基于LCL滤波器的并联有源电力滤波器电流闭环控制方法  

Current Loop Control Approach for LCL-based Shunt Active Power Filter

作　　者：仇志凌[1] 杨恩星[1] 孔洁[1] 陈国柱[1] 

机构地区：[1]浙江大学电气工程学院,浙江省杭州市310027

出　　处：《中国电机工程学报》2009年第18期15-20,共6页Proceedings of the CSEE

基　　金：新世纪优秀人才支持计划项目(NCET-06-0512)~~

摘　　要：并联有源电力滤波器(active power filter,APF)需要具有较高的补偿带宽和较低的开关纹波含量。LCL滤波器由于可以兼顾低频段增益和高频段的衰减,是APF输出滤波器的较好选择,但LCL滤波器是3阶系统,增加了控制难度。通常应用于APF电流控制的瞬时值反馈内环结合重复控制外环的双环控制性能较好,但其主要是针对单电感滤波器进行设计,难以直接应用于LCL滤波器控制。提出一种简单的内环方案,利用数字控制固有的一拍计算延时进行LCL滤波器的稳定控制,只需一个反馈量,结构简单;由于内环有效地改善了系统的特性,作为外环的重复控制器的设计相对简单。基于LCL滤波器的双环控制方案赋予了系统较高的稳态补偿精度和快速的动态响应。实验结果证明了所提出控制方法的有效性。Shunt active power filter （APF） is suitable for compensation of current-type harmonics generated by nonlinear load, but high compensation precision is difficult to be achieved due to very high slew？ rate of harmonic current, output impendence of voltage source converter （VSC） and control loop phase lag. LCL-filter reserving sufficient attenuation ration for switching ripple with small LC parameters is suitable to be used as output filter to get high slew rate of compensation current. However, LCL-filter, as a three order one, is difficult to be stable. A simple control method is proposed with one beat delay introduced to feedback current. Meanwhile, repetitive control algorithm, as outer control loop, is adopted to eliminate steady-state error of the whole control system. Based on this double-loop control scheme, very high quality steady-state grid current waveform and fast dynamic response can be obtained. Simulation results validate the feasibility of the method proposed by this paper.

关 键 词：并联型有源电力滤波器 高质量电网电流 LCL滤波器稳定控制 重复控制 

分 类 号：TM77[电气工程—电力系统及自动化]