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  Subjects -> ELECTRONICS (Total: 175 journals)
Showing 1 - 200 of 277 Journals sorted alphabetically
Acta Electronica Malaysia     Open Access  
Advances in Biosensors and Bioelectronics     Open Access   (Followers: 7)
Advances in Electrical and Electronic Engineering     Open Access   (Followers: 5)
Advances in Electronics     Open Access   (Followers: 76)
Advances in Magnetic and Optical Resonance     Full-text available via subscription   (Followers: 8)
Advances in Microelectronic Engineering     Open Access   (Followers: 13)
Advances in Power Electronics     Open Access   (Followers: 33)
Advancing Microelectronics     Hybrid Journal  
Aerospace and Electronic Systems, IEEE Transactions on     Hybrid Journal   (Followers: 305)
American Journal of Electrical and Electronic Engineering     Open Access   (Followers: 24)
Annals of Telecommunications     Hybrid Journal   (Followers: 9)
APSIPA Transactions on Signal and Information Processing     Open Access   (Followers: 9)
Archives of Electrical Engineering     Open Access   (Followers: 13)
Autonomous Mental Development, IEEE Transactions on     Hybrid Journal   (Followers: 8)
Bell Labs Technical Journal     Hybrid Journal   (Followers: 28)
Bioelectronics in Medicine     Hybrid Journal  
Biomedical Engineering, IEEE Reviews in     Full-text available via subscription   (Followers: 19)
Biomedical Engineering, IEEE Transactions on     Hybrid Journal   (Followers: 35)
Biomedical Instrumentation & Technology     Hybrid Journal   (Followers: 6)
Broadcasting, IEEE Transactions on     Hybrid Journal   (Followers: 12)
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   (Followers: 1)
Canadian Journal of Remote Sensing     Full-text available via subscription   (Followers: 44)
China Communications     Full-text available via subscription   (Followers: 8)
Chinese Journal of Electronics     Hybrid Journal  
Circuits and Systems     Open Access   (Followers: 15)
Consumer Electronics Times     Open Access   (Followers: 5)
Control Systems     Hybrid Journal   (Followers: 253)
Edu Elektrika Journal     Open Access   (Followers: 1)
Electrica     Open Access  
Electronic Design     Partially Free   (Followers: 104)
Electronic Markets     Hybrid Journal   (Followers: 7)
Electronic Materials Letters     Hybrid Journal   (Followers: 4)
Electronics     Open Access   (Followers: 85)
Electronics and Communications in Japan     Hybrid Journal   (Followers: 10)
Electronics For You     Partially Free   (Followers: 91)
Electronics Letters     Hybrid Journal   (Followers: 26)
Elkha : Jurnal Teknik Elektro     Open Access  
Embedded Systems Letters, IEEE     Hybrid Journal   (Followers: 50)
Energy Harvesting and Systems     Hybrid Journal   (Followers: 4)
Energy Storage Materials     Full-text available via subscription   (Followers: 2)
EPJ Quantum Technology     Open Access  
EURASIP Journal on Embedded Systems     Open Access   (Followers: 11)
Facta Universitatis, Series : Electronics and Energetics     Open Access  
Foundations and Trends® in Communications and Information Theory     Full-text available via subscription   (Followers: 6)
Foundations and Trends® in Signal Processing     Full-text available via subscription   (Followers: 10)
Frequenz     Hybrid Journal   (Followers: 1)
Frontiers of Optoelectronics     Hybrid Journal   (Followers: 1)
Geoscience and Remote Sensing, IEEE Transactions on     Hybrid Journal   (Followers: 185)
Haptics, IEEE Transactions on     Hybrid Journal   (Followers: 4)
IACR Transactions on Symmetric Cryptology     Open Access  
IEEE Antennas and Propagation Magazine     Hybrid Journal   (Followers: 96)
IEEE Antennas and Wireless Propagation Letters     Hybrid Journal   (Followers: 77)
IEEE Journal of Emerging and Selected Topics in Power Electronics     Hybrid Journal   (Followers: 46)
IEEE Journal of the Electron Devices Society     Open Access   (Followers: 9)
IEEE Journal on Exploratory Solid-State Computational Devices and Circuits     Hybrid Journal   (Followers: 1)
IEEE Power Electronics Magazine     Full-text available via subscription   (Followers: 65)
IEEE Transactions on Antennas and Propagation     Full-text available via subscription   (Followers: 69)
IEEE Transactions on Automatic Control     Hybrid Journal   (Followers: 55)
IEEE Transactions on Circuits and Systems for Video Technology     Hybrid Journal   (Followers: 19)
IEEE Transactions on Consumer Electronics     Hybrid Journal   (Followers: 39)
IEEE Transactions on Electron Devices     Hybrid Journal   (Followers: 19)
IEEE Transactions on Information Theory     Hybrid Journal   (Followers: 26)
IEEE Transactions on Power Electronics     Hybrid Journal   (Followers: 70)
IEEE Transactions on Signal and Information Processing over Networks     Full-text available via subscription   (Followers: 11)
IEICE - Transactions on Electronics     Full-text available via subscription   (Followers: 12)
IEICE - Transactions on Information and Systems     Full-text available via subscription   (Followers: 5)
IET Cyber-Physical Systems : Theory & Applications     Open Access   (Followers: 1)
IET Microwaves, Antennas & Propagation     Hybrid Journal   (Followers: 35)
IET Nanodielectrics     Open Access  
IET Power Electronics     Hybrid Journal   (Followers: 45)
IET Smart Grid     Open Access  
IET Wireless Sensor Systems     Hybrid Journal   (Followers: 18)
IETE Journal of Education     Open Access   (Followers: 4)
IETE Journal of Research     Open Access   (Followers: 11)
IETE Technical Review     Open Access   (Followers: 13)
IJEIS (Indonesian Journal of Electronics and Instrumentation Systems)     Open Access   (Followers: 3)
Industrial Electronics, IEEE Transactions on     Hybrid Journal   (Followers: 57)
Industry Applications, IEEE Transactions on     Hybrid Journal   (Followers: 24)
Informatik-Spektrum     Hybrid Journal   (Followers: 2)
Instabilities in Silicon Devices     Full-text available via subscription   (Followers: 1)
Intelligent Transportation Systems Magazine, IEEE     Full-text available via subscription   (Followers: 12)
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: 10)
International Journal of Antennas and Propagation     Open Access   (Followers: 11)
International Journal of Applied Electronics in Physics & Robotics     Open Access   (Followers: 5)
International Journal of Computational Vision and Robotics     Hybrid Journal   (Followers: 6)
International Journal of Control     Hybrid Journal   (Followers: 12)
International Journal of Electronics     Hybrid Journal   (Followers: 7)
International Journal of Electronics and Telecommunications     Open Access   (Followers: 13)
International Journal of Granular Computing, Rough Sets and Intelligent Systems     Hybrid Journal   (Followers: 2)
International Journal of High Speed Electronics and Systems     Hybrid Journal  
International Journal of Image, Graphics and Signal Processing     Open Access   (Followers: 14)
International Journal of Microwave and Wireless Technologies     Hybrid Journal   (Followers: 8)
International Journal of Nano Devices, Sensors and Systems     Open Access   (Followers: 12)
International Journal of Nanoscience     Hybrid Journal   (Followers: 1)
International Journal of Numerical Modelling: Electronic Networks, Devices and Fields     Hybrid Journal   (Followers: 4)
International Journal of Power Electronics     Hybrid Journal   (Followers: 24)
International Journal of Review in Electronics & Communication Engineering     Open Access   (Followers: 4)
International Journal of Sensors, Wireless Communications and Control     Hybrid Journal   (Followers: 10)
International Journal of Systems, Control and Communications     Hybrid Journal   (Followers: 4)
International Journal of Wireless and Microwave Technologies     Open Access   (Followers: 6)
International Transaction of Electrical and Computer Engineers System     Open Access   (Followers: 2)
JAREE (Journal on Advanced Research in Electrical Engineering)     Open Access  
Journal of Biosensors & Bioelectronics     Open Access   (Followers: 3)
Journal of Advanced Dielectrics     Open Access   (Followers: 1)
Journal of Artificial Intelligence     Open Access   (Followers: 10)
Journal of Circuits, Systems, and Computers     Hybrid Journal   (Followers: 4)
Journal of Computational Intelligence and Electronic Systems     Full-text available via subscription   (Followers: 1)
Journal of Electrical and Electronics Engineering Research     Open Access   (Followers: 23)
Journal of Electrical Bioimpedance     Open Access   (Followers: 2)
Journal of Electrical Engineering & Electronic Technology     Hybrid Journal   (Followers: 7)
Journal of Electrical, Electronics and Informatics     Open Access  
Journal of Electromagnetic Analysis and Applications     Open Access   (Followers: 7)
Journal of Electromagnetic Waves and Applications     Hybrid Journal   (Followers: 8)
Journal of Electronic Design Technology     Full-text available via subscription   (Followers: 6)
Journal of Electronics (China)     Hybrid Journal   (Followers: 4)
Journal of Energy Storage     Full-text available via subscription   (Followers: 4)
Journal of Field Robotics     Hybrid Journal   (Followers: 2)
Journal of Guidance, Control, and Dynamics     Hybrid Journal   (Followers: 162)
Journal of Information and Telecommunication     Open Access   (Followers: 1)
Journal of Intelligent Procedures in Electrical Technology     Open Access   (Followers: 3)
Journal of Low Power Electronics     Full-text available via subscription   (Followers: 7)
Journal of Low Power Electronics and Applications     Open Access   (Followers: 9)
Journal of Microelectronics and Electronic Packaging     Hybrid Journal  
Journal of Microwave Power and Electromagnetic Energy     Hybrid Journal  
Journal of Microwaves, Optoelectronics and Electromagnetic Applications     Open Access   (Followers: 10)
Journal of Nuclear Cardiology     Hybrid Journal  
Journal of Optoelectronics Engineering     Open Access   (Followers: 4)
Journal of Physics B: Atomic, Molecular and Optical Physics     Hybrid Journal   (Followers: 28)
Journal of Power Electronics & Power Systems     Full-text available via subscription   (Followers: 11)
Journal of Semiconductors     Full-text available via subscription   (Followers: 5)
Journal of Sensors     Open Access   (Followers: 26)
Journal of Signal and Information Processing     Open Access   (Followers: 9)
Jurnal Rekayasa Elektrika     Open Access  
Jurnal Teknik Elektro     Open Access  
Kinetik : Game Technology, Information System, Computer Network, Computing, Electronics, and Control     Open Access  
Learning Technologies, IEEE Transactions on     Hybrid Journal   (Followers: 12)
Magnetics Letters, IEEE     Hybrid Journal   (Followers: 7)
Majalah Ilmiah Teknologi Elektro : Journal of Electrical Technology     Open Access   (Followers: 2)
Metrology and Measurement Systems     Open Access   (Followers: 5)
Microelectronics and Solid State Electronics     Open Access   (Followers: 18)
Nanotechnology Magazine, IEEE     Full-text available via subscription   (Followers: 33)
Nanotechnology, Science and Applications     Open Access   (Followers: 6)
Nature Electronics     Hybrid Journal  
Networks: an International Journal     Hybrid Journal   (Followers: 6)
Open Journal of Antennas and Propagation     Open Access   (Followers: 8)
Optical Communications and Networking, IEEE/OSA Journal of     Full-text available via subscription   (Followers: 15)
Paladyn. Journal of Behavioral Robotics     Open Access   (Followers: 1)
Power Electronics and Drives     Open Access   (Followers: 1)
Problemy Peredachi Informatsii     Full-text available via subscription  
Progress in Quantum Electronics     Full-text available via subscription   (Followers: 7)
Pulse     Full-text available via subscription   (Followers: 5)
Radiophysics and Quantum Electronics     Hybrid Journal   (Followers: 2)
Recent Advances in Communications and Networking Technology     Hybrid Journal   (Followers: 3)
Recent Advances in Electrical & Electronic Engineering     Hybrid Journal   (Followers: 9)
Research & Reviews : Journal of Embedded System & Applications     Full-text available via subscription   (Followers: 5)
Security and Communication Networks     Hybrid Journal   (Followers: 2)
Selected Topics in Applied Earth Observations and Remote Sensing, IEEE Journal of     Hybrid Journal   (Followers: 53)
Semiconductors and Semimetals     Full-text available via subscription   (Followers: 1)
Sensing and Imaging : An International Journal     Hybrid Journal   (Followers: 2)
Services Computing, IEEE Transactions on     Hybrid Journal   (Followers: 4)
Software Engineering, IEEE Transactions on     Hybrid Journal   (Followers: 75)
Solid-State Circuits Magazine, IEEE     Hybrid Journal   (Followers: 13)
Solid-State Electronics     Hybrid Journal   (Followers: 9)
Superconductor Science and Technology     Hybrid Journal   (Followers: 2)
Synthesis Lectures on Power Electronics     Full-text available via subscription   (Followers: 3)
Technical Report Electronics and Computer Engineering     Open Access  
TELE     Open Access  
Telematique     Open Access  
TELKOMNIKA (Telecommunication, Computing, Electronics and Control)     Open Access   (Followers: 8)
Universal Journal of Electrical and Electronic Engineering     Open Access   (Followers: 6)
Visión Electrónica : algo más que un estado sólido     Open Access   (Followers: 1)
Wireless and Mobile Technologies     Open Access   (Followers: 6)
Wireless Power Transfer     Full-text available via subscription   (Followers: 4)
Women in Engineering Magazine, IEEE     Full-text available via subscription   (Followers: 11)
Електротехніка і Електромеханіка     Open Access  

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Journal Cover
Industry Applications, IEEE Transactions on
Journal Prestige (SJR): 1.02
Citation Impact (citeScore): 4
Number of Followers: 24  
 
  Hybrid Journal Hybrid journal (It can contain Open Access articles)
ISSN (Print) 0093-9994
Published by IEEE Homepage  [191 journals]
  • IEEE Industry Applications Society
    • 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: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • IEEE Transactions On Industry Applications
    • Abstract: Provides a listing of current committee members and society officers.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Information for Authors
    • Abstract: These instructions give guidelines for preparing papers for this publication. Presents information for authors publishing in this journal.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Integrated Planning of a Large-Scale Heat Pump in View of Heat and Power
           Networks
    • Authors: Sergey Klyapovskiy;Shi You;Hanmin Cai;Henrik W. Bindner;
      Pages: 5 - 15
      Abstract: With the present trend toward smart grids and integrated energy systems, the potential benefits achieved by developing integrated planning and operation solutions crossing multiple energy sectors become recently recognizable. This paper investigates the problem of optimal planning for a large-scale heat pump (HP)-a component that links electric and heat utilities together, from an integrated perspective. The proposed method assures an optimal system design with the minimum expense on both capital expenditure and operating expense for the heat network and the electrical network, given that the optional HP locations are already provided together with other technical and economic information needed for executing the planning exercise. The operational flexibility of the HP, i.e., the ability of reducing its electricity consumption from time to time, is also integrated into the planning method. The value of the proposed solution is demonstrated throughout a case study that resembles a live planning exercise conducted for a green field area in Denmark.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Automated Distributed Electric Vehicle Controller for Residential Demand
           Side Management
    • Authors: Samy Faddel;Osama A. Mohammed;
      Pages: 16 - 25
      Abstract: Electric vehicles (EVs) are recently gaining traction in the power sector due to various challenges and opportunities they provide to utility operators. For electric utilities that incorporate demand side management (DSM) programs, EVs could become either a burden or an advantage depending on their charging control strategy and the signaling of the DSM program. This paper proposes a decentralized fuzzy-based controller to successfully integrate and coordinate the charging of EVs that ensures fair charging of EVs at different point of connections (POCs) in the distribution grid where voltage conditions might not be the same. The controller operates in an autonomous mode that reduces the monetary cost of the communication overhead and preserves bandwidth. The proposed controller takes into consideration the owner requirements in terms of energy needed and time to charge, the voltage at the POC with the grid, and the pricing signal coming from the utility. The controller is tested under different DSM programs that exist in the literature. This paper also proposes a new DSM program that is capable of benefiting from EVs as prosumers that can provide grid services. The controller's performance was validated through MATLAB simulations that showed the controller's ability to successfully coordinate the charging of EVs in a fair manner and achieve flat system peaks without any rebound effect. The controller was also successfully tested in the presence of voltage control units, such as capacitor banks, and in the presence of distributed generations.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Aggregation of Users in a Residential/Commercial Building Managed by a
           Building Energy Management System (BEMS)
    • Authors: Luigi Martirano;Giuseppe Parise;Giacomo Greco;Matteo Manganelli;Ferdinando Massarella;Marta Cianfrini;Luigi Parise;Paolo di Laura Frattura;Emanuele Habib;
      Pages: 26 - 34
      Abstract: Buildings with mixed residential and commercial units show relevant power peak that are further increased by shifting from gas-driven systems to an electric source. The proposed solution is to organize a microgrid for such type of buildings, aggregating different users with a common electric distribution system with a single connection to the grid, a local common generation, and a common heating/cooling system (electric driven). This approach upgrades a group of independent small users with rigid loads and chaotic behavior to a large user with a flexible and controlled profile. A central building automation control system managing all built-in technical systems and smart appliances may control the load, minute by minute, shifting in time shiftable and controllable loads, and merging different kinds of loads, obtaining a flatter diagram. The authors consider the suggested approach convenient to realize a demand side management (DSM) for residential/commercial buildings. distribution system operator (DSM) exploits the flexibility of smart appliances and the thermal inertia of the structure, by imposing local and central set points of heating and cooling systems, according to actual global net load and generation at a given moment. In this paper, main aspects of the proposed control system are presented and simulations for a given case study with a local photovoltaic system generation are provided. Results show that this approach may lead to a power peak reduction up to 20% even in the unfavorable case of combining commercial and residential units. Moreover, full self-consumption of locally generated energy from renewable energy systems may be achieved.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • District Heating Technologies: Is it Chance for CHP Plants in Variable and
           Competitive Operation Conditions?
