Research On Rolling Stock Operation Planning Considering Dynamic Maintenance Demand

By the end of 2020,the mileage of high-speed railway in operation in China reached37,900 km,which has become the country with the most mileage of high-speed railway in operation.As the most important mobile equipment of high-speed railway system,it has the feature of expensive cost,so it is important to study the operation plan of rolling stock to improve the operation efficiency of rolling stock and reduce the operation and maintenance expenditure of high-speed railway.Preventive repair is an effective means to ensure the safety of rolling stock operation,and the operating efficiency of rolling stock is greatly influenced by the repair process and repair class and repair system.From China’s more than ten years of experience in the use of high-speed railway rolling stock,China’s rolling stock repair class and repair class and repair system has greater room for optimization,and has begun the latest round of repair class and repair class and repair system reform,in the maximum effectiveness of the equipment,the implementation of reliability-centered maintenance ideas,China’s high-speed railway rolling stock maintenance system will achieve a comprehensive change from planned to state repair,when the formation of dynamic variable maintenance needs.Before the reform of the maintenance system of the rolling stock,the same type of rolling stock adopts a fixed maintenance cycle,but under the dynamic maintenance demand,the maintenance mileage and time of different rolling stock trains are different,at this time there will be a new way of using the rolling stock,and the problem of the preparation of the rolling stock operation plan.In this paper,we study the problem of preparing the rolling stock operation plan considering the dynamic overhaul demand.The specific research contents are as follows.(1)analysis of dynamic maintenance needs under the use of rolling stock method.First,on the basis of the analysis of China’s existing rolling stock maintenance system,further analysis of the trend of rolling stock repair process and system reform,so as to put forward the issue of dynamic maintenance of rolling stock operation planning.Then,the focus on the dynamic maintenance needs of rolling stock operation mode and rolling stock operation plan preparation cycle,and analysis of dynamic maintenance state rolling stock operation plan preparation method,analysis of the impact factors of rolling stock operation plan preparation.Finally,the overall structure of high-speed railway rolling stock utilization optimization is elaborated,and the status and role of rolling stock operation plan in the rest of railway transportation plan is summarized.(2)To establish a model of rolling stock operation plan under dynamic maintenance demand,in order to generate a rolling stock operation plan that meets the lowest cost of rolling stock operation.First of all,to build a dynamic maintenance demand consideration of the space-time network of rolling stock utilization,the lowest cost of rolling stock utilization as the objective function,mainly considering the rolling stock maintenance constraints,demand constraints,rolling stock type and train running line coupling constraints,rolling stock utilization capacity,rolling stock succession time and other constraints,to establish the general space-time network model of the rolling stock utilization problem.Then,based on the space-time network model of rolling stock utilization,the space-time network modeling method is extended to introduce the state dimension to represent the maintenance state of rolling stock,and the lowest cost of rolling stock utilization is the goal.(3)Design the solution algorithm of the rolling stock operation planning model.Firstly,we analyze the determination method of rolling stock operation planning period under dynamic maintenance demand.Then,the graph theory method is applied to pre-process the train timetable lines,transform the nodes of the train timetable lines that need to prepare the rolling stock operation plan,and search all feasible successive crossings of each rolling stock by using depth-first traversal under the condition of considering the maintenance status and succession time constraints of the rolling stock.Finally,based on the set decomposition model,we construct a rolling stock allocation model with the objective of minimizing the operating cost of the rolling stock after allocating the rolling stock to feasible crossings,and use Gurobi to solve the rolling stock allocation model to obtain the rolling stock operation plan.The solution with the smallest objective function is the final rolling stock operation plan.(4)The correctness of the model and algorithm are verified by simple and large-scale cases.For the two different scale cases,the rolling stock operation plan is prepared for the two cases of fixed maintenance and dynamic maintenance,and the calculation results obtained in the two cases are compared and analyzed.The above research is not only important to improve the preparation level of the dynamic maintenance requirements of the rolling stock operation plan and realize the intelligent level of the rolling stock operation plan,but also has reference value for the research and design of the decision support system of the high-speed railway rolling stock operation plan preparation.