Study of transmission line AC interference with steel-buried pipelines under lightning strikes

When lightning strikes the transmission line tower, the lightning current flows into the soil along the tower grounding device, causing serious AC interference with nearby steel-buried pipelines. To tackle this problem, this paper uses CDEGS, the professional power analysis software, to establish a three-dimensional (3D) simulation model for the transmission line and surrounding pipelines based on the actual engineering information. This model predicts the coating stress voltage of steel pipelines in public corridors when typical lightning strikes towers. Lightning current includes the first return and subsequent return strokes. Resistance and inductance couplings are considered in the calculation. In addition, the paper uses COMSOL Multiphysics software to calculate the distribution of potential and current density on the surface of adjacent pipe under the first lightning return stroke, providing a new analysis idea for mitigating the AC interference caused by the lightning current. The conclusions of this paper can be used as a reference for the analysis of transmission line AC interference with adjacent steel-buried pipelines in lightning strikes.