Study On Simulation Andevaluation Method Of Dynamic Characteristics Of Gear Transmission System Of High Speedtrain

With the rapid development and popularization of high speed trains in china, the acceleration of the operation speed of trains leads to more severe vibration of the train component, such as gear transmission system. Especially in recent years, problems such as crack of gear box, gear wear or bearing failure, make the operation safety of gear transmission system of train become a focus of research. The traditional vehicle dynamics analysis mainly focus on the vehicle body, the frame or the wheelset, and pay less attention to the other key parts of the train. Besides, there is no relevant standard for evaluation of the vibration of the gear transmission system of train. In this context, this paper studies the dynamic performance and vibration evaluation of gear transmission system of train. The main contents are as follows:Firstly, introduced the structure and driving mode of gear transmission system of train. And based on the theory of gear system dynamics, analyzed the vibration mechanism and common failure modes of the gear system are analyzed, and established the dynamic analysis equations. Besides, in view of the particularity of gear system used in high speed train, the internal and external incentive factors are introduced and analyzed in detail.Secondly, a rigid multi-body model of high speed train is established by using S1MPACK, in which the gear system especially the gears is accurately modeled. The traction and resistance moment are applied to the corresponding gear based on the characteristics of the traction and resistance of the train. On the basis of the model, obtained the dynamic characteristics of gear transmission system of train by using simulation, and the influence of gear transmission system itself or the gear meshing characteristics on the dynamic performance of the train is analyzed.Then, using ANSYS and SIMPACK for joint simulation, the modal analysis and substructure analysis of gear box are carried out. and a multi-body vehicle dynamic model which contains the flexible box is established. The dynamic responses characteristics of the flexible box and the rigid box are compared, as well as the influence of vehicle are analyzed. Besides, the relationship between the wheel polygon and the resonance of the flexible gear box body is also analyzed.Finally, a method based on kernel density estimation and measured value of vibration of gear box is proposed, which could evaluate the vibration of gear box by setting up a "gear box vibration threshold database" and a "gear system fault characteristic frequency library". And the method can be applied to the real time detection for the vibration state of the gear box, which could give fault alarm prompt at the early stage of the fault of the gear system, and the possible form of failure can also be judged to ensure the safety of the train.