Research On Coordinated Control Of Regenerative Braking And ABS For Distributed Electric Vehicle

In order to improve the natural ecological environment on which human beings live,the emission regulations of various countries are increasingly stringent,and the governments of all countries are accelerating the development of electric vehicles.Regenerative braking technology can partially recover the mechanical energy generated by the vehicle under braking conditions and store it in the power battery.Therefore,regenerative braking function can not only improve the energy efficiency of electric vehicles,but also improve the mileage.The anti-lock function of ABS can improve the braking stability and safety of the whole vehicle.Therefore,under the condition of ensuring the braking stability and safety,the braking frequency of the motor can be increased to increase the driving range of the pure electric vehicle.Therefore,the coordinated control of regenerative braking and ABS is one of the important technologies to be solved.In this paper,the distributed pure electric vehicle is taken as the research carrier,and the whole vehicle is provided with motor braking torque by a 4-wheel hub motor.Firstly,the principle of motor braking is analyzed from a theoretical perspective,and the research status of regenerative braking energy recovery control and the coordinated control of regenerative braking and ABS by many domestic and foreign scholars is summarized.The vehicle longitudinal driving dynamics model,driver model,"Burckhardt" four-wheel tire model,motor model,double-logic threshold ABS model and so on were established by theoretical analysis method,and the relevant simulation model was established in MATLAB/Simulink software.Then,the braking force distribution theory of the front and rear axles of two-axle vehicles is analyzed,and the ECE R13 standard is combined to determine the value interval of the braking force distribution coefficient of the front and rear axles of vehicles under the condition of both no-load and full-load:.According to different braking conditions,considering power battery SOC,motor speed and other influencing factors,combined with the idea of maximum energy feedback,a braking energy feedback control strategy based on braking strength of distributed electric wheelie was developed,and the regenerative braking control method was verified by NEDC working conditions.Then,combined with the working characteristics of ABS control method based on double logic thresholds of wheel Angle deceleration and slip rate,the coordination control strategy of regenerative braking and ABS was developed under the condition of reaching the ECE R13 standard and GB/T13594-2003.Finally,according to the regenerative braking characteristics and principles of distributed pure electric vehicles,typical braking conditions and appropriate evaluation indexes are selected.On the MATLAB/Simulink operating platform,off-line simulation tests were carried out for four braking conditions,namely,medium adhesion road surface strength,medium adhesion road surface strength,emergency braking on high adhesion road surface,and medium adhesion road surface strength.The simulation results show that under the condition of ensuring the braking stability and safety,the energy recovery under the condition of medium adhesion road surface is 11.56%,the energy recovery under the condition of medium adhesion road surface is 12.76%,and the energy recovery under the condition of medium adhesion road surface is 9.27%.Therefore,the coordinated control strategy of regenerative braking and ABS formulated in this paper has a better effect of braking energy recovery under the condition of ensuring braking stability and safety.