Novel active filter system composed of inverter bypass circuit for suppression of harmonic resonance

We have developed a novel harmonic compensation system consisting of shunt LC filters on the load side, a step‐down transformer on the receiving end, and a small‐capacity active filter with one end connected to the secondary winding of the transformer and the other to the load bus. The active filter which constitutes the bypass circuit for the main service transformer is current‐controlled to give adequate damping of the harmonic resonance caused by the inductance behind the load bus, especially at lower harmonic frequencies. We have installed this new compensation system in combination with a TCR‐type SVC and shunt LC filters at the Yamanashi Maglev Test Line. We present an outline of the reactive power and harmonic current compensation systems, and harmonic resonance test results which show satisfactory performance of the active filter. © 1999 Scripta Technica, Electr Eng Jpn, 129(1): 82–90, 1999     

降低逆变器容量的混合有源电力滤波器控制方式

针对一种降低逆变器容量的混合有源电力滤波器,详细介绍了其在三种控制方式下的工作原理、性能特点和等效电路,搭建了容量为10kV.A的混合有源电力滤波器实验样机,并进行了三种控制方式的实验和分析.实验结果表明,采用复合控制方式,该结构中逆变器容量仅为整个滤波器容量的4.42%,而该滤波器投入后,电网电流总谐波畸变率从26.95%下降到4.25%,补偿效果良好且优于其他两种控制方式.     

Combined system of a series active filter and a shunt passive filter—an optimum design of the shunt passive filter

The combined system of a series active filter and a shunt passive filter that is proposed by the authors has the ability to eliminate a major disadvantage of shunt passive filters, namely, harmonic amplification. The series active filter needs a much smaller kVA rating than a conventional shunt active filter, and as a result, the combined system has good filtering characteristics and high efficiency. This paper presents an optimum design of the shunt passive filter that makes possible a great reduction in the required kVA rating of the series active filter. It can minimize the peak voltage across the series active filter and reduce the required kVA rating of the filter to 60 percent. A computer simulation geared to practical applications of large three-phase. twelve-pulse thyristor rectifiers is used to compare the compensation characteristics of the optimized system with those of a combined system that uses a conventional shunt passive filter. Experimental results obtained with a laboratory model of the filter corroborate the design approach.     

混合有源电力滤波器新型控制策略及稳定性分析

在分析混合型有源电力滤波器(HAPF)工作原理的基础上,对其两种控制策略下谐波和谐振抑制特性进行了分析和对比,提出了同时检测电源谐波电流和电源谐波电压来控制HAPF输出电流的新型控制策略,应用劳斯判据对其稳定性进行了详细分析,分析结果表明系统变得稳定,谐波补偿效果变得理想。仿真及实验结果验证了本文所述控制策略在谐波控制及系统稳定的有效性和可靠性。     

注入式混合型有源电力滤波器的研究

根据配电网10kV高压侧对大容量谐波抑制与无功补偿的要求,提出注入式混合型有源电力滤波器拓扑结构(IHAPF),详细阐述了IHAPF的谐波抑制特性.同时结合某铜箔厂大型整流装置谐波抑制和无功补偿的工程实例,介绍了IHAPF的设计方法和软硬件构成,并从项目成本和治理效果两方面分析了IHAPF的应用优势.     

Experimental verification of the effect of a voltage‐detection‐based shunt active filter for harmonic damping throughout a power distribution line

This paper is focused on a voltage‐detection‐based shunt active filter for installation on a power distribution system. A main objective of the active filter is to achieve damping of harmonic propagation coming from series/parallel resonance between capacitors for power factor correction and line inductors in the distribution system. The active filter installed at the end terminal of a distribution feeder is controlled in such a way as to present infinite impedance to the external circuit for the fundamental frequency, and to exhibit low resistance for harmonic frequencies. As a result, the active filter acts as a damping resistor for the harmonic propagation, like a 50‐Ω terminator installed at the end of a signal transmission line. It is verified by experiment that the active filter intended for harmonic termination has the capability of harmonic damping throughout the distribution feeder. © 2000 Scripta Technica, Electr Eng Jpn, 133(2): 1–10, 2000     

Analysis of harmonic propagation in a power distribution system: An application of a distributed constant‐circuit model

