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Power Electronics, IET

Issue 2 • Date February 2014

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Displaying Results 1 - 23 of 23
  • Lossless passive snubber for double ended flyback converter with passive clamp circuit

    Publication Year: 2014 , Page(s): 245 - 250
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (757 KB)  

    Transformer leakage inductance in flyback converter results in high switch losses and stresses. For practical implementation of this converter snubber and clamp circuits are necessary. In this study a new passive lossless snubber and clamp circuit for double ended flyback converter is introduced. Operation of the new snubber is independent of load, and the converter duty cycle can be changed in a wide range. The proposed converter is analysed and experimental results are presented to justify the theoretical analysis. View full abstract»

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  • Support vector regression-based distortion compensator for three-phase DC??AC boost-inverters: analysis and experiments

    Publication Year: 2014 , Page(s): 251 - 258
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (996 KB)  

    Distortion existence in output of power electronics DC??AC converters is inevitable. The amount of distortion in boosttype converters is higher than other types, which is difficult to mitigate. This study introduces a new modification of three-phase boost-inverters in order to mitigate excessive distortions. The compensation process is modified to take advantage of non-linear operation of boost converters and a differential connection of DC??DC converters is employed. Considering DC??AC boostinverter, it is shown that the outcomes are usually different from the expected desired waveforms. This is because of the nonlinear structure of the switching converter. Thus, a compensation method based on support vector regression (SVR) is proposed in a way that the desired waveforms appear at the output of the converter. Analysis and simulations are first introduced for defining the limitations of a boost-inverter because of the non-linear structure. Then, the simulated SVR applied to the external-layer control, comparing the effects of the suggested algorithm with those of the uncompensated cases. Furthermore, practical verification is taken place on an implemented 500 VA boost-inverter in order to confirm the proposed technique as well as theoretical analysis and simulations. The proposal is particularly useful when considering high penetration of inverter-based interfaces for renewable energy sources such as solar panels. View full abstract»

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  • Coupled-inductor single-stage boost inverter for grid-connected photovoltaic system

    Publication Year: 2014 , Page(s): 259 - 270
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1255 KB)  

    This study presents a coupled-inductor single-stage boost inverter for grid-connected photovoltaic (PV) system, which can realise boosting when the PV array voltage is lower than the grid voltage, converting dc voltage into ac voltage, feeding current to the grid with high-power factor and maximum power point tracking (MPPT) together. By introducing an impedance network including coupled inductor in front of the three-phase inverter bridge, and adjusting the previously forbidden shoot-through zero state, the converter can step up input voltage to a higher voltage level. System reliability is also improved by using shoot-through zero state as a normal operation mode. Cost can be reduced by single-stage operation and also by using economical MPPT method only via grid current. Theoretical analysis, simulation and experimental results are presented to verify its good performance. View full abstract»

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  • Integral-resonant control for stand-alone voltage source inverters

    Publication Year: 2014 , Page(s): 271 - 278
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1101 KB)  

    This study deals with a newly-conceived voltage control method for three-phase four-leg voltage source inverters (VSIs) which are being required in autonomous power generating units devoted to supply both three-phase and single-phase electrical loads in four-wire electric power distribution systems. To deal with VSI operating conditions providing three-phase voltage supply of both unbalanced loads and non-linear loads, an integral + resonant (I + R) voltage control structure is discussed and experimentally verified by means of a 25 kVA rated power converter prototype. It is shown that the proposed voltage control allows simplifying the overall control configuration, achieving zero-overhead power factor regulation and fast compensation of load unbalances. Further to that, a complete current limiting strategy is described and tested under different load conditions. View full abstract»

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  • Improved passive snubbers suitable for single-phase isolated full-bridge boost power factor correction converter

    Publication Year: 2014 , Page(s): 279 - 288
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1322 KB)  

