Pipeline safety assessment method for power grid under lightning stroke or grounding short circuit fault condition

Abstract

The invention discloses a pipeline safety assessment method for a power grid under a lightning stroke or grounding short circuit fault condition. The method comprises the following steps: determining the breakdown field strength of soil where a pipeline is located through a test; determining the impact withstand voltage value and the power frequency withstand voltage value of the anticorrosive coating of the pipeline through a test; and finally, judging whether the soil discharge channel can reach the pipeline or not by combining the ground potential rise of the grounding body and the soil breakdown field intensity, and determining whether the voltage of the anticorrosive layer exceeds the tolerance value of the anticorrosive layer or not according to the impact withstand voltage value and the power frequency withstand voltage value of the anticorrosive layer. According to the technical scheme, the safety distance between the pipeline and the grounding device under different conditions can be assessed based on the impact pressure resistance value of the anti-corrosion layer on the basis of the safety assessment.

Description

technical field [0001] The invention relates to electric power engineering technology, in particular to the technology for evaluating the impact of transmission network on pipeline safety. Background technique [0002] Under the condition of lightning strike or ground short-circuit fault, the threat to the pipeline is divided into two ways: [0003] (1) The large value of the current into the ground causes the soil around the grounding body of the tower to be broken down, and the discharge channel of the arc reaches the surface of the pipeline, directly posing a threat to the pipeline. [0004] (2) Under the conditions of lightning strike and ground fault, there is a large potential difference between the soil outside the pipeline anti-corrosion layer and the metal on the inner wall of the pipeline. If the voltage of the anti-corrosion layer is too high, the anti-corrosion layer may be broken down. [0005] To sum up, in order to evaluate whether the pipeline is safe, it ne...

AI Technical Summary

Problems solved by technology

[0003] (1) The large value of the ground current causes the soil around the grounding body of the tower to be broken down, and the discharge channel of the arc reaches the surface of the pipeline, directly posing a threat to the pipeline

[0004] (2) Under the conditions of lightning strike and ground fault, there is a large potential difference between the soil outside the pipeline anti-corrosion layer and the metal on the inner wall of the pipeline. If the voltage of the anti-corrosion layer is too high, the anti-corrosion layer may be broken down

Images