Simulation and Experimental Implementation of Single Phase Active Power Filters for Improving Power Quality

Abstract

This paper presents single phase series and shunt active filters to improve power quality by reducing various power quality problems including current harmonics, voltage sag, voltage swell and voltage flicker. Voltage quality is improved by series active filter by injecting compensating voltage and current quality is improved by shunt active filter by injecting compensating current. Control strategy of series active filter contains two main loops, one is for output voltage control loop and another one is DC link voltage control loop. Control strategy of active filter should maintain constant voltage across DC side of the H Bridge and second objective is to maintain harmonic free sinusoidal source current in phase with source voltage. Simulation and experimental results are carried out for both filters to check the effectiveness of proposed control strategies.