Fuzzy multi-state fault tree analysis based on fuzzy expert system

With the development of large-scale, intelligent and complex systems, the conventional fault tree analysis method is incapable of analyzing the fault tree model of systems with vague data and multi-state. As a solution, this paper proposes a new approach of fuzzy multi-state fault tree analysis method based on a fuzzy expert system. Fuzzy theory is applied to representing the degree of fault tree basic events working, and a fuzzy expert system relying on experts´ experience in engineering practice is designed to process the rare information, which is suitable for analyzing fault tree models of complex systems. Eventually, a given example illustrates the process of constructing a fuzzy expert system, and achieving the probability of the fault tree top event. This method describes an opinion of analyzing the fuzzy multi-state fault tree, which is suitable for the safety and risk analysis of a new system in preliminary design phase.