Improvement of the time domain specifications of dc bus voltage of shunt active filter using controllers

摘要

In power system, the nonlinear load affects the power quality such as harmonics of the supply system. In this paper, the diode rectifier is used as load which distorts the supply current. This supply current harmonics are reduced by the Shunt active filter (SAF) which injects the harmonic current to the load. So supply is free from harmonics. The synchronous reference frame theory is used to extract the fundamental component of the supply current which is the reference current for the hysteresis controller. The hysteresis controller tunes the SAF so that it generates the current equal in magnitude and opposite in phase with the nonlinear load. So the total harmonic distortion (THD) of supply current is greatly reduced. In this paper the SAF dc bus voltage is maintained constant using PI / PID controller and time domain specification of the bus voltage is analyzed using Matlab simulink and the results are presented.