Abstract: In order to solve fluctuation problem of outputting active power of wind turbine generator in certain range caused by uncertainty of wind energy, a large inertia of wind turbine generator and response delay of wind turbine generating system, the paper proposed a novel active power smoothing control strategy for double-fed wind turbine generator. The control strategy adopts coordinated control strategy of variable propeller and variable speed in total wind speed range and on the basis adds a control link of active power error, which takes auxiliary controll dictates of rotor voltage as feedback variable to join into primary controlling dictates of rotor voltage to control SPWM pulse generator, so as to realize smoothing control of outputting active power of stator of wind turbine generator. Matlab/Simulink simulation results indicated that the control strategy effectively suppress fluctuations of outputting active power of double-fed wind turbine generator compared with traditional control strategies.