A novel current regulation scheme for boost type PWM rectifier based on iterative learning control

Current regulation is very important for high-performance PWM rectifiers. Proportional integral (PI) regulator in synchronous reference frame is generally viewed as a standard solution for the current regulation problem. However, such an approach results in a complicated control scheme under unbalanced input voltage conditions which would required the tracking of unbalanced currents. This paper presents a novel current control technique for the boost type PWM rectifier. The proposed hybrid control scheme consists of a proportional controller together with a plug-in type iterative learning controller (ILC). A zero-phase low-pass filter is introduced in the scheme to eliminate the high frequency noise and unwanted high frequency dynamics. The detailed design procedure for proportional controller and iterative learning controller are discussed. Simulation results show that the proposed control scheme can achieve good performance during steady-state as well as dynamic operations. Experiment results are also presented to show that introduction of the ILC effectively improves the tracking performance.