三相四线三电平APF并联运行有源阻尼方法

摘要

Due to its good filtering performance, LCL filter is more and more widely used in active power filters (APFs).For single APF application, the grid current feedback active damping (GCFAD) method is often used to attenuate the resonant spike of the LCL filters.However, when multiple APFs operate in parallel to increase the compensation capacity, the effect of the traditional active damping method is significantly reduced and even cause instability to the whole system.In this paper, a novel active damping method is proposed based on the LCL filter equivalent model of parallel-operated APF.The method adaptively adjusts the parameters of the active damping controller according to the number of the parallel APFs, which improves the robustness and the stability of the parallel APF system.The simulation and experimental results on three three-phase four-wire three-level APF parallel operating system verify the effectiveness of the proposed method.%由于滤波性能良好,电感-电容-电感(LCL)滤波器被越来越广泛地应用于有源电力滤波器(APF).对于单台应用的APF来说,一般采用基于并网电流反馈的有源阻尼方法衰减LCL滤波器的谐振尖峰.然而,在多台APF并联运行以提高补偿容量的场合,传统的有源阻尼方法抑制谐振的效果会显著降低,甚至造成系统无法正常运行.本文在推导并联运行APF的LCL滤波器等效模型的基础上,提出一种新型有源阻尼方法.该方法根据系统并联台数对有源阻尼控制器参数进行自适应调整,提高了APF并联运行系统参数的鲁棒性和系统的稳定性.在3台三相四线三电平APF并联运行系统上的仿真和实验结果验证了所提出方法的有效性.