Abstract
In Japan, lightning damage to FRP blades of wind turbine generators has been increasing in parallel with the recent increase in the installation of wind turbine generators. Therefore, we established a test method, while clarifying the destructive climate of lightning, and examined a method of preventing destruction.
A high-voltage test clearly showed that lightning easily penetrates FRP that is not processed to be conductive. Moreover, after developing a test method, an examination with a large current successfully reproduced blade damage, and revealed the failure mechanism, which explains breakdowns of actual machines. If lightning penetrates a FRP blade, the air temperature inside the blade rises. As a result, pressure increases and the blade is damaged. Moreover, the breakdown of positive polarity (winter) lightning can be examined with a large current that is generated by a short circuit generator.
