智能汽车冗余电控制动系统电流传感器故障容错控制

Fault-tolerant Control of Current Sensors in Redundant Electronic Braking System for an Intelligent Vehicle

为满足智能汽车对制动系统的冗余安全要求,基于集成式电控制动系统(Integrated Electronic Braking Control System,IBC)和冗余制动单元(Redundant Brake Unit,RBU)构成的冗余电控制动系统,设计针对电流传感器故障的软件冗余和硬件冗余容错控制方法。首先,分析冗余电控制动系统工作原理,针对IBC中电流传感器故障设计冗余电控制动系统容错控制机制,并对电流传感器进行故障诊断以获得冗余电控制动系统的故障状态;然后,根据电流传感器故障诊断结果设计不同的容错控制方法,以满足容错控制机制的需求,设计基于坐标变换的软件冗余容错控制方法实现单相电流传感器故障容错控制,在对RBU的进液阀及出液阀进行增压/减压特性分析与测试后,设计RBU压力控制算法,实现多相电流传感器故障的RBU硬件冗余容错控制;最后,搭建硬件在环试验台进行硬件在环试验验证。研究结果表明:所设计的RBU压力控制算法能够实现轮缸压力控制,容错控制机制能够根据电流传感器故障诊断结果选择正确的容错控制方法,软件冗余和硬件冗余容错控制方法能在基础制动功能和主动制动功能下完成冗余电控制动系统容错控制,提高智能汽车制动系统的可靠性。

It is important to meet the redundant safety requirements of intelligent vehicles to ensure occupant safety,particularly for the braking system.Based on a redundant electronic braking system composed of an integrated electronic braking control system(IBC)and a redundant brake unit(RBU),software redundancy and hardware redundancy fault-tolerant control methods were designed for current sensor faults.Firstly,the working principle of the redundant electronic braking system was analyzed.The fault-tolerant control mechanism of the redundant electronic braking system was designed for the faults of the current sensors in the IBC,before the fault diagnosis of the current sensors was carried out to obtain the fault state of the redundant electronic braking system.Then,according to the fault diagnosis result,different fault-tolerant control methods were designed to meet the requirements of the fault-tolerant control mechanism.The software redundancy fault-tolerant control,based on coordinate transformation,was designed to realize a single-phase current sensor fault-tolerant control.After analyzing and testing the pressurization and decompression characteristics of the inlet valve and outlet valve of RBU,an RBU pressure control algorithm was designed to realize hardware redundancy fault-tolerant control of multi-phase current sensor faults based on the RBU.Finally,a test bench was built to verify the redundant electronic braking system using a hardware-in-the-loop test.The results show that the designed RBU pressure control algorithm can realize wheel cylinder pressure control,and the fault-tolerant control mechanism can select the correct fault-tolerant control method according to the fault diagnosis results of the current sensors.Moreover,the software redundancy and hardware redundancy fault-tolerant control methods can realize fault-tolerant control of the redundant electronic braking system under the basic braking function and active braking function,and thus improve the reliability of the braking system for an intelligent vehicle.