基于通信对象状态判断的二乘二取二安全计算机平台主备切换研究

Research on Active-standby Switch of Double 2-vote-2 Safety Computer Platform Based on Status Judgment of Communication Object

铁路信号控制系统通常采用专用的二乘二取二安全计算机平台用于信息传输、逻辑运算及对象控制等功能。随着外部通信对象的种类与数量日益增多,现有的安全计算机平台主备切换方法可能存在故障发生时不切换或同一外部故障发生不必要切换等问题。提出一种基于通信对象的通信状态判断的二乘二取二安全计算机平台的主备切换方法。该方法首先定义倒机值和优先级等量化指标,设计倒机值计算公式;然后从建立通信、判断通信中断和计算通信正常个数等方面,分析主用系和备用系不同的判定依据;最后比较倒机值大小,决定是否进行主备切换,并在典型场景中对该方法进行实际应用验证。结果表明:基于通信对象状态判断的主备切换方法相较于板卡级和计算通信数量的主备切换方法,提高了系统的可用性,减少了非必要倒机等影响系统安全性的现象;所设计主备切换方法通过对不同通信方式、不同冗余结构和不同控制设备分类分析,可提高系统的可靠性和安全性。

The railway signal control system usually adopts a special double 2-vote-2 safety computer platform for information transmission,logic operation,object control and other functions.With the increasing varieties and numbers of external communication objects,the existing active-standby switch methods for security computer platforms may have problems such as not switching when a failure occurs or unnecessary switching when the same external failure occurs.This paper presents an active-standby switch method of double 2-vote-2 safety computer platform based on communication state judgment of communication objects.This method first defines the quantitative indicators such as switching value and priority,and designs the calculation formula of switching value.Then,from the aspects of establishing communication,judging communication interruption,and calculating the number of normal communication,the method formulates different judgment criteria for the active and the standby system.Finally,the method compares the switching values,and decides whether to switch between the active and the standby system.The method is verified in practical applications in typical scenarios.The results show that the active-standby switch method based on the communication object state judgment improves the system availability and reduces the unnecessary switching phenomena that affect the system security compared with the active-standby switch method based on the board level and the number of calculations;the designed active-standby switch method can improve the reliability and security of the system by classifying and analyzing different communication modes,different redundant structures and different control devices.