Study On Reliability Analysis And Maintenance Mode Decision Of Metro Train Bogie System

Metro has become one of the most effective tools to solve the problem of urban traffic congestion,because of its characteristics of fast speed,large capacity,timely reliability,energy saving and environmental protection.As the carrier and the core part of metro transportation,improving its reliability and reducing its maintenance costs are the key to ensure the safety and economic operation of metro.Bogie system is the key subsystem of metro train,so researching its reliability and maintenance mode decision is of great significance to improve the reliability of metro train and reduce the maintenance cost of metro train.Therefore,this paper research the reliability analysis and maintenance mode decision of A2 bogie system of Guangzhou Metro,and the main research results and methodological processes are as follows:(1)Based on the research on the function,structure and failure mode and effect analysis of the bogie system,the fault tree model of the metro train bogie system is constructed.(2)The Bayesian network model of the metro train bogie system is constructed combined with fuzzy set theory to analyze the reliability of the metro train bogie system.Firstly,the transformation modeling method of fault tree model to Bayesian network is studied,by which the fault tree model of metro train bogie system is transformed into Bayesian network.For the problem that fault data of the bogie system is incomplete and the accurate fault probability cannot be obtained,the fuzzy set theory is used to estimate the prior probability of the root nodes.And,the Noisy-Or model is used to correct the conditional probability of some intermediate nodes,which greatly reduces the number of parameters that need to be given when constructing the conditional probability distribution.After the complete Bayesian network model of the metro train bogie system is obtained,the joint tree inference algorithm is used to calculate the posterior probability,probability importance and key importance of the root nodes,which provides help for the weakness discovery and the maintenance work of the metro train bogie system.(3)A method for maintenance mode decision of metro train bogie system based on cloud model and VIKOR is proposed to determine the maintenance mode of each components of the metro train bogie system.Firstly,studying the various factors affecting the maintenance importance of bogie system components,and the importance evaluation index system of bogie system components is constructed from three aspects of reliability,maintainability and economy.In order to fully consider the fuzziness and randomness factors in the evaluation process,the cloud model is used to quantify the qualitative evaluation language.Then the expert weights are obtained by calculating similarity degree between cloud models to collect the evaluation information.The analytic hierarchy process and the cloud model-entropy method are used to determine the index weights,and the VIKOR method is used to obtain the maintenance importance of the components.In this way,the importance evaluation model of the components of the metro train bogie system is constructed.Finally,the components of the metro train bogie system are classified based on the maintenance importance,and the maintenance mode of each components is determined according to the logic decision diagrams.(4)The reliability analysis and maintenance management system of the metro train bogie system was developed by Java,which has the functions of system management,fault data management,maintenance planning management,FMEA management,reliability analysis based on Bayesian network,importance evaluation of components and maintenance mode decision.This system can offer help to fault data management and routine maintenance work of the metro train bogie system.