含间隙电驱动行星变速系统瞬态工况纵向振动抑制研究

Owing to the high response speed of driving motor, the change of load of powertrain system leads to longitudinal vibration of electric vehicle. The anti-jerk control becomes a hot research topic due to fast response and flexible control of driving motor. It’s similar to conventional diesel vehicles that the effects of the powertrain backlash and the flexibility on the longitudinal vibration performances, which influence the ride comfort directly. The dynamic model of powertrain system with the gear backlash and the flexibility has built based on the piecewise affine characteristics of the backlash nonlinearity. The influence of the coupling action between the gear backlash and the flexibility for torque dynamic control of powertrain system has been developed. The influence mechanism of nonlinearities mentioned above affecting on torque response of powertrain system is identified. The simultaneous state observer has been established to estimate the torque of output shaft and the position of gear backlash. The active compensating objective function is explicated based on the observer under Tip-in and Tip-out conditions, and the model predictive control is used to following the objective function for improving the ride comfort. Considering the hybrid system characteristics for gear shifting with gear backlash, the hybrid predictive control has been applied on gear shifting for anti-jerk control. The equivalent explicit expression of the system with model predictive control law is completed based on multi parametric programming technology for hardware implementation. Moreover, the control law was implemented in a rapid control prototype, which builds the experimental and theoretical basis for anti-jerk control in transient condition of electric powertrain system.

电动汽车的驱动电机具有灵敏的响应特性，转矩突变对电驱动变速系统冲击较大，如何通过控制电机转矩抑制传动系统纵向振动的问题引起广泛关注。与传统内燃机车辆类似，传动轴的弹性变形及齿轮啮合间隙等因素影响了电动汽车的动态性能，导致车辆驾驶舒适性明显下降。本项目基于齿轮间隙呈现的分段仿射非线性特征，建立耦合轴系柔性及齿轮间隙的电驱动变速非线性系统动力学模型。阐明轴系弹性变形与齿隙非线性环节耦合作用对电驱动变速系统扭矩控制的动态影响规律。针对非线性环节确定急加速急减速条件下的主动补偿控制目标，利用混杂系统理论对传动轴扭矩与齿隙位置进行状态估计，根据混杂状态观测信息采用模型预测算法进行主动补偿控制。明晰含间隙换挡过程混杂动态特征，完成考虑齿轮间隙的换挡过程混杂模型预测控制器设计。利用多参数规划实现系统模型预测控制律的显式表达并进行硬件实现，为电驱动变速系统瞬态工况纵向振动抑制提供试验和理论基础。

电动汽车的驱动电机具有灵敏的响应特性，转矩突变对电驱动变速系统冲击较大，如何通过控制电机转矩抑制传动系统纵向振动的问题引起广泛关注。传动轴的弹性变形及齿轮啮合间隙等因素影响了电动汽车的动态性能，导致车辆驾驶舒适性明显下降。本项目基于电驱动系统非线性特征，对变速器工作状态进行受力分析，结合拉格朗日动力学方程和虚功原理建立耦合轴系柔性及齿轮间隙的电驱动变速非线性系统动力学模型。设计状态观测器对换挡过程的变速器及传动轴的状态参数进行在线估计，基于状态估计信息设计H∞鲁棒控制器，对换挡过程中的电机转速进行跟踪控制仿真，对比验证该控制器在不存在/存在外界干扰情况下的控制效果。基于Radau伪谱法对该问题进行转化与求解，利用插值多项式对换挡过程中系统的状态变量和控制变量进行逼近，将换挡过程的最优控制问题转换为非线性规划问题，完成考虑齿轮间隙的换挡过程换挡执行机构最优控制器设计。搭建电驱动变速系统换挡试验台架，利用多参数规划实现系统最优控制律进行硬件实现，换挡品质得到有效的改善，为电驱动变速系统瞬态工况纵向振动抑制提供试验和理论基础。