic buck–boost converter.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Inductor Current Zero-Crossing Detector and CCM/DCM Boundary Detector for
           Integrated High-Current Switched-Mode DC–DC Converters
    • Authors: Michal; V.;
      Pages: 5384 - 5391
      Abstract: This paper presents two circuits that allow us to accurately detect either the inductor current zero crossing, or the continuous/discontinous conduction modes boundary in the switched-mode dc–dc converters. Achieved detection accuracy allows us to improve the control and efficiency of the integrated high-output current converters, i.e., converters with low-resistance power switches. Detection is based on the voltage zero-cross detector, which provides ideally zero input-referred offset and very fast results. The concept of voltage polarity detector is based on the association of a dynamic current mirror and a simple autozero comparator. This paper describes the main concept of both circuits, aspects of the design allowing us to achieve high accuracy, and presents obtained results. Circuits’ performances are demonstrated on the integrated step-down dc–dc converter with $I_{bf OUT}$ = 2.5 A 30-mΩ NMOS power stage. Measured accuracy of the detection is in order of
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • A 0.18-µm CMOS, 91%-Efficiency, 2-A Scalable Buck-Boost
           DC–DC Converter for LED Drivers
    • Authors: Malcovati; P.;Belloni, M.;Gozzini, F.;Bazzani, C.;Baschirotto, A.;
      Pages: 5392 - 5398
      Abstract: This paper presents a buck-boost dc–dc converter for LED drivers capable of delivering an output current ranging from 0.1to 2 A and a variable output voltage ranging between 2 and 5 V, starting from an input voltage spanning from 2.7 to 5.5 V. The dc–dc converter, realized in a 0.18-µm CMOS technology with 5-V option, occupies an area of 4 mm $^{2}$ including pads. The circuit features automatic mode switching and dynamic sizing of the power transistors to achieve a peak efficiency of 91%. With a switching frequency of 2.5 MHz, the achieved line regulation is lower than 0.1% V $^{-1}$ and the output voltage ripple is less than 10 mV. The obtained turn-on and load transient settling time are lower than 40 µs, thus allowing pulsed operation of the LEDs, as well as switching among LEDs of different colors.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Supercapacitor Sizing Based on Desired Power and Energy Performance
    • Authors: Kuperman; A.;Mellincovsky, M.;Lerman, C.;Aharon, I.;Reichbach, N.;Geula, G.;Nakash, R.;
      Pages: 5399 - 5405
      Abstract: In this paper, instantaneous power and energy capabilities of supercapacitor (SC) connected to a power element are derived for an arbitrary power profile, given either in analytical or statistical distribution form. A class of applications is considered where the device is used as deeply cycled energy storage with significant capacity, absorbing/supplying the whole power flow or its significant component rather than shaving low-energy high-frequency peaks. The analytical derivation of SC behavior is based on simple RC model with parameters taken from a manufacturer datasheet. It is shown that the commonly adopted “state-of-charge” indication based on terminal voltage only is insufficient to reflect the energy balance for both charging and discharging; hence an alternative definition of “state-of-energy” is proposed for each direction of energy flow, depending on both instantaneous power and terminal voltage. A simplified quick noniterative sizing procedure is proposed at the expense of a slightly oversized SC. Comprehensive example is provided in order to reinforce the proposed method of analyzing SC performance and demonstrate sizing procedure.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Postfault Operation of an Asymmetrical Six-Phase Induction Machine With
           Single and Two Isolated Neutral Points
    • Authors: Che; H.S.;Duran, M.J.;Levi, E.;Jones, M.;Hew, W.-P.;Rahim, N.A.;
      Pages: 5406 - 5416
      Abstract: The paper presents a study of postfault control for an asymmetrical six-phase induction machine with single and two isolated neutral points, during single open-phase fault. Postfault control is based on the normal decoupling (Clarke) transformation, so that reconfiguration of the controller is minimized. Effect of the single open-phase fault on the machine equations under this control structure is discussed. Different modes of postfault operation are analyzed and are further compared in terms of the achievable torque and stator winding losses. Validity of the analysis is verified using experimental results obtained from a six-phase induction motor drive prototype.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • A Novel Direct Torque and Flux Control Method of Matrix Converter-Fed PMSM
