Distribution Engineering Research Section
Distribution system is widespread electric power facility which is installed near electricity consumers. It is necessary to mitigate the damage of distribution equipment due to natural disasters, in the view point to reduce both of system development cost and operation cost, keeping system reliability. In addition, planning of the countermeasure against lightning is one of the most important issues. Thus, the purpose of our research is the optimization of system configuration based on lightning frequency by region in Hokkaido.
Our detailed examination of distribution line equipment found many defects in concrete electric poles having metal bands, showing impacts by direct lightning.

Photo-1 State of the defect in concrete

Fig-1 Rate of the defect in concrete electric poles

Fig-2 Principle of the defect in concrete by direct lightning
In the future, we will aim to present lightning-resistant measures in consideration of the properties of lightning by region in Hokkaido, by investigating actual damage to equipment and the correlation with lightning information by lightning location and protection system (LLP).