がいしの塩汚損が配電線直撃雷によるスパークオーバ発生率に与える影響

抄録

To improve the lightning-outage-rate calculation method of medium-voltage distribution lines, it is important to accurately assess sparkover rates of insulators. In salt polluted areas, lightning outage rates may increase due to the deterioration of insulation performance of insulators. Although the sparkover characteristics of salt-polluted insulators against the standard lightning impulse voltage have been reported in previous works, the sparkover characteristics against short-wave-tail lightning impulse voltages, which occur across insulators on distribution lines by direct lightning strikes, still remain not clarified.

In this paper, first, we experimentally study the sparkover characteristics of salt-polluted insulators against a short-wave-tail lightning impulse voltage. Second, using the measured sparkover characteristics, we evaluate the influence of salt pollution on the sparkover rate of medium-voltage distribution lines due to direct lightning strikes.