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

Fault tree analysis method is the most widely used methods of system reliability analysis method.Dugan dynamic fault tree analysis method can not describe any forms of static and dynamic failure behaviors,and can not quantitative analysis directly.It needs the help of Markov chain and other tools.Discrete-time T-S dynamic fault tree analysis method makes up for the deficiency of Dugan dynamic fault tree analysis method,but there are analysis and calculation errors,and it can not reflect the continuous change trend of system reliability.Firstly,in order to solve the analysis and calculation error problem of discrete-time T-S dynamic fault tree analysis method,the discrete-time description rule of T-S dynamic gate under the accurate method is proposed;and then,an improved continuous time description rule of T-S dynamic gate is proposed for continuous time T-S dynamic fault tree;further,in order to consider the system reliability analysis problem under working time,working temperature and other factors,continuous-time T-S dynamic fault tree analysis method under multi factors is proposed,which is continuous-time multi-dimensional T-S dynamic fault tree analysis method;Finally,to measure the impact of basic events on top events from more engineering and multidimensional angle,the continuous time T-S dynamic fault tree importance measure analysis method is proposed.Firstly,T-S dynamic fault tree analysis method are studied(including discrete-time and continuous-time).Aiming at the analysis and calculation error of the discrete-time T-S dynamic fault tree analysis method,the discrete-time description rule of T-S dynamic gate under the accurate method is proposed;and then,the continuous time description rule of T-S dynamic gate is improved;compared with the method of solving Dugan dynamic fault tree based on Markov chain,the feasibility of the proposed discrete-time description rules and continuous time description rules for T-S dynamic gate are verified.Secondly,the reliability of complex system is often affected by many factors such as working time,working temperature and so on,while the applicability of continuous-time T-S dynamic fault tree analysis method only considering single factor of working time has limitation.Continuous-time multi-dimensional T-S dynamic fault tree analysis method is proposed,the algorithm of multidimensional input rule and multidimensional output rule for T-S dynamic gate are proposed.Compared with spatial fault tree analysis method and Dugan dynamic fault tree analysis method,the feasibility of the proposed method is verified.Then,to measure the impact of basic events on top events from more engineering and multidimensional angle,,continuous-time T-S dynamic fault tree importance measure analysis method is proposed,including continuous-time T-S dynamic fault tree Fussell-Vesely importance measure,risk achievement worth,risk reduction worth,differential importance measure,integrated importance measure and multi-dimensional continuous-time T-S dynamic fault tree Birnbaum importance measure(probability importance measure),criticality importance measure,upgrading function.Compared with Bell fault tree importance measure and discrete-time T-S dynamic fault tree importance measure analysis method,the feasibility of the proposed method is verified.Finally,the reliability analysis of ice detection system and landing gear retraction and extension system are carried out by using the proposed continuous-time T-S dynamic fault tree importance measure analysis method.The failure probability of the system and importance degrees of each component are solved.The quantitative index of system and component reliability is obtained and the results of the importance degrees are analyzed to provide decision-making basis for system reliability analysis,reliability optimization and fault diagnosis.