Harmonics mitigation by using shunt active power filter under different load condition

Power electronics devices when connected to power system draw reactive power and causes harmonics. They cause distortion in current and voltage waveform, capacitor failure; resonance problem, power factor problems etc. In order to improve the performance it is highly required to eliminate the harmonics and compensate the reactive power in the supply system. Passive filters were used previously for reactive power and harmonics compensation but they have resonance problems, larger in size and effect of source impedance on performance etc. In this paper we design shunt active power filter (SAPF) by using d-q method which will eliminate the harmonics from power utility system and the reference current generate here continuously monitoring the reactive power flow and harmonics reduction from the distorted wave form.