横摆力矩滑模控制的轮边驱动电动汽车稳定性分析
Stability Analysis of Wheel-drive Electric Vehicle Based on Sliding Mode Control of Yawing Moment

为了提高轮边驱动电动汽车行驶的稳定性，提出横摆力矩滑模控制的稳定性控制策略，采用层次化结构的稳定性控制器。针对极限工况下车辆的状态估计误差偏大，基于无迹卡尔曼滤波（UKF）理论设计了适用于轮边驱动电动汽车的状态估计方法，根据UKF估计的车辆状态计算，设计滑模运动控制器计算所需的横摆力矩。考虑到转矩分配时的实际约束条件，设计了控制分配器，采用二次规划方法优化分配各轮上的驱动/制动扭矩。仿真结果表明：该稳定性控制器能够快速施加驱动力或制动力，及时、准确地控制车辆的横摆角速度和质心侧偏角，提高车辆的操纵稳定性。
The stability control strategy with hierarchical structure based on sliding mode control of yawing moment is developed to improve the stability control for wheel drive electric vehicle. For the case of excessive status estimation error of the vehicle at limiting conditions, a status estimation method which is appropriate for wheel drive electric cars is designed based on the unscented kalman filter(UKF) theory. According to the vehicle status calculation estimated by UKF, the yawing moment for calculation of motion controller is designed. Allocation controller is designed when considering the practical constraints of torque distribution, and quadratic programming method is adopted to optimize the distribution of the driving/braking torque on each wheel. The simulation results show that the driving/braking force can be applied rapidly, and the yaw rate and the sideslip angle are also controlled accurately and timely using the stability controller. The vehicle driving stability is improved effectively