Design and Research on Active Power Filter in Three Phase Four Wire System

With the development of the electronics, harmonic problem became more serious. The paper presents the novel active power filter (APF) of three phase four wire system base on three phase four legs converter. The electrical parameters of APF is analyzed, and this paper give the design method. The harmonic current detection and pulse width modulation strategy of the APF are presented in this paper. Finally, the APF performance is validated by simulation and experiment.