基于分层控制的汽车电液复合制动稳定性控制研究

Stability control of vehicle electro-hydraulic composite braking system based on hierarchical control

汽车在复杂工况下紧急制动时容易发生侧滑、甩尾等问题。为提高汽车制动稳定性,设计了一种电液复合制动稳定性控制系统。该系统采用分层控制结构,上层运动控制器根据车辆的运动参数和驾驶员意图计算车辆期望状态,下层控制分配器根据协同控制决策模块实现制动压力及横摆力矩的分配,对车辆进行制动稳定性调节。同时,利用Simulink与Carsim联合仿真平台进行仿真实验。结果表明:所提出的分层控制策略在保证车辆制动效能的基础上,能有效地改善车辆制动时的方向稳定性,控制精度高,鲁棒性好。

Undercomplex working conditions,the vehicle may suffer from sideslip and tail flick problems during an emergency braking.In order to improve the stability of vehicle during emergency braking,an electro-hydraulic composite braking stability control system is proposed.To this end,thehierarchical controlstructure is adopted in this paper.In detail,the upper-loop motion controller gives out the expected state of the vehicle according to the motion parameters and the driver’s intention.And the lower-loop is used to allocatethe braking pressure and the yaw moment with respect to the collaborative control decision-making module.In this way,the stability of the braking vehicle can be properly adjusted.Finally,joint simulation is carried out by Simulink and CarSim.Simulation results demonstrate that,the proposed hierarchical control strategy can guaranteethebraking efficiency,and also improve the directional stability,control accuracy and robustness of the vehicle.