Wear Analysis And Optimization Design Of The Synchronizer For Two Gear Transmission Of The Pure Electric Vehicle

The evaluation method of transmissions on traditional internal combustion engine is not all suitable for the pure electric vehicle transmission, and the relationship and influence between the synchronizer and its wear and the whole vehicle is often ignored in design. The synchronizer in guarantee smooth shifting should not be on the basis of some loss of dynamic performance and comfort of the vehicle, at the same time shift control strategy is also shall ensure that the wear of the synchronizer is not beyond the allowable range. This paper studied a type of two gears AMT which is in power and economy as a design goal, the purpose of this study is to analysis and optimization the wear of two speed transmission synchronizer for pure electric vehicles, and ensure the vehicle dynamic performance and comfort. In this paper, based on the relevant design theory of synchronizer and of running condition of vehicle, the key factors affecting the synchronizer wear are analyzed, and discussed how to reduce wear synchronizer considering the vehicle condition, main work includes:First of all, according to the related theory and structure of synchronizer, this paper discussed the relation of the parameters of the synchronizer and determine the initial values, which laid a foundation for optimization; Secondly, according to the evaluation index of synchronizer and performance constraint, the synchronizer parameters are optimized by using the fmincon function in Matlab, and the key parameters that affect the performance of the synchronizer and the main boundary conditions are determined; And then, the different evolution of the failure modes of the synchronizer from the shifting difficulty to non-synchronous impact caused by the change of the friction coefficient during the wear process of the synchronizer is analyzed, based on the relationship between the parameters of the synchronizer; Then the influence of the different parameters of the model on the performance of the synchronizer is analyzed by using Simulink to model and simulate the process of synchronization, and confirm the wear of the synchronizer is increased with the increase of the rotating speed; At last, this paper analyzed the influence of synchronizer performance on vehicle performance in combination with the vehicle dynamic simulation model, and the way to adjust motor speed can not only ensure the performance of the vehicle, but also improve the wear condition of the synchronizer to prolong the life of the synchronizer.