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Power Electronics, IEEE Transactions on

Issue 1 • Date Jan. 2012

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Displaying Results 1 - 25 of 52
  • [Front cover]

    Publication Year: 2012 , Page(s): C1
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  • IEEE Transactions on Power Electronics publication information

    Publication Year: 2012 , Page(s): C2
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  • Table of contents

    Publication Year: 2012 , Page(s): 1 - 2
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  • Editorial for IEEE Transactions on Power Electronics, January 2012

    Publication Year: 2012 , Page(s): 3 - 4
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  • Efficient and Linear Power Amplifier Based on Envelope Elimination and Restoration

    Publication Year: 2012 , Page(s): 5 - 9
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (497 KB) |  | HTML iconHTML  

    This letter describes a power amplifier (PA) with high linearity based on the envelope elimination and restoration (EER) technique. PAs based on this technique are composed of a highly efficient nonlinear PA (class E) that performs phase modulation and a wide bandwidth envelope amplifier that supplies the nonlinear PA and has to inject the envelope through power supply modulation. The design of the envelope amplifier is a complicated task due to the tradeoff between demanded high efficiency and very wide bandwidth. In order to obtain a reasonably high efficiency and very wide bandwidth, a solution based on the multilevel converter in series with a linear regulator is proposed. It provides up to 100 W of peak power and tracks sine waves up to 2 MHz. The class E amplifier has been optimized for high-efficiency (near 85%) and high-frequency (120 MHz) operation. The experimental results presented in this letter validate the proposed solutions for the envelope and phase amplifier, demonstrate that the implemented EER PA can handle up to 100 W of peak power, and highlight its high linearity (around 40 dB of attenuation of the intermodulation products) and high efficiency (up to 25% less power losses than an ideal class B amplifier). View full abstract»

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  • A Stand-Alone Dual Stator-Winding Induction Generator Variable Frequency AC Power System

    Publication Year: 2012 , Page(s): 10 - 13
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (550 KB) |  | HTML iconHTML  

    This letter proposes a variable frequency ac (VFAC) stand-alone power system based on the dual stator-winding induction generator (DWIG) with the static excitation controller (SEC). A slip frequency control strategy using the information of the output voltage and the output power is employed to guarantee that the system has a desirable static and dynamic performance in a wide speed range. The experimental results on a prototype verify the principle and performance of the proposed control method. View full abstract»

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  • A Novel DC Capacitor Voltage Balance Control Method for Cascade Multilevel STATCOM

    Publication Year: 2012 , Page(s): 14 - 27
    Cited by:  Papers (17)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1868 KB) |  | HTML iconHTML  

    This paper presents a novel dc capacitor voltage balance control method for cascade multilevel static synchronous compensator (STATCOM) and a general analytical method for balance control strategy. Considering that the imbalance of dc capacitor voltage is caused by the inconsistency of active power absorbed and consumed by chain, a balance control strategy based on active voltage vector superposition is proposed, in which an active voltage component is superposed to chain's output voltage to change its absorbed active power. A general analytical method based on vector analysis is also presented, by which the performance of balance control strategy can be analyzed, including stability and regulation capacity. To find out the most appropriate balance control strategy, a comparison still based on vector analysis among the proposed and other two commonly used methods is provided, from which it can be known that the proposed balance control strategy has the advantage of good stability and strong regulation capacity, and simulations are performed to prove it. The effectiveness of proposed control scheme has been verified by experimental results based on a three-phase 36-chain cascade multilevel STATCOM laboratory prototype. View full abstract»

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  • High-Power Modular Multilevel Converters With SiC JFETs

    Publication Year: 2012 , Page(s): 28 - 36
    Cited by:  Papers (42)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (861 KB) |  | HTML iconHTML  

