Research on Detective and Compensatory Method of Harmonic in Three-phase Asymmetry System

The detective method of harmonic is very important for APF.In order to eliminate the harmonic detection error caused by asymmetry of three-phase voltage,an improved harmonic current detective method is proposed.The proposed method is based on the research of the instantaneous symmetrical components combining with the second-order generalized integrator.The experimental results verify that the active power filter(APF) based on the detective method,can effectively detect and compensate harmonic current in three-phase asymmetrical system,and improve current waveform.