Variable Pitch Tracking Control for a Wind Power System Based on Feedback Linearization Theory

A mathematical model of second-order for a doubly-fed induction wind generator was established to deal with the problem of inconstant output of the wind generator when wind speed is higher than the rated wind speed. According to the feedback linearization and the optimal control theory, the presentation of the state feedback linearization control law was given. In addition, the optimal tracking controller was designed on the basis of the definition of tracking errors. By using Matlab/Simulink software as a simulation platform, the correctness and efficiency of the designed controller was verified. Comparing with traditional PI control, no matter what changes the wind speed has, the proposed optimal controller is able to better keep the output basically constant and behave robustly.