Seasonal Characteristics of Lightning Strokes to Distribution Lines in Hokuriku Area

Abstract

The proportion of the lightning outages in all outages on 6.6kV overhead distribution lines is high with approximately 20 percent in Hokuriku area, and then the lightning protection is important to prevent the outages. Several evaluation methods of lightning protection measures of distribution lines have been proposed. However, the frequency of lightning strokes to distribution lines is not accurately considered in these methods, particularly in winter. In order to find out the actual frequency of lightning strokes to distribution lines, we have observed lightning channels using lightning-video cameras at Tonami plain in Hokuriku area. If a lightning channel is recorded by two or more video cameras located at different points, it is possible to locate a lightning stroke point by direction finding method. In this paper, we present the observation data of lightning channels recorded by the video cameras from November 2016 to October 2019. First, we evaluate the location errors of the video cameras. Then, since it is confirmed that the lightning stroke points can be accurately located by the video cameras, we estimate the frequency of lightning strokes to distribution lines by season from observation data.