221 / 2022-03-14 19:57:05

Investigation of Electromagnetic Pollution Control Method in Urban Rail Transit Tunnel

urban rail transit; tunnel model; electromagnetic coupling; induction voltage;

In order to cope with the expansion of urban population, and meet people's daily travel needs, a number of major cities in China have newly opened the 27.5kV AC power supply system of urban rail transit lines.AC power supply system of the subway tunnel due to the ac space coupling and the effect of alternating current, can cause the change of the earth potential, stray current will produce electrochemical corrosion around the track buried metal components, shorten the service life of metal pipeline, reduce the strength and durability of subway reinforced concrete main structure, cause unnecessary equipment and economic losses.The change of the earth potential is reflected in the potential difference between the substations, resulting in the DC partial magnetic phenomenon of the neutral point of the transformer.The overall simulation model of the tunnel is established, the electromagnetic pollution in the tunnel is calculated, and the influencing factors and influence rules of the induction voltage of the metal structure in the tunnel are obtained. From the two aspects of ground coupling and electromagnetic coupling, the scheme of structural reinforcement, drainage network and reflux line is found.