Individual Pitch Control Analysis Of MW VSCF Wind Turbine

In order to improve the power generation efficiency of the wind farm, wind turbinestand-alone power increasing wind wheel diameter is increasing, the current stand-alonepower of the wind turbine has generally reached1.5MW,2MW,3MW and5MW,6LeafMW development, the length of the blade has been increased to40~60m. Becauseof wind shear and tower shadow impact on wind turbine.those addition load impace thewind turbine transition fatigue and wind turbine life. this dissertation research how toreduce tilt load and yaw load by individual pitch control. This control give analysismethod reduce load of wind turbine.This dissertation take the loads as the control object based on wind turbine systems,to design their control strategies. On the basis of building the model of wind turbineaerodynamic performance algorithm and the model of wind turbine,researched thecontrol strategies about pitch control aboved rated wind and researched to reduce theloads. Applied the proposed control strategies and methods design simulation model ofaerodynamic and individual pitch control system based on Matlab/simulink.The main work of this dissertation is as follows:In chapter1:introduced the research background and research and meaning,summarized research works of wind turbine, especially analysed the control strategiesand control algorithms, then introduced the main work and structure of dissertation.In chapter2:By considering the effects including the effects of wind shear, towershade and three-dimensional rotation, an improvement of the classical blade elementmomentum(BEM)theory was presented and a model for wind turbine aerodynamicperformance algorithm. Thrust, generator power and aerodynamic power coefficientwere numerically analyzed for various conditions of wind speed, rotor speed and pitchangle. The numerical model and results were verified by comparing with the results ofblade, a well-known software for wind energy design and analysis.In chapter3: introduced the wind turbine model of aerodynamic linearity, Based oninverse transformation, this dissertation build linearity model of wind turbine, and thecalculated method of wind turbine aerodynamic paraments.In chapter4:Investisgated the entire model of wind turbine facing control systemdesign. Based on module design concept, introduced the function model of wind turbinetransmission and pitch actuator, and introduced their working principles and operation characteristics in great detail. based on Matlab/simulink, This dissertation build windmodel. Compareing the control method and the result of individual pitch control basedon amiuth angle with the control method of individual pitch control based on blade load.Simulation results of the proposed control strategy can reduce the tilt load and yaw loadof wind turbine, comparing with collective pitch control.In chapter5: this chapter research the control method of wind feed foward-loadfeedback. Simulation results of the proposed method strategy can rapily reduce the tiltload and yaw load of wind turbine. the control method of wind feedfoward-loadfeedback. Individual pitch control can reduce tilt load and yaw load. So the advantageof this control strategy reduce the load combining the feedfoward and feedback controlstrategy, achieving the expect result.In chapter6: conclusions are given along with recommendations for the futureresearch.