Study On Coordinated Control Of ABS And Regenerative Braking For Hybrid Electric Vehicle

With the intensification of oil crisis and environmental pollution,governments have set stricter emission standards for automobiles.Under this background,all major OEMs and Tier 1 suppliers in the world regard new energy vehicles as the current research hotspot.In particular,the hybrid vehicle as a transitional vehicle from a conventional fuel vehicle to a pure electric vehicle can balance good power and effectively reduce emission which is the new energy vehicle with the highest market share.At the same tine,regenerative braking has been widely used as a key technology to improve the fuel economy of new energy vehicles;however,how to ensure safety during braking while simultaneously recovering energy is still unclear,particularly during the time that a car activates the ABS.Researchers to date have mostly focused on how to coordinate the distribution of the motor braking torque and hydraulic braking torque?Aiming at this problem,the control strategy of pure motor ABS braking is proposed,and three strategies of coordinated distribution of motor braking force and hydraulic braking force when triggering ABS are proposed.The feasibility of the strategies are verified by simulation.The main work of this paper is as follows:(1)The transmission system scheme of plug-in four-drive hybrid electric vehicle is designed.According to the characteristics of regenerative braking system and anti-lock braking system,the hardware structure scheme and software structure scheme of the composite braking system are formulated.(2)Two kinds of pure motor ABS braking schemes are proposed by analyzing the constraints in the process of pure motor ABS braking,including fuzzy PID control and double logic threshold control.(3)Three strategies for coordinated control of motor braking force and hydraulic braking force after triggering ABS are formulated.(4)The simulation models of motor,braking system,tire,battery and vehicle are built,and the response characteristics of motor and hydraulic system are simulated and analyzed.At the same time,the coordinated control strategy of ABS and regenerative braking system is compiled based on Stateflow.Finally,the forward simulation model is obtained.(5)The simulation analysis of regenerative braking strategy,pure motor ABS braking strategy and three coordinated control strategies of regenerative braking and ABS are carried out,and the simulation results are compared and analyzed.Through the research on coordinated control of regenerative braking and anti-lock braking system,the feasibility of using pure motor ABS braking under low braking intensity is verified.At the same time,the three coordinated control strategies of regenerative braking and anti-lock braking system proposed in this paper are verified.The applicability of the three strategies is explained,which can provide reference for further study of ESP system.