    • Authors: Polina Ivanova;Antans Sauhats;Olegs Linkevics;
      Pages: 35 - 42
      Abstract: District heating system with power generation is integrated in the electricity system since combined heat and power (CHP) plants are used for heat supply. Nowadays, the changes happen in the electricity system and conventional CHP plant operation. They are caused by wide integration of renewable energy sources (RES) in energy production process, feed-in tariffs for RES, the implementation of market mechanisms, and the incremented requirement in energy efficiency and flexibility of power plants. This creates new opportunities and conditions for district heating (DH) and power system cooperation though the use of DH flexible technologies, i.e., power-to-heat (P2H) technologies (electric boilers (EB) and heat pumps). The use of P2H technologies is limited and they are not costs-efficient due to electricity tariff formed components. Two Targets of EB use at power plant are evaluated, omitting these components, to show the usefulness and significant of these technologies for conventional generation.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Development of a Real-Time Web-Based Power Monitoring System for the
           Substation of Petrochemical Facilities
    • Authors: Long Zhao;Igor B. M. Matsuo;Farshid Salehi;Yuhao Zhou;Wei-Jen Lee;
      Pages: 43 - 50
      Abstract: Petrochemical industry not only consumes a large amount of electricity every year but also requires high-quality power supplies. Any unexpected power failure could shut down the entire production line and cause significant financial loss. Meanwhile, due to the large electricity consumption and intensive power demand, in-house cogeneration plants have been equipped for most petrochemical facilities. Thus, any power interruption or disturbance between a petrochemical facility and interconnected power grids could affect both sides of the power systems. Therefore, having high power quality becomes one of the most critical parts for petrochemical facilities. To avoid unexpected power failure and to provide a better understanding of the power system at petrochemical facilities, a fast, precise, and reliable power monitoring system is required. A novel real-time web-based power monitoring system on field-programmable gate array platform is developed in this paper for a power substation at the petrochemical facility. Besides the data collecting with event-triggering mechanism and measurement data recording functions, subsynchronous oscillation detection application is also developed in this system. This monitoring system could provide precise data to help engineers with insightful analysis of the electric system to prevent a power failure, and it also could help system operators to have a better understanding of the system operation characteristics.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Transformer Management System for Energy Control of Customer Demand
           Response and PV Systems
    • Authors: Te-Tien Ku;Chao-Shun Chen;Chia-Hung Lin;Cheng-Ting Hsu;Hui-Jen Chuang;
      Pages: 51 - 59
      Abstract: This paper proposes an innovative transformer management system (TMS) for energy control of customer loads and photovoltaic (PV) systems to solve the problems of transformer overloading and overvoltage due to power injection by PV renewable energy. The operation status of distribution transformers is monitored by transformer terminal unit (TTU) and reported to the control master station via the hybrid communication system. The demand response of customer load control is activated to reduce the loading level of transformers for mitigation of overloading problem. For the residential customers with installation of roof top PV system, the TTU is applied to perform the power factor control of smart inverter to prevent the overvoltage problem. The hybrid communication system consisting of power line carrier, LoRa radio frequency, and optical fiber is used to provide two-way communication for data collection and controls of customer loads and PV system. According to the field testing of the proposed TMS in Taiwan Power Company, the adaptive energy control of customer loads by TTU is executed when the overloading problem of distribution transformer occurs. The TTU also performs the power factor control of PV smart inverters to solve the overvoltage problem due to too much of PV power being injected during the solar peak period. The overvoltage problem due to PV power injection has also been solved by TTU for control of PV smart inverters to perform the proper reactive power compensation.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Improving Grid Integration of Hybrid PV-Storage Systems Through a Suitable
           Energy Management Strategy
    • Authors: Maria Carmela Di Piazza;Massimiliano Luna;Giuseppe La Tona;Annalisa Di Piazza;
      Pages: 60 - 68
      Abstract: This paper proposes a method to reshape the daily grid-injected photovoltaic (PV) power profile while keeping the same energy amount. In particular, an energy management algorithm is used for reducing the peak-to-mean ratio (PMR) of the injected power profile. This method allows for a better integration of hybrid PV-storage systems into the power grid since it helps avoiding or at least reducing the need for curtailment measures aimed at preventing grid instability. Furthermore, it is compatible with negotiation schemes that require transmitting the expected power profile to the grid manager one day ahead. Thus, a better market participation of PV producers can be achieved. Five different scenarios, with varying system parameters, have been simulated over a one-year period, showing a reduction of the PMR up to 64% and a reduction of the power ramp rate up to 48%. These results confirm the effectiveness of the proposed approach.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Battery Energy Storage for Seamless Transitions of Wind Generator in
           Standalone Microgrid
    • Authors: Priyesh J. Chauhan;Bonthapalle Dastagiri Reddy;Saurabh Bhandari;Sanjib Kumar Panda;
      Pages: 69 - 77
      Abstract: This paper presents a control scheme for a standalone microgrid having a nondispatchable fixed-pitch variable-speed wind generator (WG) and a battery energy storage (BES). The WG is directly interfaced at the point of common coupling (PCC) and the BES is interfaced at the PCC via a bidirectional dc-ac converter. The unique aspect of the control strategy is that the BES not only regulates the PCC voltage and frequency by active-reactive power compensations, but also ensures proper synchronization and disconnection of the WG during wind velocity variations. A simple control scheme, with only one interfacing converter and one voltage feedback loop, provides an uninterruptible electrical power supply to critical loads during various operating modes and enables seamless transition of the WG. Performance of the proposed system under all operating modes and transitions is tested through modeling and simulation in MATLAB/Simulink, and validated on laboratory test bench through implementation of the control algorithm on a DSP platform.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Performance Improvement of Grid-Integrated Solar PV System Using DNLMS
           Control Algorithm
    • Authors: Subarni Pradhan;Ikhlaq Hussain;Bhim Singh;Bijaya Ketan Panigrahi;
      Pages: 78 - 91
      Abstract: An integration of renewable sources based distributed generating systems encounters various power quality issues due to uncertain loads at the distribution end. These uncertainties arise due to nonlinearity, disturbances or unbalanced loads. A three-phase grid-integrated solar photovoltaic (PV) system incorporating a control technique based on a modified decorrelation normalized least mean square (DNLMS) algorithm, aiming to enhance its overall performance under adverse conditions, is presented in this work. The three-phase, grid-tied, single-stage solar PV system comprises a solar PV array with a suitable maximum power point tracking method, filters, loads, and a capacitor fed voltage source converter (VSC). The key objective of the solar PV integrated structure with an adaptive law based control algorithm is to attain a unity power factor (UPF) at the grid end ensuring harmonics mitigation from the grid currents. Moreover, this structure effectively transfers active power from the PV array to the local loads and the grid. These aforesaid objectives are achieved through providing controlled switching pulses to the insulated gate bipolar transistor based VSC using the modified DNLMS control algorithm with fast convergence rate. Harmonics-free, sinusoidal reference grid currents, are obtained by using the modified DNLMS algorithm. A simulation model developed in MATLAB/Simulink is used for the validation of the modified DNLMS-based control approach. In the laboratory, an experimental prototype is developed and the proposed algorithm is implemented to verify its performance.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Fault Classification and Voltage Sag Parameter Computation Using Voltage
           Ellipses
    • Authors: Juan Ramón Camarillo-Peñaranda;Gustavo Ramos;
      Pages: 92 - 97
      Abstract: Fault classification and voltage sag parameter computation using voltage ellipses in Clarke's domain are presented in this paper. The voltage sag parameters computed were the point-on-wave of initiation and recovery, residual voltage, and phase-angle jump. A change in the phase reference in Clarke's transformation was proposed to simplify the fault classification procedure. The point-on-wave of initiation and recovery were defined based on the reference circle in Clarke's domain, as described by the system during normal operation. The residual voltage and phase-angle jump were computed using the expressions of α and β components in Clarke's domain and trigonometric theorems. The proposed fault classification and voltage sag characteristics computation were applied to real data provided by the Department of Energy and the Electric Power Research Institute. From the results obtained, it is concluded that the zero-sequence component must be taken in consideration to compute the residual voltage and the phase-angle jump correctly, and to use these results to improve the accuracy of impedance-based fault location methods. The proposed fault classification algorithm is capable of classifying events and computing the residual voltage and phase-angle jump. Additionally, the voltage sag duration of short events and multistage events was successfully computed. This work is an incremental contribution within the field of voltage sag analysis in the time domain using Clarke's transformation.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Grounding the AC Microgrid
    • Authors: Jafar Mohammadi;Firouz Badrkhani Ajaei;Gary Stevens;
      Pages: 98 - 105
      Abstract: Grounding strategy of an ac microgrid affects its line-to-ground fault response, personnel/equipment safety, service continuity, insulation requirements, and protection criteria. Therefore, a comprehensive knowledge of the available grounding strategies and their effects is essential for design and operation of the microgrid components and especially its protection. In this paper, characteristics of different ac distribution system grounding devices and grounding configurations are investigated. Subsequently, ac microgrid grounding requirements and issues are identified based on the unique characteristics and constraints of microgrids. The results of the aforementioned investigations are used to identify the best grounding strategies, i.e., grounding configurations, transformer connection types, and grounding devices, for the ac microgrid. The study results indicate that the four-wire multigrounded configuration is the most suitable choice for the majority of microgrids, especially in North America. The Yg/Δ and Yg/Yg transformers are identified as the most appropriate choices for distributed energy resources (DER) interface to the four-wire multigrounded microgrid. Besides, low-reactance and low-resistance grounding devices are recommended for the DER interface transformers.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • New Generation Tester to Assess the Electrical Safety in Low-Voltage
           Distribution Systems
    • Authors: Massimo Mitolo;Thomas J. Bajzek;
      Pages: 106 - 110
      Abstract: The determination of both magnitude and duration of touch voltages is of paramount importance to protect persons against electric shock hazards, such as those caused by basic insulation failure in equipment/appliances, or direct contact with live parts. The magnitude of touch voltages depends on the impedance of the equipment grounding conductor (EGC) (also referred to as protective conductor), which should be therefore properly sized. In the US, the National Electric Code (NEC) provides minimum sizes for the EGC; however, the NEC further clarifies that the EGC selected in the specific NEC table might need be sized larger to provide adequate electrical safety. In this paper, the authors discuss the major specifications that a “new generation” tester applied to NEC based low-voltage receptacles, or live terminals of feeder/branch circuits, should possess to indicate to users if a ground-fault would cause unsafe touch potentials. Such tester should also unequivocally identify improper wiring of the outlet (e.g., phase-neutral swap, EGC-to-neutral bond).
