Study on the Methods to Inhibit Potential Rise of Buried Oil and Gas Pipeline When Lightning Strikes on the Line Tower
Lightning strikes on the transmission line tower will cause the potential rise of buried oil and gas metallic pipeline(BMP), which will break through the coating of BMP and cause pipeline corrosion. It is of great significance to study on the methods to inhibit potential rise of BMP when lightning strikes on the line tower. A line-tower-grounding device-buried pipeline system simulation model is established by CDEGS software, which can comprehensively consider the inductive coupling of the lightning current on the overhead ground wires to BMP and the resistive coupling of the lightning current through the tower grounding system to BMP. The effects of the soil resistivity, the distance and the crossing angle between the line and BMP on the potential rise of BMP are studied. In addition, based on the simulation, the design and transformation methods of grounding system which can effectively inhibit potential rise of BMP are proposed. The research results of this paper can provide a guidance for the protection of BMP against lightning.