Leakage Location of Stray Current in Rail Transit Based on Differential Evolution Algorithm

With the acceleration of urban construction, the subway system and the urban power grid system are too close in the dense urban system. There is a big problem in the operation of subway system, that is, the load current will enter the ground from the weak insulation of the track and invade other public network systems, causing a series of adverse effects such as corrosion. For the power grid, the stray current leaking to the ground will be attracted by the AC power grid, which will make the neutral DC current of the grounding power transformer around the rail transit line change significantly. In order to obtain the intensity and location of stray current leakage point, this paper proposes the inverse location of current leakage point through the distribution of DC current in the neutral point of transformer in AC power grid. In this paper, the mathematical model of point leakage point is constructed to replace the line leakage section, the stray current leakage is monitored by the transmission network, and the actual situation of track insulation damage is reflected by analyzing the distribution characteristics of transformer neutral point DC current, which makes the maintenance and repair work of rail transit more targeted.