Research On The Stability Of Distributed Drive Electric Vehicle Based On The Vehicle Bus

The driving form of distributed driven EV is four motor independent drive. The four motors’ cooperative operation has high requirements on the bus’ s real-time and certainty. Because of the lack of real-time and certainty, CAN bus makes the steering control performance of the distributed driven EV poor. But the Flex Ray bus has advantages on the high transmission rate and the working mechanism on time trigger. Because of these, Flex Ray bus is more suitable for the distributed driven EV. The main research contents and results are as follows:The closed loop simulation platform of the “driver-car” is established. The simulation platform includes the eight degree of freedom vehicle model, the motor and transmission model, the wheel dynamics model, the tire model and the driver model. The simulation platform can simulate the dynamic response of the distributed driven EV very well.Control strategy adopts hierarchical control structure, takes the vehicle model of linear two degree of freedom as reference. The upper layer of the control strategy is the motion tracking layer which uses the feedforward control and the LQR feedback control to calculate the desired yaw moment. The lower layer of the control strategy is the torque distribution layer which distributes the desired yaw moment equally to the four wheels. In double lane and hunting steering test, the control strategy has a good control effect.The network control system is established to analyze the effect of CAN bus induced delay on vehicle dynamics. At the same time, the optimization solution of power bus based on Flex Ray is proposed. According to the actual demand, this paper optimizes the scheduling algorithm of Flex Ray.The software development of four node Flex Ray bus communication is made. In the GAC trumpchi AE rear motor program, the communication gateway and monitoring panel of the rear axle dual motor are developed. All of these have accumulated wheel motor develop experiences for developers. Key Words: distributed driven EV; feedforward control and LQR feedback control;...