Research Of Reliability Evaluation Method Of Subway Mian Control System

With the development of social economy and the improvement or living standard, government, society and people pay more attention to the common safety. As the vitals of city track traffic, the safe and stable operation of subway is very important. Subway main control system is the substantial guarantee of the reliable operation of subway system, so the research of the reliability evaluation method and the analysis of the reliability of subway main control system have significant academic and applied value. They're helpful to the design, maintenance and perfection of subway main control system.Based on the research of structure and function of subway main control system, its reliability level is accessed by using three common methods-reliability block diagram method, GO method and fault tree analysis method. Based on the comparison of these methods, aimed at the characteristics of subway main control system, the conclusion is given: the traditional methods aren't appropriate to evaluate the reliability of system.So dynamic fault tree analysis method is put forward to evaluate the reliability of subway main control system.On the basic of traditional fault tree analysis method, the dynamic logical gates are introduced to dynamic fault tree method. This method has characteristics such as fault tolerant, sequence dependent and redundant. The model searching method is brought forward to divide the whole fault tree into unattached static subtree and dynamic subtree. When evaluating the reliability of static subtree, it's converted into BDD to be analyzed. When evaluating the reliability of dynamic subtree, its GSPN is constructed, reachable tree is established, and then the isomorphic Markov figure is analyzed. Based on the analysis above, the results are synthesized to realize the analysis of modular dynamic fault tree, and then the reliability of system is evaluated. The station main control system is analyzed as an example. It validated that dynamic fault tree can evaluate the reliability of subway main control system.At last, the fault tree software based on Visual C++.NET is introduced. The software is used to design and analyze fault tree, it offers the computer aid to the reliability evaluation of subway main control system.