PI_ Repeated Control of Three-phase Grid-Connected Inverter

Aiming at the problems of high harmonic content and large steady-state error that are common in three-phase grid-connected inverters, this paper studies the control method of output grid-connected current. Based on the traditional PI control method and the repetitive control method based on the internal model principle, this paper proposes to cascade PI control and repetitive control to realize PI_The repetitive control method. It can not only make the system respond quickly, but also reduce the steady-state error and harmonic content of the grid current. With the help of three-phase grid connected inverter, this paper uses Matlab / Simulink for simulation, and compares PI-repetitive control with PI control to illustrate the superiority of PI-repetitive control.