Research on the Elevator System with Fault Diagnosis Method Based on Fuzzy Fault Tree

Abstract

This paper is aimed at the security problems of elevator system.Fuzzy fault tree analytic method is applied to study the reliability of the elevator system.First of all, the elevator system is divided into four subsystems, and then the paper take elevator fall accident as the top event as a example, applying the ascending method for qualitative analysis to find out 7 minimum cut sets in the fault tree and 15 bottom event structure importance sorting. Finally, the fuzzy fault interval probability come out through introducing the concept of fuzzy number in fuzzy set theory, using the triangular fuzzy number to describe the probability of basic event occurrence in the fault tree, making an quantitative interval probability calculation in middle events and top events in the fault tree..The results show that the fuzzy fault tree is an effective and practical method for reliability analysis when we are difficult or unable to obtain the accurate probability of bottom events in terms of the elevator system. Compared with the traditional method of fault tree, the calculated result is more scientific and reasonable, closer to the engineering practice.