根据摩擦因数随摩擦副表面温度的改变,研究了摩擦因数在电控机械自动变速汽车重复起步过程中的影响。建立了AMT起步时离合器传递转矩和压盘表面温升的模型。根据试验结果,采用"快—慢—快"起步控制策略,利用Matlab/Simulink进行汽车重复起步仿真,进行了摩擦副滑摩功仿真计算。仿真结果表明,摩擦系数随滑摩功的变化而变化,重复起步多次后,摩擦系数变得很小,相应离合器传递的转矩也变得很小,离合器主、从动盘一直处于滑磨状态,无法完成正常起步。
Based on the fact that friction coefficient changes with the friction surface temperature, the influence of friction coefficient on automatic mechanical transmission (AMT) is studied during repeated starting process. A model is established for the transmitted torque of clutch and the temperature rise on clutch plate surface during AMT starting. Based on the launching control rule of "fast-slow-fast", the repeated starting for AMT and the friction work of the friction pair are simulated. The simulation results show that friction coefficient changes with the change of the friction work. After several starting, friction coefficient and the transmitted torque of clutch diminish a lot, and the slipping between drive plate and clutch plate always exist, therefore,the vehicle can't start.