Study On Stray Current Interference Range And Monitoring Method In Metro Depot

As an indispensable part of the urban rail transit system,the metro depot carries the important functions of daily parking and maintenance of trains.However,due to its complex structure,numerous equipment,poor working environment and other factors,the insulation capacity of the depot is poor.Therefore,the stray current interference degree of the depot is often more serious,and its interference range is wider,which is more likely to pose a threat to the metal facilities such as structural reinforcement and buried pipelines in and around the depot.Therefore,it is of great significance to study the interference range and monitoring method of stray current in the depot for preventing the possible harm caused by stray current in the depot.In this thesis,theoretical model derivation,3D software simulation,machine learning algorithm,experimental test verification and other methods are comprehensively used to carry out research on the relevant laws,influencing factors and monitoring methods of the stray current interference range in the depot.The main research work is as follows:(1)Introduced the basic structure of the vehicle depot and the mechanism of stray current generation,combined with the structure of the vehicle depot reflux system,established a vehicle depot stray current interference range model based on surface potential gradient,and established a three-dimensional topology model of the vehicle depot based on CDEGS simulation software.The distribution pattern of surface potential gradient around the vehicle depot under the interference of stray current was simulated and analyzed,as well as the interference range of stray current,and the simulation results of two types of models were compared to verify the accuracy of the three-dimensional topology model.(2)The influencing factors of the interference range of stray current in the depot are analyzed and summarized,and then an indirect monitoring method of the interference range of stray current in the depot based on random forest is proposed.The gradient value of Surface potential at each point around the depot is predicted through the random forest model.The prediction results of the model show that the accuracy of the model is high,which proves the feasibility of the monitoring method of stray current interference range in depot based on random forest.(3)A stray current interference range monitoring system is built for rolling stock segment.The software and hardware of the monitoring system are designed and developed to realize the AD acquisition and network communication of surface potential gradient,and the upper computer software is designed to realize the real-time monitoring of stray current in rolling stock segment,historical data query and interference range evaluation.(4)Set up a simulation test bench for the depot,and verify the influence of various relevant factors on the interference range of stray current in the depot through experiments.At the same time,obtain data sets and train the random forest model based on the test bench,and verify the accuracy of the prediction model and the feasibility of the monitoring method for the interference range of stray current based on the model.This thesis has 69 pictures,10 tables and 89 references.