燃料电池轿车动力传动系统非线性动态特性仿真分析

Numerical Investigation into Nonlinear Dynamical Characteristics of Fuel Cell Vehicle Powertrain System

某燃料电池轿车在加速起动与回馈制动时会发生明显的纵向冲击抖振现象。针对这一问题,建立包含电动机、电动机轴、减速器/差速器总成、左右半轴、左右车轮/车身七个子模块,考虑减速器齿轮齿侧间隙与啮合刚度特性以及轮胎-地面摩擦特性的非线性动力传动系统动态模型。运用Matlab/Simulink软件对起步加速与回馈制动工况下的整车与动力传动系统的动态响应进行了仿真预测。仿真结果表明,燃料电池轿车动力传动系统会在电动机工作转矩发生突变时产生动力传动系统的扭转振动现象和整车的纵向抖振现象,齿侧间隙会引起齿轮的拍击现象并加剧动力传动系统的动载荷。研究成果能够合理解释燃料电池轿车纵向抖振的机理,可以为燃料电池轿车等电动汽车的动力传动系统的动态匹配设计提供理论方法。

Significant longitudinal vibration is found when a China-made fuel cell passenger car accelerates and brakes. To explain this phenomenon, a nonlinear dynamical model of fuel cell vehicle powertrain system is established considering the gear backlash and tire-road friction characteristics, which includes electric motor, motor shaft, gear box and differential assembly, left and right axle shafts, tire and car body, total seven sub-models. Based on this model, the dynamical characteristics of vehicle acceleration and generative braking are simulated by using Matlab/Simulink software. The numerical results show that the fuel cell vehicle will occur longitudinal vibration and impact with powertrain system torsional vibration if there is sudden electric motor torque variation when the vehicle is being accelerated or braked, and the gear backlash can cause gear impact and increase dynamical torque load. The research can explain the mechanism of fuel cell vehicle powertrain system oscillation and longitudinal vibration, and can be helpful for dynamic analysis and design of electric vehicle powertrain system.