Research of Active Power Filter Based on Sliding Variable Structure Control

The nonlinear mathematical model of active power filter(APF) for three-phase three-wire system was built by use of three-legged converter as main circuit.Aiming at the poor dynamic performance of power electronics converter device,a sliding-mode control algorithm frame for the current-loop was proposed,and the traditional PI control for the out-voltage-loop was proposed.The experimental results show that this method has a quick dynamic response,strong robustness and better harmonic control performance.