Correlation between recorded CG lightning discharges and shut-downs of selected HV overhead power transmission lines in Poland

Review: Factors Affecting the Performance of Ground Electrodes under High Impulse Currents

“…Loboda and Scuka [6] used cylindrical test cells filled with soils of three different resistivities, giving R DC values of 38.6 Ω, 195.7 Ω and 782.8 Ω. The percentage differ-ence between Z imp and R DC was found to be close for the electrodes with R DC values of 195.7 Ω and 782.8 Ω, and 50% lower for the electrode with a much lower R DC value (38.6 Ω).…”

“…One of the most important parameters in the design of grounding systems is soil resistivity, where R DC changes with moisture content, soil composition, soil grain size, compression, chemical content and temperature. Much work [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18] has been published on the effect of soil resistivity on the percentage difference between Z imp and R DC when ground electrodes are installed under varying soil resistivity and subjected to high impulse currents; however, no conclusive or summarising work can be found based on the published work. This paper summarises the published results, as shown in Figures 1 and 2, from work based on field and laboratory approaches, respectively.…”

“…Though several proposed methods of measurement have been adopted to reduce these inductive effects-particularly in investigations of non-linear test load, such as in a surge arrester [41,42]-so far, no specific measurements have been proposed for the arrangement of impulse tests on ground electrodes to reduce these self-and mutually inductive effects. However, a few studies [6,13,43] have been conducted on the effect of current rise times on the behaviour of ground electrodes. Loboda and Scuka [6] performed tests with three current rise times (2-3 µs, 6-7 µs and 8-12 µs) on six test samples in cylindrical test cells.…”

“…[5], based on the configuration of the test cell, the breakdown voltage was used to calculate the starting gradient. Some studies calculate E c from the breakdown voltage [2,[6][7][8], which may result in E c being higher than when it was measured at the initiation of the second current peak. This, again, leads to inconsistencies in the evaluation of E c .…”

Airport Exposure to Lightning Strike Hazard in the Contiguous United States

“…Considering the correlation between lightning intensity and damage typologies to structures (CENELEC, 2011; Darveniza et al., 2004; Fisher, Hoole, Pirapaharan, Thirukumaran, & Hoole, 2014; Loboda & Lenarczyk, 2014), as well as the high sensitivity of lightning risk assessment to lightning flash density parameters (Farkas, Szedenik, & Kiss, 2013), this study contributes to the field by incorporating a lightning intensity parameter (i.e., peak current measures in kiloamperes) to better characterize lightning hazard and explore the spatial patterns of U.S. airports exposure to lightning strikes.…”