一种基于全波平衡电抗器的双反星形12脉波整流器

为了有效抑制常规双反星形整流器的输入电流谐波和输出电压脉动,提出一种基于全波平衡电抗器的双反星形12脉波整流器。所提出的12脉波整流器由常规的双反星形整流器和全波平衡电抗器组成。全波平衡电抗器中含有带副边绕组的平衡电抗器和辅助单相全波整流器,辅助单相全波整流器通过从平衡电抗器的副边绕组提取方波电流来增加2个三相半波整流桥的输出电流和电压模态,然后依据交直流两侧电流和直流侧电压的关系,将双反星形整流器的脉波数从6倍增到12,显著抑制了输入电流谐波和输出电压脉动。因流过辅助单相全波整流器的电流仅为负载电流的6.69%,相较于现有基于抽头平衡电抗器的脉波倍增方法,所提方法除具备电路结构简单可靠、易于实现和成本低廉等优点外,还具有更小的附加导通损耗,更适用于低压大功率工业场合。研制了一台功率为1.1 kW的实验样机,验证了理论分析的正确性和该方法的有效性。     

High input impedance voltage‐mode first‐order all‐pass sections

This paper proposes six new first‐order voltage‐mode all‐pass sections (VM‐APSs) based on three general topologies. Each circuit uses two differential voltage current conveyors and three grounded passive components. All the circuits possess high input impedance and easy control of pole frequency either by a simple matching of resistors (two equal‐valued resistors) for the three canonical circuits or by a single resistor for three non‐canonical circuits. PSPICE simulation results using real device 0.5µ CMOS parameters are given to validate the proposed circuits. Copyright © 2007 John Wiley & Sons, Ltd.     

A new bridgeless buck PFC rectifier

In this study, a new bridgeless buck power factor correction (PFC) rectifier is presented. The proposed buck PFC rectifier is designed to operate in the discontinuous conduction mode (DCM). Because of the DCM operation, the control scheme of the proposed buck PFC rectifier is simple and easy, and the reverse recovery problem of the diodes can be alleviated. Because the input current follows the input voltage naturally, the current loop circuit is not required. Thus, only the traditional voltage‐mode control is employed to sense the output voltage, and a suitable control effort for the proposed buck PFC rectifier is generated to drive the power switches. Consequently, the output voltage of the proposed buck PFC rectifier can be kept at a desired value. Finally, the mathematical deductions and experimental results are provided to verify the effectiveness of the proposed bridgeless buck PFC rectifier. Copyright © 2016 John Wiley & Sons, Ltd.     

Voltage mode and current mode Tow Thomas bi‐quadratic filters using inverting CCII

A voltage mode Tow Thomas bi‐quadratic filter using the inverting second‐generation current conveyor (ICCII) is given. The filter has high input impedance, employs two grounded capacitors, and has independent control on Q, independent control on the band‐pass and low‐pass response gain. Three alternative current mode filters are generated from the voltage mode circuit. The three circuits have zero input impedance, employ grounded capacitors and have independent control on Q. Two of the circuits have also all resistors grounded and the other uses only ICCII?and has only one floating resistor. Copyright © 2007 John Wiley & Sons, Ltd.     

Current waveform control of a high‐power‐factor rectifier circuit for harmonic suppression of voltage and current in a distribution system

This paper presents the input current waveform control of the rectifier circuit which realizes simultaneously the high input power factor and the harmonics suppression of the receiving‐end voltage and the source current under the distorted receiving‐end voltage. The proposed input current waveform includes the harmonic components which are in phase with the receiving‐end voltage harmonics. The control parameter in the proposed waveform is designed by examining the characteristics of both the harmonic suppression effect in the distribution system and the input power factor of the rectifier circuit. The effectiveness of the proposed current waveform has been confirmed experimentally. © 2002 Wiley Periodicals, Inc. Electr Eng Jpn, 140(4): 62–71, 2002; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10046     

Realizations of fully differential voltage second generation current conveyor with an application

Three novel CMOS realizations for the fully differential voltage second‐generation inverting current conveyor (FDVCCII‐) are proposed in this paper. The first realization has a limited input range, and the other two realizations have a rail to rail input range and show excellent features in linearity and bandwidth. As an application to the FDVCCII‐, a floating gyrator is proposed. A floating inductor is realized using the floating gyrator and it is used in realizing a second‐order low‐pass filter, which is simulated and compared with the ideal result. All circuits are simulated with SPICE using CMOS 0.35µm technology and supply voltages ±1.5V to verify the theoretical results. Copyright © 2008 John Wiley & Sons, Ltd.     