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • A Novel Method of Frequency Regulation in Microgrid
    • Authors: Upama Bose;Sumit K. Chattopadhyay;Chandan Chakraborty;Bikash Pal;
      Pages: 111 - 121
      Abstract: Owing to generation and demand mismatch, the frequency deviation and the rate of change of frequency (RoCoF) may become drastic at times in an islanded microgrid. This is due to increased penetration of noninertial renewable energy sources that brings down the system's resilience to any kind of disturbance. Therefore, efficient control algorithms are required to mimic the inertial behavior of a conventional synchronous machine to arrest/limit any sudden change. This work focuses on frequency regulation of microgrid during transient conditions by means of fast-responding external energy reserve. The characteristics of a weak grid has been studied and simulated through modeling a virtual synchronous machine. An inverter model is also developed to integrate the energy storage system (ESS) to the grid and a double second-order generalized integrator phase locked loop (DSOGI-PLL) is implemented that is capable of synchronizing the system under distorted and unbalanced situation. A new technique to estimate the frequency of the microgrid is reported. A simple proportional controller-based approach for different level of pulsed power injection (using ultracapacitors and batteries) is proposed and simulated using MATLAB. Experimental demonstration is made using batteries only but with two different current-limits. The controller is implemented using dSPACE1103.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Decoupled Frequency and Voltage Control for Stand-Alone Microgrid With
           High Renewable Penetration
    • Authors: Kwang Woo Joung;Taewan Kim;Jung-Wook Park;
      Pages: 122 - 133
      Abstract: In South Korea, the stand-alone microgrid on an island has synchronous diesel generators and multiple distributed generations (DG) based on renewable energy, and energy storage systems (ESS). According to the active policy of government to develop eco-friendly microgrids with zero carbon emission, many diesel generators in stand-alone microgrids are being replaced by the DGs. It brings challenges on the operation and control of multiple DGs because this causes the lack of inertia, which is originally provided from the diesel generators. This paper proposes a new decoupled frequency and voltage controller for DGs, which is able to keep the grid frequency and voltage magnitude constant. For frequency control, a frequency recovery control loop is newly added to conventional droop and inertia control loops for both effective power sharing and stabilization of frequency response after a disturbance. For voltage control, the proposed controller regulates the grid voltage in an inertia-free mode, in which all diesel generators are disconnected, while providing the conventional reactive power-voltage droop control under a normal condition. Moreover, the adaptive power sharing strategy is newly proposed to avoid the overcharge/discharge conditions of ESSs. As the result, the proposed controller can enhance the resilience and increase the penetration of renewable energies to the stand-alone microgrid. To verify the effectiveness of proposed controller, several case studies are being carried out by using the practical data of a real stand-alone microgrid in South Korea.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Energy Analyzer Emulator for Microgrid Implementation and Demonstration
           and Respective Gateway
    • Authors: Luis Gomes;Pedro Faria;Zita A. Vale;Jorge Silva;
      Pages: 134 - 144
      Abstract: Microgrids have been implemented all over the world in the last years. Several benefits are known for consumers and power grid management. As part of microgrids, the local energy management of renewable energy sources can prevent energy losses and support microgrid operation in islanded modes. Besides the success of the current microgrid implementations, improved components and models are required. This paper proposes two tools that support the implementation of microgrid demonstrations, namely at laboratorial premises. Improved microgrid models implementation enables the development, test, and validation of new energy management methodologies. The first proposed tool is a wireless gateway for energy monitoring and control. To implement complete microgrids, the second tool proposes an energy analyzer emulator, bringing unavailable loads to the microgrid, such as residential loads usually unavailable in R&D centers. A real laboratory microgrid implementation using the proposed gateway and the proposed energy analyzer emulator is presented and discussed, demonstrating the actual capabilities of the developed tools.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Feasibility Study of Superconducting Cable Application to Oil/Gas
           Power Supply Network
    • Authors: Junichi Arai;Kohei Higashikawa;Tadashi Koshizuka;Hisatoshi Ikeda;Noureddine Harid;Ahmed Al-Durra;
      Pages: 145 - 151
      Abstract: In this paper, the static and dynamic behaviors of a power system feeding an oil/gas plant with superconducting (SC) cables are investigated. SC cables have been expected to provide more efficient power supply and less space utilization for power systems compared to conventional cables. On the other hand, their compatibility with the existing power systems has not yet been clarified. In this paper, taking a typical distribution system in an oil/gas plant as an example, we designed high-voltage SC cables and investigated their compatibility with the system from the viewpoint of static and dynamic performances. The voltage distribution under steady-state operation and the transient voltage and current during fault conditions were examined and compared with the case of conventional cables. The results show that, in addition to the efficiency enhancement, SC cables could be applied without any further constraint on circuit breaker duties and insulation coordination requirements.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Third Harmonic Current in a Generator Neutral Earthing Resistor Connected
           to a Large Cable Network
    • Authors: Jason Mayer;Ryan Turner;
      Pages: 152 - 157
      Abstract: A large grid-connected private industrial and residential 11 kV network in northern Australia has its own 11 kV diesel generators to supply essential loads during grid supply outages. The generators each have a neutral earthing resistor (NER). When islanded from the grid, one NER provides the system reference. Significant circulating current was causing overheating of the NER. This paper describes the investigation undertaken, the options considered for rectification and the results from commissioning of the implemented solution.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Special Field Measurement Results of an Onshore Wind Farm Connected to
           Power Grid of Taiwan Power System Subject to Typhoon Matmo
    • Authors: Li Wang;Shun-Chin Ke;Ting-Wei Hong;Chien-Hsiang Yu;Chuan-Chieh Yeh;Wei-Sheng Liu;Bing-Lin Kuan;Xiu-Yu Lu;Hong-Yi Wu;Anton Victorovich Prokhorov;
      Pages: 158 - 166
      Abstract: This paper studies and analyzes the power-quality measurement results due to the special operating characteristics of the wind turbines of a commercial onshore wind farm connected to the power grid of Taiwan Power System when Typhoon Matmo passed through Taiwan. This Kuan-Yuan onshore wind farm of 28.5 MW with 19 1.5-MW wind-turbine generator (WTG) based on doubly fed induction generator is connected to Kuan-Yin primary substation through two of four step-up main transformers of 161/69 kV, 200 MVA. The measured data were recorded from July 22, 2014 to July 29, 2014 for total seven days. During the measurement period, Typhoon Matmo just passed through Taiwan and the 19 WTGs were forced to stop. The power-quality measurement results due to the special operating characteristics of the wind turbines of the studied Kuan-Yuan wind farm subject to Typhoon Matmo were also recorded and studied. According to the measured results, the power quality of the studied Kuan-Yuan onshore wind farm during the measurement period can meet the grid code of Taiwan Power Company except the voltage flicker of ΔV10. The relationships of the recorded times and dates between the measured electrical quantities and power-quality results of the studied onshore wind farm and the Typhoon Matmo passed through Taiwan are also discussed.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • A Life Loss Tool for an Optimal Management in the Operation of Insulated
           LV Power Cables
    • Authors: Giuseppe Parise;Luigi Martirano;Luigi Parise;Luca Gugliermetti;Fabio Nardecchia;
      Pages: 167 - 173
      Abstract: An optimized system management of a commercial and industrial power system must take care of the actual operational and energetic duty of the power system distribution. A procedure based on the Arrhenius model of the thermal aging of insulating materials allows introducing the relative time coefficient and promoting a heuristic method, as a rule of thumb, to estimate the life loss and the residual useful life for insulated power cables. This paper deals with simplified models of low-voltage (LV) cable systems characterized by one and two time constants to evaluate the cable temperature behavior and the influences of the ambient and installation conditions. Furthermore, this paper proposes a device to count the “life loss hours” for LV power cables of main/critical circuits.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Data-Driven Probabilistic Power Flow Analysis for a Distribution System
           With Renewable Energy Sources Using Monte Carlo Simulation
    • Authors: Gonzalo Esteban Constante-Flores;Mahesh S. Illindala;
      Pages: 174 - 181
      Abstract: This paper investigates the effect of uncertainty in the allocation of photovoltaic (PV) generation, solar irradiance, and its impact on the power flow in a distribution network. The solar irradiance available in the National Renewable Energy Laboratory Resource Data Center is clustered into two states: high and low irradiance defined by a threshold. The uncertainty is modeled based on Non-Gaussian distribution, obtained using kernel density estimation. This estimation aids in achieving the probability density function and cumulative distribution functions of the solar irradiance. Moreover, the load demand, wind speed, and generator location are modeled according to Gaussian, Weibull, and discrete uniform distribution functions, respectively. As a part of probabilistic power flow, the backward/forward sweep method is used to solve each scenario of the Monte Carlo simulation. The proposed framework is applied to the 33-node test system considering three different test cases. The first case considers deployment of PV systems in three microgrids of the electric grid, and the other two test cases analyze different levels of penetration of randomly allocated PV and wind power systems. At the end, the results indicate potential reverse power flow through certain branches of the grid, and the renewables have a major impact on the system.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Transient Stability Analysis for Offshore Wind Power Plant Integration
           Planning Studies—Part I: Short-Term Faults
    • Authors: Amirhossein Sajadi;Richard M. Kolacinski;Kara Clark;Kenneth A. Loparo;
      Pages: 182 - 192
      Abstract: Power system planning is the process of forecasting load demand and ensuring sufficient generation and reserve capacities over some planning horizon. This process includes investigation of steady-state and dynamic operations of the power system of interest. This paper addresses the transient stability (also known as large-signal stability) analysis of power systems for offshore wind power plant integration planning studies. In particular, this study develops a comprehensive practical methodology to assess the transient stability of power systems, including rotor angle stability, voltage stability, and frequency response for large scale power systems. This methodology considers variability of the offshore wind power plants as well as the type of any faulted system's components present. Additionally, this methodology is applicable to the study of both short-term and long-term faults, though only short-term faults are considered here (long-term faults are treated sequentially in a companion paper). This paper considers the integration of offshore wind power plants into existing power systems and demonstrates the utility of this methodology through the examination of the specific case of integrating 1000 MW of offshore wind power into the FirstEnergy/PJM service territory using a realistic model of 63k-bus test system that represents the U.S. Eastern Interconnection.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Transient Stability Analysis for Offshore Wind Power Plant Integration
           Planning Studies—Part II: Long-Term Faults
    • Authors: Amirhossein Sajadi;Richard M. Kolacinski;Kara Clark;Kenneth A. Loparo;
      Pages: 193 - 202
      Abstract: This paper addresses the transient stability (also called large-signal stability) analysis of power systems for offshore wind power plant integration planning studies. In particular, this study develops a comprehensive practical methodology to assess the transient stability of power systems, including rotor angle stability, voltage stability, and frequency response for large-scale power systems. This methodology considers variability of the offshore wind power plants as well as the type of any faulted system's components present and is applicable to the study of both short-term and long-term faults. Part I of this research discussed the short-term faults, whereas Part II, the present paper, discusses long-term faults. This research considers the integration of offshore wind power plants into existing power systems and demonstrates the utility of this methodology through the examination of the specific case of integrating 1000 MW of offshore wind power into the FirstEnergy/PJM service territory using a realistic model of 63 k-bus test system that represents the U.S. Eastern Interconnection.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Induction Motor Modeling for Development of a Secure In-Phase Motor Bus
           Transfer Scheme
    • Authors: Normann Fischer;Brian K. Johnson;Andrew G. Miles;Joseph D. Law;
      Pages: 203 - 212
      Abstract: This paper presents techniques to model an induction machine during the transient periods of a motor bus transfer operation and then develops a more secure in-phase motor bus transfer scheme. To increase the robustness of the electrical power supply, two independent power supplies are typically routed to the industrial facilities with large motor loads. The motor loads are split between two buses. If one of the two power supplies becomes unavailable due to a fault on the power line, the supply for the faulted bus is tripped, and the two buses are paralleled to keep the facility fully operational. The machines supplied by the source that experiences the failure start to slow down when the voltage sags, potentially leading to severe transient torques on the motor shafts upon resynchronization, complicating the transfer process. Efficiently and accurately modeling the induction machines allows the creation of transfer schemes that lead to successful in-phase motor bus transfers where the worst-case torque on any of the motor shafts is limited to 6 p.u. This enables the motor to be synchronously connected to an alternative power source in the event of a supply disruption.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Frequency Regulation at a Wind Farm Using Time-Varying Inertia and Droop
           Controls
    • Authors: Yuan-Kang Wu;Wu-Han Yang;Yi-Liang Hu;Phan Quoc Dzung;
      Pages: 213 - 224
      Abstract: As renewable power generation becomes more prevalent, the problem of frequency stability has become a particular concern of transmission system operators, especially those of small power transmission systems. Traditional wind generation systems do not provide frequency regulation because they are decoupled from the power grid. Therefore, as conventional thermal generators are replaced by wind generators, the issue of frequency regulation for wind generation systems has become increasingly important. To release the kinetic energy stored in the rotating mass, inertia and droop control loops can be added into the controller of a wind turbine (WT). This work proposes an advanced control strategy with the time-varying gains of two control loops. In the proposed strategy, the gains are determined based on the desired frequency-response time. Moreover, the initial gain of the control loop is determined based on the wind speed, considering the operating condition of each WT in a wind farm. The effectiveness of the proposed method is verified by using an actual power system, revealing that it can be used to improve frequency regulation in a power grid.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Voltage Control in Low-Voltage Grids Using Distributed Photovoltaic
           Converters and Centralized Devices
    • Authors: Alessandro Ciocia;Valentin A. Boicea;Gianfranco Chicco;Paolo Di Leo;Andrea Mazza;Enrico Pons;Filippo Spertino;Nouredine Hadj-Said;
      Pages: 225 - 237
      Abstract: This paper studies the application of distributed and centralized solutions for voltage control in low voltage (LV) grids with high photovoltaic (PV) penetration. In traditional LV grids, the coordination of distributed PV converters and a centralized device would require massive investments in new communication and control infrastructures. The alternative of exploiting distributed PV converters for voltage control is discussed, showing that it can help to stabilize the voltage in the grid connection points also without coordination between them and/or with a centralized unit. The goal of this paper is to investigate how the setup of the voltage controllers inside PV inverters affects the operation of these controllers taking into account the limits for reactive power injection. In addition, the interaction of distributed PV converters with centralized devices (static var compensators and on load tap changers) is analyzed to assess whether additional benefits may come in these cases.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Mixed-Integer Algorithm for Optimal Dispatch of Integrated PV-Storage
           Systems
    • Authors: Francesco Conte;Fabio D’Agostino;Paola Pongiglione;Matteo Saviozzi;Federico Silvestro;
      Pages: 238 - 247
      Abstract: The exploitation of combined photovoltaic (PV) plants and storage systems is nowadays assuming growing importance, due to the technical, environmental, and economical benefits which can derive from an optimal integration. In this paper, a mixed-integer algorithm for the optimal dispatch of a storage system, based on the day-ahead PV forecasting is developed. The optimization objective is the maximization of the total production of the integrated system, according to a requested active power profile, which can be defined by the operator. The study case of an existing distribution management system, which operates on the low-voltage microgrid at University of Genova is analyzed. The procedure is validated by field results with particular attention to the storage round-trip efficiency.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Assessment of a Decaying DC Offset Detector on CTs Measurements Applying
           Mathematical Morphology
    • Authors: David Celeita;Juan David Perez;Gustavo Ramos;
      Pages: 248 - 255
