一种基于单位功率因数控制的有源电力滤波器

Active Power Filter by Unity Power Factor Control

为解决谐波污染、改善电能质量,采用基于单位功率因数的控制方法,提出了一种只需检测系统侧电流及逆变器直流电容电压,而无需实时检测、计算负载谐波电流,直接控制系统侧电流为与电网电压同相的标准正弦波的控制方法,其补偿电流的控制策略采用比例积分控制和三角波调制。按照H桥逆变器的单极性脉宽调制的主电路研制了一台高性能的5kVA单相有源电力滤波器实验样机。理论分析、仿真及实验结果证明该有源电力滤波器可同时实现补偿负载无功及谐波电流,控制简单且具有良好的动态性能。

A high performance single-phase active power filter （APF） was designed based on the unity power factor control. Without detecting and calculating the reactive current and harmonic current of the load, a new control method was proposed with which only the current of the power supply and the voltage of the DC capacitor of the inverter need to be detected, and the current of the power supply is made to be a standard sine wave with the same phase as the voltage of the source. The control strategies of compensation current are the PI control and the triangle wave modulation. The modulation of H-bridge inverter of the active power filter is unipolar Pulse Width Modulation （PWM）. The performances of the single phase active power filter are analyzed in detail under steady and dynamic state. At last a 5 kVA laboratory apparatus is developed. The simulation and experiment results demonstrate that the active power filter can compensate the reactive component and harmonics of load current, its control is very sim- ple, and the good real-time performance and dynamic performance are also verified by simulation and experiment.