| Sideslip angle and yaw rate are important parameters to evaluate vehicle safety and handling stability.In order to improve the safety of new energy vehicles,this paper proposes a coordinated control system based on dual-motor rear-drive electronic differential system and active steering control system to improve the lateral stability of Dual-Motor rear-drive vehicles and further enhance their safety.In the algorithm design stage,2-DOF and 7-DOFvehicle models are deduced based on Newton’s second law;magic formula tire model is established to obtain accurate tire force output in 7-DOF vehicle model;in order to reduce human intervention,according to Ackermann steering geometry,a single-point preview driver model and a standard double-lane-shifting road model are established to obtain ideal steering angle.On this basis,a cooperative lateral stability control system based on dual motor rear drive electronic differential system and active steering system is designed.In the design of Dual-Motor rear-drive electronic differential system,a second-order sliding mode controller based on sliding mode centroid sideslip angle observer,Lyapunov theory,sliding mode control theory and moment allocation strategy is proposed to solve the problem of Dual-Motor rear-drive motor torque control.In the active steering control system,an active steering control strategy based on path preservation is proposed.The sliding mode control algorithm is designed,and the particle swarm optimization(PSO)algorithm is used to control the two systems.In the validation stage,the control system is simulated by Simulink and Carsim.The results show that: 1)Cooperative control algorithm inherits the advantages of active steering system and has high accuracy in path planning.2)Collaborative control algorithm inherits the advantages of second-order sliding mode dual-motor electronic differential system,and has the advantages of small amplitude and low chattering.3)Under the condition of 100 km/h double lane change,the cooperative control algorithm can improve the lateral stability of vehicles by 60%.4)Compared with GG and phase diagrams,the result area of cooperative control algorithm is smaller and the driving is more stable.Finally,the hardware-in-the-loop platform is built with PXI equipment,LabVIEW and Carsim RT.The hardware-in-the-loop verification of the designed control system is carried out to improve the reliability of the control system. |