    This paper studies the possibility of building a modular multilevel converter (M2C) using silicon carbide (SiC) switches. The main focus is on a theoretical investigation of the conduction losses of such a converter and a comparison to a corresponding converter with silicon-insulated gate bipolar transistors. Both SiC BJTs and JFETs are considered and compared in order to choose the most suitable technology. One of the submodules of a down-scaled 3 kVA prototype M2C is replaced with a submodule with SiC JFETs without antiparallel diodes. It is shown that the diodeless operation is possible with the JFETs conducting in the negative direction, leaving the possibility to use the body diode during the switching transients. Experimental waveforms for the SiC submodule verify the feasibility during normal steady-state operation. The loss estimation shows that a 300 MW M2C for high-voltage direct current transmission would potentially have an efficiency of approximately 99.8% if equipped with future 3.3 kV 1.2 kA SiC JFETs. View full abstract»

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  • High-Efficiency High-Reliability Pulsed Power Converters for Industrial Processes

    Publication Year: 2012 , Page(s): 37 - 45
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1346 KB) |  | HTML iconHTML  

    This paper considers monitoring of semiconductor thermal cycling in high-power resonant converters. For the experiments, a dedicated single-phase resonant converter rated at 1 kV, 250 A (250-kW peak power, duty ratio 10%, 25-kW average power, AND pulse length 1 ms) was been developed. This converter represents one phase of a multiphase resonant power supply designed for long-pulse modulation (typically 1-2 ms) when equipped with a suitable output transformer. Pulsed operation is obtained by direct modulation of the high-frequency power supply. The main aim of the study reported here is to develop a methodology to assess performance and reliability issues related to the use of standard commercially available power switch technology, relying on a physics-based multichip insulated gate bipolar transistor (IGBT) structure model, and to experimentally monitor the chip temperature using high-speed thermal imaging, during the pulse, to identify any limitations of the proposed modulator technology. First, an overview of the converter, including its nominal electrical design, is provided. Optimization of the turn-OFF snubber capacitance is performed through a series of experiments, employing calorimetrically measured losses, to determine a value, which minimizes the overall power losses. Accurate calorimetric measurements of the switching losses and infrared measurements of the IGBT surface temperatures during transient operation are presented. Simulations including multichip structures, experimental results, and high-quality chip thermal images are provided to validate the effectiveness of the proposed approaches. View full abstract»

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  • Generalized Analysis of a Multistate Switching Cells-Based Single-Phase Multilevel PFC Rectifier

    Publication Year: 2012 , Page(s): 46 - 56
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1309 KB) |  | HTML iconHTML  

    The single-phase multilevel power-factor correction rectifier employing multistate switching cells is analyzed regarding different operational aspects. The generalization of the number of switching states is performed in order to clarify issues such as the input current ripple, the output currents rms values, power semiconductor stresses, and others. A discussion on the optimal number of switching states is carried out, based on the generated models. In this context, this work is a first step aiming in the efficiency-based optimization of the concept. View full abstract»

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  • Steady-State Analysis of Interaction Between Harmonic Components of Arm and Line Quantities of Modular Multilevel Converters

    Publication Year: 2012 , Page(s): 57 - 68
    Cited by:  Papers (66)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (506 KB) |  | HTML iconHTML  

    The fundamental frequency component in the arm currents of a modular multilevel converter is a necessity for the operation of the converter, as is the connection and bypassing of the submodules. Inevitably, this will cause alternating components in the capacitor voltages. This paper investigates how the arm currents and capacitor voltages interact when the submodules are connected and bypassed in a sinusoidal manner. Equations that describe the circulating current that is caused by the variations in the total inserted voltage are derived. Resonant frequencies are identified and the resonant behaviour is verified by experimental results. It is also found that the effective values of the arm resistance and submodule capacitances can be extracted from the measurements by least square fitting of the analytical expressions to the measured values. Finally, the analytical expression for the arm currents is verified by experimental results. View full abstract»

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  • A Hybrid Active Filter for a Three-Phase 12-Pulse Diode Rectifier Used as the Front End of a Medium-Voltage Motor Drive

    Publication Year: 2012 , Page(s): 69 - 77
    Cited by:  Papers (25)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1043 KB) |  | HTML iconHTML  

