The Design Of Pitch Control System For Large Scale Wind Turbine And The Research On Its Intelligent Control Method

Energy and environment have been the chief issue facing humanity in the twenty-first century. Wind energy is being attached great importance to all over the world because of its advantages: renewable, non-polluting, low-cost etc. R&D of wind power system has been a hot and difficult point in energy technology field. Since wind energy has the characteristics of lower density, random, instability and so on, it is of great realistic significance to make a deep study in control technology of wind turbines especially in large scale sets. Based on the domestic megawatt wind turbine generator system, the pitch control techniques for large scale wind turbine are deeply analyzed in this thesis.Launching on the basic theory of wind turbine blade aerodynamics, this thesis puts forward the essential regulations of pitch control. Individual pitch control is the inevitable trend of pitch control. Referring to related information at home and abroad, a design of hydraulic system for individual pitch control is proposed, including theoretical calculation, analysis of hydraulic scheme and the selection of units etc. The 3D solid of individual pitch-regulated actuator is modeled using Pro/Engineer, and the mechanism operation is animated subsequently. In order to study the dynamic characteristics and control regulations of pitch control system, the mathematical models of wind turbine parts are analyzed and expressed as simulation modules in MATLAB/Simulink.Intelligent control technology is increasingly applied in the field of industrial control. This thesis brings forward with a design of fuzzy PID controller based on self-turning parameters for collective pitch control (CPC), and prove that the adaptability and reliability of fuzzy PID are much better than traditional PID by simulation. In addition, a control strategy of individual pitch control (IPC) based on inflow angle prediction is put forward , using neural networks. And it is concluded that IPC can effectively reduce the aerodynamic fatigue loads on blades, and its effect of power control is better than CPC, by means of simulation.