Research And Development On The Pedal Stroke Simulator With The Function Of Active Pressurization

Along with the continuous develop of the international automobile industry.Quantity of automobiles is rising year after year in every country of the world.Environment and energy become huge obstacles hindering the continuous development of automobile industry.So now environment protection and energy conservation is becoming inexorable trend of automobile industry future development.Many domestic and overseas auto industry magnates,colleges and scientific research institutions keep trying to research on the development tendency of future automobile as well as the correlation field of technology.One of the effective ways that internationally recognized to solve energy and environment problems now is new energy automobile development.Development of Hybrid Electric Vehicle(HEV)and Electric Vehicle(EV)is the most important among new energy automobile development.Regenerative Braking System(RBS)as the core technology of HEV and EV,becomes focus of attention by insiders.Because of RBS in new energy automobiles,part of kinetic energy is converted to electric energy and stored while automobile is braking.In this way,automobile can be decelerated and recover braking energy,increase driving range,reduce fuel consumption,save energy at the same time.Research and development of RBS include control strategy research and related hardware development.Some Regenerative Braking Systems are developed now domestic and overseas.Obviously that the RBS which realize master cylinder pressure and wheel cylinder pressure decoupled works well on energy recovery.RBS with the function of active pressurization is able to realize quick response and accurate compensate while RBS needs hydraulic braking pressure.There should be a braking pedal stroke simulator in RBS.Driver braking feeling can be offered by this simulator in order to insure the safety of braking.Faw-Bestun B50 EV is the target vehicle model in this paper.Research and develop a pedal stroke simulator with the function of active pressurization on the basis of traditional braking system with ABS.The simulator has the function of braking feeling simulation and active pressurization when front axis is decoupled.The research in this paper is described below:1.Analyze the hardware used in RBS on the basis of traditional braking system.Form a new RBS configuration assembling the pedal stroke simulator described above.Formulate and analyze the control strategy of the new RBS configuration.Threshold values are calculated and each braking mode is analyzed.2.Critical components are found in the pedal stroke simulator.Matching the critical parameters of them based on requirements.Set up the model of critical components in AMEsim.Simulation with the critical parameters matched before.Check the rationality of parameters matching.3.Co-simulation on the AMEsim-Simulink simulation platform.Check the control strategy of RBS system.Once braking simulated with different initial speeds and different pedal forces and obtained pressure curves of RBS system.Result shows that the pressure of RBS system can increase and decrease reasonably according to control strategy,and meet the requirement of braking at the same time.4.Co-simulation with the driving cycles of NEDC,UDDS and J1015 on the Cruise-Simulink simulation platform.Check the ability of power recovery based on driving cycles of RBS.Result shows that the new RBS configuration has a good performance on the rate of power recovery and energy saving contribution in the co-simulation of driving cycles,and the result conforms to the technical index of new energy automobile.5.According to the new RBS configuration,set up a hardware-in-loop(HIL)test bench based on xPC Target.Check the characteristic of the components in pedal stroke simulator.Result shows that the parameters match of critical components is reasonable.In addition,once braking test of RBS is accomplished.Result shows that the braking feeling of the new RBS configuration is good.Braking requirements are reached according to control strategy.The feasibility of the hardware scheme and software scheme of this system is verified.