Repetitive control of grid current based on parameter self-adapting

When the fundamental frequency is shifting, it´s hard for traditional repetitive controller to work at the resonant frequencies. In this paper, a novel self-adaptive repetitive controller is proposed to suppress the current harmonics. This controller can adjust the sampling times in the grid cycles based on a special self-adaptive control algorithm. Mathematical analysis, simulations and physical experiments have validated the effectiveness of the self-adaptive repetitive controller.