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The Electronic Stability Program (ESP), as a key actuator of traditional automobile braking system, plays an important role in the development of intelligent vehicles by accurately controlling the pressure of wheels. However, the ESP is a highly nonlinear controlled object due to the changing of the working temperature, humidity, and hydraulic load. In this paper, an accurate pressure control strategy of single wheel during active braking of ESP is proposed, which doesn’t rely on the specific parameters of the hydraulic system and ESP. First, the structure and working principle of ESP have been introduced. Then, we discuss the possibility of Pulse Width Modulation (PWM) control based on the mathematical model of the high-speed switching valve. Subsequently, the pressure building characteristics of the inlet and outlet valves are analyzed by the hardware in the Loop (HiL) experimental platform.

With the development of modern vehicle chassis control systems, such as Anti-Lock Brake System (ABS), Acceleration Slip Regulation (ASR), Electronic Stability Control (ESC), and Regenerative Braking System (RBS) for EVs, etc., there comes a new requirement for the vehicle brake system that is the precise control of the wheel brake pressure. The Electro-Hydraulic Brake system (EHB), which owns an ability to adjust four wheels’ brake pressure independently, can be a good match with these systems. However, the traditional control logic of EHB is based on the PWM (Pulse-Width Modulation), which has a low control accuracy of linear electromagnetic valves. Therefore, this paper presents a research of the linear electro-magnetic valve characteristic analysis, and proposes a precise pressure control algorithm of the EHB system with a feed forward and a PID control of linear electro-magnetic valves.