Research On Route Optimization Method Of Railway Station Shunting Operation

The shunting operation plays an important role in the transportation and production activities of railway stations,especially in marshalling stations or enterprise railway stations.The scheduling and distribution of route is one of the key factors affecting the operation efficiency of the whole station.However,there is not yet a set of efficient route allocation methods,which are mainly selected by dispatchers according to the operation plan in real time.Because the level of personnel directly affects the quality of route allocation,it is easy to cause conflicts between operations,resulting in low efficiency of operation execution.Therefore,this thesis studies the route allocation optimization problem in the execution stage of shunting operation,introduces the method of job-shop resource scheduling,and puts forward the corresponding optimization method.The main work of this thesis includes:(1)The shunting operation process was analyzed.Combined with the shunting operation execution process,the operation plan is decomposed into sub-item operations as the basic scheduling object in the model.An approximate calculation method of route resource occupancy time based on traction calculation is proposed.Based on the traction calculation theory,the least square method is used to fit,and the time-distance calculation function is obtained.This method can accurately calculate the occupancy time of track section on the route under the condition of section releasing.(2)The optimization model of route allocation based on job-shop resource scheduling is constructed.The optimization objective of the model is to reduce the total running time of locomotive trains and the total delay time of sub-operations.The scheduling sub-operations are abstracted as the process of machining workpiece by machines,and various complex constraints are constructed to avoid the temporal and spatial conflicts between operations by comprehensively considering the topological relationship of lines,the operation plan and the influence of section releasing of interlocking.The corresponding dynamic adjustment method is proposed for the interference events such as new operation,track fault and operation delay in the operation process.(3)A hybrid genetic algorithm based on variable neighborhood search is proposed.According to the characteristics that the model is difficult to solve,based on genetic algorithm,a bi-level encoding and decoding scheme of sub-operation sequence scheduling and route selection is proposed,and the genetic operation is designed according to the characteristics of route allocation problem.Neighborhood structures are designed for operation scheduling sequence and route selection to enhance local search capability;this algorithm can obtain satisfactory route allocation scheme in a short time.(4)The simulation experiment of shunting operation route optimization was carried out.The proposed method is applied to route scheduling,and the experimental results show that the value of the weight factor in the optimization objective affects the route allocation results.Section releasing mode can make full use of station equipment capacity than one-time unlocking mode;compared with the existing methods,the proposed method has better optimization effect in both travel time and delay time.Three dynamic scene experiments verify the effectiveness of the proposed adjustment method.In this thesis,combined with the operation plan of the transportation scheduling layer and the route of the route control layer,an optimization method of shunting route allocation based on job-shop resource scheduling is proposed,which improves the quality of route allocation and reduces the burden of dispatchers.This study has certain reference significance for the follow-up research on shunting operation optimization.This thesis includes 31 figures,23 tables,60 references.