A practical series hybrid active power filter based on fundamental magnetic potential self-balance

In this paper, a novel series hybrid active power filter based on fundamental magnetic potential self-balance is proposed which consists of three parts: a passive power filter, an active power filter and a series current converter. A LC fundamental series-connected resonance branch is connected in the second side of current converter, then the current converter presents low reactance to fundamental and high impedance to the harmonics, and the harmonic voltage is measured by the detecting winding of the current converter. The active power filter is controlled as a harmonic voltage source. Where, the active power filter is connected to the passive filters in series through a transformer. The system configuration and compensation principle of the hybrid active power filter are addressed. The voltage control scheme and the harmonic voltage detecting method are analyzed. The validity of novel principle and excellent filtering characteristic are verified by the experimental and simulation results.