Case Analysis of Electromagnetic Interference of Lightning Strikes onHigh-Voltage AC Transmission Lines on Adjacent Buried Oil & Gas Pipelines

In order to study the electromagnetic interference of lightning strikes on high-voltage AC transmission lines on adjacent buried oil and gas pipelines, an electromagnetic interference model of transmission lines and adjacent buried oil and gas pipelines in a domestic field case was established by using SES CDEGS numerical simulation software, and the interference caused by lightning current on pipelines was calculated and predicted based on the established model. The risk assessment indexes for the electromagnetic effect of lightning current on pipelines were established from three aspects, including personal safety, pipeline coating breakdown risk and pipe wall arc melting risk, based on the investigation of relevant standards and research results at home and abroad. The risk level of field case was evaluated using the obvious risk assessment index, and the effects of soil resistivity and tower grounding grid structure on the pipeline overvoltage and the leakage current from grounding conductor were calculated and analyzed. The results showed that the pipeline safety risk caused by lightning current was low in the field case, and the soil resistivity had a significant effect on the pipeline overvoltage and the leakage current from the grounding grid conductor, which increased with the rise of soil resistivity. When using a horizontal grounding grid, the structure of the grounding grid had little effect on the pipeline overvoltage and the leakage current from grounding grid conductor under the precondition of the same surface area of grounding grid. Vertical grounding electrode could relieve pipeline overvoltage, but the number should not be too much.