Evaluation of Characteristics of Lightning Faults on 275 kV Transmission Lines

摘要

It is effective to design the lightning protection of transmission lines by employing simulation to be able to reproduce conditions of experienced lightning faults. As a result of the lightning faults on 275 kV transmission lines in Hokuriku area, the frequency of only one-ground fault of upper or middle lines is higher. Especially, the frequency of one-ground faults of the middle lines in summer is the highest. It is thought that many one-ground faults in summer are caused by direct lightning strokes to phase conductors. Moreover, multi-ground faults caused by lightning strokes to tower tops or overhead ground wires also include many ground faults of the middle lines. In this paper, the experienced lightning faults on the 275 kV transmission lines are reproduced by EMTP calculations and the characteristics of the ground-fault lines are examined.