    • Authors: Xia; C.;Zhao, J.;Yan, Y.;Shi, T.;
      Pages: 5417 - 5430
      Abstract: A novel direct torque and flux control strategy is proposed for matrix converter (MC)-based permanent-magnet synchronous motor (PMSM) drive systems. The proposed method allows the use of all MC switching states including the rotation vectors, and effectively controls input and output variables of the MC. Mapping relationships between MC output voltage vectors and change rates of motor torque and flux, and those between MC input current vectors and change rates of grid reactive charge are derived. Then, four enhanced switching tables are established by means of discretizing and averaging, in which changes of torque, flux and input reactive charge corresponding to all MC switching states can be shown explicitly. Based on the tables, an optimal selection of switching states can be achieved by the proposed method. Numerical simulations and experiments with a prototype are carried out. The results show good performance of the proposed method with small torque and flux ripples, low distortion input currents, and fast dynamic response.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • PWM Strategies for Common-Mode Voltage Reduction in Current Source Drives
    • Authors: Shang; J.;Li, Y.W.;Zargari, N.R.;Cheng, Z.;
      Pages: 5431 - 5445
      Abstract: The common-mode voltage (CMV) in the motor drive system could damage the motor insulation and induce destructive bearing current. Various reduced CMV space vector modulation (RCMV SVM) methods have been proposed in both voltage source converter (VSC) and current source converter systems. Most of them reduce the CMV by avoiding the use of zero-state vectors. Recently, a zero-state vector selection strategy for CMV reduction in CSCs has been proposed, which allows the use of zero-state vectors and achieves reduced CMV without affecting the modulation index range and the harmonics performance of converters. This paper further investigates three possible zero-state vector selection strategies in RCMV SVM for current source drives where the PWM CSR and CSI are connected back to back. Among the three methods, Method 1 and Method 2 are suitable for CMV peak value minimization, while Method 3 is proposed for the average CMV reduction. These methods can then be considered for different types of drives (with or without isolation transformer) to reduce the insulation stress or to limit the resonance in the common mode circuit. Details of the three zero-state vectors selection methods are presented. Both simulation and experimental results are provided to verify their effectiveness.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Inductor Geometry With Improved Energy Density
    • Authors: Cui; H.;Ngo, K.D.T.;Moss, J.;Lim, M.H.F.;Rey, E.;
      Pages: 5446 - 5453
      Abstract: The “constant-flux” concept is leveraged to achieve high magnetic-energy density, leading to inductor geometries with height significantly lower than that of conventional products. Techniques to shape the core and to distribute the winding turns to shape a desirable field profile are described for the two basic classes of magnetic geometries: those with the winding enclosed by the core and those with the core enclosed by the winding. A relatively constant flux distribution is advantageous not only from the density standpoint, but also from the thermal standpoint via the reduction of hot spots, and from the reliability standpoint via the suppression of flux crowding. In this journal paper on a constant-flux inductor (CFI) with enclosed winding, the foci are operating principle, dc analysis, and basic design procedure. Prototype cores and windings were routed from powder-iron disks and copper sheets, respectively. The design of CFI was validated by the assembled inductor prototype.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Influence of Inner Skin- and Proximity Effects on Conduction in Litz Wires
    • Authors: Roskopf; A.;Bar, E.;Joffe, C.;
      Pages: 5454 - 5461
