中文摘要：

针对大型风力发电机组齿轮传动链动态刚度引起的机组结构振动问题,综合轮齿弯曲变形、齿根过度圆角处的基体变形和接触变形等因素,建立齿轮时变啮合刚度的量化分析模型,并与有限元动态啮合模型对比验证理论模型的正确性。在此基础上考虑齿轮时变啮合刚度和轴扭转刚度推导1.5 MW风力机传动链的动态总刚度,用于分析传动链在动态刚度下固有特性变化规律及传动链临界转速对动态刚度参数的敏感性,量化显示动态刚度幅值变化引起的临界转速波动。研究表明,齿轮时变啮合刚度的波动会引起传动链临界转速的不稳定,增大时变刚度幅值会引起转子系统临界转速的升高,但总体上啮合刚度波动对临界转速的影响处于非敏感区。本研究对揭示风力机齿轮传动链的内部刚度激励机理和实现系统动态性能优化设计提供理论依据。

英文摘要：

Aiming at the structural vibration problems in a wind turbine caused by the dynamic stiffness of the drive-train system,aquantitative analysis model with time-varying gear mesh stiffness is established that takes into account tooth bending deflection,fillet-foundation and contact deflection.Then,in order to verify the method′s validity,the calculation results of analytical modeling are compared with the simulation results of the dynamic meshing model with a finite element method.On this basis,when considering the time-varying mesh stiffness and shaft torsional stiffness,the dynamic stiffness matrix of a 1.5 MW wind turbine drive-train system is deduced and used to analyze the regular pattern of inherent characteristics and the sensitivity of the critical speed to the dynamic stiffness parameters.At the same time,it quantifies the critical speed fluctuation caused by changes in the dynamic stiffness amplitude.The results show that the instability of the critical speed of the drive-train system appears when the gear varying mesh stiffness fluctuates,and the critical speed of the rotor will increase since the amplitude of the time-varying stiffness is significantly higher.However,the critical speed of the drive-train system is insensitive to time-varying stiffness.This research can improve understanding of vibration characteristics and provide a reference for the optimal design of structures.