【摘要】 对数字化变电站自动化系统(DSAS)的可靠性进行评估是其推广的必要前提。文中提出一种包括DSAS功能可靠性和系统可靠性的评估方法,该方法同时考虑了智能电子设备(IED)的软件、硬件和通信系统的可靠性以及通信时延这几个因素。使用以IED和交换机为顶点、通信链路为边的图来表示DSAS,并根据每个元素"工作"和"失效"两个状态,得出DSAS的所有状态;使用功能完整性和时延约束判据将这些状态划分为工作状态和失效状态,并将所有失效状态合并为一个状态;使用离散时间马尔可夫链对DSAS功能和系统的可靠性进行建模,推导了状态转移矩阵的计算方法及根据状态转移矩阵和初始状态计算平均失效前时间的方法。更多还原

【Abstract】 Reliability assessment of the digital substation automation system(DSAS) is an indispensable prerequisite for its large-scale application.An assessing method including functional reliability and system reliability evaluation of DSAS is proposed.This method takes into account the reliability of software and hardware of intelligent electronic devices(IEDs),communication system reliability,and communication delays.The DSAS is presented as a graph in which the apexes stand for IEDs and switches,edges for communication links.According to the "work" and "failure" states of each element,all states of DSAS can be obtained.By means of functional integrity and delay constraints,the DSAS states can be derived and classified into two kinds,namely,"work" and "failure",and all "failure" states can be merged into one state.Then the reliability of DSAS functions and system is modeled using the discrete-time Markov chain.In addition,the method of calculating the state transition matrix and that of calculating the time prior to mean failure are derived according to the state transition matrix and initial state.更多还原