Operation Reliability Assessment Of Catenary Based On Bayesian Network

As the core part of electrified railway,catenary undertakes the important task to provide continuous power to electric locomotive,which is the only directly dynamic power source.The reliability of catenary not only affects the full play of the advantages of electric traction,but also directly relates to the stability and safety of the train operation.The research and analysis of the reliability of catenary has important significance in ensuring the safety of the train operation,as well as improving the operation quality of electrification railway and the economic benefit.According to the fault data of catenary in actual survey,Bayesian Network method is used to the analysis and assessment of the reliability of catenary.Firstly,through the statistics analysis of the fault data,the reliability indexes of main components of catenary are calculated and the Fault Tree model of catenary is established.Then basing on that,Baysian Network model of catenary system is established.According to the model,using exact inference algorithm,the reasoning of the reliability of catenary system is analyzed.The failure probability of in-service catenary system is calculated and the weak link of the reliability of catenary system is diagnosed.At the same time,the reliability indexes of the catenary system are calculated.Secondly,the reliability of the key components which are in the weak link of catenary system according to the above analysis is analyzed and assessed using Bayesian Network method.The failure probability and the main fault factors which influence the reliability of the components are obtained.Based on the monthly statistical analysis of the failure of the key components,the monthly(seasonal)characteristics of the component failure are studied.Combined with the result of the above analysis and the investigation knowledge,the common fault factors which affect the reliability of components and the prevention and control measures are described and analyzed.According to the previous analysis,thoughts and suggestions improving the reliability of catenary are given.Finally,the reliability distribution of catenary system is studied.Fuzzy Comprehensive Evaluation method is used in the reliability allocation of the catenary system considering several factors that affect the system reliability allocation;using the characteristic of Bayesian Network backward inference that the conditional failure probability can reflect the effect of components on the system reliability,Bayesian Network method is used in the reliability allocation,taking the contact suspension subsystem as an example,the reliability allocation of its components is completed.