      Abstract: Power system protections are highly sensitive to decaying dc offset that could appear when a fault occurs. The consequences of this effect represent a challenge in the coordination of protection devices that have been widely studied. The elimination of the dc offset component of current transformers (CTs) measurements is the objective of this paper, including a new autonomous detector based on mathematical morphology. The idea enhances the digital signal processing to prepare the information before the protective device takes a decision. The detection and fast elimination of the decaying dc offset on current signals could improve the speed of protection, coordination, and selectivity. The paper presents the proposed algorithm and assesses the solution using alternative transient program. The model of the CT used for this validation is also presented. Results show the potential of the mathematical morphology for signal processing to delete the dc offset component.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Coordination of Transformer On-Load Tap Changer and PV Smart Inverters for
           Voltage Control of Distribution Feeders
    • Authors: Te-Tien Ku;Chia-Hung Lin;Chao-Shun Chen;Cheng-Ting Hsu;
      Pages: 256 - 264
      Abstract: To enhance the outage quality of a distribution system with a high penetration of photovoltaic (PV) renewable energy, this paper proposes a coordinating control strategy for an on-load tap changer (OLTC) of the main transformer in a distribution substation and PV smart inverters. The voltages at the end points of all distribution feeders that are served by the main transformer and the power generation of each PV system are collected using a SCADA system. The hourly tap position of the OLTC is then derived from the daily profiles of feeder voltage and the injected power that is generated by all PV systems along the feeder. Thereafter, the PV smart inverters perform autonomous control of reactive power compensation so that the voltage at the point of common coupling can be fixed at the specified voltage level. To demonstrate the effectiveness of the proposed voltage-control strategy, a main transformer, which serves six feeders of the Taiwan Power Company(Taipower) with high PV penetration, was considered in a case study. The proposed coordinating control of the OLTC and PV smart inverters dramatically improved the voltage quality of the distribution feeder and enabled the effective mitigation of the impact of large PV integration in the distribution system.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Highly Demagnetization Performance IPMSM Under Hot Environments
    • Authors: Noriyoshi Nishiyama;Hiroki Uemura;Yukio Honda;
      Pages: 265 - 272
      Abstract: This paper examines how changing the magnetic orientation of permanent magnets in concentrated winding interior permanent magnet synchronous motors (IPMSMs) affects their demagnetization resistance. We evaluated a prototype for demagnetization at 180 °C that consists of a 130° V-shaped rotor core in which parallelogram magnets with oblique orientation are arranged and confirmed by finite element analysis where the demagnetization resistance increases as magnetic field orientation angle α becomes larger. For demagnetization evaluation of the prototype, it is easier to change the rotor core shape of a two-pole test rotor of a multipole IPMSM than a multipole rotor, and the demagnetization evaluation is performed using a small number of magnets.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • A Simple Method to Determine Double-Cage Rotor Equivalent Circuit
           Parameters of Induction Motors From No-Load and Locked-Rotor Tests
    • Authors: Shu Yamamoto;Hideaki Hirahara;Akira Tanaka;Takahiro Ara;
      Pages: 273 - 282
      Abstract: This paper presents a simple method to determine double-cage rotor equivalent circuit parameters of induction motors (IMs). A new formula to calculate the double-cage rotor equivalent circuit parameters is proposed. The formula is sufficiently simple to be calculated by a calculator but can determine the parameters of outer- and inner-cage conductors. The proposed method takes the magnetic saturation effect of a closed-slot rotor into account and applies to not only double-cage but also single-cage IMs. All equivalent circuit parameters can be determined using only classical no-load and locked-rotor tests. Thus, the proposed method is suitable to be used as a standardized testing method for IMs. The validity of the proposed method is demonstrated by experimental results on four 5.5 kW-200 V-4 P-22 A-50 Hz IMs: double- and single-cage IMs with semi-closed- and closed-slot rotors.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Copper Loss Analysis of a Multiwinding High-Frequency Transformer for a
           Magnetically-Coupled Residential Microgrid
    • Authors: Mohammad Jafari;Zahra Malekjamshidi;Jianguo Zhu;
      Pages: 283 - 297
      Abstract: Improvements in characteristics of magnetic materials and switching devices have provided the feasibility of replacing the electrical buses with high-frequency magnetic links in small-scale microgrids. This can effectively reduce the number of voltage conversion stages, size, and cost of the microgrid, and isolate the sources and loads. To optimally design the magnetic link, an accurate evaluation of copper loss of the windings considering both the current waveforms and parasitic effects are required. This paper studies the copper loss analysis of a three-winding high-frequency magnetic link for residential microgrid applications. Due to the nonsinusoidal nature of the voltages and currents, the loss analysis is carried out on a harmonic basis taking into account the variations of phase shift, duty ratio, and amplitude of the waveforms. The high-frequency parasitic phenomena including the skin and proximity effects are taken into account. The maximum and minimum copper loss operating conditions of the magnetic link and their dependency on the phase shift angle and the duty ratio of the connected waveforms are studied. A prototype of the microgrid including the magnetic link is developed to validate the theoretical analysis, evaluate the microgrid efficiency, and perform the loss breakdown.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • A Permanent Magnet Assist, Segmented Rotor, Switched Reluctance Drive for
           Fault Tolerant Aerospace Applications
    • Authors: Sana Ullah;Steve P. McDonald;Richard Martin;Maamar Benarous;Glynn J. Atkinson;
      Pages: 298 - 305
      Abstract: This paper presents the design, analysis, prototype, and testing of a new fault tolerant electrical drive topology. The segmented rotor switched reluctance machine (S-SRM) has been modified to include permanent magnet assist by placing magnets in the stator slot opening. This introduces a magnetic bias which extends the magnetic operating region of the machine and results in greater torque when compared to the conventional fault tolerant segmental rotor switched reluctance machine. This new torque dense, fault tolerant topology was investigated using 2-D (twodimensional) and 3-DFE methods and a prototype machine built, tested and verified against the simulations. Experimental testing was carried out with and without the magnets to assess the effect of the PM assist on torque performance. Static tests were carried out to obtain the torque-flux linkage-angle waveforms and then this information used to tune a bespoke drive and test the system under dynamic conditions. The superior fault tolerant performance of this PMA S-SRM topology is highlighted by measurements taken under phase open and short circuit fault conditions. The tests show that this fault-tolerant topology not only meets the mass requirements of the aerospace application, set originally by a PMSM, but also, with the magnets now placed on the stator the rotational induced EMFs and associated short circuit currents during a fault are drastically reduced. Hence the fault tolerance of this topology is an improvement on the PMSM topology, and it will be of benefit to fault critical systems such as aerospace drives and actuators.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Reduction of Inverter Carrier Harmonic Losses in Interior Permanent Magnet
           Synchronous Motors by Optimizing Rotor and Stator Shapes
    • Authors: Katsumi Yamazaki;Yusuke Togashi;Takeshi Ikemi;Shunji Ohki;Ryoichi Mizokami;
      Pages: 306 - 315
      Abstract: In this paper, we investigate rotor and stator designs of interior permanent synchronous motors for variable speed/load applications to reduce the carrier harmonic losses caused by pulsewidth modulated inverters. The rotor core and magnet shapes are determined by automatic optimization methods with electromagnetic field analysis, which considers the inverter carrier. Appropriate stator-winding configurations are also investigated by this analysis. It is clarified that the total carrier harmonic loss can be reduced by more than 20% by optimizing both the stator and rotor shapes, whereas the other important characteristics are not deteriorated. The mechanism of carrier loss reduction is also clarified.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Contribution to the System Design of Contactless Energy Transfer Systems
    • Authors: David Maier;Jörg Heinrich;Marco Zimmer;Marcel Maier;Nejila Parspour;
      Pages: 316 - 326
      Abstract: In this contribution, a design procedure that is applicable to many kinds of wireless or contactless energy transfer systems is proposed. The design procedure is limited to near field wireless energy transfer systems in resonant operation. For this purpose, the input impedance and voltage transfer function of different natural frequencies are calculated analytically, and moreover, the behavior of the system is described. Following three issues lead to a readily applicable design procedure. First, the knowledge of the transfer functions. Secondly, the knowledge of basic magnetic properties and lastly, the known influence of harmonics according to rectifier and inverter. This design procedure is demonstrated with two hardware setups.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Implementation of a YBCO Superconducting ZFC-Magnetic Bearing Prototype
    • Authors: António J. Arsénio;Miguel L. Roque;Martim V. Carvalho;Carlos Cardeira;Rui Melicio;Paulo J. Costa Branco;
      Pages: 327 - 335
      Abstract: This paper presents the conception and real prototype implementation of an original superconducting frictionless zero field cooling (ZFC) bearing. In the previous paper, a viability study of a ZFC-superconducting bearing concept was conducted. It showed that the virtual prototype was feasible. Moreover, the simulation studies showed that a ZFC superconducting track provides not only effective lateral stability but also higher levitation forces than the commonly used field cooling (FC) tracks. In this paper, the new ZFC bearing virtual prototype is modeled in three-dimensional and physically realized. The implementation was made in high-density polyurethane, for low-temperature robustness, using both a three axes computer numerical control (CNC) milling machine and an additive manufacturing technique. Results show the effectiveness of the real bearing. Static analysis was done and dynamic analysis was also introduced.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Analysis of Damper Transient Currents in Salient-Pole Synchronous
           Generator With Skewed Armature Slots Considering Interbar Currents
    • Authors: Yang Zhan;Kangkang Kong;Guorui Xu;Jinping Kang;Haisen Zhao;
      Pages: 336 - 343
      Abstract: Salient-pole synchronous generators with skewed armature slots have damper interbar currents that flow transversely between the damper bars through the core. The pattern of interbar and damper bar currents under disturbances is useful information to designers for comprehensive knowledge of damper's electromagnetic performances and potential improvement of design. This paper presents the measurement of the interbar and interpole resistances and develops the multislice two-dimensional (2-D) finite-element model with integrated interbar circuit for a 10-kW model generator. The damper currents of the generator under 3-phase sudden short circuit are calculated with this model and compared with the measured results for validation. The influences of the variation in skew and bar-iron contact resistance on the pattern of interbar and damper bar transient currents are investigated by calculations for the fault of 3-phase sudden short circuit. The calculated results show that small bar-iron contact resistances may result in axially uneven distribution of damper bar transient currents, and the magnitude of slot ripple in the interbar current at different axial positions vary with the skew in different manners.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Impact of Machine Magnetization State on Permanent Magnet Losses in
           Permanent Magnet Synchronous Machines
    • Authors: Daniel Fernández;María Martínez;David Reigosa;Juan M. Guerrero;Carlos Manuel Suárez Alvarez;Fernando Briz;
      Pages: 344 - 353
      Abstract: Negative d-axis current injection used in interior permanent magnet synchronous machines (PMSMs) weakens the permanent magnets' (PMs) flux, eventually increasing the PMs losses and reduces, therefore, the machine efficiency. Several studies have reported that the increase in the air gap flux harmonic content as the primary reason for the PM losses increase in flux weakening operation, disregarding PM properties variation with the magnetization state (MS) due to PM magnetoresistive effect. This paper analyzes the variation of PM losses with the MS and flux weakening current, the target being threefold: a better understanding of PM losses production mechanisms; to analyze the impact of MS on the thermal behavior of the machine; use this knowledge to improve the machine design.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Influence of Adjacent Teeth Magnet Polarities on the Performance of Flux
           Reversal Permanent Magnet Machine
    • Authors: Huayang Li;Z. Q. Zhu;
      Pages: 354 - 365
      Abstract: This paper provides a comprehensive analysis of performance difference among various kinds of flux reversal permanent magnet (FRPM) machines having different permanent magnet (PM) arrangements. Four PM arrangement types are, first, identified by the number and relative polarities of PMs on the stator teeth, and their influence on the equivalent pole-pair number of the armature winding and working harmonics of the air-gap field is revealed. Then, the torque variation against the rotor pole number of each PM arrangement is analyzed. The electromagnetic performance of four PM arrangements with a 14-pole rotor is compared in detail. It shows that the FRPM machine, in which four PM pieces are mounted on each stator tooth and two adjacent magnets on different stator teeth are of opposite polarities, offers the highest torque density and the highest efficiency, which make it promising in low-speed high-torque applications. In addition, four prototype machines are manufactured and tested to validate the findings.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • The Degradation Depth of Non-grain Oriented Electrical Steel Sheets of
           Electric Machines Due to Mechanical and Laser Cutting: A State-of-the-Art
           Review
    • Authors: Madeleine Bali;Annette Muetze;
      Pages: 366 - 375
      Abstract: Literature agrees that cutting may damage the electromagnetic properties of electrical steel sheets, notably along the cut edge. However, statements on the depth of the deterioration vary. An analysis of the various results presented would allow for a better consideration of the material degradation in the modeling of electromagnetic properties of the cut steel sheet in electric machines. To this aim, this paper analyzes and summarizes the deterioration depths presented in the literature. It not only provides an overview of the quantitative results, but discusses these in the context of the respective measurement method, since every technique used only provides an image of some of the aspects of the cut material affected by the cutting process.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Electrical Propulsion System Design of Chevrolet Bolt Battery Electric
           Vehicle
    • Authors: Faizul Momen;Khwaja Rahman;Yochan Son;
      Pages: 376 - 384
      Abstract: The propulsion system design of General Motors' Chevrolet Bolt battery electric vehicle (BEV) incorporates the use of a permanent magnet synchronous motor. Magnets are buried inside the rotor in double layer “V” arrangement and the rotor design optimizes the magnet placement between the adjacent poles asymmetrically to lower torque ripple and radial force. Rotor design also optimizes the placement of a pair of small slots stamped near the rotor outer surface at different locations in adjacent poles to provide further reduction in torque ripple and radial force. As a result of all these design features, the Chevrolet Bolt BEV electric motor is able to meet the GM stringent noise and vibration requirements without implementing rotor skew, which is known to lower the motor performance and add complexity to the rotor manufacturing. Similar to Chevrolet Spark BEV, a bar-wound stator construction known to provide high slot fill, shorter end-turn length, and other benefits is implemented in Chevrolet Bolt BEV. To lower the winding ac effect at higher speeds, the Chevrolet Bolt BEV motor implements six conductors per slot design while four conductors per slot design was used in the Chevrolet Spark motor design. As a result, individual conductor size is smaller in new design resulting in reduced winding ac effects and improved joule loss at high-speed operations. Chevrolet Bolt BEV stator design also adopts a special feature, introduced in Gen2 (2nd generation) Chevrolet Volt; the size and placement of stator slot openings under each pole are optimized to lower torque ripple and radial force. This feature acts as a supplement to the torque ripple and radial force reduction features introduced in the rotor design as described above.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Cogging Torque Minimization in Transverse Flux Machines
    • Authors: Tausif Husain;Iftekhar Hasan;Yilmaz Sozer;Iqbal Husain;Eduard Muljadi;
      Pages: 385 - 397
      Abstract: This paper presents the design considerations in cogging torque minimization in two types of transverse flux machines. The machines have a double stator-single rotor configuration with flux concentrating ferrite magnets. One of the machines has pole windings across each leg of an E-Core stator. Another machine has quasi-U-shaped stator cores and a ring winding. The flux in the stator back iron is transverse in both machines. Different methods of cogging torque minimization are investigated. Key methods of cogging torque minimization are identified and used as design variables for optimization using a design of experiments (DOEs) based on the Taguchi method. A multilevel DOE is proposed as an optimization method to reach an optimum solution with minimum simulations. The case study is analyzed in a two-level DOE optimization. Finite element analysis (FEA) is used to study the different effects. Two prototypes are fabricated for validating the FEA results.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Standard Efficiency Determination of Induction Motors With a PWM Inverter
           Source
    • Authors: Emmanuel B. Agamloh;Andrea Cavagnino;Silvio Vaschetto;
      Pages: 398 - 406
      Abstract: Induction motor loss segregation and efficiency measurement requires loading dynamometers and other equipment, such as a variable voltage sinusoidal power supply. These are expensive and not often available even when a loading device is accessible. Variable frequency drives are now widely used for operating induction machines and are more widely available and less expensive. However, their use in place of a fixed frequency sinusoidal power supply to directly measure machine efficiency is intriguing, but inherently challenging due to the pulsewidth modulation (PWM) output voltage. This paper presents some investigations for using variable frequency drives to perform IEEE 112B and IEC 60034-2-1 tests. The use of the drive, the measurement criteria, and procedures are reported and discussed. The results presented demonstrate the feasibility of the proposed concept for measuring machine efficiency with a PWM power source.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Contribution to Offline Measurements of PMSM and SyRM Inductances