    In this study, two novel improved passive snubbers suitable for isolated full-bridge boost topology are proposed. The snubbers are composed of two capacitors, two inductors and four diodes. The voltage spike across the primary side of transformer is absorbed by one capacitor of the snubbers during a charging period, and by the other capacitor in the following charging period. The energy of capacitors can be transferred to the output side of the power factor correction (PFC) converter during one charging period by the resonance of the inductors and capacitors. Taking one improved snubber, for example the operational process of the original and the improved snubbers are analysed in a single-phase isolated full-bridge boost PFC converter. Furthermore, between the original and the improved snubbers, comparative analysis about the voltage and current stress, parameters limitation and the reliability are given. Finally, experimental study has been done on a laboratory-made single-phase PFC prototype, and the feasibility of the proposed method and the validity of the theoretical analysis are verified by the experimental results. View full abstract»

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  • Chaotic dynamics of a zero average dynamics controlled DC-DC Cuk converter

    Publication Year: 2014 , Page(s): 289 - 298
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (978 KB)  

    The undesirable subharmonics in periodically driven non-linear systems such as switching power converters is a more common problem in power electronic circuits. Such operations are usually avoided by modifying the circuit parameters which necessitates a proper understanding of the system. In the present study, non-linear dynamic behaviour in a zero average dynamics (ZAD) controlled DC??DC C?? uk converter is investigated. The effects of varying the control parameters on the qualitative behaviour of the system are studied in detail. Bifurcation analysis of a ZAD controlled DC??DC ?? Cuk converter has not been reported so far in the literature as it involves complex modelling and implementation of the overall control system. To reduce the complexity in deriving the map dynamics and computing the ZAD control parameters, a reduced order model is derived. Moment matching technique is used to obtain the reduced order model. It is found that for even small control parameter variations, the system exhibits period-doubling bifurcation. The dynamics of this converter system has been mathematically described and analysed with a simple discrete map. Computer simulations as well as experimental investigations are performed to study the qualitative behaviour of the system under variations of different parameters. The results offer useful information of parameter space for the design and operation of the converter in the desired fundamental stable regime. Finally, a time-delay component is included in the ZAD control strategy and it is shown that the onset of chaos can be delayed. View full abstract»

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  • High-efficiency dual-input converter with high-voltage gain and internal charge function

    Publication Year: 2014 , Page(s): 299 - 315
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (2150 KB)  

    In this study, a high-efficiency dual-input converter with an internal charge circuit is developed. The proposed coupledinductor- based converter can boost the voltages of two input power sources with different low-voltage levels to a controllable high-voltage DC bus. The high-voltage DC bus can be taken as the main power for a high-voltage DC load or the front terminal of a DC??AC inverter. The charge circuit inside the proposed dual-input converter can provide the redundant energy from the major source for the auxiliary power source (e.g. battery module) to save the manufacturing cost. According to the operation of power management, the operational states of the proposed dual-input converter can be divided into three situations including a standalone power-supply state, a charge state and a unify power-supply state. The techniques of voltage clamping and soft switching are employed in this converter, and the corresponding device specifications are adequately performed. Thus, the goal of high-efficiency dual-input power conversion with high-voltage gain can be achieved. Some experimental results via a 1.5 kW-level prototype are given to verify the effectiveness of the proposed dual-input converter in practical applications. View full abstract»

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  • Four hundred Hertz shunt active power filter for aircraft power grids

    Publication Year: 2014 , Page(s): 316 - 324
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1217 KB)  

    To fulfill the high reliability of the aeronautical application, a novel three-phase four-wire shunt active power filter (APF) is proposed in this study. In this proposed configuration, traditional phase-leg which is composed of two power switches is replaced by the novel leg composed of one power switch and one diode. The annoying `shoot-through?? phenomenon is eliminated by using this novel configuration. Meanwhile, better efficiency and better performance brought by this novel configuration benefit the improvement of the compensation performance. Moreover, operation principle of the APF is analysed in detail; current control strategy and the voltage balance control strategy for the split-capacitor topology are studied as well. Finally, a prototype with the compensating capacity of 3 kVA is designed. Simulation and experimental results are shown to confirm the validity and feasibility of the novel aeronautical APF. View full abstract»

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  • Improved trench MOS barrier Schottky rectifier by dielectric engineering

    Publication Year: 2014 , Page(s): 325 - 329
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (504 KB)  

