Experimental Study on Lightning Attachment Manner to Rotation Wind Turbine Blade

Lightning strike is one of the most serious damages to the wind turbine blade. The blade is in rotation when lightning strike happens. The influence of the rotation to the lightning attachment manner of wind turbine blade is not fully studied. Experimental work has been done in this paper. A 1:30 scale 3MW wind turbine is built. There are 3 side receptors on each blade according to the real wind turbine blade. A rod electrode is used as the high voltage electrode to simulate the downward leader. Both negative and positive 250/25000 mu s standard switching impulses are applied. Different blade tip linear speeds, equal to the real wind turbine, are used to study the influence of the blade rotation to attachment process. The results show that the influence of the rotation can be classified into two types, one is the impact on the location of the striking attachment point, the other is the impact on the discharge channel close to the blade. The influence depends on the polarity of the discharge. Positive discharge is more dangerous to wind turbine blade in rotation.