      Abstract: For inductive components such as coils, inductors or transformers, litz wires with isolated strands are used to decrease conduction losses in applications with higher operating frequencies. Depending on the inner structure of these wires, the frequency dependent losses differ extremely. Until now simulations have not sufficiently matched experimental measurements. The usual simulation approach has been to assume the initial current values in all strands in the litz wire to be the same. In this paper, a 3-D simulation of the connector allows the determination of the current values depending on the position of the strands in the wire. This current distribution is transferred to a 2-D rotationally symmetric simulation of the system (windings, coils, etc.). The current values are permuted between different strands to simulate the twisting of strands inside the litz wire. With this new method a very good agreement with measured losses was achieved and demonstrates how simulation allows one to improve the performance of litz wires.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Design and Characterization of Wireless Power Links for
           Brain–Machine Interface Applications
    • Authors: Wu; R.;Li, W.;Luo, H.;Sin, J.K.O.;Yue, C.C.;
      Pages: 5462 - 5471
      Abstract: In this paper, the design of an inductive power link (IPL) for wireless power transfer (WPT) in brain–machine interface (BMI) applications is thoroughly studied. The constraints and requirements of BMI applications are analyzed. By theoretical derivations, the relationships between the IPL performances and its electrical parameters are determined. The design guidelines for the IPL physical parameters are then obtained through experimental characterizations. Experimental results show that with proper IPL design, the efficiency can be improved from the previously reported values of 29.9% and 4.3% to 33.1% and 9.2% for BMI WPT distances of 5 and 12.5 mm, respectively.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • A TRIAC Dimmable Single-Switch Electronic Ballast With Power Factor
           Correction and Lamp Power Regulation
    • Authors: Lam; J.C.W.;Jain, P.K.;
      Pages: 5472 - 5485
      Abstract: With the global concerns on the issue of how to conserve the limited energy resources, compact fluorescent lamps (CFLs) have been forced in a lot of countries to replace the power-hungry incandescent lamps to reduce the energy cost. However, conventional passive power factor corrected electronic ballasts used in CFLs suffer two major drawbacks: 1) they are unable to achieve close-to-unity power factor and 2) they are unable to provide the same amount of light intensity under fluctuating line voltage. This paper proposed a simple lamp power regulation method for a very high-power factor single-switch electronic ballast, which allows the electronic ballast to maintain almost constant lamp power at its full-power condition for a wide range of the input voltage by controlling the dc-link voltage of the ballast power circuit through duty ratio control. When a TRIAC phase-cut dimmer is used to dim the CFL, the dc-link voltage regulation control loop is deactivated; so that the lamp power decreases accordingly during dimming. The analysis and operating principles of the controller are discussed in this paper. MATLAB, PSIM simulation, and experimental results are provided to highlight the merits of the proposed work.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • $bm{dupsilon/+dt}$++Rectifier+as+a+PFC+for+Electronic+Ballast+Application&rft.title=IEEE+Transactions+on+Power+Electronics&rft.issn=0885-8993&;Jirasereeamornkul,++K.;Kazimierczuk,++M.K.;">Implementation of a DC-Side Class-DE Low-       formulatype="inline"> $bm{dupsilon/ dt}$
            Rectifier as a PFC for Electronic Ballast Application
    • Authors: Ekkaravarodome; C.;Jirasereeamornkul, K.;Kazimierczuk, M.K.;
      Pages: 5486 - 5497
      Abstract: An analysis and design of a single-stage electronic ballast with a dc-side Class-DE low- $dupsilon/dt$ resonant rectifier is studied in this paper to improve a poor power-factor and low line harmonic. The power-factor correction is achieved by utilize an output characteristics of a Class-DE rectifier, which is inserted between the front-end bridge rectifier and the bulk-filter capacitor. The design procedure is based on the principle of the Class-DE rectifier, which also ensures more accurate results and the proposed scheme provided a more systematic and feasible analysis methodology. The active switches can be operated under the soft-switching condition. By employing an electromagnetic interference filter after bridge rectifier, the standard-recovery diode for bridge rectifier can be employed, the cost can be reduced, the conduction angle of the bridge-rectifier diode current was increased, and low line harmonic distortion and a power factor near unity were achieved. The dc-side Class-DE rectifier is driven by a high-frequency current source, which is obtained from the square-wave output voltage of the Class-D series–parallel resonant inverter through an LC-series circuit. A prototype of the ballast, operating at an 84-kHz fixed frequency and a 220-V $_{rm rms}$ , 50-Hz line voltage, was utilized to drive a T8–36 W fluorescent lamp. The validity of this approach was confirmed by simulation and experimental results.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Self-Configurable Current-Mirror Circuit With Short-Circuit and
