含齿侧间隙两挡变速器电动汽车传动系统扭振分析

Analysis of Torsional Vibration of Electric Vehicle Transmission Systems with Backlash

针对一款含两挡变速器的纯电动汽车,建立电机、电机轴、两挡变速器、变速器中间轴、变速器输出轴、主减速器/差速器总成、左右半轴、轮胎/车身等子模块模型,考虑常啮合齿轮副、一挡齿轮副、主减速器齿轮副的齿侧间隙,建立整个传动系统的非线性扭振动力学模型。运用MATLAB软件,采用龙格库塔法进行数值求解,分别对比分析不同齿侧间隙对常啮合从动齿轮、一挡从动齿轮、主减速器从动齿轮、整车的角位移影响,研究电机输出轴、变速器中间轴转矩响应特性和有无齿侧间隙的常啮合从动轮啮合扭矩响应特性。结果表明,改变齿侧间隙将影响传动系统的常啮合从动齿轮、一挡从动齿轮、主减速器从动齿轮、整车等的角位移、转矩波动幅度、频率,尤其是汽车电机启动前0.5秒时间段内齿侧间隙对这些传动部件的角位移、转矩波动影响更大,说明齿侧间隙的改变会使传动系统扭振现象也发生改变。

Sub-modules of the pure electric vehicle with a double-speed transmission were established,including the motor,motor shaft,double-speed transmission,transmission intermediate shaft,transmission output shaft,main reducer/differential assembly,left and right semi-shafts,and tire/body.Considering the tooth side clearances of the constant meshing gear pair,the first gear pair,and the main reducer gear pair,a nonlinear torsional vibration mechanical model of the entire transmission system is established.In virtue of MATLAB software,the Runge-Kutta method is used to get the nμmerical solution.The effects of different tooth side clearances on the angular displacements of the constant meshing driven gear,the driven gear of the first speed,and the driven gear of the main reducer are compared and analyzed.Output shaft torque response characteristics,meshing torque response characteristics of normally meshing driven wheels with or without the backlash were investigated.The results show that the gear tooth side clearance can affect the angular displacements,torque fluctuation amplitude and frequency the constant meshing driven gear,the first speed driven gear,the main reducer driven gear of the drive system,and the whole vehicle.Especially,in the first 0.5 second period of time before the starting of the automobile motor,the gear tooth side clearances have a much greater impact on the above-mentioned terms.It indicates that the change of the gear side clearance will also cause the change of the torsional vibration of the transmission system.