Method for assessing lightning flashover risks of regional power grid lines

Abstract

The invention discloses a method for assessing the lightning flashover risks of regional power grid lines, which comprises the following steps that: through calculating the lightning-resistant level of each base rod tower and combining with a probability distribution function of lightning current amplitudes of a region, the lightning trip-out rate of each rod tower is obtained, and the average lightning trip-out rate of a line is calculated; then, through combining with an automatic reclosing failure rate and a failure rate of manual forced energization, a permanent failure rate of the line is obtained; and through considering the weight coefficient of the line in a power grid structure, the permanent failure load loss coefficient of the line at the specific time of a power grid and in an specific operation mode of the power grid, and the risk occurrence probability of other influencing factors, a lightning flashover risk assessment model of a regional power transmission grid is established. According to the invention, the shortcoming that the absolute numerical value of the lightning trip-out rate can not really reflect the lightning disaster risk level of each line is overcome, and the lightning flashover risk level of each rod tower of lines is assessed through comprehensively considering the differences among the lightning motions, topographical features, line structures, insulation configuration, lightning protection measures and the like of each line corridor in the power grid, so that more comprehensive and thorough assessment results are obtained.

Description

technical field [0001] The invention relates to a lightning flashover risk assessment method for transmission lines of regional power grids based on lightning location data. Background technique [0002] At present, there are few studies on lightning flashover risk assessment of power grid transmission lines. Generally, the lightning trip rate is used as the evaluation index, and the line with a high trip rate is considered to be a line with a high risk of lightning flashover. According to the power grid operation experience, although the number of line trips caused by lightning strikes is large, the proportion of unplanned outages is lower than that of trips due to the high reclosing success rate of automatic reclosing devices. The main reason is that the lightning trip is an instantaneous fault of the power system. After the insulation of the fault point is restored, the automatic reclosing is generally successful, and the possibility of the lightning trip turning into a p...

AI Technical Summary

Problems solved by technology

The lightning trip rate is a characteristic parameter that effectively reflects the source of the lightning risk of the power grid. However, since the lightning trip may not cause serious consequences such as interruption of power supply and other permanent failures of the power system, the absolute value of the lightning trip rate cannot truly reflect the lightning disaster of each line. Risk level, the lightning flashover risk assessment of the transmission network should consider the comprehensive assessment of a series of losses caused by the operation of the power grid and power transmission and transformation equipment after the line is tripped by lightning, in order to obtain a more comprehensive and detailed assessment result

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