    This paper describes a hybrid active filter intended for mitigating the line-side harmonic currents of a three-phase 12-pulse diode rectifier used as the front end of a medium-voltage high-power motor drive. This hybrid filter is characterized by series connection of a simple LC filter and a small-rated active filter. This circuit configuration brings low cost, small size, and light weight to the hybrid filter. A three-phase experimental system rated at 400 V and 15 kW is designed, constructed, and tested, which is a downscaled model of the medium-voltage motor drive system. In this experiment, the LC filter is tuned to the 11th-harmonic frequency, and the active filter is based on a three-level neutral-point-clamped pulsewidth modulation converter (NPC PWM) with a dc capacitor voltage as low as 28 V. This hybrid filter is connected on either first or fourth winding of a line-frequency transformer with a first Δ-winding voltage of 400 V in the primary, and a second Δ-winding voltage of 220 V, a third Y-winding voltage of 220 V, and a fourth Δ-winding voltage of 400 V in the secondary. Experimental results show that the hybrid filter performs satisfactory filtering in a range from no-load to full-load conditions. View full abstract»

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  • Addressing DC Component in PLL and Notch Filter Algorithms

    Publication Year: 2012 , Page(s): 78 - 86
    Cited by:  Papers (31)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (944 KB) |  | HTML iconHTML  

    This paper presents a method for addressing the dc component in the input signal of the phase-locked loop (PLL) and notch filter algorithms applied to filtering and synchronization applications. The dc component may be intrinsically present in the input signal or may be generated due to temporary system faults or due to the structure and limitations of the measurement/conversion processes. Such a component creates low-frequency oscillations in the loop that cannot be removed using filters because such filters will significantly degrade the dynamic response of the system. The proposed method is based on adding a new loop inside the PLL structure. It is structurally simple and, unlike an existing method discussed in this paper, does not compromise the high-frequency filtering level of the concerned algorithm. The method is formulated for three-phase and single-phase systems, its design aspects are discussed, and simulations/experimental results are presented. View full abstract»

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  • Robust Line-Voltage Sensorless Control and Synchronization of LCL -Filtered Distributed Generation Inverters for High Power Quality Grid Connection

    Publication Year: 2012 , Page(s): 87 - 98
    Cited by:  Papers (27)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1697 KB) |  | HTML iconHTML  

    This paper presents a robust control scheme for high power quality grid connection of inductor-capacitor-inductor (LCL)-filtered distributed generation (DG) inverters. The presence of the LCL filter complicates the dynamics of the inverter control system, particularly when the uncertain nature of the grid background distortion and system parameters is considered. The proposed scheme addresses such practical difficulties by providing: 1) robust and simple active damping control performance under grid and filter parameter variation; 2) suppression of grid-induced distortion without a-priori knowledge of the grid background distortion and unbalance via real-time generation of the frequency modes and disturbances that should be eliminated from the closed-loop current control system; 3) robust deadbeat digital control performance that maximizes the dynamic performance of the converter; and 4) robustness against interaction dynamics between active damping and current tracking controllers. Furthermore, the proposed control scheme facilitates line-voltage sensorless current control and grid-synchronization performance, which enhances the reliability and cost measures of the DG interface. Theoretical analysis and comparative evaluation results are presented to demonstrate the effectiveness of the proposed control scheme. View full abstract»

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  • A Stationary Reference Frame Grid Synchronization System for Three-Phase Grid-Connected Power Converters Under Adverse Grid Conditions

    Publication Year: 2012 , Page(s): 99 - 112
    Cited by:  Papers (58)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2670 KB) |  | HTML iconHTML  

    Grid synchronization algorithms are of great importance in the control of grid-connected power converters, as fast and accurate detection of the grid voltage parameters is crucial in order to implement stable control strategies under generic grid conditions. This paper presents a new grid synchronization method for three-phase three-wire networks, namely dual second-order generalized integrator (SOGI) frequency-locked loop. The method is based on two adaptive filters, implemented by using a SOGI on the stationary αβ reference frame, and it is able to perform an excellent estimation of the instantaneous symmetrical components of the grid voltage under unbalanced and distorted grid conditions. This paper analyzes the performance of the proposed synchronization method including different design issues. Moreover, the behavior of the method for synchronizing with highly unbalanced grid is proven by means of simulation and experimental results, demonstrating its excellent performance. View full abstract»

