Influence of power tower grounding on adjacent oil and gas pipelines

Abstract

In order to study the influence of electrical power towers on the nearby natural gas pipelines and the protective measures when lightning strikes power towers, a power line and natural gas pipeline model was established with the professional lightning protection calculation software CDEGS, and the influence of grounding grid with a single approaching, departing and parallel epitaxial ray on the potential of pipelines was studied under different influencing conditions of current amplitude, soil resistivity and distance. Further, a pipeline overvoltage optimization scheme based on the forced commutation was proposed. The results show that, the increase of soil resistivity and current amplitude will lead to the increase of pipeline overvoltage, and increasing the distance between the power tower and the pipeline can reduce the pipeline overvoltage. With the increase of the redirection angle of the epitaxial rays, the overvoltage on the pipeline and the potential difference suffered by the coating show a decreasing trend. Generally, the forced commutation based optimization scheme proposed herein could significantly mitigate the lightning overvoltage risk of power lines to the adjacent natural gas pipelines.

Keywords

• natural gas pipeline
• grounding grid of power tower
• lightning overvoltage
• forced commutation
• structural optimization