Posez n’importe quelle question sur les cours, conférences, exercices, recherches, actualités, etc. de l’EPFL ou essayez les exemples de questions ci-dessous.
AVERTISSEMENT : Le chatbot Graph n'est pas programmé pour fournir des réponses explicites ou catégoriques à vos questions. Il transforme plutôt vos questions en demandes API qui sont distribuées aux différents services informatiques officiellement administrés par l'EPFL. Son but est uniquement de collecter et de recommander des références pertinentes à des contenus que vous pouvez explorer pour vous aider à répondre à vos questions.
This paper presents an analysis of lightning return strokes to tall structures. The interaction of lightning with a tall structure is modeled using the antenna theory. The finite ground conductivity as well as the buried grounding system of the tall struct ...
We propose in this paper new expressions relating lightning return stroke currents and far radiated electric and magnetic fields, taking into account the presence of an elevated strike object. The derived expressions show that the presence of an elevated s ...
Since 1991, a broadband, high-resolution current measurement system has captured the lightning current derivative at the Toronto CN Tower. In this paper, extensive statistics (1992-2001) of CN Tower lightning current waveform parameters (maximum steepness ...
In this paper, an analysis of electric and magnetic fields radiated by lightning first and subsequent return strokes to tall towers is presented. The contributions of the various components of the fields, namely, static, induction, and radiation for the el ...
The voltages induced by nearby lightning strikes are a major cause of outages in power distribution systems. We compute such voltages taking into account the effects of the dart leaders that precede subsequent return strokes in both natural and rocket-trig ...
In this paper, we propose a method based on genetic algorithms to extract primary lightning return stroke current parameters from currents measured using instrumented towers, including the possibility of contamination by multiple reflections occuring along ...
The presence of an elevated strike object markedly affects both the measured lightning return stroke current and the radiated electromagnetic fields. The MTL and the TCS lightning return stroke models have been extended to take into account the presence of ...
Measurements of return stroke currents on instrumented towers reveal the existence of reflections at the tower bottom and top. In the paper, the effects of the reflections on both measured currents and the original lightning electromagnetic fields are disc ...
Return-stroke lightning models and coupling models permit a fairly good estimation of overvoltages induced by indirect lightning strokes. However, some discrepancies that still exist between measured data and calculations stress the necessity to incorporat ...
Expressions relating far electromagnetic fields and return stroke channel base current have been derived in the literature for various lightning return stroke models. The use of such relations permits the estimation of channel base currents of return strok ...
