Abstract
Aiming at the resonance problem in the process of grid connection of LCL filter microgrid inverter, a multi-resonance LCL harmonic suppression strategy is proposed. On the basis of analyzing the principle and establishing the mathematical model in detail, the realization process of the multi-resonance constant power compound control strategy is studied emphatically. Through the simulation, the validity of the control strategy is verified, The results show that the scheme stabilizes the output power and reduces the total harmonic distortion of the grid-connected inverter to 0.12%, and the corresponding phase current distortion rate drops to 0.02%.The suppression effect is obvious, it is an effective harmonic suppression method.