基于粒子群算法的APF直流侧电压控制

直流侧电压的的控制影响到有源电力滤波器(APF)的功率损耗和补偿性能,以三相三线制APF为研究对象,推导APF电压环传递函数为被控对象,构造简化定常系统和加入时变环节的时变系统。针对传统PI控制参数难整定、时变系统适应性差的问题,将引入收缩因子和惯性权重线性递减的粒子群算法(PSO)纳入到PI参数的优化中,合成离线PSO-PI控制和在线PSO-PI控制。仿真表明,较传统PI控制,在线PSO-PI控制对时变系统具有超调量小、响应快、适应性强的特点。     

混沌开关电源输出端有源滤波器的设计

混沌扩频技术是从源头上改善高频开关电源EMC特性的一种有效方法,但同时开关电源输出电压的纹波会随频率调制系数的增大而有所增加.为使输出电压的纹波降低到原来的水准,本文在开关电源的输出端增加一个简单的有源滤波器.这个有源滤波器结构简单、成本低、体积小、对开关电源输出电压的动态特性影响不大.本文主要阐述这个有源滤波器的设计.     

基于无差拍SVPWM的有源滤波器研究

采用无差拍电压空间矢量控制法来分析有源滤波器的滤波性能,给出该方法的控制策略,包括空间矢量脉宽调制（SVPWM）算法以及无差拍原理。该方法可以用来抑制和消除采样与计算方法的延时对控制精度的影响。Matlab仿真结果表明：SVPWM调制与无差拍控制结合用于有源滤波控制可以明显改进补偿的动态性能,提高滤波效果。实验结果证明该方法可行,且具有较好的实时性。     

Control techniques for a high power factor multilevel rectifier based on double boost converter

In this paper three novel control schemes for the single-phase ac/dc converter with two-level or three-level pulse width modulation are proposed to improve the power quality. A diode rectifier with two power switches is adopted as a power factor correction circuit to achieve high power factor and low harmonic distortion. The proposed control schemes are based on look-up tables with a hysteresis current controller instead of the conventional complex control algorithm. The proposed control scheme can (1) draw a sinusoidal line current, (2) achieve a unity power factor and (3) improve voltage unbalance problem on the dc bus capacitors. The software simulations and experimental results are shown to verify the proposed control algorithms. It is shown that the measured harmonic currents and input power factor satisfy the international standard requirements such as International Electrotechnical Commission 1000-3-2.     

基于LT1568的高频段有源滤波器的设计

对于高频信号,传统的由分立元件搭建的LC无源滤波网络,设计过程复杂,对信号衰减较大。为了简化高频段滤波器的设计过程、提高滤波效率,提出了使用低噪声高频有源RC滤波芯片LT1568来设计高频滤波电路,介绍其性能,分析了其工作原理。并以高频多普勒接收机内部带通滤波器设计为例,介绍滤波电路的设计方法。实验仿真表明用其搭建的高频有源滤波电路滤波效果明显、电路简单、方便易用。     

基于间谐波检测的有源滤波器设计

配电网中的间谐波是引起电压闪变的重要原因。针对上述问题,设计了基于巴特沃斯滤波器的并联型有源滤波器,并以上海某港口配电系统的谐波状况为实例进行了仿真研究。仿真结果表明:该有源滤波器能够较好的滤除电网中的间谐波电流,抑制电压闪变。证明了该方案合理,有效。     

Dual sepic PWM switching-mode DC/DC power converter

A steady-state analysis and experimental results for a dual sepic pulse-width-modulated (PWM) DC/DC power converter for both continuous and discontinuous modes of operation are presented. The converter is dual to a sepic converter, but it can also be derived from a forward converter by replacing one of its rectifier diodes with a coupling capacitor. The circuit acts as a step-down or step-up converter, depending on the value of the ON switch duty cycle. The transformerless version of the converter has a positive DC/DC voltage transfer function. Therefore, the circuit is suitable for distributed power systems. Design equations for all circuit components are derived. Experimental results measured at 100 kHz were in good agreement with theoretical predictions     

A series active power filter based on a sinusoidalcurrent-controlled voltage-source inverter

