To improve the performance of multi-function photovoltaic inverter, a novel design method of the inner loop current controller based on robust H∞ control theory is proposed. Firstly, the state space model of the inner loop control system of LCL inverter is established in the static coordinate system. Then, based on this state space model, detailed analysis of the design process is carried out. Finally, the effectiveness of the designed repetitive controller that can track the given current accurately is verified through a PSCAD simulation model.