Study on Protection from Stray Current in the Metro System

Aiming at solving an issue that the stray current increases the risk of corrosion of the buried metal with the increase of operation age in metro, some measures are proposed to protect the buried metal from stray current respectively on the stages of design, construction, operation, and protection in the metro system in this paper. Compared with the reference papers, CDEGS, professional software of grounding analysis, is applied for modeling as well as calculation, and factors are applied to decrease the leakage of stray current with regard to the electrical specification, like different supply modes, voltage classes, and so on. And when the metro is in operation, some measures, like the dust removal, waterproof, and passivation protection should be applied to reduce the risk of corrosion of buried metallic structures. Therefore, with the measures adopted, the risk of corrosion will be reduced greatly.