| As a kind of clean and renewable energy utilization, wind power generation has experienced rapid growth in recent years in the world. Variable speed constant frequency (VSCF) wind power generation technology becomes the main stream of the research area for their exclusive advantages. With the support of the National Science Foundation of China Project (50677021)-Research on optimizing control strategy overall operating condition for variable wind turbine hybrid system, Ministry of Education Important Project (105049)-Research on advanced control technique for large-scale wind turbines and the key construction project for the 3rd stage of the 211 project- physical experiment platform and software simulator of wind power generation. This thesis studies the modeling and control method of the four main parts of VSCF wind power generation system - wind turbine, generator, converter and drive train. Primary contents and original contributions of this thesis can be summarized as follows:Firstly, the variable pitch wind turbine model is built based on blade element theory, velocity revise method of trailing vortex and blade element division method according to weight coefficient. Considering wind shear and tower shadow effect the wind turbine model is corrected future. The new model not only has airfoil adaptability but also in more accordance with practice.Secondly, operation function, equivalent-circuit model and steady-state phasor diagram of DFIG are analyzed. On that basis a method of using space vector theory is applied to set up the space vector model of the DFIG. According to the space vector model of DFIG a whole model of pitch-controlled variable-speed WECS (wind energy conversion system) is set up. By comparing the phase angle of stator and rotor MMF (Magnetic Motive Force) space vector of DFIG with AC excitation or without AC excitation, the electromagnetic essence of AC excitation is revealed.Thirdly, operating field and control target of VSCF wind power generator are analyzed in detail. The principle and method of cut-in control, maximum wind power track control and pitch angle control are mainly expounded. A whole simulation model which can operate under various circumstances is developed and the corresponding operation curves are acquired. All the work above lays foundation for the software simulator of wind power generation.Fourthly, a hybrid system model is given for the excitation source of the double-fed induction wind power generator. The SVPWM modulation process of the converter is analyzed according to hybrid automata theory. Some important sets such as staying condition set, discrete state transition set and transition guards are acquired. A new analysis approach of the three-phase power electronic circuits through hybrid system theory has been presented. For the stability of DC bus voltage in the converter served for DFIG, a new fuzzy PID control strategy with parameters self-tuning is proposed based on the change rate of the rotor current space vector modulus value (dAir/dt). The simulation results show that the new fuzzy PID controller with parameters self-tuning has been greatly improved in reducing the fluctuation of the DC bus voltage.Fifthly, In order to minimize the fluctuations of steady-state operation point, a gain-schedule adaptive LQG control strategy based on effective wind speed estimation is proposed. The simulation results show that this control strategy is not only solve the effective wind speed estimation problem of three dimensional wind profiles but also realize the coordinate optimization of the wind turbine, drive train, generator, pitch actuator and alleviate the torque variations of the drive chain and smooth output power.Sixthly, a physical experiment platform of wind power generation is set up including the hardware and software design. The function of wind turbine character simulator is basically realized which lays foundation of VSCF wind power generation experiment.
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