Three-phase four-leg shunt active power filter to compensate harmonics and reactive power

This paper presents a compensating system for the harmonics and the reactive power using four-leg shunt active power filter (SAPF) in a three-phase four-wire distribution network and aims to minimize the harmonics and neutral current. Two control approaches p-q theory based hysteresis current control and load current detection based hysteresis current control are proposed. To validate the compensation performance of SAPF a distribution network with nonlinear loads is simulated using MATLAB/Simulink software. Simulation results are presented to assess the performance of SAPF to minimize the total harmonics distortion (THD) and neutral current, as well as to compensate the reactive power.