基于电流动态特性的EGR阀故障诊断方法及系统

Fault Diagnosis Method and System of EGR Valve Based on Current Dynamic Characteristics

EGR(Exhaust Gas Re-circulation,EGR)阀作为汽车废弃循环系统的关键部件,具备控制精度高、响应速度快以及出色的稳定性等优点。但因其恶劣的工作环境,长期的工作会导致其极易发生故障,这对其可靠性的设计要求提出了很高的要求。本文针对有限转角力矩电机式的EGR阀工作原理,建立对应的数学模型,并在Matlab/Simulink上搭建相应的仿真平台,通过对其电流特征进行分析,验证模型可靠性。基于仿真结果,设计了一套以STM32微处理器为核心的控制系统,驱动EGR阀的正常运转并进行位移与电流信息采集。根据采样的EGR阀的电流信号特征,将实验数据与理论数据的对比,提出了可靠的特征参数,验证了该诊断方法的可靠性与系统设计的准确性。

EGR(Exhaust Gas Re circulation,EGR) valve,as a key component of the vehicle waste recycling system,has the advantages of high control accuracy,fast response and excellent stability.But because of its bad working environment,long-term work will lead to its failure easily,which puts forward high requirements for its reliability design.In this paper,the corresponding mathematical model was established according to the working principle of the EGR valve with limited angle torque motor,and the corresponding simulation platform was built on Matlab/Simulink.Through the analysis of its current characteristics,the reliability of the model was verified.Based on the simulation results,a control system with STM32 microprocessor as the core was designed to drive the EGR valve to operate normally and collect the displacement and current information.According to the current signal characteristics of the sampled EGR valve,the reliable characteristic parameters were proposed by comparing the experimental data with the theoretical data,which verified the reliability of the diagnosis method and the accuracy of the system design.