基于a-b-c坐标下三相并联有源滤波器的补偿新策略分析

New compensation strategy for three-phase shunt APF based on a-b-c coordinate

并联有源滤波器在消除谐波电流和无功补偿(包括线性负载和非线性负载的无功补偿)方面发挥着重要的作用。目前,电力有源滤波器(APF)多采用基于瞬时无功功率理论的谐波和无功电流检测方法。这些方法大多要进行坐标之间的转换,并且在三相电路、电源都不对称的情况下很难做到对基波无功和高次谐波电流的准确检测。提出一种不需要在进行坐标转换,直接在坐标系下进行无功和谐波检测的方法。研究和仿真表明这种方法在电压源不对称、畸变和负载不平衡的情况下仍能有效工作,并且有效简化了并联有源滤波器(APF)的控制电路。

The shunt active power filter has proved to be a useful device to eliminate harmonic currents and to compensate reactive power for and linear/nonlinear loads. At present, detecting methods of reactive and harmonic currents based on the instantaneous reactive power theory are main streams. This paper presents a novel approach to determine reference compensation currents. The proposed approach neednt coordinate conversion. Simulation and experiment results show that the proposed approach can work well under source voltage asymmetry, non sine and unbalanced loads. In addition, the proposed approach yields a simpler design of the shunt APF controller.