Reliability analysis of inclined elevator safety braking system based on a fuzzy dynamic fault tree
LU Mingxue
HU Ming
LIN Qingyun
YE Jiekai
LI Wu
ZHOU Qibiao
Abstract：During the operation of inclined elevators,their safety braking systems were identified as key factors affecting the safety and reliability of the equipment.To address the characteristics of dynamic fault occurrence and uncertain fault rate in the safety braking systems of inclined elevators,a reliability analysis method for such safety braking systems based on the fuzzy dynamic fault tree(FDFT)was proposed.The fault rates of the bottom events in the safety braking systems were expressed based on fuzzy mathematics theory.Combined with the dynamic fault tree analysis(DFTA)method,the dynamic fault tree of the inclined elevator safety braking system was divided into static subtrees and dynamic subtrees.For the static subtrees,static OR logic gates were used to solve the fuzzy fault probabilities of events;for the dynamic subtrees,the fuzzy transition rates of different states in the Markov model were adopted to obtain the time-varying failure rate function of the safety braking system.Subsequently,the membership functions of the fault failure probability of the safety braking system at different operation times were derived,realizing the dynamic reliability analysis of inclined elevator systems under the condition of uncertain fault rates.Based on the calculation principle of fuzzy probability importance,the probability importance ranking analysis of the bottom events in the safety braking system was conducted,provided a basis for the regular inspection and maintenance of the safety braking systems of inclined elevators is provided by this research.
Keywords：Fuzzy mathematical theoryDynamic fault treeInclined elevator safety brake systemMarkov modelFuzzy probability of significance
Publication Date：2025-11-15
Online Publishing Date：2026-09-12(First online date of this platform, not the publication date of the document)
Pages：8( 142-149 )