四轮独立驱动电动汽车单轮失效稳定性控制

Single Wheel Failure Stability Control for Four-wheel Independent Drive Electric Vehicles

为了解决四轮独立驱动电动汽车驱动系统失效时的转矩分配问题,提出了一种基于规则的驱动力控制分配策略以保证车辆在出现单轮失效情况下的稳定性和动力性。控制器采用双层控制,包括上层控制和下层控制。在上层控制中,根据驾驶员的输入与车辆状态,采用滑模控制理论计算出控制横摆角速度和质心侧偏角的附加横摆力矩。在下层控制中,根据驱动电机失效程度,考虑各约束条件,将计算出的附加横摆力矩合理地分配给各个驱动轮。利用Carsim和MATLAB/Simulink的联合仿真,选择直线、转弯以及Sine wave等工况对提出的转矩分配控制策略进行仿真分析,仿真结果表明所提控制策略能够在提高驱动系统利用率和消除前轮左右输出转矩不同对方向影响的基础上保证车辆的稳定性。

In order to solve the problem of torque distribution when the drive system of the four-wheel independent drive electric vehicle fails,this paper proposes a rule-based driving force control distribution strategy to ensure the stability and power performance of the vehicle in the case of single wheel failure.The controller adopts two-layer control,including upper layer control and lower layer control.In the upper layer control,according to the driver’s input and vehicle state,the sliding modal control theory is used to calculate the additional yaw moments for controlling the yaw rate and side slip angle.In the lower layer control,according to the degree of failure of the drive motor,the calculated additional yaw moments are reasonably distributed to each wheel in consideration of the constraint conditions.The co-simulation of Carsim and MATLAB/Simulink is used to simulate the proposed torque distribution control strategy under the conditions of straight line,turning and Sine wave conditions.The simulation results show that the proposed control strategy can ensure the stability of the vehicle on the basis of improving the utilization of the drive system and eliminating the influence of different output torques between wheels of the front axle on the direction.