Study On The Monitoring And Protection Scheme Of Stray Current In Lanzhou Subway Line

Subway for the advantages of convenient,efficient,safety and the large volume occupies the important position in Urban Rail Transit.Along with the rapid development,there are also some problems to be solved that threaten the safety of the subway system.The Stray Current leakage problem is harmful to the subway system,in the process of DC high voltage power supply.In this thesis,Lanzhou Rail Transit Line 1 is the engineering background to analyze the stray current monitoring and protection scheme of Lanzhou Rail Transit Line.(1)The formation and harm of stray current in subway are analyzed in this thesis.(2)Mathematical modeling is conducted according to the circuit theory for the system with drainage and no drainage,and MATLAB is used for simulation analysis.(3)Building the simulation experiment platform of the stray current forming,having been the main factors influencing the stray current leakage through the comparative analysis of the actual test and theoretical study,providing theoretical basis for the protection scheme.(4)The passive and active stray current protection scheme is proposed.(5)Analyzing the features of the line 1 and the particularity of stray current,putting forward the stray current protection and monitoring plan of "wall" passive supplemented,the initiative to "row" and the monitoring,from Lanzhou Rail Transit Line 1 project construction practice.This thesis analyzes the main factors influencing the size of the stray current leakage on the basis of theoretical modeling simulation and experimental testing,puts forward the stray current protection and monitoring scheme according to the characteristics of line 1,provides the theoretical basis for stray current protection and monitoring of the Lanzhou Rail Transit Line 1,and has the vital significance to ensure the safe operation of the late vehicle.