具有多项式时间复杂性的离散事件系统安全诊断

摘要

Fault diagnosis of discrete event systems (DESs) is to detect the unobservable fault events occurring in systems within a finite delay, but the safety of the involved systems during the detection delay is always neglected. In order to solve this problem, this paper aims to propose an approach for safe diagnosability of DESs with a polynomial-time complexity. Firstly, the notion of safe diagnosability of DESs is formalized. Then the recognizer of illegal language is constructed to identify the sequences of the forbidden operations. Based on the recognizer, the safe verifier is constructed to perform the safe diagnosis for a given system. Furthermore, a necessary and sufficient condition of safe diagnosability of DESs is presented. It is worth noting that the safe diagnosability of DESs can be realized with a polynomial complexity by analyzing the complexity of constructing the verifier and the complexity of checking of the safe diagnosability of DESs.%离散事件系统的故障诊断能将已发生的不可观故障事件及时诊断出来,但往往容易忽略故障诊断期间系统的安全性.为解决这一问题,提出了一种具有多项式时间复杂性的安全故障诊断方法.先对离散事件系统的安全可诊断性进行了形式化,再通过构造一个非法语言识别器对系统被禁止操作序列进行识别,并在此基础上构建了一个对系统实施安全诊断的安全验证器,得到了一个关于离散事件系统安全可诊断性的充分必要条件,实现了对系统的安全故障诊断.同时,通过对安全验证器的构建与安全可诊断性的判定的复杂性分析,得到了该安全故障诊断方法可在多项式时间内实现等结论.