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  • Toward a Generic Torque and Reactive Power Controller for Doubly Fed Machines

    Publication Year: 2012 , Page(s): 113 - 121
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1201 KB) |  | HTML iconHTML  

    A novel shaft-position sensorless algorithm for decoupled control of torque and reactive power (TRPC) of doubly fed machines, such as the classical wound-rotor induction machine (DFIM) and the emerging brushless reluctance machine (BDFRM), has been discussed and experimentally verified in this paper. The underlying control concept is derived from first principles of magnetization and torque production in the machines. For control purposes, only the grid-connected winding measurements and rough knowledge of its resistance value are required. Such a weak parameter dependence makes the TRPC inherently robust, structurally simple, and fast to execute even on low-cost DSPs. A variety of applications are possible including drive and generator systems with limited variable speed ranges (e.g., large pumps and wind turbines), where cost savings of using partially rated power electronics are significant. Two custom-designed and built BDFRM prototypes have served as case studies to evaluate the controller performance by computer simulations and through laboratory experiments. View full abstract»

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  • A New Battery/UltraCapacitor Hybrid Energy Storage System for Electric, Hybrid, and Plug-In Hybrid Electric Vehicles

    Publication Year: 2012 , Page(s): 122 - 132
    Cited by:  Papers (70)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1320 KB) |  | HTML iconHTML  

    In this paper, a new battery/ultracapacitor hybrid energy storage system (HESS) is proposed for electric drive vehicles including electric, hybrid electric, and plug-in hybrid electric vehicles. Compared to the conventional HESS design, which uses a larger dc/dc converter to interface between the ultracapacitor and the battery/dc link to satisfy the real-time peak power demands, the proposed design uses a much smaller dc/dc converter working as a controlled energy pump to maintain the voltage of the ultracapacitor at a value higher than the battery voltage for the most city driving conditions. The battery will only provide power directly when the ultracapacitor voltage drops below the battery voltage. Therefore, a relatively constant load profile is created for the battery. In addition, the battery is not used to directly harvest energy from the regenerative braking; thus, the battery is isolated from frequent charges, which will increase the life of the battery. Simulation and experimental results are presented to verify the proposed system. View full abstract»

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  • Interleaved High Step-Up Converter With Winding-Cross-Coupled Inductors and Voltage Multiplier Cells

    Publication Year: 2012 , Page(s): 133 - 143
    Cited by:  Papers (19)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (714 KB) |  | HTML iconHTML  

    The concept of winding-cross-coupled inductors (WCCIs) and voltage multiplier cells is integrated to derive a novel interleaved high step-up converter in this paper. The voltage gain is extended and the switch voltage stress is reduced by the WCCIs and the voltage multiplier cells in the presented circuit, which minimizes the peak current ripple of the power devices and makes low-voltage MOSFETs with high performance available in high step-up and high output voltage applications. Moreover, the output diode reverse-recovery problem is alleviated by the leakage inductance of the WCCIs, which reduces the reverse-recovery losses. Zero current switching (ZCS) turn-on is realized for the power switches to reduce the switching losses. Furthermore, the voltage spikes on the MOSFETs are clamped and the leakage energy is recycled by the voltage multiplier cells, when the switch turns off. A 1 kW prototype with 35-45 V input and 380 V output operating at 50 kHz switching frequency is built and tested to verify the significant improvements of the proposed converter. View full abstract»

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  • Analysis and Design of a Zero-Current Switching Forward Converter With Simple Auxiliary Circuit

    Publication Year: 2012 , Page(s): 144 - 150
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (696 KB) |  | HTML iconHTML  