    • Authors: Andrea Cavagnino;Gianmario Pellegrino;Silvio Vaschetto;Emmanuel B. Agamloh;
      Pages: 407 - 416
      Abstract: The measurement of synchronous inductances for three-phase permanent-magnet (PM) machines is usually performed by means of offline tests connecting the stator windings in different single-phase configurations. A test campaign conducted on different machines has demonstrated that the inductance measurement depends on both the stator winding connection scheme and the rotor position. As a result, a new perspective is provided on the generally adopted methodology for offline measurements of synchronous inductances. In particular, this paper highlights the influence of the connection schemes on the inductance values, using several surface-mounted PM-synchronous and synchronous-reluctance machine examples. This study covers both machines equipped with distributed windings and fractional-slot-concentrated windings.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Current Control Strategy for Dynamic Winding Reconfiguration of Slotless
           Brushless DC Motors
    • Authors: Florian Copt;Douglas Martins Araujo;Christian Koechli;Yves Perriard;
      Pages: 417 - 425
      Abstract: Depending on the winding configuration, the intrinsic characteristic of a motor differs. By reconfiguring the winding, it becomes possible to increase the torque-speed limitation of a motor. Current proposed methodologies for dynamically reconfiguring the winding suffer from important torque jolts during the reconfiguring process if the inductance of the motor is low. In order to guarantee a constant torque, the transient behavior is investigated when the winding is reconfigured from series to parallel or from star to delta configuration. A novel approach combining a fine control of the current amplitude and the commutation angle is presented. Numerical simulations attest to the exactness of the approach and experimental results substantiate the simulated model.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Fault-Tolerant Control of a Low-Speed Six-Phase Induction Generator for
           Wind Turbines
    • Authors: Alin Pantea;Amine Yazidi;Franck Betin;Sébastien Carrière;Arnaud Sivert;Bruno Vacossin;Humberto Henao;Gérard-André Capolino;
      Pages: 426 - 436
      Abstract: In this paper, a fault-tolerant control scheme for a low-speed squirrel cage six-phase induction generator (SC6PIG) connected to a full-scale back-to-back converter structure is proposed and tested on an experimental 24-kW wind turbine test bed that represents a 1/100 of the electrical power of a grid-connected real wind turbine multiphase generator (2.5 MW). The aim of this paper is to define a suitable control algorithm that allows the electrical generation despite the loss of one to three phases on the generator or converter sides. Furthermore, the pole number of the generator is increased to simplify or eliminate the gearbox in such a way as to reduce mechanical sensitivity. Indeed, by multiplying the phase and pole numbers, the robustness against mechanical and electrical faults is improved compared to that of a classic three-phase generator associated with a gearbox. Simulation and experimental tests carried out on a 24kW-230V-24-pole SC6PIG in healthy and faulty mode (one phase missing) assess the feasibility and capacity of the proposed strategy.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Mathematical Modeling of Semicircular Linear Motor Based on Vector
           Potential With Landen's Transformation
    • Authors: Hiroshi Asai;Tomoyuki Shimono;Yasutaka Fujimoto;Takahiro Mizoguchi;Kouhei Ohnishi;
      Pages: 437 - 447
      Abstract: A semicircular linear motor that realizes a motion along circumference of the circle has been developed. To settle the optimal design of this motor by mathematical analysis, the theoretical equation of motor performance has to be clarified. In this paper, the mathematical modeling of semicircular linear motor is carried out from the viewpoint of Lorentz force and magnetic flux density derived by vector potential. By comparing calculated, analyzed, and measured magnetic flux density and thrust force, the validity of derived mathematical model is confirmed. In addition, the cause of difference among three results is also discussed.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Rotor Design and Eddy-Current Loss Suppression for High-Speed Machines
           With a Solid-PM Rotor
    • Authors: Haiyang Fang;Dawei Li;Ronghai Qu;Jian Li;Cong Wang;Bao Song;
      Pages: 448 - 457
      Abstract: High-speed permanent-magnet (PM) machines are promising for many industrial applications. The main design challenge of high-speed PM machines comes from the PM rotor design due to the low strength and high thermal sensitivity of PM materials. In this paper, the mechanical constraints and speed limits for a high-speed rotor topology are derived with analytical equations. Thereafter, a case study is done to design an 80 kW, 80 000 r/min PM machine. Analysis results show that the high rotor eddy-current loss is one of the key factors contributing to the overheat of the PMs. Hence, a hybrid sleeve topology, which contains an inner titanium cylinder and an outer cylinder made up of carbon fiber composite, is proposed to suppress the rotor eddy-current losses. The optimal dimensions of the hybrid sleeve are obtained by finite element analysis. Thereafter, a comparison among the proposed and two other sleeve topologies, namely, the copper clad sleeve and grooved sleeve, is done from the point of view of their rotor eddy-current losses, rotor temperature rise, mechanical stress, and critical speed. The results indicate that the hybrid sleeve gains an advantage over the other two topologies. For the designed case, the rotor eddy-current losses and temperature rise are decreased by 66.4% and 73 °C, respectively, by using the hybrid sleeve. Furthermore, a reduction of 14.5% for the rotor maximum stress is obtained with the hybrid sleeve, while the rotor's first critical speed has little reduction.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Analysis on Position Estimation Error in Position-Sensorless Operation of
           IPMSM Using Pulsating Square Wave Signal Injection
    • Authors: Chae-Eun Hwang;Younggi Lee;Seung-Ki Sul;
      Pages: 458 - 470
      Abstract: In this paper, the theoretical analysis of the position estimation error in position-sensorless operation using pulsating square wave signal injection is presented. The purpose of this paper is to analyze the phenomenon that the position estimation performance varies depending on the injection frequency. Mathematical derivation supported by simulation and experimental results shows that, in no-load condition, the voltage distortion induces position estimation error with 3rd-order harmonics if the frequency of the injected square wave is the same to the switching frequency. While, if the frequency is a half of the switching frequency or heavier load condition in either injection frequency, the effect of nonideal characteristics of inverter disappears and there is no 3rd harmonics in the position estimation error. Therefore, only the effect of cross-coupling inductance is reflected in the estimation error. As the result, the position estimation error appears in the form of 6th-order harmonics due to the spatial harmonics of inductances, and the error is relatively small compared with the switching frequency injection case. The theoretical analysis was verified by simulation and experimental results.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Design and Implementation of Position Sensorless Starting Control in
           Industrial Drives With Output Filter and Transformer for Oil/Pump
           Applications
    • Authors: Jingbo Liu;Jingya Dai;Semyon Royak;Peter B. Schmidt;Ehsan Al-Nabi;Thomas A. Nondahl;
      Pages: 471 - 479
      Abstract: An open velocity loop current regulated sensorless control scheme for both induction and permanent magnetic motor drives with an output sine wave filter and transformer is designed and implemented in this paper. The proposed control scheme provides a low-voltage drive solution for driving medium-voltage motors without substantially oversizing the inverter. Sufficient starting torque is guaranteed with controlled drive and motor current. Laboratory proof-of-concept tests and experimental results on an actual deep well have validated the effectiveness of the proposed control scheme.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Direct Position Control for Ultrahigh-Speed Switched-Reluctance Machines
           Based on Low-Cost Nonintrusive Reflective Sensors
    • Authors: Cheng Gong;Sufei Li;Thomas Habetler;Jose Restrepo;Brian Soderholm;
      Pages: 480 - 489
      Abstract: High-speed switched-reluctance machines (SRMs) are gaining popularity in both academia and industrial communities. One of the reasons that limit the maximum speed of SRMs is the speed limit of commercial rotary encoders due to mechanical considerations. In this paper, a novel direct position control for ultrahigh-speed SRMs is proposed based on nonintrusive reflective sensors. It uses reflective optical sensors to detect the relative position between the rotor and the stator so as to control the on and off states of the switches directly through the analog output trigger signals generated by the optical sensors. In order to generate the maximum output torque, the switching-on and switching-off angles are optimized based on the equivalent Simulink model with the torque- and flux-linkage characteristics obtained from a corresponding finite-element analysis of a high-speed SRM. Finally, the proposed method is validated by experiments with a 500-W 4/2 SRM running up to 100 000 r/min. The proposed control system has many advantages such as low cost and virtually no speed limit, which makes it suitable for ultrahigh-speed applications.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Robust Control for High Performance Induction Motor Drives Based on
           Partial State-Feedback Linearization
    • Authors: Angelo Accetta;Francesco Alonge;Maurizio Cirrincione;Filippo D’Ippolito;Marcello Pucci;Roberto Rabbeni;Antonino Sferlazza;
      Pages: 490 - 503
      Abstract: This paper deals with a robust input-output feedback linearization control technique for induction motors. Indeed, classic feedback linearization presents two main disadvantages: 1) the accuracy of the dynamic model; and 2) the corresponding correct knowledge of the model parameters. To address this issue, the linear controller has been substituted with a suitably controller designed to be robust to the variations of the main parameters of the induction motor, like stator and rotor resistances, and the three-phase magnetizing inductance. The proposed controller has been tested both in numerical simulation and experimentally on a suitably designed test setup. Moreover, it has been compared with the classical feedback linearization based on linear controllers, highlighting the improvements in terms of dynamic performance, when parameter variations occur. Results confirm a significant increase of the robustness of the controller against parameter variations.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • On-Line Stator Resistance and Permanent Magnet Flux Linkage Identification
           on Open-End Winding PMSM Drives
    • Authors: Mario Pulvirenti;Giuseppe Scarcella;Giacomo Scelba;Antonio Testa;M. Mark Harbaugh;
      Pages: 504 - 515
      Abstract: This paper deals with the development and implementation of an on-line technique for the identification of the stator resistance and permanent magnet flux linkage on three-phase, open-end winding, permanent magnet synchronous motor (PMSM) drives. The stator resistance and permanent magnet flux linkage are independently determined by exploiting a special current vector control strategy, which holds one of the phase currents at zero while suitably modifying the other two in order to keep the magnetomotive force unchanged. As will be demonstrated, no additional sensors or special tests are required by the proposed technique; moreover, motor electrical parameters can be on-line estimated in a wide operating range, avoiding any detrimental impact on the torque capability of the PMSM drive. Finally, the electrical machine thermal status can be also estimated from obtained values of the stator resistance and permanent magnet flux linkage.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • A Generalized Discontinuous PWM Scheme for Three-Level NPC Traction
           Inverter With Minimum Switching Loss for Electric Vehicles
    • Authors: Sarbani Mukherjee;Santu Kumar Giri;Sourabh Kundu;Subrata Banerjee;
      Pages: 516 - 528
      Abstract: A discontinuous pulsewidth modulation (DPWM) strategy for three-level neutral-point-clamped (NPC) traction inverter drive for electric vehicles (EVs) with minimum switching loss for the full power factor (PF) range is developed and presented in this paper. Considering the dynamic loading conditions in an EV propelled by an induction motor (IM), the discontinuous modulation strategy is generalized to obtain minimum switching loss for a wide variations in load PF and modulation depth. The dynamic operating conditions in EV may render frequent unbalances in dc-link capacitor voltages in NPC inverter. It is demonstrated that the addition of an appropriate offset signal with the reference discontinuous signals generates compensating neutral current in the right direction, which can be used to mitigate existing unbalance in two dc-link capacitor voltages. Minimum switching loss at variable PF is attained by positioning the nonswitching clamped regions of the reference auxiliary signals according to the load PF. The effectiveness of the proposed scheme for a wide range of torque/speed variations is studied through simulation by developing a MATLAB/SIMULINK model of an IM traction inverter drive with field-oriented control strategy for closed loop control. Finally, the modulation scheme is validated through experimentation in a small-scale prototype NPC inverter with motor loads.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Discrete-Time Voltage Controller for Voltage Source Converters With LC
           Filter Based on State-Space Models
    • Authors: Hyeon-Sik Kim;Hyun-Sam Jung;Seung-Ki Sul;
      Pages: 529 - 540
      Abstract: State-space control could provide both high dynamic performance and sufficient stability margin to voltage source converters with LC filter. However, an inherent digital delay induced by a digital control system deteriorates performance and even induces instability. In this paper, a discrete-time voltage controller is proposed based on a discrete state-space model. First, a state feedback control with a reference feedforward path is designed in the discrete-time domain with consideration for the digital delay. Second, an output current decoupling path is augmented to minimize the effects of an output current disturbance. Controller gains are derived as the functions of system parameters and design specifications, which is based on a direct pole placement and pole-zero cancellation method in a rotating reference frame. Moreover, a parameter sensitivity and digital implementation are discussed to improve the performance and stability of the proposed controller. The effectiveness of the proposed controller is verified with various experimental results. It shows that a filter resonance is well damped out while maintaining wide voltage control bandwidth.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Analysis, Design, and Implementation of a Wireless Power and Data
           Transmission System Using Capacitive Coupling and Double-Sided LCC
           Compensation Topology
    • Authors: Yousu Yao;Yijie Wang;Xiaosheng Liu;Haisong Cheng;Mengyu Liu;Dianguo Xu;
      Pages: 541 - 551
      Abstract: Wireless power and data transmission (WPDT) is required in many scenarios. This paper proposes a novel WPDT scheme based on capacitive coupling. The power transfer is analyzed, and the power circuit is equivalent to a double-sided LCC compensated wireless power transfer system. The modulation, injection, extraction, and demodulation circuits for data transfer are introduced. The function of each element in the proposed system is explained in detail. In order to facilitate the design of a practical WPDT system, the specific steps are summarized. Theoretical analysis on the interferences between the power transfer and data transfer indicates that the interferences can be significantly diminished by proper design. A 100-W WPDT prototype is built. The measured power transfer efficiency, from dc input to dc output, is 90.5%. The transferred data are correctly recovered in the receiver side at a data rate of 119 kb/s. The data circuit works well even though the coupling coefficient is decreased by 60.2%. The practically measured interferences between the power transfer and data transfer are quite small. The power transfer and data transfer are not affected by these interferences.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Investigation of a New Modular Multilevel Converter With DC Fault Blocking
           Capability
    • Authors: Xing Hu;Jianzhong Zhang;Shuai Xu;Yongjiang Jiang;
      Pages: 552 - 562
      Abstract: Modular multilevel converter (MMC) has been a promising candidate in high voltage direct current (HVdc) transmission systems. Due to the features of simple structure, low cost, and low power losses, half-bridge (HB) is usually adopted as the submodule circuit in the traditional MMC. However, an HB submodule circuit-based MMC does not have the capability of blocking dc short-circuit fault, which obstructs the development of low-cost HVdc systems with overhead lines. In order to solve this problem, an MMC with active clamped T-type submodule (ACTSM) to own dc fault blocking capability is proposed in this paper. Compared with other submodule circuits, the proposed ACTSM has many features, such as symmetrical blocking capability, low power losses, low voltage stress, and low amount of independent drive signals. The topology, operation principle, dc fault blocking capability, and distribution of power losses of the ACTSM are presented in this paper. The effectiveness of the ACTSM-based MMC is validated by both simulations and experiments.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Small-Signal Stability Assessment and Active Stabilization of a
           Bidirectional Battery Charger
    • Authors: Vishnu Mahadeva Iyer;Srinivas Gulur;Subhashish Bhattacharya;
      Pages: 563 - 574
      Abstract: A two-stage electric vehicle (EV) battery charger typically consists of an ac-dc converter cascaded with a dc-dc converter. In such a cascaded system, maintaining stability at the intermediate dc link is imperative for reliable operation of the battery charger under different operating modes. This paper addresses the intermediate dc-link stability challenges that exist in a bidirectional two-stage grid connected single-phase battery charger. It is delineated that the small-signal load-dependent resistance of the ac-dc converter plays a crucial role in determining the stability of the bidirectional battery charger. A virtual-resistor-based active damping control strategy that does not require any additional sensors is explored for the ac-dc converter to stabilize the cascaded system under all operating modes irrespective of the power flow direction. Experimental results on a grid-connected single-phase battery charger hardware prototype are presented to validate the proposed models and showcase the improvement in the dc-link stability due to the virtual-resistance-based active damping approach.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Characterization and Performance Evaluation of the State-of-the-Art 3.3 kV
