Harmonics Reduction of 3 Phase Diode Bridge Rectifiers by Implementing P-Q Theory with Active Filter

With the rapid use of power electronics devices such as rectifier, inverter etc. in power system causes serious problem with power quality. One among them is generation of current and voltage harmonics causing distortion of load waveforms, fluctuation in voltages, voltage dip, heating etc. Also presence of non-linear loads such as UPS, SMPS, drives etc. are the reason of current harmonics in power system. They draw reactive power components of current from mains causing disturbance in supply current waveform. Thus to avoid the consequences of harmonics we have to compensate the harmonics in power system. Among various methods used, one of the favourable way to compensate harmonics in power system is the effective use of Shunt Active Power Filter (SAPF). This research work gives detail performance analysis of SAPF with the help or control strategy of instantaneous active and reactive power theory i.e. “p-q theory�. Here we took 3 phase diode rectifier and simulation analysis is done to justify the method better over other. In this method a reference current is generated, which compensate harmonic current component in power system and THD of the source current is reduced. And system performance enhanced.