Abstract: “Recently wide spread of power electronic equipment has caused an increase of the harmonic disturbances in the power systems. The nonlinear loads draw harmonic and reactive power components of current from ac mains. Current harmonics generated by nonlinear loads such as adjustable speed drives, static power supplies and UPS. Thus a perfect compensator is required to avoid the consequences due to harmonics. To overcome problems due to harmonics, Shunt Active Power Filter (SAPF) has been considered extensively. SAPF has better harmonic compensation than the other approaches used for solving the harmonic related problems. The performance of the SAPF depends upon different control strategies. This paper present three-phase active filter to improve power quality. The active power filter (APF) is implemented with PWM based current controlled voltage source inverter (VSI). This VSI switching signals are generated throughl hysteresis current controller (HCC). The hysteresis band current control”

Keywords: Voltage source inverter, Shunt active filter, hysteresis current controller