A series active power filter working as a sinusoidal current source, in-phase with the mains voltage, has been developed and tested. The amplitude of the fundamental current in the series filter is controlled through the error signal generated between the load voltage and a pre-established reference. The control allows an effective correction of power factor, harmonic distortion and load voltage regulation. Compared with previous methods of control developed for series active filters, this method is simpler to implement because it is only required to generate a sinusoidal current, in-phase with the mains voltage, the amplitude of which is controlled through the error in the load voltage. The proposed system has been studied analytically and tested using computer simulations and experiments. In the experiments, it has been verified that the filter keeps the line current almost sinusoidal and in-phase with the line voltage supply. It also responds very quickly under sudden changes in load conditions, reaching its steady-state in about two cycles of the fundamental     

Quasi current resonant DC link AC/AC converter

A new quasi current resonant DC link (QCRDCL) topology has been developed in this paper. Although prototype current resonant DC link topologies for AC/AC power conversion have had such problems as irregular high current peaks, uncontrollable pulse width, etc., this new topology enables the AC/AC conversion system to have the properties wherein the current peak is limited and the pulse width is adjustable. The system begins to assume an adjustable-width flat-topped current shape, whereby the system becomes particularly suitable for high power application. With control of the pulse width a very fine load current regulation can be obtained. In this system, an open loop PWM control has been adopted and almost the same quality of output waveforms as the conventional current source inverter has been achieved     

Advanced power semiconductors and ICs for DC/DC converter applications

This paper describes recent advances in power semiconductor devices, integrated circuits, and packages for DC/DC converter applications. Special emphasis is placed on the latest discrete power MOSFET devices and packages. Features and trends in ICs for control of synchronous buck converters are highlighted as well. The paper will also cover a new class of miniaturized hybrid assembly that sets new efficiency standards for high current low output voltage applications.     

PCB integrated inductors for low power DC/DC converter

This paper discusses the use of printed circuit board (PCB) integrated inductors for low power DC/DC buck converters. Coreless, magnetic plates and closed core structures are compared in terms of achievable inductance, power handling and efficiency in a footprint of 10 /spl times/ 10 mm/sup 2/. The magnetic layers consist of electroplated NiFe, so that the process is fully compatible with standard PCB process. Analytic and finite element method (FEM) methods are applied to predict inductor performance for typical current waveforms encountered in a buck converter. Conventional magnetic design procedures are applied to define optimum winding and core structures for typical inductor specifications. A 4.7 /spl mu/H PCB integrated inductor with dc current handling of up to 500 mA is presented. This inductor is employed in a 1.5 W buck converter using a commercial control integrated circuit (IC). The footprint of the entire converter measures 10 /spl times/ 10 mm/sup 2/ and is built on top of the integrated inductor to demonstrate the concept of integrated passives in power electronic circuits to achieve ultra flat and compact converter solutions.     

A versatile power converter for high-frequency link systems

A single-phase high-frequency link appears to be an attractive alternative to the DC link commonly used in power conversion systems. The authors propose a power converter suitable for one-step conversion of the single-phase high-frequency link voltage to the three-phase low-frequency voltages typically required for interfacing with system sources and loads. The converter utilizes zero voltage switching principles to minimize switching losses and uses an easy-to-implement technique of pulse density modulation for the control of the amplitude, frequency, and waveshape of the synthesized low-frequency signals. Adaptation of the proposed topology for power conversion to single-phase AC and DC voltage or current outputs is shown to be straightforward. The feasibility of the proposed power circuit and the control technique have been experimentally verified     

基于滑模控制的三相四线制有源滤波器的研究

为了实现三相四线制系统中有源滤波器电流跟踪控制的快速性和鲁棒性．提出了一种基于滑模控制的有源滤波器。在d-q-0坐标系中建立三相四线有源滤波器的数学模型,通过逆系统的方法实现解耦和线性化,并对滑模控制的趋近律进行改进以削弱抖振、加快跟踪速率。仿真结果表明,采用滑模控制实现指令电流跟踪的有源滤波系统鲁棒性强、快速性好、跟踪误差低,总体性能得到明显提升。     

A novel active power filter based on the least compensation currentcontrol method

