Research On Fault - Tolerant Control Method Of Mechanical Electronic Parking Braking System

EPB (Electronic Parking Brake) system is a major innovation compared to conventional parking brake system, which removes excess handbrake lever and other mechanical components, saving driving space, with the integration of smart parking brake and hill-start assist functions in one, improving the comfort and reliability of driving, but the electronic system has its own hidden safety problems, therefore it need fault-tolerant control.In this paper, the failure based on the mathematical model of the sensor, controller and actuator in mechanical electronic parking brake system was analyzed, and the implementation of the EPB system with fault-tolerant control was designed. According to the mathematical model and the estimation algorithm in each system module, the simulation of EPB with fault-tolerant control was built through the Matlab/simulink software and the PID controller, simulating this case that the system can achieve EPB function when sensor is failed.The hardware in the loop simulation platform was built with the dSPACE AutoBox as a system control unit to verify whether the fault-tolerant control system can meet the functional requirements in the real environment. The system control strategy was designed according to the function requirements of EPB system, and the corresponding control program was written in Matlab/simulink software. The PCB of driving circuit was drawn with the Altium Designer software, and the hardware circuit board was soldered according to that, then the drive circuit board, AutoBox and notebook was connected to each port to form a closed-loop control.Finally, the feasibility of this fault-tolerant control system designed by this paper was verified by analyzing the bench test data.