三相并联型有源电力滤波器补偿电流性能分析与改进

Performance Analysis and Improvement of Output for Three Phase Shunt Active Power Filter

三相有源电力滤波器通常用来补偿非线性负载所引起的谐波和无功电流。在有源电力滤波装置中,其补偿性能的好坏,很大程度上取决于控制器的设计。但由于非理想因素的影响,例如输出电流环路带宽有限、检测电路的延时、指令电流的产生等,都会影响补偿效果,而传统的PI控制由于带宽有限不能实现无静差输出。为了提高三相并联型有源电力滤波器的补偿性能,该文在同步旋转坐标系下提出了一种理想的电流控制策略即基于PI控制和重复控制并联结构的电流控制方法,利用重复控制对于周期扰动信号无差跟踪的特点来提高有源滤波的稳态精度,PI控制保证有源电力滤波器的动态性能。实验结果和理论分析充分证明了所提并联结构电流控制器的可行性。

Three-phase shunt active power filter （APF） are often used to compensate the harmonic and reactive current derived from non-linear load. But many non-ideal factors, such as the limited bandwidth of output current loop and the time lag of signal sensing circuit and reference current generation etc, will deteriorate the compensation effect. Proportion-Integral （PI） controller cannot be used simply to control the output current without any steady error due to its limited current tracking capability. A novel output current control architecture in the synchronous rotating frame with ordinary PI and advanced repetitive controller （RC） in parallel is put forward in this paper to enhance the compensation characteristic of three-phase shunt APF. The advanced repetitive controller in parallel is used to eliminate the steady current tracking error caused by cyclic disturbance signal to improve the compensation precision of APF, while the ordinary PI controller is used to ensure the dynamic response performance of APF. The feasibility of this output current controller architecture is verified completely by theoretic analysis and experimental results in detail.