Povezovanje ozemljitve ograje z ozemljitvijo objekta

GNAMUŠ, BOŠTJAN (author), Ažbe, Valentin (mentor)

Strela je naravni razelektritveni pojav, ki nas vedno znova osupne. Lahko jo še ne vem, kako občudujemo, a kadar se nam nevarno približa, smo nemočni. To temo sem si izbral zato, ker je strela izredno pogosti dogodek, ki ga je potrebno dobro preučiti. Začetna raziskanja so se začela z Benjaminom Franklinom leta 1752, ki je tudi postavil fizikalno ozadje za tem pojavom. Benjamin Franklin je hitro po začetku raziskovanja izumil tudi prvo napravo za ščitenje proti streli, ki še danes temelji na isti podlagi. Diplomska naloga je sestavljena iz štirih delov. V prvem delu je najprej navedena teoretična podlaga za razumevanje atmosferskih razelektritev oziroma udarcev strel, tako da je bralcu omogočeno dobro razumevanja raziskovalnega dela diplomske naloge. V drugem delu je bilo potrebno teorijo o nastanku strele pripeljati do fizikalnih lastnosti toka strele, ki je glavna veličina, ki povzroči škodo na objektih. Seveda je to le posledica velikih napetosti med zemljo in nevihtnim oblakom, vendar je tok tisti, ki lahko poškoduje nas, objekte ali pa naprave. V tretjem delu sem s pomočjo primerov izračunov in simulacij za namen standardizacije IEEE opisal nekaj primerov, kako se potencial razporedi po okolici, kadar strela udari v obstoječi strelovod ali drevo. Pridobljeni podatki so prispevali velik del k razumevanju strelovodnega sistema. V zadnjem delu naloge sem združil vso pridobljeno razumevanje in napravil sklep, kakšno je po mojem mnenju najboljša možna ozemljitev ograje in na kaj vse moramo biti pri tem pozorni.

• Language: Slovenian
• Keywords: razelektritveni pojav, ščitenje proti streli, atmosferska razelektritev, tok strele, standardizacija, razlika potencialov, ozemljitev ograje
• Work type: Bachelor thesis/paper
• Organization: FE - Faculty of Electrical Engineering
• Year: 2022
• PID: 20.500.12556/RUL-140406
• COBISS.SI-ID: 121522947
• Publication date in RUL: 14.09.2022

GNAMUŠ, BOŠTJAN, 2022, Povezovanje ozemljitve ograje z ozemljitvijo objekta [online]. Bachelor’s thesis. [Accessed 28 March 2025]. Retrieved from: https://repozitorij.uni-lj.si/IzpisGradiva.php?lang=eng&id=140406

Secondary language

• Language: English
• Title: Connecting fence grounding to object grounding

Abstract

Lightning strike is a natural phenomenon, which amazes us again and again when displayed in front of our eyes. We can admire it, but when it comes too close. we can be powerless. That's why I choose this topic, because lightning strike is a frequent event and it is supposed to be well studied. The first lightning strike researches started with Benjamin Franklin in 1752, who also set the physical background behind this admirable phenomenon. He also quickly after his research invented the first device for protection against lightning and it is still the base for the modern lightning protection devices. Thesis is assembled from four parts. The first one contains theoretical basis for understanding of the lightning discharge, so the reader is enabled for easier understanding of the research part of this thesis. In the second part it was importand to connect the theory about lightning discharge to physical properties of the lightning current, which is the main quantity when lightning discharge occurs on objects. Of course lightning current is only a consequence of the high potential difference between clouds and earth surface, but the power of the lightning current is the one causing damage to us, facilities or devices. In the third part of this thesis I used different examples of the calculations made for the purposes of the standardization IEEE, for describing how potential spreads on the surface in the moment when lightning strikes a tree or a lightning protection system. The obtained data contributed a lot to the understanding of lightning protection. In the last part I combined all the information I gained during the writing the thesis and made a conclusion about what I think is the best possible way to ground a fence and what we should pay attention to when we are designing a lightning protection system.

• Keywords: lightning discharge, protection against lightning, lightning current, potential difference, grounding of a fence.