    An improved trench MOS barrier Schottky (TMBS) rectifier by dielectric engineering variable K TMBS (VK-TMBS) is proposed and studied by two-dimensional numerical simulations. The device shows increasing forward current density and reduction in specific on-resistance (Rsp), as compared with a regular TMBS rectifier. VK-TMBS attains a breakdown voltage of 140 V, which is larger than that of the original TMBS. The forward voltage drop of TMBS is 0.64 V at 180 A/cm2 , and that of VK-TMBS is 0.59 V. The Rsp of VK-TMBS is 26.7% smaller than that of the TMBS. The numerical simulation results indicate that the proposed device features high performance with an improved figure of merit. View full abstract»

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  • Design and analysis of operating strategies for a generalised voltage-source power supply based on internal model principle

    Publication Year: 2014 , Page(s): 330 - 339
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (936 KB)  

    This study presents a generalised voltage-source power supply to generate arbitrary shapes of voltage waveforms. The proposed voltage-source power supply can not only generate sinusoidal fundamental voltage waveforms, but also produce desired harmonic and asymmetrical voltage waveforms for applications of series active power filter, dynamic voltage regulator, uninterrupted power supply and programmable AC power source. The purpose of this study is to propose a novel operating strategy under synchronous coordinate frame based on internal model principle controllers, in such a way that it can provide more accurate tracking ability for generalised voltage references. Besides, the features of fast dynamic response, high stability and easy implementation are offered. The detailed design and analysis for the proposed strategy are given. An improved virtual resistor method is proposed to further improve the performance of the generalised voltage-source power supply. Both simulated and experimental results are given to verify the validity of the proposed approaches. View full abstract»

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  • Experimental verification of Hopf bifurcation in pulse-width modulated inverter fed cage induction motor drive system

    Publication Year: 2014 , Page(s): 340 - 349
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1257 KB)  

    Bifurcation theory deals with the change of qualitative behaviour in a parameter space of dynamical systems. This study investigates the bifurcation phenomenon of an industrial drive having typically constant speed requirement for which pulse-width modulated inverter fed cage induction motor (IM) is a good choice. The focus is on bifurcation analysis of the stator voltage controlled IM drive, with a particular emphasis on the dynamics and stability under variations of load torque and proportional integral controller gain. Extensive computer simulations are performed to capture the system??s dynamic behaviour and demarcate the bifurcation boundaries. Trajectory and Poincar?? section before and after the bifurcation are shown. The detailed mathematical model of the closed-loop system is derived and is used to analyse the observed bifurcation phenomena. The describing equations reveal that the system loses stability via supercritical Hopf bifurcation. Experimental results are also provided to confirm the theoretical analysis. View full abstract»

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  • Optimal selective harmonic elimination for cascaded H-bridge-based multilevel rectifiers

    Publication Year: 2014 , Page(s): 350 - 356
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (647 KB)  

    In medium-voltage medium- and high-power converters, it is of great importance to reach high-quality waveforms with low switching frequency. In active rectifiers, both converter??s ac-side harmonics and grid preexisting distortions affect the quality of the input current, which according to the existing standards is restricted from both the individual harmonics amplitude and total harmonic distortion point of view. The well known selective harmonic elimination pulse-width modulation technique is able to completely eliminate certain harmonics from the ac-side voltage of the converter, and as a result increases the quality of the input current. In this study, an optimal selective harmonic elimination control strategy is introduced for cascaded H-bridge (CHB) rectifiers. By fully manipulating the ac-side waveform of the rectifier, maximum number of harmonics is eliminated for a specific number of switching transitions. Moreover, this method can be easily extended for any number of H-bridge cells and it uses only one lookup table for the whole interval of modulation index. Also using an effective voltage balancing technique, dc-link voltages are balanced to the reference value and the rectifier does not encounter any difficulty under equal or nonequal loads conditions. Using this method, the size of the bulky line-side filters can be reduced which leads to lower overall cost of implementation. To prove the feasibility of the proposed scheme, simulation and experimental results for a seven-level CHB-based rectifier are reported. View full abstract»

