Based on the non-controllable AC/DC and controllable DC/AC configuration of permanent magnet synchronous wind generator（PMSWG）， a method of realizing its grid connection and maximal wind energy tracking by DC bus voltage control is proposed. The theory of controlling DC voltage by DC/AC decoupling power is analyzed. The direct grid-connected method by DC/AC charging DC capacity voltage is proposed， and the range of charging current and limit-current resistance is discussed. The relationship between the DC bus voltage and speed is analyzed. The DC voltage variable step disturbance is proposed to replace speed fix step disturbance. The proportion value of power variation's square is proposed as disturbance value. Simulation results demonstrate that the proposed control strategy is simple and effective and can be used for grid-connected PMSWG.