Parameters of the Initial Continuous Current of Negative Upward Lightning Measured at the Peissenberg Tower, Germany, From 1992 to 2022

Abstract

In this article, we analyze the parameters of the initial continuous current (ICC) of the negative upward lightning measured at the Peissenberg Tower, Germany, from 1992 to 2022. A total of 54.9% of them were ICC <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Only</sub> -flashes (without significant ICC-pulse), 24.0% of them were ICC <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">RS</sub> -flashes (with subsequent return stroke), 19.6% of them were ICC <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">P</sub> -flashes (with ICC-pulses > 2 kA), and 1.5% of them were ICC <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Bipolar</sub> -flashes (succeeded by a positive current component). The analysis revealed that the ICC <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Only</sub> -flashes were the weakest ones, the ICC <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">P</sub> -flashes were the strongest ones, and the ICC <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">RS</sub> -flashes and the rare ICC <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Bipolar</sub> -flashes were in between. Out of the total of 204 measured ICCs, 16 (7.8%) of them exceeded the charge of 200 C, which represents the highest tolerable level according to the lightning protection standard IEC 62305-1. The strong ICC <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">P</sub> -flashes carried charges up to 454 C, being more than twice of this tolerable level.