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  • New concept on sinusoidal modulation for three-phase DC/AC converters: analysis and experiments

    Publication Year: 2014 , Page(s): 357 - 365
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1536 KB)  

    Various modulation schemes have already been developed for conventional three-phase buck-type converters such as sinusoidal pulse-width modulation and space vector modulation (SVM). However, SVM is not applicable to boost-type converters. This study proposes a new concept on sinusoidal modulation for both buck and boost-type three-phase DC??AC converters. A novel optimised modulation technique is introduced by using basic equations of conventional buck and boost. By solving the optimisation problem, pulse widths will be obtained for a given modulation index. The significant point is that the optimisation problem should not be solved for every modulation index because the answer of the optimisation problem obeys a certain pattern. Also, this method has a positive effect on reducing losses, especially in boost-converters. Analysis and simulations are first introduced for three-phase boost-converters, and then is extended to a buck converter. Furthermore, practical verification takes place on two implemented 1 kVA boost and buck-converters in order to confirm the proposed technique as well as theoretical analysis and simulations. The experiments and simulations both verify the suggested optimised modulation technique. View full abstract»

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  • Static performance and parasitic analysis of tapped-inductor converters

    Publication Year: 2014 , Page(s): 366 - 375
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (885 KB)  

    Tapped-inductor provides the property of wider voltage conversion range similar to an auto-transformer and can be integrated to a switched-mode power converter to enhance the power conversion efficiency. Its low component count has attracted applications with extreme voltage conversion ratios. Circuit family is presented and a general tapping concept for diode, transistor or both has been described. Its boost converter version is used as an example for the study. Detailed comparisons between tapped-inductor boost and conventional boost are carried out, which include the comparison of voltage gain, component stress and efficiency with the presence of the parasitic components. Experimental results present solid verification of the analysis of performance of tapped-inductor boost converter under extreme conversion ratios. The proposed study has introduced formulations for both transistor and diode tapping and can be extended to other tapped-inductor DC??DC converters as a family of circuits, and thus provides an understanding of the effect of the parasitic components that affect the efficiency under extreme conversion ratio. View full abstract»

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  • Field programmable gate array implementation of space-vector pulse-width modulation technique for five-phase voltage source inverter

    Publication Year: 2014 , Page(s): 376 - 389
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1745 KB)  

    This study analyses a field programmable gate array (FPGA) implementation of space-vector pulse-width modulation (SVPWM) technique for five-phase voltage source inverter (VSI). The five-phase VSIs are dominantly used to supply the fivephase drives that are used for high-power applications. It is necessary to develop an appropriate SVPWM technique for the inverters to provide the required output voltages to five-phase induction motor load. In the proposed work, SVPWM algorithm is described in high-speed integrated circuit hardware description language coding and implemented in an XILINX XC3SD1800A FPGA processor. The relationship between the SVPWM technique for medium, large and combinations of large and medium space vectors for five-phase VSI is analysed. The selection of active space vector and zero vectors is discussed and the possibilities of FPGA implementations are explored. The experimental results with 1 hp five-phase induction motor drive are presented for the different SVPWM techniques. The best SVPWM scheme is identified based on the output voltage and total harmonic distortion. View full abstract»

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  • Interleaved non-isolated high step-up DC/DC converter based on the diode-capacitor multiplier

    Publication Year: 2014 , Page(s): 390 - 397
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (715 KB)  

    A kind of interleaved non-isolated high step-up DC/DC converter is presented in this study. The converter consists of two basic Boost cells and some diode-capacitor multiplier (DCM) cells as needed. Because of the DCM cells, the voltage conversion ratio is enlarged and the extreme large duty ratio can be avoided in the high step-up applications. Moreover, the voltage stress of all the power devices is greatly lower than the output voltage. As a result, lower-voltage-rated power devices can be employed, and higher efficiency can be expected. Since the two basic Boost cells are controlled by the interleaving method, which means the phase difference between the two pulse width moderlation (PWM) signals is 180?? and the input current is the sums of the two inductor currents, the input current ripple is decreased and the size of the input filter could be reduced, which make it a suitable choice in the photovoltaic power generation system and hybrid electric vehicles, etc. Finally, the experimental results from a 300 W, 30-400 V laboratory prototype are presented to validate the effectiveness of the proposed converter. View full abstract»

