Dynamic Characteristics Of Planetary Gear Transmission System For 2.5MW Wind Turbine Speed Increasing Box Under Varying Wind Load

The speed increasing gearbox is the key component of the wind turbine, which must have higher mechanical properties than the general mechanical system because of influencing by the random wind and working in the environment of high altitude setting up. The planetary gear transmission system increasing gearbox of 2.5MW wind turbine has characteristics of low speed, heavy load, varying speed and varying load. Due to the time-varying disturbance under the random wind, it has very complex dynamic characteristics. Researching the dynamic properties of planetary gear transmission of wind turbine can lay a good foundation for fault diagnosis and optimization design about gearbox and can make sense for improving the reliability and service life of wind turbine.The thesis focus on the planetary gear transmission system of 2.5MW wind turbine, which set up the dynamic model and analyze the inherent characteristics and dynamic response characteristics of planetary gear transmission system. The main research contents as follows:(1) Dynamic model of 2.5MW wind turbine planetary gear transmission system is built. Considering the internal excitations such as the time-varying meshing stiffness and bearing stiffness, a dynamic model is set up by using lumped-parameter method.(2) The analysis of inherent characteristics about 2.5MW wind turbine planetary gear transmission system. When calculate the inherent frequency and inherent mode of vibration, compared under the conditions of three planetary gears have the same average mesh stiffness with having different mesh stiffness which were influenced by meshing phase, the difference of inherent characteristics can be distinguished, then the effects of meshing phase on inherent characteristics can be obtained.(3) The effect of external random wind load on dynamic response of 2.5MW wind, turbine planetary gear transmission system is analyzed. A random wind model basing on the two parameters Weibull distribution is built, The vibration displacement and vibration velocity of components in system which are influenced by time-varying input torque are got, and the dynamic response characteristics of planetary gear transmission system under varying wind load are studied. The research results can lay a good theoretical foundation for fault diagnosis and optimization design about wind turbine gearbox.