Research On Optimization Of Maintenance Plan For Railway Catenary System Based On Risk Assessment

Catenary system is a huge power supply device without spare in nature.Because of the complex structure and poor working condition,the failure of catenary system is the primary cause of power supply interruption in traction.Currently,the strategy of fixed cycle repair is used to making catenary system maintenance plan.Under the premise of the stable transportation,how to reduce the maintenance cost of the catenary is an important subject for railway departments and technical personnel.Firstly,the structural composition of catenary system is analyzed by using fault Petri net qualitatively.Taking the equipment failure rate and maintenance factors on system reliability into account,a new method for calculating the dynamic reliability of catenary system is proposed by the GO-FLOW method.The fault loss is defined by the interval analysis method,and the failure risk assessment method of catenary system is determined.Secondly,on the basis of risk assessment of catenary system,a single objective optimization model,taking the minimum the maintenance cost as the optimization objective and the restrictions of risk cost and repair resources as the constraints,is built.To solve the optimization problem,a genetic particle swarm optimization algorithm is designed.Case study validates risk maintenance strategy can reduce maintenance costs.At the same time,both reliability and fault risk of the catenary system can be controlled compared with the maintenance plan optimization based on reliability.Finally,in order to further illustrate the superiority of risk maintenance optimization,a multi-objective optimization model,taking the minimum the maintenance cost and risk cost as the optimization objective and the restrictions of repair resources as the constraints,is built.A multi-objective particle swarm optimization algorithm based on chaotic Kent map and niche technology with good convergence is designed for the same case.In the process of calculation,the improved multi-objective particle swarm optimization algorithm is compared with the basic particle swarm optimization algorithm.A good optimization result with less maintenance cost and risk fluctuation can be obtained.The example results verify the model and algorithm are feasible and effect.A new way for the optimization of the catenary system maintenance plan is proposed and has good value in engineering.