Performance Analysis of Shunt Active Power Filter with Different Switching Signal Generation Techniques

The performance of shunt active power filter (SAPF) is compared for steady state load condition. The SAPF is used for harmonic compensation of single phase ac/dc converter feeding a nonlinear load. The process involves an injection of equal but opposite current to mitigate the distortion current supplied back by nonlinear load to the voltage supply. Thus, the injected current will shape the supply current to a sinusoidal phase with the supply voltage. The techniques which are considered for comparative study are Hysteresis Current Control (HCC) and Sinusoidal Pulse Width Modulation (SPWM) technique. Performance analysis of above two switching signal generation based on percentage (THD) Total Harmonic Distortion, complexity speed of response, switching frequency and delay time in MATLAB. After simulation we can analyze the different results on above two methods based on given parameters of SAPF. The percentage THD of supply current reduces as per IEEE519 standard. HCC is simple in implementation over SPWM technique. The speed of response of both controllers is same. The switching frequency of HCC is variable but the SPWM technique operates fixed switching frequency. This is done by injecting equal but opposite current to shape the pulsating supply current to a sinusoidal form and in time phase with the supply voltage. Consequently, it would reduced input current distortion and achieve unity power factor when feeding a nonlinear load.