This paper discusses harmonic propagation and damping in a long‐distance distribution feeder having many capacitors for power factor correction, and presents harmonic damping characteristics of a shunt active filter based on voltage detection. A distributed constant‐circuit model for the feeder is derived to perform analysis with the focus on harmonic propagation and damping. As a result, it is clarified by theory and experiment that harmonic propagation throughout the feeder can be mitigated by installing the active filter, which acts as a harmonic terminator, on the end terminal of the feeder. © 2002 Scripta Technica, Electr Eng Jpn, 139(1): 73–81, 2002; DOI 10.1002/eej.1148     

有源滤波技术现状及其发展

随着各种功率器件的广泛应用,大量的谐波和无功电流注入电网,引起电网污染,造成电网电能质量问题日益严重。过去,国内外大量采用无源滤波装置来进行谐波抑制和无功补偿,提高功率因数。但无源滤波装置也存在着自身无法克服的不足和缺陷,因此有源滤波技术成为近几十年以来学术和工程界的研究热点。本文对有源滤波技术的历史发展作了简要回顾,详细介绍了有源滤波器的分类,重点比较了现有的和提出的有源滤波器信号检测以及控制方法,同时展望了有源滤波器的发展前景。这些技术的发展可使有源滤波器获得更好的性能和更广泛的应用。     

电网谐波功率潮流方向与电力滤波器的应用

分析了电网谐波功率潮流方向对其安装的无源滤波器和有源滤波器的影响,证明了只有根据电网谐波功率潮流的方向和谐波源类型来确定所使用的滤波器及其工作方式才能达到预期的滤波效果。     

单相家用电器负载瞬时谐波补偿的应用研究

将用1个PLL电路、4个乘法器、2个LPF、2个加法器实现单相电路瞬时谐波电流检测的方法应用于家用电器谐波补偿用有源电力滤波系统中,通过计算机仿真研究其控制性能,并构成了缩小变压器模型的实验系统进行实验,通过仿真及实验结果证明了单相瞬时谐波电流检测方法在实际系统中的实用性。     

一种新型注入式混合有源电力滤波器

针对传统的注入式混合型有源电力滤波器(IHAPF)的有源部分与基波谐振支路间会产生很大基波环流的问题,本文提出了一种新型注入式混合型有源电力滤波器拓扑结构以提高系统的安全性。本文首先分析了IHAPF系统基波环流产生的机理,并提出了能有效抑制基波环流的新型注入式混合型有源电力滤波器拓扑结构;然后,从串联谐振支路谐波分压和并联谐振支路谐波分流两个方面分析了新型结构的优越性。最后,仿真与物理实验结果表明,该结构不仅能够有效地解决中高压系统中大容量无功和谐波综合治理的难题,还可以抑制传统注入式结构中存在的基波环流,大幅度提高了装置的安全可靠性。     

Dynamic companion harmonic circuit models for analysis of power systems with embedded power electronics devices

In this paper a methodology that extends the dynamic harmonic domain (DHD) analysis of large networks is presented. The method combines DHD analysis and discrete companion circuit modeling resulting in a powerful analytic technique called dynamic companion harmonic circuit modeling. It provides for a complete dynamic harmonic analysis of the system while preserving the advantages of discrete companion circuit models. The methodology is illustrated by its application to a three-node power system, where reactive power compensation is achieved using a fixed-capacitor, thyristor-controlled reactor (FC-TCR) and its control system.     

基于DSP-ARM的并联有源电力滤波器控制器

针对三相并联型有源滤波器,从能量守恒角度提出一种将周期离散控制技术和数宁锁相环技术应用于直流侧电容电压控制的策略.设计了基于DSP-ARM的全数字控制系统,仿真和实验结果证明,设计的控制系统运算速度快,能跟踪和补偿频繁变化的负荷谐波.     

背景谐波电压对混合型有源滤波器的影响及对策

结合已有的工程经验,分别从整个混合滤波系统和有源部分的电压型逆变装置2个层面开展谐波电压对并联混合型有源滤波器影响的分析,得出谐波电压可能导致系统谐振以及直流侧电压抬升的结论。在此基础上,提出在开始设计混合滤波系统参数时就考虑相关参数的配合以避免与系统发生谐振并尽可能降低有源部分谐波分压,同时对直流侧电压采取合适的控制策略或设置有效的泄放回路以防止其飙升等方法来有效消除谐波电压对装置性能的影响,最后通过仿真实验进行了验证。     