    In this paper, a new zero-current switching pulse width modulation forward converter is introduced using a new switching algorithm for the auxiliary circuit. In the proposed converter, transformer core is reset through a resonance, and thus, reset winding is not required which is the main advantage of this converter over existing zero-current switching forward converters. The simple auxiliary circuit of this converter is just composed of an auxiliary switch and a capacitor that provides zero-current switching for the main switch and also resets the transformer core. Furthermore, the proposed auxiliary circuit uses the leakage inductance of the transformer for the resonant inductor and does not require any additional inductor which is another advantage of the proposed converter over conventional zero-current switching forward converters. Also, the auxiliary switch is soft switched. The proposed converter is analyzed and design procedure of the auxiliary circuit is discussed. The presented experimental results confirm the theoretical analysis. View full abstract»

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  • Reducing Storage Capacitor of a DCM Boost PFC Converter

    Publication Year: 2012 , Page(s): 151 - 160
    Cited by:  Papers (12)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1050 KB) |  | HTML iconHTML  

    The discontinuous current mode boost power factor correction (PFC) converter automatically achieves PFC when the duty cycle is kept constant in a line cycle; however, there is large third harmonic in the input current, and the third harmonic has the initial phase of π in respect of the fundamental component. Therefore, the input power factor is low, and a large storage capacitor is needed. Injecting appropriate third harmonic with initial phase of zero into the input current could reduce the storage capacitor. This paper proposes the variable duty cycle control to inject the required third harmonic into the input current to meet the requirement of IEC 61000-3-2 Class D or Energy Star. A method of fitting the duty cycle is further proposed for simplifying the circuit implementation. The experimental results from a 120-W universal input prototype are given to verify the effectiveness of the proposed method. View full abstract»

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  • Analysis and Design of a Zero-Voltage-Switching and Zero-Current-Switching Interleaved Boost Converter

    Publication Year: 2012 , Page(s): 161 - 173
    Cited by:  Papers (15)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2188 KB) |  | HTML iconHTML  

    A novel interleaved boost converter with zero-voltage switching (ZVS) and zero-current switching (ZCS) characteristics is proposed in this paper. By using the interleaved approach, this topology not only decreases the current stress of the main circuit device but also reduces the ripple of the input current and output voltage. Moreover, by establishing the common soft-switching module, the soft-switching interleaved converter can greatly reduce the size and cost. The main switches can achieve the characteristics of ZVS and ZCS simultaneously to reduce the switching loss and improve the efficiency with a wide range of load. This topology has two operational conditions depending on the situation of the duty cycle. A driving circuit is designed for the proposed topology to determine the two conditions automatically. The operational principle, theoretical analysis, and design method of the proposed converter are presented. Finally, simulations and experimental results are used to verify the feasibility and exactness of the proposed converter. View full abstract»

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  • Closed Form Solution for Minimum Conduction Loss Modulation of DAB Converters

    Publication Year: 2012 , Page(s): 174 - 188
    Cited by:  Papers (32)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2653 KB) |  | HTML iconHTML  

    An optimal modulation scheme that enables minimum conduction and copper losses is presented for a bidirectional dual active bridge (DAB) dc-dc converter. The considered converter system is employed for an automotive application and comprises of a high voltage (HV) port with port voltage V1, 240V ≤ V1 ≤ 450 V, and a low voltage (LV) port with port voltage V2, 11 V ≤ V2 ≤ 16 V; the rated output power is 2 kW. The closed-form expressions for the optimal control parameters are derived and implementation details are presented in order to facilitate the direct application to a given DAB converter. The paper further details the properties of the presented modulation scheme with respect to switching losses. Experimental results confirm a considerable increase of the converter efficiency achieved with the proposed optimal modulation scheme, compared to the efficiency obtained with conventional phase shift modulation. The efficiency increase is most distinct at V1=450V and V2 = 11V with an increase from 78.6% to 90.6% at 1 kW output power and from 85.9% to 90.7% at rated output power as compared to conventional phase shift modulation. View full abstract»

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  • High-Frequency Resonant SEPIC Converter With Wide Input and Output Voltage Ranges

