Active Brake Wheel Cylinder Pressure Control Based On Integrated Electro-Hydraulic Brake System 2022-01-0293

With the development of the automobile industry, the requirements of quick response and high performance are put forward for the brake system. Since the traditional brake system cannot achieve these, the international brake parts manufacturers put forward an integrated electro-hydraulic brake system -the 1-Box. It can realize active brake through the servo motor. In addition, by controlling the pressure of the servo cylinder and working with solenoid valves, the wheel cylinder pressure can be controlled. However, it has some problems, such as hydraulic hysteresis disturbance and complex friction obstruction, which cause obstacles to the accurate control of wheel cylinder pressure. In this paper, the active braking pressure control strategy of wheel cylinders is designed based on 1-Box. First, introduce the configuration and the working principle of wheel cylinder pressure control; Next, design the servo cylinder active braking pressure control strategy composed of servo loop and pressure loop. The servo loop has completed the closed loop of the servo position control, which overcomes complicated friction configurations. The pressure loop consists of a feedforward controller and a closed-loop feedback controller to overcome the problems of hydraulic hysteresis; Then, the rate of pressure increase/reduction of inlet and outlet valves is calibrated based on the hardware-in-the-loop test bench. And a combined control strategy of wheel cylinder pressure is designed, which can realize single wheel pressure regulation and multi-wheel pressure regulation. Finally, the algorithm is tested by hardware-in-the-loop test bench. The results show that the wheel cylinder pressure control strategy designed in this paper can achieve good wheel cylinder pressure control effect of 1-Box.