| Energy and environment are pressing problems that must be settled by human be-ings for future survival and development. Wind power has preferable economic and so-cial benefits because of its cleanliness and free pollution, short construction period, flexible investment and few occupation of land. At present, there are big gaps between china and developed countries in wind turbine's theory and application research, be-cause wind power has disadvantage with thermal power and hydropower in cost, power quality, equipment manufacture and control technology. Research of wind turbine in china is very weak and many advanced wind turbine technologies are not solved such as high power capacity, pitch control and variable speed constant frequency etc. Thus, al-most all advanced large-scale wind turbines are imported from overseas. In all, in-depth research of wind turbine technology has very important meaning for persistent wind turbine development and home production.Wind turbine is a comprehensive system engineering of high technology which deals with aerodynamics, automatic control, mechanical drive and generator etc. The research difficulties and hot pots of wind power are focused on high power capacity, advanced reliability,high efficiency and low cost etc. Optimum design and control strategy are crucial to the efficiency and reliability of wind turbines. The wind turbines operate in execrable environment, in which wind is transient and variable. The wind turbine is a complicated nonlinear uncertain system. So the modeling and analysis of system is crucial to the system design of wind turbines. This dissertation does some prophase researches on the important project of Chongqing city system design of wind turbines in advance, which ranges from aerodynamics theory, nonlinear mathematic model, and structural dynamics to control strategy. Main contents can be concluded the following:①Researches on aerodynamic theories and methods. The aerodynamic theories are crucial to the modeling and analysis of wind turbines, the usual methods used is bladed element theory (BEM theory), which cannot take the time lag into consideration caused by the air mass. Aiming at the shortcoming of BEM theory, the theories applied to the aerodynamics of helicopter, Pitt-Peter theory and GDW theory are introduced to calculate the rotor aerodynamics. The two theories are modified based on the rotor characteristics after studying the difference between the wind rotor and helicopter rotor. The calculation methods for rotor aerodynamics based on the two theories are put for-ward, which are programmed in Matlab simulink. 600KW wind turbine is researched on rotor aerodynamics, which results are compared to the results calculated by Bladed. The comparison shows that the modified theory can be used to the aerodynamics analysis of wind turbine and more correct than BEM theory.②The nonlinear model is established to describe the dynamic characteristics of drive train system of wind turbine。The layout of drive train mostly used in international market are studied and summed up. The model is based on the IEC regulation, which is programmed in Matlab simulink. 600KW wind turbine is researched on system per-formance, which results are compared to the results calculated by Bladed. The com-parison shows that the modified theory can be used to the system analysis of wind tur-bine.③Combine simulation on structural dynamics of wind turbine。Because the usual method cannot take the coupling relation between the rotor structure and aerodynamic load, in which the correctness will be influenced. Aiming that problem,the combine simulation is used in this dissertation, which can take the coupling into consideration. 600KW wind turbine is researched on rotor structural dynamics, which results are com-pared to the results calculated by Bladed. The comparison shows that the modified the-ory can be used to the structural analysis of wind turbine. But the simulation will cost much time, the ANN is used to predict the structural dynamics of wind turbines after calculating sample using combine technology. The result shows that ANN combined with simulation can reduce the time and ensure the correctness.④The model established in the dissertation is used in the analysis of control strat-egy of wind turbine。The four control strategies used commonly are studied and summed up based on the study in the wind maximum capture principal. 600KW wind turbine is researched on different control strategy. The result shows that the wind tur-bine using variable pitch control strategy can produce better power than the one using other strategies. The analysis shows that the model can be used to the analysis of per-formance and control strategy.
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