《双机热备计算机连锁系统安全可靠性分析》-毕业论文设计（学术).doc

w w PAGE III 摘????要 铁路是大容量和大众化的交通运输工具，铁路追求的重要目标必然是安全运输；计算机联锁设备是保证铁路运输安全的关键信号设备，因而必须具有非常高的安全可靠性。如何在定性地分析和定量地计算的基础上来判断双机热备计算机联锁系统是否能满足信号系统规定的功能和安全的需求，已经成为铁路运输系统的一个重要的研究课题。 本论文立足于课题任务的研究，从双机热备计算机联锁系统在铁路实际应用中的基本组成和基本功能入手，根据影响计算机联锁系统安全可靠性的一些关键因素，利用故障树分析法建立联锁设备的故障安全模型，进行安全可靠度分析。再通过建立马儿可夫模型，进一步得出安全度和可靠度表达式，并更加详细的对其进行定性和定量分析。最后通过MATLAB仿真得出安全可靠性的曲线。通过与单机系统的安全可靠度相比较，得出双机热备计算机联锁系统的可靠度要大于单机系统，安全度小于单机系统。结果表明提高故障检测率是提高双机热备系统可靠性与安全性的重要技术措施。因此在选择故障检测覆盖率的具体数值时要综合考虑系统的性能要求，以便得到合理的数值。 关键词：双机热备计算机联锁系统；故障树分析；马尔可夫模型；故障检测覆盖率；安全可靠性 w Abstract Railway is a mass traffic facility of bulky and popular. The important target of railway wish is traffic safety certainly. Computer based interlocking equipment is key signaling facility for garanteering railway traffic safety. So its needed to be with very high safety-reliability. How to judge it whether meet certain function and safety requirements base on qualitative analysis and quantitative calculate, haven on research about work tasks become an important research task for the railway system . This paper is based on research about works task, according with the essential composing and working of dual computers based interlocking application on railway, according some key factors effect on computers based interlocking safety-reliability, establishes corresponding failure-safe model of computers based interlocking to analyze safety-reliability by methods of fault-tree . Establishing Markov model again analyses safety-reliability further with expression of safety-reliability, and the more detailed the qualitative and quantitative analysis. Finally, through MATLAB simulation getting the safety reliability curve. Through the comparison with safety-reliability of computer-based interlocking system with single computer, reaching the reliability of computer-based interlocking system with dual computers is greater than stand-alone system, but safety is smaller than stand-alone system. The results show that increasing failure checking cover ratio are