A novel control method of PAPF for harmonics compensation and resonance damping in power system

When applying parallel active power filter (PAPF) to the power transmission/distribution system that contains the reactive power compensation capacitors, the capacitors can influence the system stability and the compensation performance of PAPF. In this paper, considering the influence of capacitors, the harmonics compensation and resonance damping characteristics of PAPF with traditional load current detection methods are analyzed. The analysis results show that, when capacitor current is not included in the detected load current, PAPF has ideal performance of load harmonics compensation and parallel resonance damping, but has no effect on damping series resonance and compensating harmonic current caused by supply voltage distortion; when capacitor current is included in the detected load current, PAPF with traditional control method can´t work stable. To improve the system stability and the performance of PAPF, a novel control method of PAPF is proposed. With the proposed control method, PAPF has excellent performance for harmonics compensation and resonance damping. Finally, experiment results are presented to verify the analysis.