           Open-Circuit Fault Tolerance for Balancing Parallel Light-Emitting Diode
           (LED) String Currents
    • Authors: Li; S.;Ron Hui, S.Y.;
      Pages: 5498 - 5507
      Abstract: Current imbalance among parallel light-emitting diode (LED) strings could put excessive current and thermal stress on some of the LEDs in the systems, resulting in reduction in system lifetime. For LED road lighting systems, reliability is the paramount factor. This paper first explains how existing current-mirror (CM) circuits cannot cope with LED open-circuit faults and then describes a self-configurable CM circuit that can withstand open-circuit faults in LED systems with parallel LED strings. The ability to withstand open-circuit faults means that the LED systems can still function with reduced luminous output even if one LED string is cut off. The proposed circuit, which retains the feature of not requiring an auxiliary dc power supply, has been practically implemented and successfully tested in a 70-W LED system with three parallel strings.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Feed-Forward Scheme for an Electrolytic Capacitor-Less AC/DC LED Driver to
           Reduce Output Current Ripple
    • Authors: Yang; Y.;Ruan, X.;Zhang, L.;He, J.;Ye, Z.;
      Pages: 5508 - 5517
      Abstract: In order to achieve high-efficiency, high-power-factor, high-reliability, and low-cost, a flicker-free electrolytic capacitor-less single-phase ac/dc light emitting diode (LED) driver is investigated in this paper. This driver is composed of a power-factor-correction (PFC) converter and a bidirectional converter. The bidirectional converter is used to absorb the second harmonic component in the output current of the PFC converter, thus producing a pure dc output to drive the LEDs. The spectrum of the output capacitor voltage of the bidirectional converter is analyzed, indicating that the output capacitor voltage contains harmonic components at multiples of twice the line frequency apart from the dc component and second harmonic component. A feed-forward control scheme with a series of calculation operation is proposed to obtain the desired modulation signal, which contains the corresponding harmonic components, to ensure the bidirectional converter fully absorb the second harmonic current in the output of the PFC converter. Finally, a 33.6 W prototype is fabricated and tested in the lab, and the experiment results show that the proposed control scheme greatly reduces the ripple of the LED driving current.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Predictive Direct Power Control for Three-Phase Grid-Connected Converters
           Without Sector Information and Voltage Vector Selection
    • Authors: Song; Z.;Chen, W.;Xia, C.;
      Pages: 5518 - 5531
      Abstract: In this paper, a predictive direct power control (DPC) method without sector information and voltage vector selection is proposed for three-phase grid-connected converters. Different from conventional predictive direct power controllers, the proposed strategy always adopts fixed voltage vectors, instead of selecting voltage vectors according to the angular information of the grid-voltage vector or the virtual-flux vector. The converter switching time is obtained by minimizing the squared errors of the instantaneous active and reactive power. Switch duty cycles are then calculated and equivalently reconstructed. The proposed strategy not only presents rapid dynamic response due to the use of the predictive controller, but also possesses excellent steady-state performance as a result of duty cycle reconstruction. The main advantage of the proposed control scheme, compared with the classical DPC strategies, is that it is unnecessary to use sector information of the grid-voltage vector, and selection of active voltage vectors is also not required here. Therefore, incorrect selection of voltage vectors and the resulting performance deterioration are surely avoided, without the need of any additional compensation measures. An in-depth comparison and experimental assessment are given to validate the effectiveness of the proposed strategy.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Low Complexity Model Predictive Control—Single Vector-Based
    • Authors: Zhang; Y.;Xie, W.;
      Pages: 5532 - 5541
