A control scheme employing an adaptive hysteresis current controller and an uncomplicated reference current generator for a single-phase shunt active power filter

Abstract

In recent years, active power filters (APFs) have become popular because of their excellent current harmonics and reactive power mitigation ability. The performance of the APF is directly related to the selected control strategy, which is mainly divided into 2, the reference current generation and current control. Most of the reference current generation methods are very complicated and require precise mathematical expressions. Moreover, being the most preferred current control method, conventional hysteresis controllers have a fixed bandwidth, which causes difierent total demand distortion values under difierent load conditions. In this study, a novel control scheme for a single-phase shunt APF is proposed. The proposed scheme uses an uncomplicated modification of the sine multiplication method for extraction of the reference filter current. Moreover, it employs an adaptive hysteresis current controller that changes its bandwidth according to the active power demand of the load. Thus, the requirements of the current harmonics limits specified in IEEE Std. 519-1992 are always fulfilled under difierent load conditions. A single-phase shunt APF controlled by the proposed scheme is modeled and simulated under nonlinear load conditions using MATLAB/Simulink. The simulation results indicate that the APF effectively compensate the current harmonics and reactive power at the point of common coupling of the AC mains.