Study On Intelligent Control Of Variable-pitch Variable-speed Wind Turbines

Energy and environment are pressing problems that must be settled by human beings for future survival and development. As an important kind of generating form, wind power generation not merely can save the routine energy resources, but also may decrease pollution of the environment. Thus it can bring preferable economic benefits and community benefits. At resent, wind power generation has caused more and more concern by governments all around the world.Because of wind energy has lower density, instability and randomicity, wind turbines have strong nonlinear multivariable with many uncertain factors and disturbances. Therefore control is crucial to the efficiency and reliability of wind turbines. Compare with traditional control tactics, wind power generation system can gain satisfactory results with application of intelligent control theory.This paper has mainly studied the novel variable-pitch variable-speed wind turbines and Yaw-control system of wind turbine generator. First, the modeling of the major variable-pitch variable-speed wind turbines is established and intelligent control strategy of variable-pitch variable-speed wind turbines is designed. Then, different fuzzy controller is designed by different wind velocity condition. At below rated wind speed, the controller can capture maximum wind energy. At above rated wind speed, it can keep rated output power of wind turbine. Simulation study shows that wind turbine can capture maximum energy during large wind variation and the control system has good abilities of real time and robustness. Second, this paper propose a new staged composite control method combining traditional PID and fuzzy control for yaw system, it not only is able to inherit the low error and good static stability of routine PID, but also has fuzzy control's advantage of fully acclimatizing itself to the object. The staged composite control method can meet the requirement of the yaw system, and get good result by MATLAB simulation. At last, hardware controller of Yaw-control system is designed. Because working condition is bad, measures to avoid interference are also designed.