2014 International Conference on Lightning Protection ( ICLP ) , Shanghai , China Experimental Study of Lightning Strike Attachment Characteristics on Wind Turbine Generators

Experiments on lightning strike attachment characteristic of the wind turbine with 40-m-long blades, as simulated by a reduced-size model with a scaled ratio of 1:100, have been carried out. Obtained results show that, for all the concerned arrangements, the blade-tip receptor has the largest attachment probability than the other parts of wind turbine. In the case of simulated downward lightning test, the positive discharge tends to attach to the insulation parts of the blade and nacelle, whereas the negative ones tend to be intercepted by the blade-tip receptor and by the lightning rod. A contrary trend was found in the case of simulated upward lightning test. In the switching impulse voltage (250/2500 μs) test, more discharges attach to the insulation parts of blade than those in the lightning impulse ones (1.2/50 μs). Increase in the receptors will result in decreased attachment probability of the blade surface. The blades with a length of 40 m at least need four pairs of receptors in order not to be damaged by lightning. Keywordsattachment characteristic; blade; lightning; receptor; wind turbine generator.