Power quality enhancement using a new hybrid active power filter under non-ideal source and load conditions

Harmonic and reactive power compensation are important power quality problems. In this paper a new hybrid power filter is proposed which consists of a series tuned passive filter and small rated shunt active filter. Passive filter is tuned at fifth and seventh order harmonic frequencies. At this frequencies passive filter impedance is high which blocks them to appear in utility side. Consequently active filter compensates for third and higher order harmonics, unbalance current and reactive power under non-ideal source voltage condition. A new control method based on PHC strategy in d-q frame is presented for active part. The proposed system was simulated using Power System Blockset (PSB) Toolbox of Matlab. The simulation results show considerable decrease in active filter rating in the proposed hybrid structure and good performance of hybrid filter under load and source voltage perturbation simultaneously.