Numerical simulation of stray current distribution in metro network with drainage
                                                     MA De liang, FANG Jiang min, QIAN Yao hong
         （School of Mechanical and Automotive Engineering, South China University of Technology, Guangzhou 510640, China）

Abstract: Aiming at the corrosion and prevention of stray current in the subway, the influence distribution of the stray current and related factors of the subway is studied. on the basis of the existing rail metal mesh model, the physical model of the rail drain network metal mesh system was proposed and established.Based on Kirchhoff s Law, the corresponding mathematical model is established, Matlab was used for programmingthe mathematical model, the effect of the drainage network and the influence of the distance between the substation, the transition resistance and the longitudinal resistance of the running rail on the running rail current, the running rail voltage, the stray current and the current in the drain network are studied respectively. The results indicate thatdrainage network can drain most of the stray current, thereby reducing the corrosion hazard; substation spacing should not be greater than 2 km, the transition resistance should be set at 15 Ω·km or more, the longitudinal resistance of the track should be reduced as much as possible.

Key words: stray current; metro; drainage net; rail; transition resistance