Optimal design of repetitive controller for harmonic elimination in PWM voltage source inverters

This paper presents an analysis of the application and optimal design of the repetitive controller for eliminating harmonic distortion in pulse-width modulation voltage source inverter systems. A method of analyzing the repetitive control system from the frequency response viewpoint is introduced. Based on this method, a systematic way of optimizing the design of the system is proposed. Specifically, the closed-loop repetitive controller is modified by including a zero-magnitude-and-phase compensator and a lead-lag compensator to improve the stability and tracking accuracy of the inverter system. It is shown both analytically and by simulations that the harmonics in the inverter's output voltage can be effectively eliminated with the improved repetitive controller.