Dynamics Research Of Megawatt Level Wind Turbine Drive Train

The research subject of the thesis stems from the project “The study of key technologies of industrialization for 7M W wind turbine gearbox and spindle bearing” in the National Science and Technology Pillar Program during the Twelfth Five-year Plan Period of China.Wind turbine drive train, which is a complex elastic system, is mainly consisted of hub, main shaft, gearbox, flexible coupling and generator, etc. And wind turbine drive train is always working under harsh environments such as time-varying wind load and flexible supporting. Dynamics of wind turbine drive train have a deep impact on the reliability of the entire turbine. Recently, high failure rates of wind turbine drive have made it become the weakness of the wind turbine, which deeply prevent wind turbine from achieving its 20-year design life. Research on the dynamics of wind turbine drive train has great practical engineering values.The main contents of this thesis are shown as follows:① The formulation and transmission principle of the multi-megawatt wind turbine drive train is analyzed. The components and coefficients of the wind turbine drive train are introduced.② The multi-rigid-body modelling theory of wind turbine drive train is analyzed and then to obtain the coordinate system, coordinates of drive train components, and shift of each drive train components to deduct kinetic energy, potential energy, dissipation energy of drive train system. Eventually the dynamic equations of the wind turbine drive train are deducted with Lagrange method. Based on the theory mentioned above, the multi-rigid-body dynamic model of wind turbine drive train is built using SIM PACK.③ The multi-rigid-body dynamic model of wind turbine drive train is computed to obtain the first 9t h orders of mode frequency and mode shape of wind drive train. The modes of the drive train are obtained with this computational model. Based upon the direct integration method, the dynamic response of the drive train dynamic model is computed under rated working condition and the dynamic characteristics of the wind turbine drive train are analyzed.④ The remote on-line testing system of multi-megawatt wind turbine drive train is built to test the dynamics of the drive train performing in the wind field. The results of real wind field test validate the theoretical model.