A Field Study of Lightning Overvoltages in Low-Voltage Distribution Lines

摘要

The number of home electric appliances, such as personal computers and telephones, has been rapidly increasing. Lightning damage to these home electric appliances has a great impact on a highly sophisticated information society. There are cases in which lightning over-voltages in low-voltage distribution lines cause malfunctions in them, even though they are equipped with surge protective devices to protect against lightning over-voltages. Therefore, for lightning protection of low-voltage equipment including home electric appliances, it is important to understand the phenomenon of lightning over-voltages in low-voltage power distribution lines. However, many aspects of this problem are not entirely clear, in particular how they are generated. The Tokyo Electric Power Company carried out lightning observations on low-voltage distribution lines. The observation results provide a statistical distribution of lightning over-voltages in low-voltage distribution lines. A mechanism for generating lightning over-voltages in low-voltage distribution lines is inferred from the observed waveforms and facilities data.