    Publication Year: 2012 , Page(s): 189 - 200
    Cited by:  Papers (29)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1244 KB) |  | HTML iconHTML  

    This paper presents a resonant single-ended-primary-inductor-converter (SEPIC) converter and control method suitable for high frequency (HF) and very high frequency (VHF) dc-dc power conversion. The proposed design provides high efficiency over a wide input and output voltage range, up-and-down voltage conversion, small size, and excellent transient performance. In addition, a resonant gate drive scheme is presented that provides rapid startup and low-loss at HF and VHF frequencies. The converter regulates the output using an ON-OFF control scheme modulating at a fixed frequency (170 kHz). This control method enables fast transient response and efficient light-load operation while providing controlled spectral characteristics of the input and output waveforms. A hysteretic override technique is also introduced which enables the converter to reject load disturbances with a bandwidth much greater than the modulation frequency, limiting output voltage disturbances to within a fixed value. An experimental prototype has been built and evaluated. The prototype converter, built with two commercial vertical MOSFETs, operates at a fixed switching frequency of 20 MHz, with an input voltage range of 3.6-7.2 V, an output voltage range of 3-9 V, and an output power rating of up to 3 W. The converter achieves higher than 80% efficiency across the entire input voltage range at nominal output voltage and maintains good efficiency across the whole operating range. View full abstract»

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  • A Modified Single-Phase Quasi-Z-Source AC–AC Converter

    Publication Year: 2012 , Page(s): 201 - 210
    Cited by:  Papers (11)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1567 KB) |  | HTML iconHTML  

    A modified single-phase quasi-Z-source ac-ac converter is proposed in this paper. The proposed converter has the main features in that the output voltage can be bucked or boosted and be both in-phase and out-of-phase with the input voltage. The input voltage and output voltage share the same ground, the size of a converter is reduced, and it operates in a continuous current mode. A safe-commutation strategy for the modified single-phase quasi-Z-source ac-ac converter is used instead of a snubber circuit. The operating principles and a steady-state analysis are presented. A laboratory prototype, tested using a resistive load, a passive load, and a nonlinear load, was constructed that used an input voltage of 70 Vrms /60 Hz in order to verify the performance of the modified single-phase quasi-Z-source ac-ac converter. The experimental results verified that the converter has a lower input current total harmonic distortion, a higher input power factor, and a higher efficiency in comparison to a conventional single-phase Z-source ac-ac converter. In addition, the experimental results show that the use of the safe-commutation strategy is a significant improvement, as it makes it possible to avoid voltage spikes on the switches. View full abstract»

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  • Feed-Forward Compensator of Operating Frequency for APWM HB Flyback Converter

    Publication Year: 2012 , Page(s): 211 - 223
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1049 KB) |  | HTML iconHTML  

    A feed-forward frequency compensator for an asymmetrical pulsewidth modulated (APWM) half-bridge (HB) flyback converter is proposed to increase its power conversion efficiency. Under a variable input voltage, the APWM HB flyback converter cannot be satisfied with the zero-current switching (ZCS) condition of output rectifiers because the variation of the turn-ON duration of main switches, which regulate the output voltage, induces their improper turn-OFF duration. This means that the resonance of a primary current during the turn-OFF of the switches is out of the ZCS operation of the output rectifiers. To avoid this improper operation, the resonant network should be designed with a marginal turn-OFF duration that guarantees the ZCS. However, this makes the converter operate with poor efficiency because of increasing conduction losses. The proposed feed-forward frequency compensator can properly change the converter's operating frequency to reduce the conduction losses according to the variation of the input voltage satisfying the ZCS condition of the output rectifiers. Operation principles, steady-state analysis, and soft-switching conditions are analyzed to derive the frequency compensation algorithm of the APWM HB flyback converter. Experimental results using a 240-W prototype converter show that the proposed compensation algorithm can improve the power conversion efficiency of the APWM HB flyback converter under the input-voltage variation. View full abstract»

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Aims & Scope

IEEE Transactions on Power Electronics covers fundamental technologies used in the control and conversion of electric power.

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