整体式EHB系统建模及安全机制研究OA北大核心CSTPCD

To address the random failure of electrical and electronic systems in EHB systems,this paper proposes a safety mechanism based on fault diagnosis and fault tolerance strategy.A braking system model consisting of electronic control unit (ECU),pedal feeling simulator unit,pressure building unit and hydraulic control unit is built in AMEsim.Our simulation analysis shows the model achieves fast response and high precision,meets the requirements of the braking system and provides a good pedal feeling curve.With the failure of pedal displacement sensor as an example,the safety mechanism of integrated EHB system is designed.Based on the model,redundant simulation signals of the pedal displacement sensor are obtained.Fault diagnosis and fault tolerance strategies for pedal displacement sensor failure are designed,and the failure simulation tests of the pedal displacement sensor are conducted under typical working conditions.Our results show the fault diagnosis of the pedal displacement sensor is realized and the correct pedal displacement signal is generated through fault tolerance with fast diagnosis,demanstrating effective improvement in the functional safety of integrated EHB system.