Current control of active power filters assisted by three-state hysteresis

In this paper, repetitive control is employed to design the current controller of active power filter for reducing the steady-state error due to periodic command. Zero steady-state error for current harmonics is realized. Harmonic reduction and power factor correction will both be carried out by the proposed filter. Discussions on the design of the current and voltage control loops are given. Experimental results verified the feasibility of the proposed method, obtained from a 10KW shunt active power filter.