Lightning protection of wind turbines — A comparison of lightning data & IEC 61400-24

IEC 61400-24 dealing with lightning protection of wind turbines was first introduced in 2002. This was initially developed as a technical report. Since then, wind power has been rapidly developing with wind turbine manufacturers developing larger wind turbines which are at an increased risk of lightning strikes. With the move of large wind farms offshore, maintenance of wind turbines also becomes harder owing to the harsh and unpredictable environment. Limiting lightning strike damage on wind turbines becomes even more important. The IEC technical report has recently been developed into a full standard by the committee. The test levels (at which components should be tested) stated in the standard are based on those presented in IEC 62035 - Protection against Lightning. The present paper discusses the relevancy of the test levels in comparison to actual lightning strike data gathered from different wind farms of the world.