Study Of Variable Pitch Control Strategy Of Wind Power System

With the shortage of energy and the seriousness of pollution, wind has gained more attention as a kind of renewable resource, and Wind Power has developed quickly. But because of the random of the wind and the effect of pneumatic, wind turbine is nonlinear, it is hard to be controlled exactly by traditional controllers. It is very important to control the system whole and introduce advanced control theory.The main purpose of this study is to design the variable pitch controller, and make the output power constant when the wind speed is higher than the rated. Firstly, the status of wind power and control technology were discussed in the paper. A wind turbine model was made in chapter II and the results of wind power system to the open-loop simulation were given to explain the importance of pitch control. In Chapter III, exact linearization theory was used to build a linear model of the overall situation. Chapter IV raised the study of variable pitch control of wind power, then designed controllers based on optimal theory, H_∞, robust control, fuzzy control theory, sliding mode variable structure for the linear model built in Chapter III, then combined these controllers with coordinate transformation and state feedback selected, and resulted with variable pitch controllers of the original wind power system. In the final, this article summarized the issues and prospected the study in future.