列控安全相关通信系统的安全监视

Safety Monitoring for Train Control Safety-related Communication System

本文分析了通信在列控安全关键系统执行其安全功能中的地位与作用,以及列控安全相关通信系统危险失效频率应满足的要求。探讨了安全相关通信系统的失效原理与机制。针对构建在不可信传输系统上的安全相关通信系统,讨论了安全编码和传输编码对列控系统SIL的影响。指出电磁、环境以及其他因素干扰的不确定性,是导致安全相关通信系统无法满足安全性指标的一个重要因素。提出对列控安全相关通信系统实行在线安全监视的原理和方法,给出监视周期和安全编码长度之间的定量关系,为通信安全提供有效的监视工具,以保证在环境变化或出现其他干扰因素时系统仍能达到安全要求。

The paper analyses the position and function of communication in execution of the train safety-critical system and the requirements to be satisfied with the failure frequency of train safety-related communication.The failure principles and mechanism of the safety-related communication system are discussed.In view of the safety-related communication system established on the basis of the non-trusted transmission system,the influence of safety codes and transmission codes on the train control system SIL is argued.Uncertainty of electromagnetic,environmental and other interferences is the main factor to cause the fact that the safety-related communication system cannot satisfy the safety indexes.The online safety monitoring principles and methods are illustrated,the quantitative relationship between the lengths of safety codes and monitoring cycles is given.Thus,an efficient monitoring tool is provided to ensure that the safety-related communication system remains safe while the environments are changing or other interferences occur.