Analysis and implementation of a soft switching DC/DC converter with three asymmetric PWM circuits

This paper presents a soft switching converter with three buck‐type active clamp circuits (or asymmetric half‐bridge circuits) to achieve the functions of the low power rating on the transformers and power semiconductors and low current rating on the rectifier diodes and output inductors. Three half‐bridge circuits are stacked at the high voltage side to reduce the voltage stress of each power switch at one‐half of input voltage and connected in parallel at the low voltage side to share load current and reduce the current rating on each magnetic component and the rectifier diode. Thus, the size of the output chokes is reduced. In each half‐bridge converter, the asymmetric pulse‐width modulation is adopted to control power switches. Power MOSFETs can be turned on with zero voltage during the transition interval due to the resonant behavior by the output capacitance of MOSFETs and the leakage inductance (or external inductance) of transformers. Experiments based on a laboratory prototype with 1 kW rated power are provided to demonstrate the performance of proposed converter. Copyright © 2012 John Wiley & Sons, Ltd.     

一种直流侧带混合谐波抑制电路的24脉波整流器

常规12脉波整流器会对电网造成大量谐波污染。为同时提高整流器交、直流侧电能质量,提出了一种直流侧带混合谐波抑制电路(Hybrid Harmonic Suppression Circuit, HHSC)的24脉波整流器。所提整流器由常规12脉波整流器、抽头变换器(Tapped Inter-Phase Converter, TIPC)和补偿电路(Compensation Circuit, CC)组成。TIPC的输出端与负载串联,直接调制整流桥的输出电流和电压。CC与负载并联,间接调制整流桥的输出电流,然后根据交、直流两侧电流关系和直流侧电压关系,最终使整流器输入电流接近正弦波,输出电压由12脉波倍增至24脉波。该方法仅需小容量(仅为输出功率的2.65%)的HHSC即可有效降低输入电流谐波和输出电压纹波,具有高谐波抑制性能、低谐波抑制代价等优点。在Matlab/Simulink中搭建仿真模型,验证了所提方法的正确性和有效性。     

Series resonant high‐voltage DC–DC converter with reduced component count

This paper proposes a novel zero‐current‐switching series resonant high‐voltage DC–DC converter with reduced component count. The series resonant inverter in the proposed topology has two power switches (insulated‐gate bipolar transistors, IGBTs), two resonant capacitors, and only one high‐voltage transformer (HVT) with center‐tapped primary windings. The power switches are connected in the form of a half‐bridge network. The leakage inductances of the transformer's primary windings together with the resonant capacitors form two series resonant circuits. The series resonant circuits are fed alternately by operating the power switches with interleaved half switching cycle. The secondary winding of the HVT is connected to a bridge rectifier circuit to rectify the secondary voltage. The converter operates in the discontinuous conduction mode (DCM) and its output voltage is regulated by pulse frequency modulation. Therefore, all the power switches turn on and off at the zero‐current switching condition. The main features of the proposed converter are its lower core loss, lower cost, and smaller size compared to previously proposed double series resonant high voltage DC–DC converters. The experimental results of a 130‐W prototype of the proposed converter are presented. The results confirm the excellent operation and performance of the converter. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

一种适用于HVDC带双无源谐波注入的串联型36脉波整流器

为了提升海上风电并网HVDC系统中的串联型二极管多脉波整流器的谐波抑制能力,提出一种基于直流回路双无源注入电路的串联型36脉波整流器。该整流器采用两个辅助无源注入电路,通过电流调制后产生电压注入谐波,最终可将交流侧输入相电压由12阶梯波倍增至36阶梯波。分析了双无源注入电路工作原理及特性。在此基础上,推导了整流器交流侧输入电压表达式。并以电压谐波畸变率最小为目标,设计了注入变压器的匝比参数。最后结合工程应用,讨论了辅助无源电路中二极管开路故障时系统的容错能力。理论分析及仿真结果表明,所提出的整流器具有谐波抑制能力强、结构简单、可靠性高和鲁棒性强等优点,更适用于高电压大功率场合。     

