Abstract: In order to improve the vehicle active safety and simplify the structure of brake system, an electro hydraulic brake (EHB) system is designed. The dynamic characteristics of EHB system is studied using theoretical and experimental method. The structure, principle and working mode of EHB system are discussed. Based on the hydraulic properties of critical components, a dynamic model of EHB system is built. Some key parameters of the model, which can’t be measured, are identified using the method of linear regression parameters identification. And the model of EHB system is validated by experiment data of a test bench. Also, the influence of some factors is investigated on the dynamic performance, including accumulator pressure, PWM signal duty ratio, wheel cylinder pressure and length of pipe. Road test is carried out using BJ2500 car equipped EHB system, and results show that the dynamic response of the developed EHB system is accurate and rapid; the vehicle can be controlled smoothly and stably during braking.

Key words: Dynamic characteristics, Electro hydraulic brake, Parameter identification, Vehicle active safety