Improved maximum power point tracking strategy of doubly-fed wind generator

In view of problem that traditional extremum seeking strategy of maximum power point tracking of doubly-fed wind generator takes sine signal as seeking signal, and the sine signal is difficult to be distinguished from output signal, the paper proposed an improved maximum power point tracking strategy which uses wind turbulence as extremum seeking signal. The improved strategy makes Fourier transform for blade top speed ration and power coefficient to obtain phase difference information, so as to determine change direction of blade top speed ration to make doubly-fed wind generator reach the best running point. The simulation result shows that the improved strategy can control rotational speed of wind generator to track change of wind speed well and realizes maximum wind energy capturing in running region under rated wind speed.