Simplified quasi‐Z source indirect matrix converter

Conventional matrix converters have a limited voltage gain less than 0.866 and also require many power switches and additional input filter that ensures a low input current harmonics to the grid. Quasi‐Z source (qZS) indirect matrix converter can provide high voltage gain and ensure a sinusoidal input current without additional input filter, which requires 12 power switches in rectifier stage. In this paper, a simplified qZS indirect matrix converter is proposed to overcome aforementioned limitations and achieve (1) higher voltage gain than 0.866, (2) less power switches, and (3) LC‐filter function integrated in qZS network to avoid additional filter. The new converter's operating principle and equivalent circuits are analyzed, and the modulation method is presented. The input current closed‐loop control is employed to implement sinusoidal input current waveform even though the proposed converter has less power switches and without extra input filter. A test bench is used to verify the simplified qZS indirect matrix converter and control methods. Simulation and experimental results identically validate the proposed converter system with wide voltage gain range and low input current harmonics. Copyright © 2014 John Wiley & Sons, Ltd.     

Soft switching DC/DC converter with high voltage gain and less current ripple

A new soft switching three‐level converter with two DC/DC circuits in the primary side and current double rectifiers in the secondary side is presented to realize the zero‐voltage switching operation, reduce the transformer secondary winding turns and the output current ripple, and lessen the voltage rating of rectifier diodes. Two DC/DC pulse‐width modulation circuits sharing same power switches with interleaved half switching cycle are adopted in the proposed converter to reduce the current rating of transformer primary windings. Two inductors and four diodes are adopted in the secondary side to achieve current double rectifier, reduce output ripple current, and decrease the transformer secondary winding turns. Based on the pulse‐width modulation scheme, the power switchers can be turned on at zero‐voltage switching operation. Laboratory experiments with a 1.44 kW prototype are provided to verify the theoretical analysis. Copyright © 2016 John Wiley & Sons, Ltd.     

High‐efficiency current‐doubler rectifier with low output current ripple and high step‐down voltage ratio

This paper presents a current‐doubler rectifier with low output current ripple and high step‐down voltage ratio. In the proposed rectifier, two extra inductors are introduced to extend the duty ratio of the switches, which in turn reduces the peak current through the isolation transformer as well as the output current ripple; two extra diodes are used to provide discharge paths for the two extra inductors. To highlight the merits of the proposed rectifier, its performance indexes, such as voltage gain function, secondary winding peak current of the isolation transformer, and output current ripple, are analyzed and compared with the conventional current‐doubler rectifier. In this paper, a zero‐voltage‐switching phase‐shift full‐bridge converter with the proposed rectifier with an input voltage of 400 V, output voltage of 12 V, and full load power of 500 W has been implemented and verified, and experimental results have shown that 90% conversion efficiency could be achieved at full load. © 2013 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

A control method for the matrix converter based on virtual AC/DC/AC conversion using carrier comparison method

This paper proposes a novel control method based on the virtual AC/DC/AC conversion for the matrix converter. The virtual AC/DC/AC conversion method is a very simple strategy to control the input current and the output voltage for the matrix converter. There are two new topics proposed in this paper. First, this paper proposes the minimum switching loss modulation on the virtual rectifier. In our proposed modulation, only two arms switching in the virtual rectifier using DC link current control by the virtual inverter can obtain clean sinusoidal input current. Second, a novel lean controlled carrier modulation on the virtual inverter is proposed. The leans of the triangle carrier are controlled by the duty ratio of the rectifier side pulse. The lean controlled carrier reduces harmonic distortion of the input current by avoiding interference between the rectifier control and the inverter control. These new proposals are confirmed by simulation and experimental results. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 152(3): 65–73, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20144     

High output impedance CMQOs using DVCCs and grounded components

In this paper a new circuit topology for realizing second‐order current‐mode quadrature oscillator is proposed. Three additional circuits are further derived from it, thus resulting in four distinct circuits. Each circuit employs three differential voltage current conveyors and all grounded passive components, ideal for IC implementation. All the circuits possess high output impedance. The circuits exhibit non‐interactive frequency control and low THD. The effects of non‐idealities are also analyzed. PSPICE simulations using 0.5 µCMOS parameters confirm the validity and practical utility of the proposed circuits. Copyright © 2010 John Wiley & Sons, Ltd.     