A new least compensation current technique to detect the harmonic and reactive current for active power filters is presented in this paper. With the technique, a novel active power filter based on the least compensated current control is proposed, in which the measurement of harmonic and reactive current and the generation of compensated current are completed in the same closed-loop. Compared with the existing control methods of active power filter, the proposed method has simpler structure, quicker dynamic, higher reliability and better compensation performance. Simulating and experimental results are provided that verified theoretical predictions and demonstrate the effectiveness of the proposed control method and circuit configuration     

A novel ZVS DC/DC converter for high power applications

This paper presents a novel zero voltage switch (ZVS) pulse-width modulation (PWM) DC/DC converter for high power, high output voltage applications. By using two active switches in the secondary side of a transformer, the proposed converter achieves not only ZVS of the active switches in the entire load ranges but also soft commutation of the output rectifier diodes. The proposed topology has simple structure and control strategy. Simulation results and experimental results of a 2.8 kW 200 kHz DC/DC converter are presented.     

Comparisons of PWM and one-cycle control for power amplifier with multilevel converter

Based on the concepts of cascade multilevel converters and one-cycle technique, comparisons are conducted to characterize the distortion of the pulsewidth modulation (PWM) and one-cycle control methods that were applied to converters. Simulation results for the different control schemes are obtained in PSIM software initially to see the effect of one-cycle control different from that of PWM control. Through the comparisons, the advantages and disadvantages are identified for each method. The one-cycle scheme is better than PWM control in reducing undesirable harmonics and tracing dynamic waveforms. Simulation and experimental results are also provided to verify the conclusions.     

一种新型混合型有源电力滤波器的研究

提出了一种单相并联混合型有源电力滤波器的电路结构.该电路由有源滤波器与基波串联谐振支路并联再与无源滤波电路串联构成,用于抑制非线性整流负载产生的谐波电流流入电源侧.在该电路中,无源滤波器分担大部分抑制谐波和无功补偿的任务,减少了有源滤波器的容量;有源电力滤波器用于改善无源滤波器的滤波效果,抑制它与系统阻抗可能发生的谐振.实验结果表明,该混合型有源滤波器充分发挥了无源滤波器和有源滤波器各自优点,改善了无源滤波器的滤波性能,同时使有源滤波器不再承受基波电压,最大限度地减少了有源滤波器的容量,从而使有源电力滤波器可应用于大功率场合.     

基于一致性算法的级联H桥直流变换器研究

针对多个H桥的接入和接出,造成各路变流器不均流均压问题,提出群系统一致性策略对群H桥模块进行协同控制。考虑H桥通信拓扑和信息交互权值以及H桥模块接入和接出系统等情况,分析了系统稳定特性,然后将所有H桥一致性信息与电压电流双闭环控制策略相结合,实现了群H桥电流状态快速一致和电压的稳定。通过Matlab/Simulink仿真结果表明,所提出的控制方案能有效地实现群H桥变流器的电流一致和电压稳定,提高系统的鲁棒性,对大规模的混合储能接入微电网有一定的理论意义。     

High power laser diode driver based on power converter technology

This paper describes the design of a high speed semiconductor laser diode driver designed for driving 500 mW to 1.5 W diodes at full optical power modulation up to frequencies of 10 MHz. The duty cycle of the modulation may be varied. A switching power-converter based current source allows a higher power delivery efficiency to the diode than in previous designs, allowing for a more modest power supply and dissipation requirements. A dynamic ripple cancellation circuit reduces the power converter output current ripple to less than 1% of full-scale current. The circuit is capable of delivering up to 2.5 A to a laser load, with a 10-90% switching risetime from laser threshold to full on of less than 20 ns     

An AC/DC converter with high power factor

The television receiver often employs a capacitor-input-type rectifier. In this case, it is regulated as a class D piece of equipment. This paper presents a novel ringing-choke-converter-type switching regulator, which functions as an active filter. The proposed circuit features a simple circuit configuration and cost effectiveness. It achieves a high power factor of about 0.95 and reduces current harmonics (third, fifth, and seventh) in the AC input current to less than 40% of the limit value for class D. The voltage across the input smoothing capacitor does not show large variations and the components in the conventional ringing-choke converter can be used unmodified. Ripple content of the DC output voltage shows a slight increase and is the subject for future research.