Current control of voltage-type PWM rectifier introducing resonance-based controller

A new current control method for voltage-type PWM rectifiers is proposed. To eliminate the steady-state deviation of the AC input current from its reference, a current controller is introduced which has a transfer characteristic similar to that of an LC resonant circuit whose resonant frequency is equal to the supply frequency. In addition to this controller, a proportional controller is used to improve the transient response of the AC input current. A set of optimum gains of the proposed controller is determined from stability analysis based on the root locus method. The effectiveness of the proposed control system is confirmed by experimental investigation of a test power converter system.