A new generation algorithm of fault tree minimal cut sets and its application in CBTC system

Fault Tree Analysis (FTA) is a classic method in reliability and safety engineering. With the increase of system scale and complexity, the amount of work is heavily loaded. Thus the computer aided FTA method is important for related analysis. Existing computer aided FTA analysis methods invariably confront combinatorial problems which are computationally expensive and often with exponential increase of complexity, especially when it comes to large scale fault trees. In this paper, we propose a method based on the Binary Decision Diagram (BDD) with new conversion rules which are derived from the Component Connection Method. Besides, the Depth First Search (DFS) is applied to generate MCSs (Minimal Cut Sets). In the end, the Zone Controller of the CBTC (Communication Based Train Control) system is analyzed in case study. The result proves that the application of our new algorithm, of linear complexity, is more efficient than the algorithm of verifying all possible basic event combinations, both in computation speed and memory usage.