Analysis of Stray Current Intrusion into Grid Substation under Multiple Factors

In modern cities, with the continuous intensification of subway lines, the impact of the stray current generated on the power system is constantly expanding, becoming a potential threat to the stability of the power supply of the power system. As a coupling channel between the subway system and the power grid system, different soil structures have a profound impact on the distribution of stray currents. In this paper, a coupled finite element model (FEM) of a single subway line and a power system is constructed, and the distribution characteristics of stray currents under different soil structure conditions and traction conditions are studied. The results show that different soil structures affect the surface potential distribution around the subway and affect the neutral point current of the transformer.