Monitoring Lightning Activity on a Wind Turbine in Croatia: Observations During Spring and Summer Season

This paper provides an overview of lightning currents measured on a wind turbine in the southern part of Croatia during the summer and spring months in 2023. The wind turbine has been equipped with two Rogowski coils installed at the base of the tower since July 2022. A high-speed camera has been installed since April 2023. In addition, Croatian territory has been covered by a ground-based lightning location system since 2009, and therefore lightning flash data, including amplitude, timing, and polarity, is also available onsite. This paper presents and briefly reviews lightning events by examining current waveforms, high-speed camera frames of the lightning channels and associated luminosity profiles, and lightning location system data. In the considered period, there were 34 lightning flashes. There were 33 upward flashes initiated from the WT blades and only 1 downward flash initiated from the cloud. In terms of polarity, 18 flashes transferred negative charge to the ground, 12 transferred positive charge, and 4 transferred both positive and negative charges (bipolar flashes).