      Abstract: Finite control set model predictive control (FCS-MPC) is emerging as a powerful control scheme in the control of power converters, because it takes the discrete nature of power converters into account and offers a flexible way to consider various constraints. However, conventional FCS-MPC requires to evaluate a cost function for each discrete switching states, which poses high computational burden. This paper proposes a low-complexity MPC (LC-MPC), which only requires one prediction to find the best voltage vector. The principle of LC-MPC is inherited from prior direct current control (DCC), but has been generalized by identifying its advantages, limitations, and potential application areas. Furthermore, the relationship between LC-MPC and FCS-MPC is studied and it is found that in some cases, the LC-MPC is completely equivalent to FCS-MPC. This paper presents the application example of LC-MPC in power control of three-phase ac/dc converter. To make it a success, the negative conjugate of complex power in synchronous frame is selected as the control variable. Detailed principle of vector selection is introduced and the reason for requiring only one prediction in the proposed LC-MPC is strictly proven using mathematical tools. The proposed LC-MPC is compared with conventional FCS-MPC and its effectiveness is verified by both simulation and experimental results from a two-level ac/dc converter.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Automeasurement of the Inverter Output Voltage Delay Curve to Compensate
           for Inverter Nonlinearity in Sensorless Motor Drives
    • Authors: Shen; G.;Yao, W.;Chen, B.;Wang, K.;Lee, K.;Lu, Z.;
      Pages: 5542 - 5553
      Abstract: In order to improve the performance of sensorless field-oriented controlled motor drives at low speed, the inverter nonlinearity should be compensated for by an accurate voltage error model. This paper proposes a novel method to automatically obtain the total output voltage delay curve, which is a significant part of the inverter voltage error model. Unlike manual measurements of the output delays in earlier literature works, the proposed automatic measurement method achieves low cost in time and labor. Meanwhile, the compensation accuracy based on the automeasured output voltage delay curve is approaching to the performance of compensation by the manual measurement method, far better than the accuracy of compensation by the standard square-wave model at low speed. Moreover, in contrast to other inverter nonlinearity automeasurement methods, the measured results of the proposed method can be applied to compensate for inverter nonlinearities at different switching frequencies. The effectiveness of this method is validated in a voltage source inverter fed induction motor drive system experimentally.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • $T$ -Based+Inductive+Power+Transfer+Power+Supplies&rft.title=IEEE+Transactions+on+Power+Electronics&rft.issn=0885-8993&;Covic,++G.A.;Boys,++J.T.;">An Approximate Dynamic Model of LCL-        Notation="TeX">$T$ -Based Inductive Power Transfer Power
    • Authors: Hao; H.;Covic, G.A.;Boys, J.T.;
      Pages: 5554 - 5567
      Abstract: This paper analyzes the dynamics of an LCL- $T$ -based inductive power transfer power supply, and aims to improve its reference tracking performance for dynamic roadway wireless powering applications using a digital PI controller. An approximate small-signal model of the power supply that describes how the power supply reacts to a perturbation in its input is derived using the generalized state-space averaging technique. The model is verified experimentally and shown to capture the supply dynamics. Limitations of the model and their implications are also discussed. Using the small-signal model, a closed-loop digital PI controller is designed to ensure a fast turn-on of a 20 kHz power supply at no-load in approximately 300 μs with no overshoot in the track current.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Control of Inverters Via a Virtual Capacitor to Achieve Capacitive Output
    • Authors: Zhong; Q-.C.;Zeng, Y.;
      Pages: 5568 - 5578