           30 A Full-SiC MOSFETs
    • Authors: Alinaghi Marzoughi;Rolando Burgos;Dushan Boroyevich;
      Pages: 575 - 583
      Abstract: With their intrinsic superiorities such as high breakdown electric field and high thermal conductivity, the silicon carbide (SiC) mosfets are replacing traditional Si insulated gate bipolar transistor (IGBTs) in power electronics applications. However, at higher voltages, SiC mosfets are at early stages of development and are not commercialized yet. This paper presents thorough static and dynamic performance characterization of 3.3 kV and 30 A discrete full-SiC mosfets. The devices under test are noncommercialized samples from Sumitomo Electric Industries, Japan. A complete static characterization is performed on the devices under test from 25 up to 150 °C to reveal their characteristics and their dependency on temperature. Also, for dynamic tests, a double-pulse tester with a high-performance gate driver circuit is designed, and tests are performed at 25, 100, and 150 °C. Key characteristics such as on-resistance and switching losses are compared to those of a Si IGBT with similar voltage and current rating in order to assess advantages of SiC mosfets over existing Si semiconductors. Following static and dynamic characterizations, the performance of the devices is evaluated in a boost converter topology, and the results are compared to that of Si IGBTs. The evaluation results reveal significant superiority for SiC mosfets in terms of efficiency, maximum possible switching frequency, and system power density.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Design of LCL Filter for Grid-Interfaced PV System Based
           on Cost Minimization
    • Authors: C. Poongothai;Krishna Vasudevan;
      Pages: 584 - 592
      Abstract: Many research works report the use of LCL filters for grid-interfaced PV systems. Indiscreet selection of passive LCL filter parameters may result in poor filtering and increased power losses. LCL filter parameter selection is critical to get a good performance and at the same time ensure that losses and costs stay low. This paper proposes a novel approach to design the LCL filter for a grid-interfaced PV system. A cost-based minimization approach on a cost per joule basis for each of the filter elements is explored to obtain the optimal filter design. Simulation results for a 10-kVA grid-connected inverter with an LCL filter are presented in order to verify the efficacy of the proposed design. The impact of designed filter parameters on the ripple current is also discussed in this paper. The total inductance of the LCL filter is varied and filter parameter values which give lowest cost is identified while meeting harmonic standard requirements and the fundamental voltage drop across the filter. Finally, the proposed design is also experimentally validated via a hardware prototype. Results validate the design method in terms of the harmonic attenuation and total harmonic distortion.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Experiment-Based Methodology of Kinetic Battery Modeling for Energy
           Storage
    • Authors: Zeïnabou Nouhou Bako;Mahamadou Abdou Tankari;Gilles Lefebvre;Amadou Seidou Maiga;
      Pages: 593 - 599
      Abstract: This paper presents a methodology of the battery modeling based on experimental tests results. As a main contribution, authors conducted an analysis of the main constraints and effects of each parameter of the batteries model on its behavior and lifetime. This can help to improve the accuracy of the model. Due to its capability to model the recovery effect and the rate-capacity one, the kinetic battery model serves as the basis of the study. Results of experimental tests are used to realize the analysis and to define the suitable methodology of batteries parameters identification. These last can serve for prediction and estimation of the battery lifetime according to the actual operating conditions, particularly in microgrid and distributed systems.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Real-Time Aging Detection of SiC MOSFETs
    • Authors: Feyzullah Erturk;Enes Ugur;John Olson;Bilal Akin;
      Pages: 600 - 609
      Abstract: This paper presents a comprehensive study on degradation monitoring of silicon carbide mosfets and proposes an early warning method to detect aging. The proposed plug-in tool can be integrated to smart gate drivers or directly to power converters. During the accelerated aging tests (power cycling within safe operating area), several electrical parameters are monitored to find out critical signatures and precursors of failure. Among those, gate leakage current is identified as the most practical precursor, which exhibits consistent changes in all aged devices and is relatively easy to monitor. Due to its simple scheme and low cost, it can potentially be embedded into commercial gate drivers featuring improved reliability options.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Prevention of Oscillatory False Triggering of GaN-FETs by Balancing
           Gate-Drain Capacitance and Common-Source Inductance
    • Authors: Kazuhiro Umetani;Ryunosuke Matsumoto;Eiji Hiraki;
      Pages: 610 - 619
      Abstract: Gallium-nitride-field-effect transistors (GaN-FETs) are promising switching devices with fast switching capability. However, they commonly have low gate threshold voltage, suffering from susceptibility to the false triggering. Particularly, the oscillatory false triggering, i.e., a self-sustaining repetitive false triggering, can occur after a fast switching, which is a severe obstacle for industrial applications. The purpose of this paper is to elucidate the design instruction for preventing this phenomenon. The oscillatory false triggering is known to be caused by the parasitic oscillator circuit formed of a GaN-FET, its parasitic capacitance and the parasitic inductance of the wiring. This paper analyzed the nonoscillatory condition of this oscillator. The result revealed an appropriate ratio between the gate-drain capacitance and the common-source inductance is a key to prevent the oscillatory false triggering. Experiment successfully verified this analysis result, supporting the effectiveness of the appropriate design of this ratio for preventing the oscillatory false triggering.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Distributed Voltage Equalization Design for Supercapacitors Using State
           Observer
    • Authors: Weirong Liu;Yu Song;Hongtao Liao;Heng Li;Xiaoyong Zhang;Yun Jiao;Jun Peng;Zhiwu Huang;
      Pages: 620 - 630
      Abstract: The switched shunting resistor circuit is a classical and practical passive equalization scheme that nevertheless suffers from the voltage imbalance after the charging process. It results from the discrepancy of the shunting resistor and the physical characteristics of supercapacitor (SC) cells. In this paper, the distributed voltage equalization control strategies with the proportional-integral (PI) observer for the switched shunting resistor circuit are analyzed and compared. First, the charging and equalizing system is modeled as the switched system and the system observability is proved. The decentralized control and consensus control are analyzed and their shortages are presented. Then, the leader-follower cooperative control is proposed to improve the charging time while keeping the equalization performance. Meanwhile, the PI observer is designed to estimate the internal capacitance voltage of an SC precisely to avoid the effect of equal series resistance. The control convergence is proved by using the Lyapunov stability and switched system theory. The experimental results show that the proposed method has much superiority and wide applicability than the existing methods for equalizing voltages of SCs.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Electrochemical Impedance Spectroscopy-Based Electric Circuit Modeling of
           Lithium–Sulfur Batteries During a Discharging State
    • Authors: Daniel-Ioan Stroe;Vaclav Knap;Maciej Swierczynski;Erik Schaltz;
      Pages: 631 - 637
      Abstract: Lithium-ion batteries are characterized by having a very good performance in terms of efficiency, lifetime, and self-discharge, which allowed them to become the major player in the electric vehicle (EV) applications. However, they were not able to totally overcome the EV range anxiety. Thus, a research is carried out nowadays to develop batteries with even higher gravimetric energy density, which should allow a substantial range increase. One of the technologies, which should be able to meet the range requirements is the lithium-sulfur (Li-S) battery. Thanks to the extensive research and development efforts, these cells are close to enter the market, being evaluate in various projects. In this paper, we have proposed an electrical circuit model for a Li-S pouch cell, which was parameterized based on extensive electrochemical impedance spectroscopy measurements. The developed model was verified using static and pulse discharge profiles, showing a good accuracy in predicting the voltage of the tested Li-S battery cell.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Incorporating Battery Energy Storage Systems Into Multi-MW Grid Connected
           PV Systems
    • Authors: Vandana Rallabandi;Oluwaseun M. Akeyo;Nicholas Jewell;Dan M. Ionel;
      Pages: 638 - 647
      Abstract: This paper analyzes the configuration, design, and operation of multi-MW grid connected solar photovoltaic (PV) systems with practical test cases provided by a 10-MW field development. In order to improve the capacity factor, the PV system operates at its maximum power point during periods of lower irradiance, and the power output is limited to a rated value at high irradiance. The proposed configuration also incorporates a utility scale battery energy storage system (BESS) connected to the grid through an independent inverter and benefits of the experience gained with a 1-MW 2-MWh BESS large demonstrator. The BESS power smoothing and frequency regulation capabilities are illustrated though combined theoretical and experimental studies. The behavior of the grid connected PV and BESS combined system is studied using a modified IEEE 14 bus test system implemented in PSCAD/EMTDC. This paper also includes a sizing exercise for energy storage in order to provide dispatchable PV power.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Ancillary Services via VSIs in Microgrids With Maximum DC-Bus Voltage
           Utilization
    • Authors: Aswad Adib;Jacob Lamb;Behrooz Mirafzal;
      Pages: 648 - 658
      Abstract: Grid-interactive inverters allow distributed generation units to provide various ancillary services in microgrids. As the linear modulation region of inverters is restricted by the dc-bus voltage, providing ancillary services may drive the fundamental positive-sequence inverter voltage to the overmodulation region. Therefore, to operate in the linear modulation region the maximum active- and reactive-power of the inverter may have to be reduced unless pulsewidth modulation (PWM) references are adjusted. In this paper, an atypical PWM method is proposed for maximizing dc-bus utilization of grid-interactive two-level voltage source inverters (2L-VSI) providing ancillary services. Two important ancillary services, i.e., negative-sequence compensation and harmonic compensation are considered in this paper. The proposed method increases the maximum active- and reactive-power that a 2L-VSI can deliver when providing ancillary services by injecting a common-mode component in the references computed based on instantaneous reference magnitudes. The validity of the proposed technique is verified through simulation, as well as experimental data obtained using a 208-V three phase grid-connected 2L-VSI.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Fault-Tolerant Operation of DFIG-WT With Four-Switch Three-Phase Grid-Side
           Converter by Using Simplified SVPWM Technique and Compensation Schemes
    • Authors: Kai Ni;Yihua Hu;Guipeng Chen;Chun Gan;Xinhua Li;
      Pages: 659 - 669
      Abstract: In this paper, in response to the open-circuit fault scenario in the grid-side converter (GSC) of doubly fed induction generator-based wind turbines (DFIG-WTs), a fault-tolerant four-switch three-phase (FSTP) topology-based GSC is studied. Compared with other switch-level fault-tolerant converter topologies, fewer switches, less switching and conduction losses, and simpler converter structure are derived. A simplified space vector pulse width modulation (SVPWM) technique is proposed to improve the output current quality and reduce the computational complexity in the control process. Unified expressions of duty ratios for the two remaining healthy bridge arms are obtained. In addition, the three-phase unbalance phenomenon caused by the capacitive impedance in the faulty phase is analyzed from the ac point of view, and a current distortion compensation scheme is illustrated. Furthermore, a dc-bus voltage deviation suppression strategy is proposed to maximize the dc-bus voltage utilization rate and mitigate the damage to the dc-link capacitors. Simulations are carried out in MATLAB/Simulink2017a to demonstrate the validity of the proposed SVPWM technique and compensation schemes in FSTP GSC for a 1.5-MW grid-connected DFIG-WT when different working conditions are considered.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Second-Order Volterra-Filter-Based Control of a Solar PV-DSTATCOM System
           to Achieve Lyapunov's Stability
    • Authors: Neha Beniwal;Ikhlaq Hussain;Bhim Singh;
      Pages: 670 - 679
      Abstract: In this paper, a Volterra-filter-based control algorithm is developed to generate reference currents for a solar photovoltaic-distribution static compensator (PV-DSTATCOM) system in the distribution network. The developed control is analyzed for being stable under Lyapunov stability criterion; consequently, the error function of the system converges to zero asymptotically. The PV-DSTATCOM system is integrated to the grid to compensate the nonlinear load, while supplying solar PV array active power to the grid. The system is modeled in MATLAB and is executed on a developed prototype in the laboratory, under balanced, unbalanced loading conditions, and variable insolation conditions. Moreover, the harmonic distortion of the grid currents is observed under the IEEE-519 standard.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Design of a Cooperative Voltage Harmonic Compensation Strategy for
           Islanded Microgrids Combining Virtual Admittance and Repetitive Controller
           
    • Authors: Cristian Blanco;Francesco Tardelli;David Reigosa;Pericle Zanchetta;Fernando Briz;
      Pages: 680 - 688
      Abstract: Nonlinear loads (NLLs) in three-phase systems are known to produce current harmonics at -5, 7, -11, 13,... times the fundamental frequency. However, harmonics of the same frequencies are induced in microgrid voltage thereby reducing the power quality. Dedicated equipment, such as active power filters, can be used to compensate the microgrid harmonics. Alternatively, each distributed generation (DG) unit present in the microgrid can also be used for the same. The use of the virtual admittance concept combined with a proportional integral with resonant controller (PI-RES) control structure has previously been proposed as a harmonic compensation sharing strategy when multiple DGs operate in parallel. The drawback of this methodology is that a large number of RES controllers might be required to compensate for all the harmonic components induced by NLLs, increasing the tuning complexity as well as the execution time. This paper proposes the combined use of virtual admittance control loop and repetitive controller (RC) for harmonic compensation. The main advantage of the proposed method is that only one RC is required to compensate for all the harmonic components, significantly reducing the computational burden and the design complexity. The dynamic performance of the whole system is tested under variable NLL.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Analysis and Control of the Inductorless Boost Rectifier for Small-Power
           Wind-Energy Converters
    • Authors: Carlos Lumbreras;Juan Manuel Guerrero;Daniel Fernandez;David Diaz Reigosa;Cristina González-Moral;Fernando Briz;
      Pages: 689 - 700
      Abstract: This paper analyzes a cost-effective modification of the power topology commonly found in small wind turbine systems based on a passive rectifier and a boost converter. The boost-converter inductor and the input filter capacitor often placed at the rectifier output can be replaced by the generator-phase inductance. Different controller structures have been proposed for this low-cost inverter, but they have been focused on the converter itself rather than the overall turbine control. Moreover, only steady-state behavior has been demonstrated. This paper proposes a control structure only requiring retuning of the boost-current controller found in systems equipped with boost inductance, with other control loops remaining unchanged. The inductorless converter dynamic performance is studied and compared with the conventional topology in terms of current- and torque-control capability. The system efficiency, including the losses' distribution in the generator, is analyzed. Simulation and experimental results are presented to demonstrate the technical viability of this proposal.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Single-Stage SECS Interfaced With Grid Using ISOGI-FLL-Based Control
           Algorithm
    • Authors: Priyank Shah;Ikhlaq Hussain;Bhim Singh;
      Pages: 701 - 711
      Abstract: This paper proposes an improved second-order generalized integrator with frequency-locked loop (ISOGI-FLL) based control scheme for a grid-connected solar photovoltaic (PV) array fed voltage source converter (VSC) to mitigate the power quality problems. The steepest descent algorithm based maximum power point tracking is used to achieve the crest power from a solar PV array to improve solar power generation (SPG) into the grid as well as to maintain dc bus voltage of the VSC. The ISOGI-FLL-based control scheme is very effective for grid currents balancing and harmonics mitigation, at a variation of SPG and unity power factor operation. Simulated results are demonstrated using MATLAB/Simulink for load unbalancing and variation in solar insolation. The effectiveness of the proposed algorithm is demonstrated based on comparative performance with conventional algorithms. Test results of a developed prototype show satisfactory performance for different operating conditions like grid currents balancing, photovoltaic-distribution static compensator (PV-DSTATCOM) mode, and DSTATCOM-PV mode at variable solar insolation. Moreover, total harmonic distortions of grid voltages-currents are achieved within the limit of the IEEE-519 standard.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Fuzzy Logic Control of the Ultracapacitor Interface for Enhanced Transient
           Response and Voltage Stability of a DC Microgrid
    • Authors: Ramchandra Bhosale;Vivek Agarwal;
      Pages: 712 - 720
