Research On Brake Stability Compensation Control Of Distributed Drive Electric Vehicle With Brake Failure

With the development of automobile industry,the distributed drive electric vehicle with Braking-by-Wire has become the trend of vehicle configuration.The braking system of the vehicle with this configuration is composed of highly electrified electro-mechanical braking system and hub motor regenerative braking system,so the possibility of braking failure is pretty high.At the same time,the vehicle with this configuration has good fault tolerance potential in braking.Therefore,it is of great significance to study the stability compensation control of the brake actuator failure of the distributed drive electric vehicle with line control.This thesis mainly does the following research:(1)According to the configuration of distributed electric vehicle braking system,the electro-mechanical braking system model,wheel motor regenerative braking system model,vehicle dynamics model and tire model are established to analyze the executive performance of the electro-mechanical braking system,so as to ensure that the built model can be used for simulation verification.(2)The vehicle dynamics model of single wheel braking failure is established,and the influence of different braking failure on vehicle stability is analyzed.Through the co-simulation of MATLAB/Simulink and Car Sim,the yaw angle,deviation distance and braking distance are selected as the parameters to characterize vehicle braking performance,and the influence of single wheel braking failure on vehicle braking performance under different working conditions is analyzed.(3)According to the different types of brake under different braking strength,a control strategy with yaw rate and sideslip angle as control parameters is proposed to control the stability of braking direction.Based on the law of axle load transfer,a torque reconfiguration controller is established to deal with the brake actuator failure under light and moderate braking conditions.Based on the high gain feedback robust control theory,the front wheel angle controller is designed under the condition of heavy braking failure.Under heavy braking condition,the front wheel angle controller,torque reconfiguration controller and ABS controller work together to control the vehicle braking stability.(4)The control strategy model of MATLAB/Simulink is established.Complete the co-simulation verification of Car Sim and MATLAB/Simulink.The hardware in the loop platform is built based on x PC Target technology to verify the code feasibility and real-time performance of the control strategy.