三相四线制有源电力滤波器指定次数谐波控制策略

针对三相四线制低压配电网不平衡非线性负载的电能质量问题,提出采用矢量谐振控制器对电容分离型有源电力滤波器(Active Power Filter,APF)进行指定次数谐波控制方案。在αβγ坐标系下对电容分离型APF进行建模,省去了在dq坐标系下的电流交叉解耦环节。比例谐振控制器应用在APF闭环控制系统时,存在各次谐振点附近谐振尖峰影响闭环控制系统稳定性和补偿精度的问题,采用矢量谐振控制器实现指定次数谐波跟踪控制,其分子零点与控制对象的极点抵消,实现控制系统降阶,提高了控制性能。仿真结果表明,所提控制方法在针对指定次数谐波补偿方面有着良好效果,其三相不平衡被抑制,直流侧电容电压得到均衡控制,证明了所提方法有效性。

Control Strategy based on Specific Harmonic Compensation for Three-Phase Four-Wire Active Power Filter

In view of the power quality of unbalanced nonlinear load for the three-phase four wire low voltage distribu-tion network, the control scheme of using vector proportional resonant controller to suppress specific harmonic is pro-posed.The split-capacitor-type active power filter ( APF) mathematical model is established based onαβγcoordinate system, and current cross decoupling link under dq coordinate system is omitted.The proportional resonant controller is applied in the closed-loop control system of APF, and the resonance peak near the resonance point can affect the stability and compensation precision.In this paper, the vector resonance controller is adopted to suppress specific har-monic tracking control, and the zero point of the controller can molecule the pole of control object, thus the three-phase unbalanced order of control system is reduced to improve the control performance, and the DC side capacitor voltage is also controlled in balance.The simulation results verify the validity of the proposed method.