Patent ID: 9709039
Date: 2017-07-18
CPC Classifications: F03D,F05D,Y02E

Claim:
1. A lightning current transfer unit for a wind turbine, the lightning current transfer unit comprising: a first portion configured to be electrically coupled to an electrically conducting portion of a blade of a wind turbine electrically connected to a down conductor of the blade; a second portion configured to be electrically coupled to an electrically conducting portion of a nacelle of the wind turbine connected to a down conductor connected to earth; the first portion and the second portion both being independently movable to maintain electrical coupling to the electrically conducting portion of the blade and nacelle respectively; and a lightning current transfer portion comprising a spark gap formed between a first arm electrically connected to the first portion and a second arm electrically connected to the second portion, the first and second arms being configured to move with movement of their respective first and second portions such that the first and second arms are movable relative to one another, wherein the spark gap has a spark gap distance and the lightning current transfer portion is configured such that the distance is substantially constant during movement of the first portion and/or the second portion and such that lightning current is transferred from the first portion to the second portion.