With the rapid development and application of tethered unmanned aerial vehicle (UAV) systems, the lightning strike risk faced by the tethered UAV systems has become a severe issue that cannot be ignored. Compared with traditional UAVs, the presence of the tether cable in tethered UAV systems has brought significant changes to the potential lightning strike risks of them, and the relevant influencing factors on the lightning strike probability have also changed.

This study aims to investigate the lightning strike point distribution of a typical tethered UAV system by combining electrostatic field analysis and numerical simulation. The goal is to present the lightning strike probability of different parts of the tethered UAV system and identify its main influencing factors.

The ANSYS finite element analysis software was used to analyze the electrostatic field distribution around the tethered UAV system under the background electric field of thunderstorm, and the lightning strike points with higher probability on the tethered UAV system were determined. On this basis, a numerical simulation assessment of lightning strikes on a typical tethered UAV system was carried out by employing the dielectric breakdown model and the sub-grid technology. The lightning strike probability distribution on different parts of the tethered UAV system was obtained, and the influence law of different factors on the lightning strike probability was presented.

The results of the numerical simulation show that the lightning strike probability of the tethered UAV system increases approximately linearly with the increase of the tethered height and the volume charge density of thundercloud. When the tethered UAV system is struck by lightning, the lightning strike probability on the end of the rotor arm is the highest, followed by the UAV fuselage, and the lightning strike probability on the tether cable is relatively low.

By combining electrostatic field finite element analysis with large-sample numerical simulation of lightning discharge, the lightning strike probability distribution characteristics of the tethered UAV system and the surrounding ground under different conditions are determined, which can provide an important reference for the direct lightning protection design of the tethered UAV system.