基于AC电压估计和电流重构的PWM整流器研究

在详细分析PWM整流器数学模型的基础上,提出了一种基于交流电流重构和交流电压估计的PWM整流器控制方案,该方案同时去掉了交流输入电流和交流输入电压传感器,根据开关信号和直流电流对三相交流电流进行重构,利用交流输入电压估计器对三相交流输入电压进行估计,然后在d-q旋转坐标系中对交流电流的d,q分量进行解耦控制.实验结果表明,该方案在减小装置体积、节省成本、提高系统可靠性的同时,能够有效地抑制注入电网的谐波,使交流输入电流为正弦波,实现单位功率因数控制.     

使用六绕组隔离变压器的大电流整流器研究

为提高整流器的电流输出能力,设计了一种基于六绕组隔离变压器的大电流整流器。该整流器使用六绕组隔离变压器作为移相变压器,隔离变压器的原边绕组采用三角形联结,副边绕组相互独立,输出3组相位依次相差120°的单相电压,分别为3组单相整流桥供电,可有效增大电流输出能力。理论分析、仿真及实验结果表明,该大电流整流器的输入侧和负载侧的电能质量与传统的双反星形整流器相同,但电流输出能力为双反星形整流器的1.5倍;另外,该大电流整流器所用隔离变压器的容量要小于双反星形整流器所用变压器的容量,这在一定程度上可以提高该整流器的功率密度。     

A novel 12-pulse full-wave rectifier with simple circuit configuration

In this paper, a novel full-wave 12-pulse rectifier with simple circuit configuration is proposed. The proposed full-wave 12-pulse rectifier consists of a conventional six-pulse full-wave rectifier and an auxiliary single-phase full-bridge rectifier (ASFR). The ASFR extracts a rectangular current from the DC side of the rectifier to increase the output states of two three-phase half-wave rectifiers, then the conventional six-pulse full-wave rectifier is upgraded to a 12-pulse full-wave rectifier in accordance with the current relationship between AC and DC sides and the relationship between DC-side voltages. Since only a low-capacity ASFR (6.3% P_d) is needed, the proposed 12-pulse rectifier has the least number of components count, making it robust and simple to implement. The average output current of ASFR is only 6.7% of the load current, which makes it more suitable for low-voltage and high-current applications. A prototype with a power of 1 kW is built to verify the correctness of the theoretical analysis.     

Generation of current mode filters using NAM expansion

Systematic synthesis method to generate a family of current mode band‐pass–low‐pass circuits based on nodal admittance matrix (NAM) expansion is given. Eight equivalent circuits are obtained, five of them are new. Each of the generated circuits uses two grounded capacitors and three grounded resistors and two balanced output current conveyor (BOCCII) or two balanced output inverting current conveyor (BOICCII) or a combination of the two types. Generation of a low input impedance current mode band‐pass–low‐pass circuits based on NAM expansion results in 16 equivalent circuits. The NAM expansion is also used to generate 32 equivalent current mode universal filters using four BOCCII or BOICCII or a combination of the two types. Copyright © 2010 John Wiley & Sons, Ltd.     

变拓扑混合双12脉波整流器的电流预测控制

多脉波整流技术是大功率整流系统抑制谐波电流的主要手段之一,传统的24脉波整流器串联工作时存在网侧谐波电流过高的缺陷。为此,对传统24脉波整流器进行改造,通过增加若干切换开关,得到一种具有混合工作模式的变拓扑双12脉波整流器。研究了开关状态的不同组合与串联、并联和冗余工作模式的对应关系,详细分析了混合工作模式的等效电路和电流预测控制的实现机理,进一步研究了电流预测控制策略实现不同工作模式间的快速切换和输出电流的快速响应问题。最后,通过仿真分析和实验验证了电流预测控制策略的有效性,结果表明在相同负载电压下,混合模式的网侧谐波电流低于串联模式。