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  • Switching strategy for six switches forced commutated cycloconverter with several advantages

    Publication Year: 2014 , Page(s): 398 - 405
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (868 KB)  

    Forced commutated cycloconverters (FCCs) are very popular topics today which can generate variable frequency and variable voltage in output. These converters include six switches in each phase where operation of these converters depends on switching strategy. This study describes a novel switching strategy for six switches FCC where this strategy transfers seven input voltages to FCC output. In each switching period, among seven input voltages, there are only two input voltages which surround reference output voltage. Hence, the proposed strategy makes these two input voltages around reference voltage transfer to FCC output in each switching period. As a result, average value of FCC output voltage is the same as reference voltage. Main benefits of this switching strategy are minimisation of total harmonic distortion, reduction of dv/dt stresses on the load, lower harmonic components, high-voltage modulation index and performance in unbalance or non-sinusoidal input voltage condition. The operation and performance of the proposed switching strategy has been verified by the simulation and measurement results which were carried out for three-phase to single-phase converter. The proposed switching strategy serves as the conceptual platform for extending the principles to other FCC topologies. View full abstract»

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  • Parallel operation of photovoltaic power conditioning system modules for large-scale photovoltaic power generation

    Publication Year: 2014 , Page(s): 406 - 417
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1097 KB)  

    In this study, parallel operation of photovoltaic (PV) power conditioning system (PCS) modules for large-scale PV power generation is proposed. This system consists of PCS modules that are connected in parallel and share the dc-link voltage. PCS modules can be easily connected in parallel for high-power extension and independent control of the PCS module is achieved. Since this system does not use communication lines among the PCS modules, sensing signal noise and the mutual interference can be neglected. In addition, the number of PCS modules operating simultaneously can be controlled in accordance with the irradiance. Thus, system efficiency can be maximised and PCS module life time is extended. Further, the system has high availability since it has N + 1 redundancy that is achieved by increasing the power capacity of PCS modules through the use of an additional PCS module. A prototype of the proposed system is implemented at a rated power of 500 kW. Experimental results for parallel operation of PCS modules show the feasibility of the proposed control. View full abstract»

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  • Harmonic power compensation capacity of shunt active power filter and its relationship with design parameters

    Publication Year: 2014 , Page(s): 418 - 430
    Cited by:  Papers (2)
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1004 KB)  

    In this study, the equation for the reactive and harmonic power compensation of a shunt active power filter (APF) system has been derived by studying the power exchange mechanism and power tetrahedron phasor diagram. The switching dynamics of a voltage source inverter (VSI)-based three-phase, three-wire (three-leg /half-bridge) shunt APF system with hysteresis band current control has been studied and verified by simulation. The relation between the design parameters and their effects on the active losses has also been identified. Detailed calculation and extensive simulation have been performed for a three-phase, three-wire shunt APF implemented in a 400VL-L distribution system, as an example, to study the effects of design parameter selection and their role in active power loss calculation. Simulated and calculated results are presented for the important design parameters for different switching frequencies together with their associated losses and kVA ratings. The procedure can be followed to design the parameters for other topologies, such as three-phase, four-wire or single-phase systems. View full abstract»

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  • Fractional-order repetitive control of programmable AC power sources

    Publication Year: 2014 , Page(s): 431 - 438
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (667 KB)  

    Programmable AC power sources that provide variable-frequency and variable-amplitude output voltages are widely used in automatic testing equipment and bench top applications. Under various load conditions, a high-performance programmable AC power source not only can generate very clean sinusoidal output voltages, but also to accurately synthesise specified harmonic distorted wave-shapes. Digital repetitive control (RC) can achieve zero steady-state error tracking of any periodic signal with known integer period, but usually fails to provide precise tracking of variable-frequency periodical waveform with fractional period. In this study, a frequency adaptive fractional-order RC (FORC) strategy at fixed sampling rate is proposed to track or eliminate any periodic signals with variable frequency, where a Lagrange interpolation-based fractional delay filter is used to approximate the factional delay items in RC. The proposed FORC that offers fast on-line tuning of the fractional delay and the fast update of the coefficients, provide a simple but high-performance real-time control approach to dealing with variable-frequency variable-magnitude periodic signals. A case study of FORC-based programmable AC power source is conducted. Experimental results are provided to show the effectiveness of the proposed FORC strategy. It can be widely used in extensive applications. View full abstract»

