According to the limitation of traditional PI control, a new control strategy to control threephase inverter was proposed, which was formed by proportional complex integral (PCI) control and repetitive control in parallel. Proportional complex integral (PCI) control could eliminate the steadystate error in a given condition; repetitive control could suppress the harmonics of gridconnected current and improved the accuracy of steady state control. The new control strategy could be used to control the AC signal and could be directly applied to the threephase abc coordinate system. Without coordinate change, it could save the cost of the inverter control system. On the basis of MATLAB/Simulink platform, a model of gridconnected inverter with LC filter was established and the results of simulation were analyzed to verify feasibility of the strategy.