Study on lightning protection measures for distribution lines and customer equipment against back flow lightning current from radio communication station

Recently, with the expansion of communication network areas, the number of radio communication stations, built in the neighborhood of customer houses, has increased. If lightning strikes a communication radio tower, part of the lightning current flows into the distribution line and into customer houses. This may cause the failure of distribution lines or customer equipment. To protect distribution lines and customer equipment from lightning faults, it is necessary to analyze the surge phenomena in distribution lines and customer equipment and take appropriate protection measures. In this study, we examined the effect of lightning protection measures for distribution lines and customer equipment against lightning strikes to a communication tower. First, using an actual-scale test distribution line, we measured the lightning current flowing into distribution lines and customer equipment. Secondly, we quantitatively examined the effect of lightning protection measures by lighting surge analysis while changing each parameter. From the experimental and analytical results, we show that the proposed protection measures can reduce the lightning current flowing into distribution lines and customer equipment. © 2016 The Institute of Electrical Engineers of Japan.