| The key of decide Vehicle active safty is the braking system. In recent years, Because of advances in vehicle technology and Improve the speed as well as Driver's non-professional, the importance of braking system is becoming more and more obvious. The potential of conventional braking system improve the braking performance is limited because of the structure and the principle is limited, It must be replaced by a new braking system, That is, Brake-by-Wire system. The future direction of development is Brake-by-Wire system , It contributes to the braking system integrated, Such as ABS, TCS, ESP and Electronic Parking Control System can be easily integrated. Brake-by-Wire system in accordance with the implementing agencies and the different levels of technological development can be roughly divided into two categories: EHB(Electronic Hydraulic Braking System)and EMB(Electronic Mechanical Braking System).EMB is the future direction of development of automotive braking systems, EHB is the first step towards this goal. EHB system can be described as transition Product ranging from traditional brake systems to EMB, EHB System retains the original of a hydraulic braking system, reliability is assured;It Still uses the 12V vehicle power supply, Existing electrical systems can meet the power supply. Therefore, EHB system has broad prospects for development by virtue of its high reliability and lower hardware requirements.For the superiority of EHB system as well as domestic less reseach on EHB system ,The dessertation carried out many research work On the EHB system from product development to EHB hydraulic modulator modeling and simulation analysis and vehicle stability control algorithm based on EHB system.In chapter one, Focuses on the reseach meaning of EHB system as one of the Brake-by-Wire system, research at home and abroad of EHB System, and introduce the structure and working principle of EHB system which is developmented independently.Chapter two is the EHB hydraulic modulator modeling and simulation analysis bsed on AMESim software. This chapter first analysis EHB hydraulic modulator essential components of high-speed switching solenoid valve static characteristic and dynamic characteristic, Through in-depth study of high-speed switching solenoid valve features, In order to be able to better research EHB hydraulic modulator performance; Second is the EHB system hydraulic modulator main hydraulic components as well as set up the mathematical model and the AMESim model, By analysis of simulation results of EHB hydraulic system dynamic characteristics in AMESim to make sure that the hydraulic modulator model set up is correct; Finally is analysis of the main parameters of essential hydraulic components which has an important impact on the EHB hydraulic system dynamic characteristics batch run simulation in AMESim software. Study the various parameters impact on the overall performance of the EHB hydraulic system, Thus ,it unnecessary over-reliance on the experience of designer to get a better parameters matching of the hydraulic components which set up of EHB hydraulic modulator system.Chapter three is research on the Vehicle stability control algorithm for EHB System. In this chapter, analysis of the reasons which cause instability of vehicle and ways to improve vehicle stability and variables selected for vehicle stability control were discussed in details, according to two degrees of freedom vehicle model derive the reference Yaw rate and the side slip angle, the previous fixed threshold is no longer used for instability threshold of the vehicle which is determined by vehicle sports-related status variables, Target yaw moment of the control algorithm using robust fuzzy control algorithm,which is calculated by three control algorithms of yaw rate,side slip angle and yaw rate and side slip angle united as the control variable respectively. According to the tire friction circle theory derived the strategy of single-wheel brake force distribution,and analysis the calculation of target brake pressure. Through the study of this chapter set up a more comprehensive vehicle stability control theory.Chapter four is research on united simulation of vehicle stability control based on EHB system. In this chapter, Simulation and Verification of a set of vehicle stability control algorithm which is set up in the previous chapter. Simulation environment used is no longer a single MATLAB/Simulink software, but exert the respective strengths of AMESim in hydraulic modeling, CarSim in vehicle dynamics modeling and MATLAB/Simulink in the control system modeling. Using the united simulation environment of the three software to simulation and verification of a set of vehicle stability control algorithm which is set up in the chapter is correction. In the simulation process, open-loop simulation of Single-Cycle Sinusoidal and the closed-loop simulation of Double Lane Change is taken separately for the three control algorithms. Through analysis of the simulation results to verificate the correctness of the vehicle stability control algorithm.Chapter five is the summary and prospects of the dessertation. Summary of the dessertation research results and innovation achieved, and make the objective prediction and comments of the dessertation application of theoretical and practical value. Explanation of the problem existed on the course of the study and envisagment of the future of the EHB system.
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