Adaptive hysteresis current controlled Shunt Active Power Filter for power quality enhancement

Wide spread use of power electronic devices in the present scenario has led to severe harmonic pollution, affecting the quality of power. The main focus of this article is to investigate the effects of adaptive control on the switching frequency and Total Harmonic Distortion (THD) of the Grid Interactive Inverter in a Shunt Active Power Filter. Reference current generation is done using synchronous reference frame based algorithm. Drawback of variable switching frequency in conventional hysteresis controller is overcome by adaptive control which maintains the instantaneous switching frequency low and nearly constant. Adaptive control optimizes the switching frequency of the inverter and the Total Harmonic Distortion of source current maintaining it within the limits specified by the standards. This facilitates reduction in switching losses which would have increased if high switching frequencies were used for the inverter of the shunt active power filter.