基于时域差异关系的车辆电子稳定性控制系统判据

A Vehicle Stability Control Criterion Based on Time Domain Disparity of Stability Variation Between Dynamic Differential Systems and Actual Vehicle

摘要:

提出一种车辆电子稳定性控制系统（electronic stability control system，ESC）补充判据用于定性判定车辆平面运动过程中可能出现的后轴滑移工况.分别研究了二自由度侧向动力学系统方程与考虑纵向加速度因素的三自由度系统方程稳定性判定方法，考虑了车轴切向力与载荷变换对轮胎侧偏特性的综合影响.通过瞬态稳定性分析方法，得到了动力学系统稳定性变化和车辆实际稳定性变化之间可以量化的时域差异关系，基于这种时域差异关系建立了稳定性超前控制方案与理论模型，以理论模型在工况切换瞬态的系统平衡点特性作为控制判据，并且对现有ESC判据应对后轴滑移工况的有效作用时间进行评价.研究表明，特定工况下横摆角速度最大值定义的约束边界与车辆实际稳定性变化边界接近，ESC系统进行控制的时间差有限，超前控制判据理论上可以更早预测车辆运动状态变化.

Abstract:

A complementary criterion for vehicle electronic stability control system (ESC) was proposed for qualitative estimation of the rear axle sliding conditions which might appear in vehicle planar motion. Taking into consideration the comprehensive effect of tangential force and axle load transfer on tire cornering characteristics, the stability criteria of 2DOF lateral dynamic differential systems and 3DOF systems with longitudinal acceleration were studied. By introducing the vehicle transient stability analysis approach, the quantized disparity between the stability variation of dynamic differential systems and that of the actual vehicle was obtained in time domain. Based on the lag effect, an anticipatory stability control solution was developed, which took the system equilibriums properties of the nonlinear reference model as the criterion. Under certain conditions which considering longitudinal dynamics, the stability boundary held by the maximum of yaw rate was close to actual stability variation of the vehicle. Thus, the response time of ESC system is limited. With the anticipatory criterion, ESC could predict vehicle status earlier.