An online monitoring method for transmission line tower grounding resistance

Abstract

The invention provides an online monitoring method for a grounding resistance of a transmission line tower, which is realized by a transmission line monitoring device, a lightning positioning system and a grounding resistance online monitoring system, and specifically comprises the following steps: S1, determining whether a lightning strike failure occurs; S2, calculating a total amount of chargeof the lightning strike current when the lightning strike failure occurs; S3, separately calculating the amount of leakage current charge in four directions; S4, calculating the amount of leakage current charge entering the ground in the direction of the tower; and S5, calculating a proportional coefficient between the amount of charge transmitted by the lightning strike current in the direction of the tower and the total amount of charge of the lightning current, and determining whether the grounding resistance meets the grid standard. According to the online monitoring method for the grounding resistance of the transmission line tower, the grounding resistance of the transmission tower hit by each lightning current can be monitored in real time, the judgment error caused by the change ofthe historical grounding resistance of the tower due to factors such as insulation degradation can be avoided, and a real time comprehensive monitoring of the grounding resistance of the transmissionline can be realized.

Description

technical field [0001] The invention relates to the field of transmission line fault identification, in particular to an on-line monitoring method for the grounding resistance of transmission line poles and towers. Background technique [0002] In the power system, in order to meet the needs of safety and work, it is often necessary to connect certain positions of electrical equipment to the earth, which is grounding. Compared with transmission lines, lightning strikes are the main factor causing line trips. According to incomplete statistics, lightning strikes and tripping faults of transmission lines account for 40% to 60% of the entire transmission line tripping faults. Therefore, it is necessary to increase protection against transmission lines. Lightning protection measures, and grounding transmission line towers is one of the important means of lightning protection measures. For the size of the grounding resistance of transmission line towers, the power grid has expre...

AI Technical Summary

Problems solved by technology

[0004] According to the analysis of the current status of the grounding resistance measurement of the transmission line pole tower, the current measurement applicability of the pole tower grounding resistance is not high. It has strong limitations. Grounding resistance measurement is mostly offline measurement, which has gradually failed to meet the needs of the current power grid.

Images