Study On Reliability-oriented Preventive Opportunistic Maintenance For High-speed Railway Catenary

With the gradual expansion of the operation scale of high-speed railways and the continuous accumulation of operating hours,the pressure on the operation and maintenance of the contact network has been increasing.The contact network is a no-backup system that is arranged in the open air and is composed of many parts with different properties.With the increase of service time,the components inevitably suffer from problems such as fatigue,wear,and aging,which reduces the reliability of the catenary system.It even caused a breakdown to affect the order of railway transportation.Therefore,in order to ensure the high-speed rail transport quality and efficiency,it is necessary to develop a scientific,reasonable,cost-effective catenary maintenance strategy,to ensure the high reliability of the contact network while reducing the labor intensity of the staff,reduce maintenance costs.In previous studies on contact network maintenance plans,less consideration was given to the reliability differences between different parts of the catenary,nor were the interactions between the various components in the catenary affected.Actually,as a complex system composed of multiple parts,the contact network can adopt an opportunity maintenance strategy,taking into account the reliability of the various parts during operation and the economic relevance of maintenance,and coordinate the preventive maintenance of multiple parts and components together.Apportionment of fixed maintenance costs and outage loss costs,reducing the number of maintenance of the entire contact network,thereby saving maintenance costs,reducing operational risk caused by maintenance,to achieve a unified maintenance of the economy and reliability of contact network maintenance.The main research results of this thesis are as follows:(1)A reliability-centered contact network component preventive maintenance model was established.The Weibull distribution model is used to model and evaluate the reliability of contact network components.Based on the weight analysis of component reliability,the reliability index of the catenary system is assigned and the preventive maintenance time of components is determined.This is used as the contact network zero.The basis for preventive maintenance of components.(2)A model of preventive opportunity maintenance based on reliability margin is proposed.By defining the contact network maintenance reliability margins,a contact network opportunity maintenance model is established;taking the reliability variation rules of the parts as the constraint,and minimizing the total maintenance cost as the decision goal,a contact network preventive maintenance opportunity optimization model is constructed.The quadratic interpolation algorithm is used to solve the problem;the simulation analysis of the example shows that the optimized maintenance decision of the contact network opportunity can effectively reduce maintenance times and maintenance costs.(3)A preventive opportunity maintenance model based on reliability sensitivity of the catenary is proposed.The interval number is used to describe the contact network opportunity maintenance model and the sensitivity of the contact network components;the minimum total maintenance cost is taken as the optimization goal,and the reliability reliability of the parts and the overall reliability of the contact network are taken as the constraints to establish a contact network preventive opportunity maintenance.The optimization model is solved by using more researched genetic algorithms.The simulation analysis of the example shows that the maintenance decision made under this optimization model can achieve the effect of opportunity maintenance,taking into account the reliability sensitivity of the parts and more in line with the actual maintenance requirements of the site.