      Abstract: This paper proposes a novel fuzzy logic-based scheme to control the power flow from an ultracapacitor (UC) in a battery-UC hybrid energy storage system of a dc microgrid. The fuzzy logic controller determines the current reference for the UC converter to regulate the dc bus voltage tightly. Low-bandwidth controllers are designed for battery interfacing converter, which in combination with the proposed fuzzy controller, improve the quality of the current drawn from the battery. The fuzzy controller is simple to design and does not require the knowledge of the mathematical model of the system. It is a single input single output controller, which incurs low implementation complexity. It does not have “wind-up” issues as in the traditional proportional integral controller (PI)/PID controllers, which makes the controller relatively faster. In addition, the control strategy does not demand load current sensing. Low pass filter high pass filter (HPF) filters are also not used in this strategy, which eliminates the nonoptimal power-sharing problem associated with the frequency-based control strategies. The presented simulation results show the superiority of the proposed strategy over the conventional frequency-based control strategy. The hardware results validate the practical feasibility of the proposed scheme.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Parallel Operation of Unity Power Factor Rectifier for PMSG Wind Turbine
           System
    • Authors: Md Shafquat Ullah Khan;Ali I. Maswood;Mohd Tariq;Hossein Dehghani Tafti;Anshuman Tripathi;
      Pages: 721 - 731
      Abstract: Offshore wind power has inspired the fields of high voltage direct current (HVdc) for advantages of high power transmission in long distance. Hefty wind generators are making advanced multilevel rectifier and parallel operation of rectifiers popular choice of research with the aim to accommodate higher power. Issues of reliability and complexity of control are associated with active power electronic devices at such high power. This paper focuses on the novelty of operation of parallel three-phase diode rectifiers each with auxiliary bidirectional switching blocks (BSB) to improve their performance. For the system, maximum percentage power is commuted through the three-phase diode rectifier and paralleling further lessens the current stress on the semiconductor switches present in the BSBs. Competence of continuous operation at times of any specific branch failure provides the proposed system with higher modularity and reliability. The paralleled topology is controlled to obtain unity power factor at the generator output with low generator output-current harmonics using hysteresis current control. The dc-link voltage is controlled at a reference value, for various dynamic variations along with balanced capacitor voltages. The permanence of the proposed system is simulated for scenarios associated with variation of wind speed and load demands while various operation modes are tested on a 2.5-kW experimental setup.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Computational Intelligence-Based Demand Response Management in a Microgrid
    • Authors: Pramod Uthpala Herath;Vito Fusco;María Navarro Cáceres;Ganesh Kumar Venayagamoorthy;Stefano Squartini;Francesco Piazza;Juan Manuel Corchado;
      Pages: 732 - 740
      Abstract: A demand response management (DRM) system is proposed here, in which a service provider determines a mutual optimal solution for the utility and the customers in a microgrid setting. Such a system may find use with a service provider interacting with the respective customers and utilities under the existence of some DRM agreements. The service provider is an entity which acts at different levels of the electrical grid and carry out the optimization. The lowest level controls one “neighborhood” while higher levels of service providers control other lower level service providers. A microgrid consisting of a smart neighborhood of 12 customers was used as experimental case study and an advanced metering infrastructure (AMI) was implemented. Based on the formulation of an optimization problem which exploits price-responsive demand flexibility and the AMI infrastructure, a win-win-win strategy is presented. The interior-point method was used to solve the objective function and the application of particle swarm optimization and artificial immune systems for demand response were explored. Results for a range of typical scenarios were presented to demonstrate the effectiveness of the proposed demand-response management framework.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Surface Spiral Parallel and Antiparallel Winding Designs for High
           Efficiency, Low Spatial Voltage Stress, and Inductive Wireless Power
           Transfer Systems
    • Authors: Guangqi Zhu;Robert D. Lorenz;
      Pages: 741 - 750
      Abstract: Surface spiral winding (SSW) has been demonstrated to achieve low skin and proximity effects copper losses, and low air-gap magnetic flux density in MHz, kW level inductive wireless power transfer systems. The dielectric losses are still the limiting factor to further improve the coil-to-coil efficiency. In addition, high spatial voltage stress between the first turn and the end turn limits the maximum transferable power due to the voltage breakdown. This paper develops alternative coil configurations to reduce the copper loss, the dielectric losses, and the spatial voltage stress. Through emulating SSW using copper tubing, the dielectric losses and the spatial electric field between adjacent turns are reduced simultaneously. Two surface spiral parallel winding designs are proposed to reduce the equivalent series resistance and improve the coil-to-coil transfer efficiency. A surface spiral antiparallel winding design is proposed to equalize dynamic voltage stress between adjacent turns and improve power scalability while maintaining high coil-to-coil transfer efficiency.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Optimization of Electric Powertrains Based on Scalable Cost and
           Performance Models
    • Authors: Gabriel Domingues-Olavarría;Francisco J. Márquez-Fernández;Pontus Fyhr;Avo Reinap;Mats Andersson;Mats Alaküla;
      Pages: 751 - 764
      Abstract: This work presents a methodology for modeling, designing, and scaling the electromagnetic, mechanical, and thermal characteristics of the main components in an electric powertrain (excluding the battery), i.e., a power electronics converter, an electrical machine, and mechanical transmission. Additionally, a framework for estimating the cost of these components is described. This framework takes into consideration not only the material cost, but also all major manufacturing steps required for the production of a component and their dependence on expected production volumes. Moreover, a procedure to optimize the design of an electric powertrain, taking advantage of the aforementioned models, is proposed. Finally, the powertrain for a passenger electric vehicle is optimized using the proposed methodology, and the results are compared in terms of the electrical machine topology, powertrain concepts, cost, weight, gear ratio(s) in the transmission, and overloading capabilities.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Power Quality Assessment in Shipboard Microgrids Under Unbalanced and
           Harmonic AC Bus Voltage
    • Authors: Wenzhao Liu;Tomasz Tarasiuk;Mariusz Gorniak;Mehdi Savaghebi;Juan C. Vasquez;Chun-Lien Su;Josep M. Guerrero;
      Pages: 765 - 775
      Abstract: Power quality (PQ) is becoming more and more critical issue in shipboard microgrid systems (SMGs). Especially, the impact of voltage unbalance combined with harmonic distortions on the SMG behavior has not been fully investigated. In this paper, simple PQ assessment models and a series of controlled experiments are proposed and carried out in a real ship under sea-going conditions. The ship experimental results are presented and discussed considering nonlinear bow thruster load and high power ballast pump loads under unbalanced and harmonic voltage conditions. In addition, the analysis of bow thruster current harmonic surges during the ballast pump start-up is presented. Furthermore, the voltage/current distortions of a working generator, bow thruster and pump loads are analyzed. The paper provides a valuable analysis for coping with PQ issues in the SMG.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Extended Black-Box Model of Pantograph-Catenary Detachment Arc Considering
           Pantograph-Catenary Dynamics in Electrified Railway
    • Authors: Zhigang Liu;Hongyi Zhou;Ke Huang;Yang Song;Zongsheng Zheng;Ye Cheng;
      Pages: 776 - 785
      Abstract: With the increase of the train speed, the pantograph-catenary (PC) detachment becomes more frequent, which results in more serious PC detachment arc. In order to analyze the influence of PC detachment arc on the train system, several arc models are established. However, these models do not consider the actual PC detachment process. In this paper, an extended black-box model of PC arc is proposed, which considers the dynamic detachment process of PC based on the PC dynamics. First, the Habedank arc model is presented and the relationship of the PC detachment distance with the arc voltage and arc dissipated power is established. Next, the dynamic detachment trajectory is obtained from the dynamic simulation of the PC structure model. Then, by introducing the dynamic PC detachment trajectory model into the arc model, the dynamic arc model is built. Finally, the performance of the arc current and arc voltage is analyzed and the effectiveness of the dynamic arc model is verified.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Modeling and Prototype of a Dynamic Wireless Charging System Using LSPS
           Compensation Topology
    • Authors: Glauber de Freitas Lima;Ruben Barros Godoy;
      Pages: 786 - 793
      Abstract: The proposed paper presents the development of a highly efficient and highly immune misalignment tolerant loosely coupled inductive power transfer system using dynamic wireless power transfer concept to charge a 48-V battery bank at 500 W through a 16-cm airgap. The purpose of this work is to investigate the influence of a third coil functioning as a transmitter coil. The resonant circuit as well as the electronic power converters used to implement a prototype are deeply explained.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Optimal Integration of Hybrid Supercapacitor and IPT System for a
           Free-Catenary Tramway
    • Authors: Luigi Pio Di Noia;Fabio Genduso;Rosario Miceli;Renato Rizzo;
      Pages: 794 - 801
      Abstract: The aim of the paper is the study of an optimal integration of a supercapacitor-based storage system and inductive power transfer system for the free-catenary operation of a tramway. Starting from the definition of the topology of inductive power transfer system, we propose and analyze a design procedure for the pads of the inductive power system. In the second part of the paper, an optimal integration strategy for the correct size of on-board supercapacitors and the power of the inductive energy transfer are proposed. The results obtained by means of numerical simulations are discussed.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Factors that Influence the Performance of a Two-Rotating Disks-Type
           Tribo-Aero-Electrostatic Separator for Micronized WEEE
    • Authors: Imed Eddine Achouri;Thami Zeghloul;Gontran Richard;Karim Medles;Hamou Nouri;Lucian Dascalescu;
      Pages: 802 - 811
      Abstract: Electrostatic separation of granular plastics mixtures has become a well-established technology, with industrial applications in the area of waste electric and electronic equipment recycling. The aim of this study was to pave the way to industrial application of a new two-rotating disks-type tribo-aero-electrostatic separator for finely grinded matter (i.e., granule diameter
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Factors That Affect Tribocharging of Polyethylene (PE) Granules After
           Exposure to a Dielectric Barrier Discharge (DBD)
    • Authors: Gontran Richard;Amar Tilmatine;Ahlem Benabderrahmane;Thami Zeghloul;Karim Medles;Lucian Dascalescu;
      Pages: 812 - 816
      Abstract: Triboelectric charging is used in many applications including electricity nanogeneration, safety or electrostatic separation of insulating materials. Insulating granules charge must be the highest in electrostatic separators so that the electric field forces allow their separation. Dielectric barrier discharge (DBD), used for ozone production, depollution or surface treatment, is able to change the triboelectric properties of insulating materials. The aim of this study is to improve the triboelectric charging of polyethylene particles by exposing them to an atmospheric DBD. Signal shape, exposure duration, voltage amplitude, and frequency, which rule the DBD, are studied. After exposing the particles to DBD, they are charged in a vibratory device during 5 min. Then, particles are put in a Faraday pail connected to an electrostatic voltmeter to measure the acquired charge. Results show that the square waveform has the best effect and that the duration of the DBD treatment should not exceed 10 s, for the amplitude of the applied voltage of 21 kV.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Mass Production of Nanocomposites Using Electrospinning
    • Authors: Chitral J. Angammana;Ryan J. Gerakopulos;Shesha H. Jayaram;
      Pages: 817 - 824
      Abstract: Many conventional polymer processing technologies for compounding micro-/nanocomposites are known in the field. These methods include the direct use of high shear mixers, roll mixers, Banbury mixers, and extruders. With recent interest in advanced composites with nanoscale fillers, efforts have been made to enhance conventional processing technologies as the imposed input energy is often ineffective at breaching the energy barrier to breakup agglomerated nanofiller structures. Electrospinning is a simple, inexpensive process that can be used to produce continuous fibers from submicron to nanometer diameter scale through an electrically charged polymer jet. In this paper, authors present a rotary electrospinning method developed to produce nanocomposites at mass scale by using simultaneously mechanical and electrical forces with a proprietary apparatus. A case study using silica nanoparticles and silicone rubber matrix is presented to demonstrate the capability of the above method of dispersing nanoparticles in highly viscous polymer matrix materials.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Improvement in Molecular-Level Adhesive Strength of PTFE Film Treated by
           Atmospheric Plasma Combined Processing
    • Authors: Keita Hori;Syunsuke Fujimoto;Yudai Togashi;Tomoyuki Kuroki;Masaaki Okubo;
      Pages: 825 - 832
      Abstract: Atmospheric pressure plasma graft polymerization-treated fluorocarbon plastics are bonded with a metal, to evaluate adhesiveness. In this research, the atmospheric nonthermal plasma graft polymerization technique is used in treating the surface of polytetrafluoroethylene (PTFE) in a dry process, capable of reducing environmental loading. The treated PTFE is joined with the stainless steel plate to perform a peeling test. We examine the peeling strength and the best condition for practical application using peeling strength as an optimization variable. A concrete numerical target is 2 N/mm, which is the standard adhesive strength applicable for industry uses. To conduct the graft polymerization, we use a monomer such as acrylic acid (CH2 = CHCOOH) and target material such as PTFE. Peeling strength is maximized (averaged value of 1.56 N/mm, largest value of 2.0 N/mm) when the temperature of the acrylic acid is 60 °C and the Ar main flow rate is 40 L/min. Influence of plasma torch cover on peeling strength and entrained flow near the torch are investigated to realize the stronger adhesion, and better shape of the cover is determined. Furthermore, by analyzing X-ray photoelectron spectroscopy and scanning electron microscope images, we evaluate the atmospheric pressure plasma graft polymerization process from a different perspective and search for optimal operating conditions of the processing method.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Numerical Study of the Suitable Precharger Grounded Electrode Length in
           Two-Stage-Type Electrostatic Precipitators
    • Authors: Yoshihiro Kawada;Hirotaka Shimizu;Akinori Zukeran;
      Pages: 833 - 839
      Abstract: The two-stage-type electrostatic precipitator has been used only in limited applications because of its need to accommodate a large flow rate with its compact size. A two-stage-type electrostatic precipitator comprises a precharger and a collecting unit. The grounded electrode in the precharger is generally designed to be quite short. Previous studies on the influence of the grounded electrode length in the precharger on collection efficiency have reported that the amount of particle charge through the precharger decreases for grounded electrodes that are 20- or 80-mm long. The electric field and space charge distributions were calculated for various grounded electrode lengths using the finite-element method, where the ion density distribution was used as the space charge distribution. For a 20-mm-long grounded electrode, the electric field intensity around the high-voltage wire electrode decreased. Additionally, the electric field intensity distribution at close proximity to the grounded electrode has two additional peaks due to the edges of the electrode. With the 80-mm-long grounded electrode, the peaks of the electric field intensity distribution were outside of the high-ion-density region. These results show that the optimal grounded electrode length for particle charging is about three times the distance between the grounded electrode and the high-voltage wire electrode.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Adaptive Artificial Neural Network-Based Models for Instantaneous Power
           Estimation Enhancement in Electric Vehicles’ Li-Ion Batteries
    • Authors: Ala A. Hussein;
      Pages: 840 - 849
      Abstract: This paper investigates the role of artificial neural networks in enhancing the accuracy of instantaneous power estimation of electric vehicles' batteries. In electric vehicles, a battery is used as a main or complementary bidirectional power source. To optimize the energy management of the vehicle, the power sourced or sinked by the battery must be estimated in real time under any condition. The power of the battery is a function of many variables including the current, the state of charge, the ambient temperature, and the state of health. This paper evaluates some existing equivalent circuit models for estimating the instantaneous power of electric vehicles' batteries and proposes new artificial neural network-based models to enhance the power estimation accuracy. The experimental data obtained by performing standardized electric vehicle tests using a 3.6-V/16.5-Ah lithium-ion battery cell and a 12.8-V/150-Ah lithium-ion battery pack are presented and used for models' evaluation.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Interphase Fault Relaying Scheme to Mitigate Sympathetic Tripping in
           Meshed Distribution System
    • Authors: Ankita Sharma;Bijaya Ketan Panigrahi;
      Pages: 850 - 857
      Abstract: In a distribution system when fault occurs, prior operation of any other relay which is not designated as the primary relay causes undesired shedding of a healthy line. This phenomena of unwanted relay operation is termed as sympathetic tripping. For appropriate relay operation, issue of sympathetic tripping is required to be considered while addressing relay coordination problem. This paper proposes a phase fault protection scheme, which mitigates the issue of sympathetic tripping in the meshed network. The undesired relay operation in the network is restricted by imposing some additional constraints on the conventional relay coordination problem. The proposed nonlinear optimization problem is solved by using Shannon-Wiener differential evolution algorithm. Procured optimal relay settings will provide efficient protection against each phase fault without causing sympathetic tripping. The efficacy of the proposed algorithm is examined on modified IEEE-8-bus system, IEEE-14-bus system, and IEEE-30-bus system. The obtained results are verified by using GE Mutilin, model-750/760 overcurrent relay in ETAP (industrial simulation software).
