H∞ robust control for VSCF brushless doubly-fed wind power generator system

Due to the randomicity and instability of the wind energy, the wind power generation system has some robust control problems, such as the parameter uncertainties, disturbance rejection, imprecise model, and so on. Based on the analysis of the wind turbine operation characteristics, the generator speed has to be rapidly adjusted with the wind speed changing to capture the maximum power. For the variable speed constant frequency (VSCF) brushless doubly-fed wind power generation system, a speed controller is designed, using the H_infin robust control theory without the orthogonality assumption conditions to settle the conservatism. The proposed controller enhances the robustness of the system to the parameters uncertainties and the rapid tracking performance to the input signal. Thereby the rapidity and stability of the maximum wind energy tracking are achieved, and the generation efficiency is improved.