Protection Effect of Oil and Gas Pipeline Insulation Layer Based on Low-Inductive Graphite Composite Grounding Material

The grounding grid using traditional galvanized steel and new low-sensitivity graphite composite grounding tower was modeled and calculated by CDEGS simulation software. The influence of factors such as the distance between the epitaxial grounding body and the pipeline, soil resistivity and other factors on the withstand voltage of the pipeline insulation layer was analyzed, and the dissipation characteristics of the two grounding materials were compared. The simulation results showed that the increase of soil resistivity would increase the voltage amplitude of the pipeline insulation layer. The increase of the distance between the epitaxial grounding body and the pipeline could reduce the overvoltage of the pipeline insulation layer, and the dissipation characteristics of the low-inductive graphite composite grounding under the action of high-frequency current were better than those of galvanized steel. After using low-inductive graphite composite grounding for commutation and drainage, the overvoltage amplitude of the pipeline insulation layer was significantly reduced. An optimization scheme of overvoltage protection using low-sensitivity graphite composite grounding material for lightning current commutation and drainage was proposed.