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Multipulse AC–DC Converter Fed 15-Level Cascaded MLI-Based IVCIMD for
           Medium-Power Application
    • Authors: Bhim Singh;Piyush Kant;
      Pages: 858 - 868
      Abstract: In this paper, a multipulse ac-dc converter fed multilevel inverter (MLI)-based indirect vector controlled induction motor drive (IVCIMD) is proposed for medium-power application. A 54-pulse ac-dc converter is utilized at the supply side to suppress the input current total harmonic distortion, as per the IEEE-519 standard. Mainly three separate isolated transformers are utilized and each transformer is configured as an 18-pulse ac-dc converter. Due to the phase shift in primary windings, these three transformers are reconfigured as a 54-pulse ac-dc converter. A 15-level binary-based cascaded MLI is utilized at the motor side to enhance the required performance of IVCIMD. A 15-level inverter is switched at fundamental frequency, which ensures the very low switching losses in the proposed IVCIMD. A modified nearest level modulation strategy is proposed to achieve fundamental switching frequency. The performance of the proposed IVCIMD is simulated at various operating conditions by utilizing Simulink/MATLAB platform. Simulated results are validated with experimental results on a developed prototype in the laboratory to show its usefulness for medium-power applications.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • GI-Based Control Scheme for Single-Stage Grid Interfaced SECS for Power
           Quality Improvement
    • Authors: Priyank Shah;Ikhlaq Hussain;Bhim Singh;Ambrish Chandra;Kamal Al-Haddad;
      Pages: 869 - 881
      Abstract: This paper presents an improved generalized integrator (GI)-based control with a frequency locked loop for multifunctional three-phase single-stage grid interfaced solar energy conversion system for power quality enhancement of the distribution network under abnormal grid conditions. The perturb and observe-based maximum power point tracking technique is utilized to obtain peak power from solar photovoltaic array under varying atmospheric conditions. This control scheme provides unity power factor operation, load balancing, harmonics mitigation, and reactive power compensation. The improved GI control algorithm has an advantage of better dc offset and harmonics rejection capabilities as compared to a conventional second-order GI algorithm. To substantiate the control scheme, tests are performed on a paradigm in the research laboratory for manifold operating conditions. Test results show the satisfactory behavior under steady state and dynamic operating scenario such as unbalanced load, solar irradiations variation, voltage sag, and swell and distorted voltage grid. The total harmonic distortions of the grid voltages-currents are achieved within constraints of grid code compliance of an IEEE 519 and 1564 standards.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Frequency Adaptive Prefiltering Stage for Differentiation-Based Control of
           Shunt Active Filter Under Polluted Grid Conditions
    • Authors: Sanchit Mishra;Ikhlaq Hussain;Bhim Singh;Ambrish Chandra;Kamal Al-Haddad;Priyank Shah;
      Pages: 882 - 891
      Abstract: A differentiation-based control method for a shunt active power filter is used in this paper for functioning in the presence of grid voltages distortion and imbalances. To enable the fast and accurate estimation of the variables in the presence of unbalancing or distortion in the grid voltages, a prefiltering scheme is considered based on the dual second-order generalized integrator approach. The signal recomposition performed by the prefilter isolates the harmonics from the voltage and current waveforms, and the differentiator frequency locked loop (dFLL) is able to estimate the frequency of the waveforms, which is used as a feedback for the prefilter, thus making the system frequency adaptive. The control algorithm is validated with both simulation studies. The prototype of an active power filter is developed, which carried out current compensation robustly, demonstrating the speed and accuracy of the system even under distorted grid conditions by achieved total harmonic distortions (THDs) of the grid currents within limits (less than 5%) as dictated by IEEE Std. 519-2014.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Structured H-Infinity Controller for an Uncertain Deregulated Power System
    • Authors: Arlene Davidson Rosaline;Ushakumari Somarajan;
      Pages: 892 - 906
      Abstract: A deregulated power system is considered to be a highly complex uncertain system due to the presence of multiple bilateral transactions. Load frequency control in such a system hence assumes significance because of the challenging nature of operation and therefore use of robust controllers is imperative. Conventional robust controller designs give higher order controllers and hence restricts its application in the industry. But the alternative is to use structured H-infinity controllers, which give sufficiently lower-order controllers and can be used in system with nonlinearities. In this paper, structured H-infinity controller has been designed for a deregulated power system considering the effect of nonlinearities like generation rate constraint, governor deadband, and time delay associated with communication network in the system from practical point of view. These physical constraints demand an electrical energy storage system. Hence, load frequency control is accomplished with a structured H-infinity controller supplemented with redox flow battery in each area of a two-area deregulated power system consisting of GENCOs of reheat thermal type.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Hybrid SMES Based Reactive Power Dispatch by Cuckoo Search Algorithm
    • Authors: Syamasree Biswas Raha;Kamal Krishna Mandal;Niladri Chakraborty;
      Pages: 907 - 917
      Abstract: Superconducting magnetic energy storage (SMES) systems are one of the emerging technologies which might gain importance. This technology help to meet peak electrical load demands by providing time varying energy management along with voltage stability. Therefore, it can be suitably utilized to solve reactive power dispatch (RPD) for nonrestructured and restructured scenarios. The RPD involving multilateral power transactions frequently causes huge real power losses with dynamic voltage limit crossover. These are commonly tackled by capacitor placements. Due to its static behavior, the capacitors are unable to provide desired results every time. In this context, SMES can generate the desired solutions. However, the SMES also have limited power applications due to their higher installation and operating costs. Therefore, if the hybrid compensators involving capacitor and SMES are optimally chosen, the cost of operation will reduce but effective solution may be generated. This further helps to improve global welfare of the restructured network. In this work, hybrid capacitor-SMES based var compensation is utilized to solve the RPD for the nonrestructured and restructured network. The sitting and sizing of the compensators are assigned by the cuckoo search algorithm. The hybrid capacitor-SMESs achieved 3.93% more power loss reduction and 1.53 times improved economics compared to single capacitor based solution for the nonrestructured IEEE 118 bus network. Further, the hybrid capacitor-SMESs obtained 0.2362% improved global welfare from the study having no var compensators for restructured RPD considering IEEE 118 bus network.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Implementation of Immune Feedback Control Algorithm for Distribution
           Static Compensator
    • Authors: Manoj Badoni;Alka Singh;Bhim Singh;
      Pages: 918 - 927
      Abstract: This paper presents an immune feedback control algorithm for a three-phase distribution static compensator (DSTATCOM) to mitigate several power quality problems such as harmonics, reactive power, and load unbalancing at distribution level. A configuration chosen for DSTATCOM is based on a three-phase voltage source converter (VSC), which is suitably controlled as a shunt compensator for performing these functions. The underlying principle of an immune feedback is based on adaptive control and the designed control estimates fundamental reference grid currents from nonlinear load currents. This control algorithm proposed for DSTATCOM, is validated for maintaining power factor to unity, load balancing, and harmonics reduction of supply currents. An improved performance of immune feedback control is presented along with its comparison with conventional control algorithms such as dq frame, normalized least mean square and other recently developed control algorithms such as leaky least mean square, leaky least mean fourth, and synchronous extraction. Experimental results are obtained with the proposed control, which is tested on a prototype developed in the laboratory using a VSC. It is observed from simulation and experimental results that the proposed control algorithm of DSTATCOM is able to achieve mitigation of most of the power quality problems at the distribution level.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • A Modified PWM Scheme to Improve Performance of a Single-Phase
           Active-Front-End Impedance Source Inverter
    • Authors: Anil Gambhir;Santanu K. Mishra;Avinash Joshi;
      Pages: 928 - 942
      Abstract: Impedance source inverters (ISIs) are gaining attention due to features such as single-stage conversion, buck-boost capability, and inherent shoot-through protection. To maintain the required ac output voltage, typically ISIs are operated at a higher dc-link voltage due to constrained modulation index. This also increases voltage stress across capacitors and switches of the converter. This voltage stress is approximately double compared to that of voltage source inverter with preboost stage (Boost-VSI). To mitigate this problem, a new pulsewidth modulation (PWM) scheme for the active-front-end based ISIs (AFE-ISIs) is proposed. The proposed scheme enables the ISIs to produce high ac gain with lower voltage stress across the capacitor and switches. In other words, the proposed scheme blends the advantages of Boost-VSI into ISIs. With the new PWM scheme, there are also reductions in output voltage total harmonic distortion, switching frequency ripple in the inductor current, and power loss in the converter. A prototype of the current-fed switched inverter, an AFE-ISI, is designed, and the proposed PWM scheme is implemented. Experimental results obtained are in accordance with the proposed theory and show that the voltage stress has reduced from 325 V to 203 V for an ac output of 110 V.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Resilient Cyber Infrastructure for the Minimum Wind Curtailment Remedial
           Control Scheme
    • Authors: Vignesh Venkata Gopala Krishnan;Shyam Gopal;Ren Liu;Alex Askerman;Anurag Srivastava;David Bakken;Patrick Panciatici;
      Pages: 943 - 953
      Abstract: Integration of distributed energy resources has been significantly increasing in the electric power grid. One of the predominant renewable energy sources, wind energy, possess a significant challenge for grid operations, due to its intermittency, uncertainity, and variability. In changing operating conditions with wind uncertainity, part of wind may need to be curtailed for the safe utilization of the transmission system. In order to minimize the wind power curtailment and to keep the power flow on a transmission line under limits, a cyber resilient distributed remedial action scheme (DRAS) is developed in this paper. The remedial action scheme (RAS) is formulated as an optimization problem, considering the real-power flow constraints of the transmission lines and given wind variability. In this paper, DRAS is developed to operate even with failures in the computing nodes to make it cyber-resilient. Distributed simplex algorithm is used for optimization in the distributed RAS. The DRAS is implemented in a decentralized platform called Resilient Information Architecture Platform for Smart Grid to enable cyber resiliency of DRAS. The effectiveness of the proposed approach is validated through offline simulations of the New England 39-bus system and online simulations of IEEE 14-bus test system. A cyber-physical testbed utilizing real time digital simulator, phasor measurement units, and BeagleBones has been used for the online simulation and validation of the developed cyber-resilient RAS.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Islanding Detection of Distributed Generation Based on Rate of Change of
           Exciter Voltage With Circuit Breaker Switching Strategy
    • Authors: Ali Rostami;Amin Jalilian;Mehrdad Tarafdar Hagh;Kashem M. Muttaqi;Javad Olamaei;
      Pages: 954 - 963
      Abstract: This paper presents a new islanding detection method for synchronous distributed generation (DG). The proposed method is developed based on the combination of rate of change of exciter voltage (RCEV) and open-close circuit breaker (OCCB) at a DG connection point. Whenever the RCEV parameter is not sufficient enough to detect an islanding condition efficiently and correctly, the OCCB strategy will be triggered. The proposed OCCB strategy sends a switching command to one phase of the three-phase circuit breaker (CB), which connects the DG to the grid. In this way, the CB will be immediately opened and then closed. This switching condition will cause a variation in the value of RCEV. This variation is small for the conditions when DG operates in parallel with the main grid, whereas it will be large during the occurrence of islanding. The implementation of the proposed strategy is cost-effective because it only uses the CB at the DG output and does not require any extra equipment. The proposed approach is tested on two different systems including a hypothetical power system and the IEEE 33-bus test system in MATLAB/Simulink environment. The simulation results show that the proposed method eliminates the nondetection zone and also reveals high accuracy compared with previously introduced methods. Moreover, it has been proved that the performance of the proposed approach is not affected by DG capacity, DG location, the number of DG units, as well as network configuration.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Switched-Boost Action Based Multiport Converter
    • Authors: Santanu K. Mishra;Khirod Kumar Nayak;Mandeep Singh Rana;Vimala Dharmarajan;
      Pages: 964 - 975
      Abstract: Multioutput converters with single input source are currently studied as an alternative to conventional dc-dc topologies in order to improve power density in low-power multiload applications. This paper reviews three different ways in which a boost topology can be customized to supply multiple outputs. The first way uses a charge-sharing approach using individual switches to distribute inductor energy to different capacitors. The second method of creating a multiport converter (MPC) combines two converters with similar front end to generate two outputs using only one controlled switch. Using this method, a boost converter can be combined with single-ended primary-inductor converter (SEPIC), Cuk, and current source converter topologies. The third method uses time multiplexing of switches to produce two regulated ports and is referred to as switched-boost action. This method uses relatively less number of switches and allows regulation and control of all the outputs. Practical utility of switched-boost action based MPC is reported in this paper. This switched-boost MPC is applied to a renewable power converter system to interface a solar panel, a battery, and home loads to produce a 12-V and a 48-V bus. The 12-V bus is interfaced to battery and capable of optimally charging the battery in constant current-constant voltage (CC-CV) mode. The converter is demonstrated to operate with solar panel as it supplies a 12-V battery and a 48-V load bus. When the solar power is not available, the converter automatically goes into a mode in which the 12-V battery supplies the loads on the 48-V bus.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Modeling and Control of an Irrigation Station Process Using Heterogeneous
           Cuckoo Search Algorithm and Fuzzy Logic Controller
    • Authors: Jaouher Chrouta;Wael Chakchouk;Abderrahmen Zaafouri;Mohamed Jemli;
      Pages: 976 - 990
      Abstract: Water is becoming a precious and very scarce resource in many countries due to an increasing demand in agricultural and industrial fields as well as population growth. Therefore, we have to optimize the water resources from hydraulic systems, in order to decrease water losses. In this context, many research studies focused on modeling, identifying, and controlling of hydraulic systems, especially for agricultural use. In this paper, we will investigate the problem of identification and control design for an irrigation process through an academic irrigation station (IS) system. Two main objectives will be reached. On the one hand, we will provide a new optimal Takagi-Sugeno (T-S) fuzzy model of our IS process. The optimal model is obtained through using a fuzzy parameters searching strategy, named intelligent T-S modeling. This last, is associated with a heterogeneous cuckoo search (HeCoS) strategy based on the quantum mechanism. On the other hand, we will devote a lot to the synthesis of an optimal control law by using fuzzy logic control (FLC) to ensure the global stability of the closed-loop system. The proposed FLC has two major advantages. First, it does not require a complex process to find a common Lyapunov function for a large number of fuzzy subsystems. Therefore, the designed procedure of the proposed FLC is much simpler. Second, by employing the FLC, the closed-loop system performance can be designed. Finally, and as a result, the HeCoS strategy is well adopted to find an optimal model for the real processes with high accuracy and strong generalization ability. Experimental results applied to the IS demonstrate the merits of the proposed FLC.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Photometric and Electrical Characterizations of Large-Area OLEDs Aged
           Under Thermal and Electrical Stresses
    • Authors: Alaa Alchaddoud;Laurent Canale;Ghassan Ibrahem;Georges Zissis;
      Pages: 991 - 995
      Abstract: The aim of this paper is to identify the electrical signatures of degradations of large-area organic light-emitting diodes (OLEDs) (41 cm2 active area), subjected to various stress conditions. Three Philips GL55 OLEDs were stressed under three distinct temperature values: 23 °C, 40 °C, and 60 °C at a stress current density of J = 15 mA/cm2 (rated current density: Jn = 9.49 mA/cm2). Under thermal and electrical stresses, an increase of the operating voltage was observed with stress time but thermal stress alone did neither affect the operating voltage nor the luminance values up to 60 °C.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Practical Issues in the Design of Wireless Sensors Supplied by Energy
           Harvesting Thermoelectric Generators
    • Authors: Juan M. Lopera;Héctor del Arco Rodríguez;Jesús María Pérez Pereira;Alejandro Rodríguez de Castro;José Luis Rendueles Vigil;
      Pages: 996 - 1005
      Abstract: The use of energy harvesting for supplying wireless sensors becomes a new market opportunity. During last years, new low power transmitters, and also power conversion ICs specifically designed for energy harvesting, have become commercially available. However, as any other power supply circuit, the specific load behavior affects to the power converter, doing that just joining the two parts takes to a nonfunctional device. In this paper, we will measure experimentally the transmitter current of some technologies, for the several sensor states. Some practical issues that affect directly the sensor design will be shown. With this information, some required modifications in the power stage will be proposed. A complete temperature sensor design and assembly is showed. The sensor has been tested in a tandem cold mill, and several experimental results are included.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Improvement of MV Cascaded H-Bridge Inverter (CHBI) VFD Availability for
           High-Power ESP Oil Wells
    • Authors: Fabio Pereira Feletto;Robert A. Durham;Edson da Costa Bortoni;João Guilherme de Carvalho Costa;
      Pages: 1006 - 1011
      Abstract: Artificial lift systems are generally applied in the petroleum industry to provide the energy to transfer the oil from the reservoir to the surface. Electrical submersible pump (ESP) system is an artificial lift method extensively used in recovery. The maintenance cost of ESP and associate equipment is very high; therefore, the maximum availability of the system components is continuously sought. The aim of this paper is at analyzing the availability and reliability of frequency converters applied to medium voltage (MV) multilevel cascaded H-bridge inverters topology for ESP. A method to increase availability of MV frequency drives is thus proposed, enabling fewer losses in the production and a greater return on the economic investment (ROI).
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Effective Transient-Free Capacitor Switching (TFCS) for Large Motor
           Starting on MV Systems
    • Authors: Dwaraka S. Padimiti;Michael B. Christian;Jukka Jarvinen;
      Pages: 1012 - 1020
      Abstract: Capacitor bank switching on medium voltage power systems has been in practice for nearly half a century. However, capacitor bank switching causes high inrush currents and voltage transients [as high as 3.0 per unit (p.u.)] in the power distribution system potentially damaging electrical equipment, impacting the system reliability and power quality. Additionally, capacitor switching transients affect the life of the capacitor itself and can cause damage or sudden failure. Pipeline substations are often located in remote areas with insufficient short circuit capacity available on the distribution system to start a large medium voltage induction motor. In many such instances, the end user often ends up using a medium voltage soft-starter, a higher rated MVA transformer in conjunction with a reactor start, or a low inrush motor with less than ideal motor efficiency. This paper introduces a transient-free synchronous capacitor switching system for large motor starting on MV power distribution systems that can be used with a traditional capacitor bank system while restricting the voltage transient to less than 1.05 p.u. during capacitor switching. This solution is economically efficient and more reliable compared with other motor starting methods. Alternatively, in lieu of a low inrush, low-efficiency induction motor in some applications, a motor start solution of transient-free capacitor switching, and capacitor bank with regular induction machine can be applied more economically.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Online Partial Discharge Insulation Condition Monitoring of Complete
           High-Voltage Networks
    • Authors: Lee Andrew Renforth;Riccardo Giussani;Michael T. Mendiola;Lewis Dodd;
      Pages: 1021 - 1029
      Abstract: Renforth et al. in 2017 present a novel online partial discharge (OLPD) high-voltage (HV) insulation condition monitoring (CM) solution to monitor complete HV networks in petrochemical and other critical industry facilities. Continuous, 24/7 OLPD insulation monitoring of in-service cables, switchgear, transformers, and rotating machines operating at 3000 V and above provides operators with an early warning against incipient HV insulation faults that manifest themselves through high PD activity. Knowledge of the type, severity, and source of any site(s) of PD across the HV network (including remotely connected plant such as Ex/ATEX HV motors located in hazardous gas zones) enables pinpointed preventative maintenance interventions to be made to the HV insulation system during planned maintenance turnarounds to avoid unplanned outages. To monitor a complete HV network, OLPD sensors and monitoring nodes are distributed at strategic locations across the network. The CM data from the distributed nodes are passed via Ethernet/LAN to a partial discharge monitoring server (PDMS) located at the control center of the facility with a secure internet connection. The PDMS operates an advanced OLPD monitoring database for the logging, display, benchmarking, trending, and visualization of the PD monitoring data on a graphical user interface. The insulation condition criticality (from 0% to 100%) of each phase of all of the individual HV plant items monitored is presented on a series of mimic screens of the HV network single-line diagram. This paper concludes with a case study of a complete HV network OLPD monitoring design solution implemented at a large, crude-oil processing facility in Eurasia.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
  • Considerations on the New Requirements for Electrical Installations in
           Hazardous Locations
    • Authors: Estellito Rangel;Carlos Azevedo Sanguedo;
      Pages: 1030 - 1036
      Abstract: This paper debates the requirements mentioned in some of the current editions of the International Electrotechnical Commission standards related to equipment and installations in hazardous locations. The main requirements recently introduced are shown, and some points of concern from installers are highlighted.
      PubDate: Jan.-Feb. 2019
      Issue No: Vol. 55, No. 1 (2019)
       
 
 
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