Influence of wind turbine blade rotation on the lightning discharge characteristic

Compared with other lightning target on ground, the most notable feature of wind turbine is that the blade will normally be in a state of rotation during lightning strike. In order to study the specialty and mechanism of the influence of blade rotation on triggered lightning ability, the paper conducted some lightning discharge comparison tests under different status of stationary and rotating blade on a typical 1:30 reduced-size 2 MW wind turbine. Designed special arching surface electrode to ensure the same distance between the tip of rotation blades and the arching surface electrode all the times. Applying a negative polarity 250/2500μs standard operating wave on the high voltage electrode. The up-and-down method was adopted for 50% discharge voltage and observed the discharge process. The experimental results showed that under the condition of 1m, breakdown voltage will get higher with the blade rotation speed increase, the wind turbine's blade rotation reduced triggering lightning ability. Analysis showed that the rotation of the blades changes the charge distribution of the blade tip region, which affects the discharge development process. The result gives a reference for lightning protection of wind turbines.