IEC61508中RBD法在铁路信号冗余结构中的适用性分析  

Applicability Analysis of IEC61508 Reliability Block Diagram Method in Redundant Structures of Railway Signal System

作　　者：张宏扬 卢佩玲 张浩 ZHANG Hongyang;LU Peiling;ZHANG Hao(Communication and Signaling Research Institute,China Academy of Railway Sciences Corporation Limited,Beijing 100081,China)

机构地区：[1]中国铁道科学研究院集团有限公司通信信号研究所,北京100081

出　　处：《铁道标准设计》2022年第11期175-181,共7页Railway Standard Design

基　　金：国家自然科学基金项目-高铁联合基金(U1734211);中国铁道科学研究院集团有限公司重大课题(2020YJ133,2020YJ041);中国铁道科学研究院通信信号研究所重点课题(2020HT01)。

摘　　要：为评估IEC61508中可靠性框图(Reliability Block Diagram RBD)法推导出的危险失效概率计算公式在铁路信号冗余结构安全性分析中的适用性,以该标准主要面向的在工业过程控制领域内用于安全防护系统(A类)为对象,首先,分析其与铁路信号系统(B类)在控制结构、危险侧判定等方面的差异性,指出冗余结构故障检测的有效性及检出后的处理原则是决定系统安全性的关键因素;然后,以1oo1、1oo2和2oo2结构为例,分别采用IEC61508中的RBD法计算A类系统、马尔科夫链计算B类系统三种结构的危险失效概率;最后,以实际参数为例进行仿真计算。结果显示:用IEC61508中RBD法计算的值与用马尔科夫链计算的B类系统危险失效概率真值间存在误差,误差分别是-3.75×10^(-5),-3.77×10^(-5),3.60×10^(-5),这表明IEC61508主要适用的安全防护类系统与B类系统具有不同安全特性,若直接采用该标准中主要针对A类系统的可靠性框图法计算B类系统的安全性,则会得出偏差较大的结果。In order to assess the applicability of the dangerous failure probability calculation formula derived by the Reliability Block Diagram method of IEC61508 in the safety analysis of railway signal system redundancy structures,this paper,with reference to the safety protection system in the field of industrial process control usually aimed by IEC61508(system A),analyzes and compares the differences between system A and railway signal system(system B)in the aspects of system structure and dangerous determination,and points out that the effectiveness of redundant structure fault detection and the treatment principle after detection are the key factors to determine the system's safety.Then,by taking 1oo1,1oo2 and 2oo2 structures as examples,the paper employs Reliability Block Diagram method of IEC61508 to calculate the probability of dangerous failure of the above three structures in system A,and uses Markov Chain to calculate the probability of dangerous failure of these three structures in system B.Finally,the simulation calculation is carried out based on actual parameters.The results show that compared with the truth-value of system B calculated by the Markov Chain,errors of the probability of dangerous failure of these three structures calculated by the IEC61508 method are-3.75×10^(-5),-3.74×10^(-5),3.60×10^(-5) respectively,which indicates that there are different safety characteristics between the safety protection system usually aimed by IEC61508 and system B,If the Reliability Block Diagram method mainly for system A in this standard is directly used to calculate the safety of system B,the results may deviate greatly.

关 键 词：IEC61508 可靠性框图 安全性 危险失效 铁路信号系统 冗余结构 

分 类 号：U284[交通运输工程—交通信息工程及控制]