Minimally Switched Shunt active Power Filter Inverter for Harmonic Mitigation

Active filters provide significant harmonic and reactive power compensation and are thereby widely accepted as devices for power quality enhancement.. Many research works have been done to improve the dynamic performance of active filters. Current research work focuses on implementing a Minimally Switched Shunt Active Power filter for power quality enhancement. Minimally switched grid interactive inverter is fed from a modified constant frequency hysteresis controller in which only two switches of the inverter are controlled at any instant of time. Different from the previous related works I cosΦ algorithm is used for reference current generation in this work. Pulses from a conventional hysteresis controller are processed based on a switching algorithm to reduce the switching losses to onethird. In the current work switching frequency is made constant by subtracting a high frequency triangular signal from the reference signal generated. The paper is simulated using MATLABSIMULINK. Source Current THD is significantly reduced and is well within the 5% limit specified by the standards.