Continuous-time Multi-state T-S Dynamic Fault Tree Analysis Method And Its Applications

The failure modes of large-scale equipment systems are intricate,and it has uncertain characteristics,static characteristics,dynamic characteristics,multi-state characteristics,etc.The reliability analysis of such system has become the focus of academic research.The fault tree analysis approach is the most commonly employed technique in analyzing systems,which can vividly depict the failure relationship,failure behavior and improvement direction of the system.The current approach for T-S dynamic fault tree analysis can effectively capture the system’s uncertain,static and dynamic failure characteristics,but the analysis method can not capture multi-state features.Therefore,a method for analyzing continuous-time multi-state T-S dynamic fault tree and importance are introduced.Firstly,the multi-state problem is described through the description of each event state,defines and proposes multi-state T-S dynamic gate to describe the static and dynamic relations of multi-state events,and proposes the method of continuous time event timing description rules of multi-state T-S dynamic gate by introducing order rules and impulse functions.It can describe the failure behavior of any form of the system with multi-state characteristics.Secondly,the fault probability distribution function of the superior event is analyzed,and the reliability data of the event is combined with it to obtain the calculation method of the multi-state T-S dynamic gate event time sequence description rule,which can be used to solve the reliability index of the system.The validity of continuous time multi-state T-S dynamic fault tree analysis method and its advantages are verified by comparing with static and dynamic fault tree analysis methods respectively.Then,an algorithm for assessing the importance measures of continuous time multi-state T-S dynamic fault tree is proposed.The importance measures of basic events to the system in different fault states can be obtained by putting in the probability of basic events fault.The effectiveness and feasibility of the continuous-time polymorphic T-S dynamic fault tree importance analysis method are verified by comparison with the importance method of the polymorphic T-S dynamic fault tree.Finally,the continuous-time multi-state T-S dynamic fault tree and its importance analysis method were employed to analyze the reliability of the air supply system and communication interface unit system of the EMU.The faults of the system in various fault states were determined.And identify the most important events that cause system failures,the basis for the improvement of system reliability can be provided.