Optimization Design And Fatigue Analysis For Wind Turbine Tower

Wind power, with no pollution, renewable, mature technology, has been widely generalized and applied in the world. As the major loading structure, tower weights much more than100tons, and accounts for more than eighteen percent of the total cost of wind turbine. Therefore, this paper presents researchs on optimization design of wind turbine tower based on the structure design theory, which is practical worth.Turbine tower can be simplified a variable cross-section cantilever, the deflection of which was calculated by conventional solution, that needs to provide method of solving the double interal and is very tedious. Thus. Moire integral method is proposed here and combined with compound trapezoidal formula to solve the deflection of tower, which laies the foundation for optimization design of tower.Considering much higher manufactureing cost of turbine for tower weight, optimization design model of tower is developed. Objective function is tower weight, and the external penalty function is employed to transform constraint model to unconstrained problem. Under the rated wind speed load, a2MW turbine tower is optimized with improved particle swarm. Optimization result is obtained by MATLB and the tower weight reduces obviously rather than initial value. According to local stress concentration caused by opening door, first order method of ANSYS is used for optimization of opening door size to obtain minimum concentration stress. Optimization result shows the stress reduces by12%.A set of data, obtained by experimental simulation under different wind speed conditions, is made linear fitting by least square method to get the S-N curve of fatigue analysis of tower. Design load spectrum of tower is estimated by experience, and combined with Miner damage theory for life evaluation of tower. Analysis result shows service life of tower meets design constrain of turbine.The research in this paper provides good theory reference for design tower, and also enhances the design efficiency and decreases the manufacturing cost of turbine.