Research On Electro-Hydraulic Hybrid Braking System Of Test Vehicle With Four Hub Motor Actuated

With the increasingly severe environmental issues and the deployment of energy security strategies,the vehicle industry is undergoing reform and development in recent years,and energy conservation emission reduction and improvement of energy utilization are hot issues that all enterprises have to face.In the vehicle’s braking system,the electric and hydraulic compound braking system includes electric mechanism power and hydraulic braking force.Under the premise of ensuring braking safety,it can also recover part of the braking energy through the motor regenerative braking force to extend the cruising range.Moreover,the braking force of each wheel can be adjusted individually,which has great advantages in dynamic control and other aspects.In this paper,on the basis of the experimental vehicle driven by the in-wheel motor in the laboratory,the research on the electric and hydraulic compound brake system is carried out.By analyzing the relevant principles of regenerative braking system energy recovery and the structure of composite braking system,the overall scheme design of composite braking system is determined.Based on the ideal braking force distribution strategy,the control strategy design to composite braking system is completed,The vehicle system model and the control strategy model were established in AMEsim and Matlab/Simulink respectively,and the simulation verification of two braking conditions was carried out.The results show that under this control strategy,the coordination of electric and hydraulic braking forces is better,with energy recovery.The hydraulic brake system was restructured on the test vehicle,the hydraulic brake force adjustment function components were selected and installed,and the brake oil circuit was redesigned,Based on a development board,design the controller of the hydraulic brake force adjustment unit and For the drive circuit.Based on this,relevant tests were carried out,including the pressure characteristic test of the high-pressure accumulator,the pressure follow ability test of the wheel cylinder,and the compound brake test of the vehicle.The test results show that the designed hydraulic braking force adjustment unit has fast pressure build-up response and good pressure follow ability,which meets the pressure requirements of the system,and the coordination between the electric and hydraulic braking systems is good during the vehicle braking process.The braking energy recovery can be realized,and the design goal is reached.