AFS/DYC协调控制的分布式驱动电动汽车稳定性控制

为进一步提高分布式驱动电动汽车行驶过程中的稳定性,提出主动前轮转向(AFS)和直接横摆力矩控制(DYC)协调控制策略.为提高车辆稳态行驶时转向能力,设计基于滑模控制(SMC)的前轮主动转向控制器实时修正前轮转角;以维持车辆工作在稳态工作区为控制目标,设计基于模型预测控制(MPC)的车辆稳定性控制器,通过设定的分配规则按轴荷比等比例分配各轮驱/制动力矩.利用相平面法作为判定依据自适应分配各控制器权重,实现控制器之间的切换.在连续转向工况下,对控制算法进行仿真验证.结果表明:在相同转角输入下,相较于无控车辆,受控状态下车辆的横摆稳定性能提高了16%,行驶状态得到了改善.

Stability Control of Distributed Drive Electric Vehicle Based on AFS/DYC Coordinated Control

To improve the stability of the distributed drive electric vehicle during driving, a coordinated control strategy of active front steering(AFS)and direct yaw moment control(DYC)was proposed. In order to improve the steering ability of the vehicle during steady-state driving,a front-wheel active steering controller based on sliding mode control(SMC)was designed to correct the front-wheel angle in real time. As the control goal of keeping the vehicle working in the steady-state area, a vehicle stability controller based on model predictive control(MPC)was designed, and the wheel drive/braking torque was distributed in equal proportions according to the axle load ratio through the set distribution rules. The phase plane method was used as the decision basis for the weight adaptive assignment of each controller to realize the switching between the controllers. Under continuous steering conditions, the control algorithm was simulated and verified. The results show that: under the same input angle, the yaw stability of the vehicle under the controlled state is increased by 16%, and the driving state is improved compared with the uncontrolled vehicle.