Design And Research On Electronic Anti-lock Braking System For Battery Electric Logistics Vehicle

In recent years,energy saving,emission reduction and sustainable development have become the development direction advocated by society,which has promoted the vigorous development of battery electric vehicles(BEVs).Regenerative braking can recover the kinetic energy lost during the braking process and improve the energy utilization rate.As a very important core technology of BEVs,regenerative braking has become a research hotspot.Research on electric motor braking of battery electric logistics vehicle has found that regenerative braking with electric motor as the unique braking actuator has an excellent braking energy recovery rate.However,under high braking strength conditions,the electric motor braking will cause the wheel to be locked up,which will affect the vehicle handling stability,braking safety and energy recovery efficiency.The problem of wheel lock during electric motor braking of battery electric vehicle(BEV)is analyzed theoretically.Mathematical modeling is carried out on the basis of simplified single wheel model.Due to its robustness against parameter variations and external disturbances,slip ratio and wheel deceleration are selected as control variables to design slip ratio sliding mode control law and wheel deceleration sliding mode control law.According to the different characteristics of wheel deceleration and slip ratio and certain complementarity,an electronic anti-lock braking controller is designed.The stability and robustness analysis of the electronic anti-lock braking controller are performed.The analysis results show that the electronic anti-lock braking control algorithm designed in this paper has good stability and robustness.On the basis of theoretical modeling,the electronic anti-lock braking control algorithm model was established through Matlab/Simulink.According to the vehicle parameters,the vehicle model was modeled using Truck Sim.Then,a co-simulation platform between Truck Sim and Matlab/Simulink was built.The controller key parameter ? was designed by simulations.The low and high road surfaces were selected for simulation experiments to verify effectiveness and stability of the electronic anti-lock braking control algorithm proposed in this paper.On the basis of simulation and verification,the battery electric logistics vehicle test platform was built.The designed algorithm is embedded in the vehicle control unit(VCU)as one of the main functional subsystems.In order to confirm efficiency of the proposed algorithm,vehicle tests were carried out under different road conditions,and the experiment results are also presented and discussed.According to the test results,it can be deduced that the designed algorithm can not only prevent the wheels to be locked in the course of driving and guarantee the required braking performance,but also maintain high braking energy recovery.