      Abstract: Mainstream inverters have inductive output impedance at low frequencies (such inverters are called L-inverters). In this paper, a control strategy is proposed to make the output impedance of an inverter capacitive at low frequencies (such inverters are called C-inverters). The proposed control strategy involves the feedback of the inductor current through an integrator, which is actually the impedance of a virtual capacitor. The gain of the integrator or the virtual capacitance is first selected to guarantee the stability of the current feedback loop and then optimized to minimize the total harmonic distortion (THD) of the output voltage. Moreover, some guidelines are developed to facilitate the selection of the filter components for C-inverters. Simulation and experimental results are provided to demonstrate the feasibility and excellent performance of C-inverters, with the filter parameters of the test rig selected according to the guidelines developed. It is shown that, with the same hardware, the lowest voltage THD is obtained when the inverter is designed to be a C-inverter. A by product of this study is that, as long as the current ripples are kept within the desired range, the filter inductor should be chosen as small as possible in order to reduce voltage harmonics. This helps reduce the size, weight, and volume of the inductor and improve the power density of the inverter.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Space Vector Modulation for Three-Level NPC Converter With Neutral Point
           Voltage Balance and Switching Loss Reduction
    • Authors: Jiao; Y.;Lee, F.C.;Lu, S.;
      Pages: 5579 - 5591
      Abstract: This paper investigates the different control objectives, such as loss reduction, neutral point (NP) balance and noise reduction of the space vector modulation (SVM), for the three-level neutral point clamped (NPC) converter. A detailed loss model and simulation model is built for quantitative loss and NP voltage ripple analysis. An improved SVM method is proposed to reduce NP imbalance and switching loss/noise simultaneously. The coordinately selected small vectors consider both the NP charge and the pulse sequence so that the minimized NP ripple and switching events are guaranteed in one switching cycle. In addition, the switching events between switching cycles are also considered to reduce the total switching loss. This method ensures an evenly distributed device loss in each phase leg and also a constant system efficiency under different power factors. The control result for NP balance and loss reduction is verified by using both a simulation model and an experimental prototype on a 200-kVA three-level NPC converter hardware.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Multilevel Direct Power Control—A Generalized Approach for
           Grid-Tied Multilevel Converter Applications
    • Authors: Rivera; S.;Kouro, S.;Wu, B.;Alepuz, S.;Malinowski, M.;Cortes, P.;Rodriguez, J.;
      Pages: 5592 - 5604
      Abstract: This paper presents a generalized multilevel direct power control (ML-DPC) scheme for grid-connected multilevel power converters. The proposed method extends the original DPC operating principle by considering only the closest subset of two-level voltage vectors to the present switching state. The implementation of this principle requires the power derivatives for feedback, which can present numerical problems when applied experimentally, mainly due to high measurement noise sensitivity. Therefore, a derivative estimator is proposed based on the converter–grid model in the synchronous reference frame. In addition, a virtual flux observer is developed to achieve synchronization and improve robustness in the presence of grid voltage harmonics. The proposed method is applicable to any multilevel converter topology of any number of levels. In this paper, simulations and experimental results are presented for a seven-level cascaded H-bridge converter.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Robust Single-Loop Direct Current Control of LCL-Filtered Converter-Based
           DG Units in Grid-Connected and Autonomous Microgrid Modes
    • Authors: Kahrobaeian; A.;Mohamed, Y.A.;
      Pages: 5605 - 5619
      Abstract: This paper presents a robust direct single-loop current control scheme based on structured singular value (μ) minimization approach for induced-capacitor-inductor (LCL)-filtered distributed generation converters in grid-connected and isolated microgrid modes. Unlike the conventional $H_infty$ -based approach, the proposed interface maintains perturbed system stability, under wide range of grid (or microgrid) impedance variation, without the application of any additional damping loops. Moreover, the performance of the perturbed system in terms of grid-voltage and harmonic disturbance rejection can be improved significantly by the adopted method. This is due to the less conservative nature of the μ-synthesis-based solution as it takes advantage of the additional structure introduced to the uncertainty block by the performance criteria. The salient features of the proposed controller are 1) single-loop direct current control of LCL -filtered converters with inherent damping of the LCL filter resonance without any need for additional damping loops; 2) robust stability and active damping performances by mitigating the LCL resonance under wide range of grid (or microgrid) impedance variation; 3) improving the performance of the current controller by removing its dependency on the grid-voltage feed-forward loop by providing high disturbance rejection feature against fundamental and harmonic voltage disturbances; 4) computationally efficient fixed-order structure with minimum sensor requirements (only grid-side currents are needed for feedback control). A comparative theoretical analysis, time-domain simulation results, and experimental test results are presented to show the effectiveness of the proposed control scheme.