Study On Coordinated Control Of ABS And Regenerative Braking For Electric Vehicle With Four-wheel Independent Drive In-wheel Motors

Four wheel In-wheel Motors torque of the four-wheel independent drive electric vehicle can be controlled independently, so the vehicle has unique advantages in active safety and energy saving control. ABS control strategy of four wheel independent drive in wheel motor electric vehicle, regenerative braking control strategy, ABS and regenerative braking coordinated control strategy are investigated in this paper based on the National Natural Science Foundation of youth fund project 51305190 and enterprise four wheel independent electric drive model car technology development project. Through the rational allocation of the four round of the regenerative braking torque, the full recovery of braking energy can be achieved in the premise of ensuring braking efficiency and stability.The content of this paper mainly includes the following several aspects:(1) The model of four wheel drive In-wheel Motors electric vehicle was established. The software of Matlab/Simulink was used to build the suspension system model, tire model, driver model, model of the motor and battery model, and the co-simulation of the vehicle dynamics simulation software CarSim to built four wheel independent drive wheel hub motor for electric vehicle model.(2) Study on the control strategy of ABS. The two control strategy of ABS are designed: with slip rate of wheel and the rate of slip rate as the control target of the ABS fuzzy control strategy; with slip rate of wheel and the wheel angle add/subtract speed of target control of ABS logic threshold value control strategy, select high adhesion road, low adhesion road, on the open road and linking road, on the design of the ABS logic threshold value control strategy for high-speed of emergency braking simulation test, validate the model effectiveness.(3) Study on the control strategy of regenerative braking. With the braking strength as the control target of the four wheel independent drive In-wheel Motors electric vehicle regenerative braking control strategy is designed, in the light of the small and medium-sized braking strength condition, select several typical driving cycles and three different braking intensity condition, simulation tests were carried out on the design of regenerative braking control strategy and model verification.(4) Study on coordinated control strategy and regenerative braking ABS. Based on the study of ABS control strategy and regenerative braking control strategy, with the brake pedal open degree and speed of the target control of ABS and regenerative braking control strategy is designed, in the light of the large braking strength conditions, selects the high adhesion road, low adhesion road, on the open road and linking road of the ABS and regenerative braking coordination control strategy for the rapid emergency braking simulation test and validation of the model.(5) Driving simulator hardware in the loop test verification. Based on the above research, selected a small brake strength condition, on the design of regenerative braking control strategy hardware in the loop test; select high adhesion road, low adhesion road and on the open road, on the design of ABS and regenerative braking coordinated control strategy of hardware in the loop test and verification of the model effectiveness.Experimental results show that the designed ABS control strategy in high dangerous condition has better braking efficiency and stability; braking energy can be fully recycled by regenerative braking control strategy in the primary and secondary braking intensity; coordination of ABS and regenerative braking control strategy not only ensures the vehicle braking stability, but also fully recycles the braking energy to accomplish the utilization of renewable energy under the high-speed emergency braking.