Dynamic Temperature Response And Experimental Research Of Two-Stage Gear Transmission System In Wind Turbine

Pollution and exhaustion of traditional energy sources such as coal and oil are the main problems that plague the sustainable development of today’s society.With the current changes in human activities and the country’s rapid economic development in recent years,the supply of energy from all walks of life is increasing.What follows is that the consumption of traditional energy is also increasing,many resources have been over-exploited,and energy problems will gradually restrict social and economic development.My country is currently promoting clean energy to replace fossil energy,and wind energy is now a renewable energy source that has attracted much attention.In the process of collecting and utilizing wind energy,how to make wind turbines operate continuously,stably and efficiently is of great significance for the development of wind energy resources and their effective and extensive application.Gear transmission system is one of the main components of the wind turbine generator set.The reliability of its work will directly affect the stable operation of the whole generator set,and it plays an extremely important role in the safety of the project.There are many ways to produce system failures.Among them,there are not a few cases of failures caused by gearbox overheating.For example,the transmission system of the wind turbine unit runs for a long time in the nacelle,and the duration is accompanied by instantaneous overload,and the rapid temperature rise of parts such as gears and bearings has caused the fire hazard of the unit.Therefore,the study of the dynamic temperature field of the gear transmission system has certain reference value for improving the design of the transmission system,the lubrication performance of the complete system,and the improvement of cooling efficiency.This article mainly focuses on the following research:First,the influence of the time-varying stiffness of gears and bearings on the entire transmission system is taken into account at the same time.The gear-shaft-bearing coupling model of the gearbox is constructed based on the principle of dynamics and finite element method and taking into account the flexibility of the shaft system.Then the dynamic parameters such as dynamic load and frictional micro-displacement during the operation of the system are solved.And parameters such as the heat flux density of each heat source and the heat transfer coefficient of each part of the system during the operation of the system are determined by combining the principles of tribology and heat transfer.After obtaining parameters such as heat flux density and convection heat transfer coefficient required for thermal analysis of the model,use finite element analysis software to simulate the temperature field of the transmission system model.At the same time,experiments are carried out under the same working conditions,and on this basis,the two sets of results are compared to modify the model and verify the correctness of the model.Finally,the influence of different dynamic characteristics on the temperature distribution of each part of the system is studied.The research shows that the temperature response of the transmission system including the dynamic characteristics is quite different from that under normal operating conditions.When the system is torsional resonance,the heat transfer rate increases and the temperature response increases sharply.The adjustment of the gear installation position can effectively improve the high temperature response,while the shaft bending resonance has little effect on the heat transfer and temperature response.