An improved control method for three-phase active power filter

In this paper a three-phase active power filter with an improved control method is described in detail. Its main circuit topology adopts the three-phase four-wire voltage-source converter with split-capacitors. The control circuit generates current references for main currents to follow with a dynamic hysteresis-band current controller. The proposed active power filter may provide the following multifunction at the same time: reactive power compensation, harmonic suppression, and current balance in three-phase power system. Experimental results prove that the control method has the following features: simple control circuit, high system reliability, and good ability of reactive power compensation, harmonic suppression, and current balance.