Key Components Matching And Validation Of Single Axle Decoupling Regenerative Braking System

Regenerative braking system(RBS)is transformed the brake kinetic energy which dissipated by brake calipers and discs into electric energy stored in the battery by electric motor.Then the energy can be used again to accelerate the car.RBS is an important way to save energy and extend the driving range.To recover more kinetic energy,there is need to realize the coordinate control between the electric brake and hydraulic brake,as well as maintaining the brake feeling as usual.That is impossible for traditional brake system,which needs to study a new type of brake system.At present,some researches on that mentioned above have been carried by colleges and companies all over the world.The abroad that starts the research earlier has a solid foundation with abundant hardware resources and has already entered a production stage.The inland starts the research that mainly carried on by colleges and companies later than the abroad.Many of them are still staying at the stage of sample piece developing and have a lot of key technology matters to be solved.This thesis is based on the research content of state 863 project,and the researches carried on are as follows:(1)Based the target car structure,the form and demand of RBS has been put forward;In the matter of energy-saving potential,the layout of brake pipes has been analyzed;With the statistics of typical driving cycles and statistics data abroad,the conclusion that the intensity of the brake in most driving cycles are small has been put forward;Based on the brake legal,the potential of three brake force distribution methods has been analyzed with their hardware system supported,which decides the final decoupling form;The pressurized experiment of original ESC hydraulic regulating unit demonstrates that it can meet requirements of RBS;Based on the analysis of the original system,the system in this thesis is selected;(2)The traditional brake system model in AMESim is established by the experiment of original brake control and brake;Based on the p-V curve of front wheel cylinder,the piston,springs and gaps in the unit of brake pedal simulator are matched firstly,and then optimized by genetic algorithm;The key components of solenoid valves and check valves in the unit of brake pedal simulator are matched;(3)The control strategy mode suited for the brake system in the thesis are established.On the co-simulation perform of Matlab/Simulink and AVL-Cruise,the energy-saving effect is validated.The two indexes:rate of regenerative braking and rate of energy-saving can meet the target;on the simulation perform of Matlab/Simulink and AMESim,the current pressure of the brake system can follow the target pressure closely and the velocity is reduced steadily.At the same time,the brake feel is very comfortable.(4)The brake system is validated on the HIL test bench by the experiments of high velocity with large intensity of brake,low velocity with small intensity of brake and high velocity with variation intensity of brake.Those experiments have the same consequences with the offline simulation,which verifies feasibility of the brake system further.