The traditional PI control of AC signal results a certain steady state error commonly. Under this background, a new strategy is proposed based on the fuzzy PCI control which is in parallel with a PR control. It controls the gridconnect process of the threephase inverter directly. The fuzzy PCI control can eliminate the steadystate error under given conditions and track AC control variables accurately. The PCI proportional coefficients and ratio coefficient are adjusted online according to error and error rate. In view of the advantage PR control which has an infinite gain at the resonant frequency, the PR control is added to make the system meet the requirements of the gridconnected. The proposed compound control strategy can be utilized to control the AC signal and can be directly applied to the threephase ABC coordinate system without a coordinate change. The cost of the inverter control system is saved. Lately, a model of gridconnected inverter with LC filter is established on MATLAB/Simulink and the feasibility of the strategy is verified.