Against the problem of low voltage ride through of permanent magnet direct-drive wind power generation system, improving the traditional control strategies, increasing feed forward compensation control in the machine side, depending on the power difference of between the motor and the grid side to adjust motor-side active current quickly to control the torque of the generator, achieving active power control of the generator. Grid-side converter tracks the grid voltage, outputs a constant reactive power according to the dropped level of the grid voltage to support grid voltage recovery. The simulation showed that, the improved control strategy can stable the DC bus voltage quickly, can achieve low-voltage ride through operation of wind turbines.