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  • Reduced DC voltage source flying capacitor multicell multilevel inverter: analysis and implementation

    Publication Year: 2014 , Page(s): 439 - 450
    Cited by:  Papers (1)
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1777 KB)  

    Voltage source multicell multilevel converters (VSMMCs) have been extensively exploited in medium-voltage highpower fed industrial applications. One of the typical breeds of the VSMMCs is flying-capacitor multicell converter (FCMC). This study presents an improved configuration for FCMCs, accompanied by its analysis, modelling and implementation. The main advantage of the proposed converter, in comparison with the conventional one, is that the number and voltage rating of the required dc voltage sources are halved in the improved topology which results in reducing the cost, size, installation area and weight of the FCMCs effectively. This amelioration is attained by adding four power switches to the conventional topology of an FCMC without making any amendments to the number and voltage rating of high-frequency power-switches and flying capacitors (FCs). The proposed switching and control methodology for the adopted FCMC is based on the phase-shifted carrier pulse width modulation technique with applying some amendments; therefore the natural balancing phenomenon of the FC voltages, one of the critical advantages of the FCMCs, is preserved in the proposed VSMMC. Experimental measurements taken from the 3-cell-four-level and 4-cell-five-level laboratory prototype systems of the proposed converter are presented in order to validate and corroborate the effectiveness and advantages of the proposed topology, its switching and suggested control strategy. Furthermore, experimental studies are accomplished on an 8-cell-nine-level prototype system of the proposed FCMC to peruse its feasibility and viability for higher number of cells and voltage levels. In addition, comparison of the proposed converter with the other types of multilevel converters is carried out to underline the advantages of the proposed structure profoundly. View full abstract»

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  • Single-phase transformerless bi-directional inverter with high efficiency and low leakage current

    Publication Year: 2014 , Page(s): 451 - 458
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (625 KB)  

    This study proposes a high efficient bi-directional inverter for a photovoltaic (PV) systemintegrated with an energy storage system. The proposed bi-directional inverter controls the bi-directional power flow and satisfies the power requirement between the grid and the dc sources. The proposed bi-directional inverter achieves high efficiency by employing a transformerless structure and by minimising the power losses. The inverter structure can suppress the leakage current, which is considered to be one of the most important design parameters in a transformerless PV system. The efficiency and leakage current of the proposed bi-directional inverter are analysed. Furthermore, its bi-directional operation principles and control method are described. Finally, a 3-kW prototype is implemented to confirm the theoretical analysis and the validity of the proposed bi-directional inverter. View full abstract»

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  • Developed cascaded multilevel inverter topology to minimise the number of circuit devices and voltage stresses of switches

    Publication Year: 2014 , Page(s): 459 - 466
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1006 KB)  

    In this study, a novel structure for cascade multilevel inverter is presented. The proposed inverter can generate all possible DC voltage levels with the value of positive and negative. The proposed structure results in reduction of switches number, relevant gate driver circuits and also the installation area and inverter cost. The suggested inverter can be used as symmetric and asymmetric structures. Comparing the peak inverse voltage and losses of the proposed inverter with conventional multilevel inverters show the superiority of the proposed converter. The operation and good performance of the proposed multilevel inverter have been verified by the simulation results of a single-phase nine-level symmetric and 17-level asymmetric multilevel inverter and experimental results of a nine-level and 17-level inverters. Simulation and experimental results confirmed the validity and effectiveness performance of the proposed inverter. View full abstract»

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IET Power Electronics brings together five principal power electronics themes including: applications of power semiconductor technology; circuits; devices; techniques; and performance management.

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