新型混合型滤波器设计

根据目前常见的几种混合有源滤波器,提出一种注入式混合有源滤波器,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。阐述混合有源滤波器和注入式有源滤波器的工作原理,通过样机实验验证结论正确性。     

注入式混合型有源电力滤波器直流侧过电压产生的机理及抑制方法

注入式混合型有源电力滤波器是一种应用较为广泛的谐波治理装置,一般采用不可控整流电路来维持直流侧电压.但是当电网谐波电压含量较高时系统中存在的直流侧过电压现象严重威胁着有源滤波系统的安全,目前对这方面的研究很少.本文在分析注入式混合型有源电力滤波器工作原理的基础上,着重探讨了IHAPF系统直流侧过电压产生的机理.从谐波治理效果和系统安全性等方面研究了直流侧过电压对注入式混合有源滤波系统性能产生的影响,提出了从优化注入支路参数和改进APF主电路结构等方面提高系统安全性的方法.根据本文所述方法,为某冶炼厂研制了"注入式混合型大功率有源滤波系统",运行结果表明了该方法的有效性.     

基于并联变压器的新型有源电力滤波器控制策略

提出了一种由并联变压器和电压源型逆变器组成的新型有源电力滤波器控制策略。具体方法：将变压器一次绕组与谐波源并联,检测变压器一次侧基波电压作为指令信号,控制电压源型逆变器的输出电压加在变压器的二次侧,当逆变器输出电压与变压器一次侧基波电压满足一定条件时,对基波分量而言,有源电力滤波器等效为一个可调电抗以补偿无功;对谐波分量而言,有源电力滤波器等效为变压器漏抗,从而疏导谐波流入变压器一次绕组。最后的仿真结果验证了该策略的可行性。     

A new method of damping harmonic resonance at the DC link in a large‐capacity rectifier‐inverter system

This paper proposes a new method of damping harmonic resonance in the DC link of a large‐capacity rectifier‐inverter system, such as in rapid‐transit railways. A voltage‐source PWM converter is connected in series to the DC capacitor of the rectifier through a matching transformer, acting as a damping resistor to the DC capacitor current. No filters are needed to extract harmonic components from the DC capacitor current. This results in a quick response and highly stable damping. The relationship between the control gain of the PWM converter and the required rating is theoretically discussed. We show that the required rating is less than one‐thousandth of that previously proposed. In particular, regenerating the power consumed by the PWM converter is very important because of the large power in practical systems. Normally, an additional PWM inverter is connected to the DC bus of the PWM converter to regenerate the consumed power. The additional inverter regenerates the DC power to the AC source through a transformer. This method, however, makes the damping circuit complex, thus the proposed method for the DC‐link harmonic resonance is less practicable. In this paper, a simple and novel scheme that utilizes the DC‐link voltage of the rectifier as a DC source for the PWM converter is proposed. The excellent practicability of the proposed damping method with the novel regenerating scheme is confirmed using digital computer simulation. © 2003 Wiley Periodicals, Inc. Electr Eng Jpn, 144(2): 53–62, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10172     

RAPF电力有源滤波装置用于厂矿企业配电网高次谐波治理

针对目前大型能源企业谐波污染严重且治理效果不理想的现实情况,提出了企业电容器补偿装置已投运现状下的有源滤波、无功补偿综合治理方案,在介绍有源滤波装置的各项功能设计特点的基础上,对该混合补偿方案进行了工业现场模拟实验。工程应用效果表明,所提出的与并联电容器组的混合补偿技术方案不但充分利用了企业原有的无功补偿设备,而且发挥了有源滤波装置补偿小容量谐波的高性能、低成本特点,因而具有较高的工程应用价值。     

Experimental verification of dispersed installation of shunt active filters based on voltage detection for harmonic damping throughout power distribution systems

This paper deals with dispersed installation of voltage‐detection based shunt active filters for harmonic damping throughput a power distribution system. A main objective of the active filters is to achieve damping of harmonic propagation coming from series/parallel resonance between capacitors for power factor correction and line inductors in the distribution system. Either a harmonic current source or a harmonic voltage source is connected to a distribution system simulator consisting of two distribution feeders, each of which is rated at 200 V and 20 kW. A couple of active filters are installed to the simulator. As a result, it is clarified by experiment that dispersed installation on the end bus of each feeder is effective in attenuating the harmonic propagation. © 2001 Scripta Technica, Electr Eng Jpn, 138(1): 14–23, 2002