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Dynamic Analysis and State Feedback Voltage Control of Single-Phase Active
           Rectifiers With DC-Link Resonant Filters
    • Authors: Vasiladiotis; M.;Rufer, A.;
      Pages: 5620 - 5633
      Abstract: Single-phase active rectifiers exhibit an inherent strong second-order current harmonic on their dc-link. The latter is often undesirable from a load point of view and is therefore chosen to be eliminated. A common method is the use of a resonant passive LC filter tuned at the frequency, which increases the order of the system, posing certain difficulties for the voltage control design. This paper presents a comprehensive analysis of the dc-link dynamics. The equations are linearized by means of small variations, and a respective closed-loop regulator is formed utilizing the partial state feedback control theory for pseudocontinuous systems. The control output is fed to an inner current regulator, following the well-known cascaded loop method. The stability of the proposed controller is validated throughout the whole operating point regime and its robustness against system parameter variations is evaluated. A comparison with a conventional controller proves the advantages of the utilized method. The theoretical analysis is verified by means of simulations as well as real-time implementation on an experimental laboratory setup.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • Robust Predictive Control of Grid-Tied Converters Based on Direct Power
    • Authors: Fischer; J.R.;Gonzalez, S.A.;Carugati, I.;Herran, M.A.;Judewicz, M.G.;Carrica, D.O.;
      Pages: 5634 - 5643
      Abstract: This study focuses on the control of instantaneous complex power of a grid-connected voltage-source inverter (VSI). In this study, a new space-vector-modulation-based direct power control approach is proposed: the robust predictive direct power control (RP-DPC). The proposed predictive control algorithm ensures that both, instantaneous real and imaginary powers, track the reference with high speed and accuracy reducing steady-state errors. In order to reduce the total harmonic distortion (THD) in the output currents, a fundamental frequency positive sequence detector is used in conjunction with a prediction grid voltage observer. Comparative simulations and experimental results of a $10$ -kW three-phase grid-connected VSI showing the steady-state and transient performance of the proposed RP-DPC are given. A low THD and balanced output currents are maintained even under severe voltage unbalance conditions.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
  • A Unified Control for the Combined Permanent Magnet Generator and Active
           Rectifier System
    • Authors: Xu; Z.;Zhang, D.;Wang, F.;Boroyevich, D.;
      Pages: 5644 - 5656
      Abstract: This paper presents a unified control method for the combined permanent magnet generator (PMG) and active rectifier that can be used in autonomous power systems such as more-electric aircraft requiring high power density and efficiency. With the proposed control, the system can function well without additional boost inductors and rotor position sensors. The design procedure for the control is presented, including current loops, a voltage loop, and a rotor position estimator loop. Simulation and experimental results show that both the dc-link voltage and the reactive power could be controlled effectively. A system efficiency optimization technique is proposed by selecting the permanent magnet flux linkage and determining the operating points at various load and speed conditions. The power density and efficiency of the PMG and active rectifier system are improved with the unified control.
      PubDate: Oct. 2014
      Issue No: Vol. 29, No. 10 (2014)
School of Mathematical and Computer Sciences
Heriot-Watt University
Edinburgh, EH14 4AS, UK
Tel: +00 44 (0)131 4513762
Fax: +00 44 (0)131 4513327
About JournalTOCs
News (blog, publications)
JournalTOCs on Twitter   JournalTOCs on Facebook

JournalTOCs © 2009-2014