Search results for " Lightning protection"
showing 5 items of 5 documents
EMI Analysis in Electrical Drives under Lightning Surge Conditions
2012
In this paper, a complete model of a power drive system including the earth electrodes is proposed to evaluate electromagnetic conducted interference due to lightning pulses. Circuit model of a power drive system is joined with a full-wave approach for the simulation of the time behavior of the grounding system. The proposed model enables to predict the electromagnetic conducted interference generated in the power drive system when lightning conditions involve the earth electrodes.
Guidelines and Conceptual Design of the Grounding System of the DTT Experimental Facility
2022
The Divertor Tokamak Test (DTT) is an experimental nuclear fusion reactor currently under construction at the ENEA research center in Frascati and whose first plasma is expected in 2025. The present article shows the conceptual philosophy and the guidelines behind the design of the grounding system of the DTT. The article focuses on the main target of the grounding system and on the main technical standards to refer to for the design.
A Methodology for Protection of Trees Against Lightning Strikes as a Measure to Prevent Fires and Loss of Human Life
2021
Some regions may be characterized by a very low annual lightning ground flash density, and yet lightning strikes seem to have been in those areas the cause of widespread wildfires in forested areas. Due to global climate change, these occurrences seem to be an increasing threat. In this paper, the authors discuss the withstand capability of trees against lightning and introduce the criteria for the deployment of tree lightning protection systems (TLPS) to protect forested areas, where deemed necessary by the tree risk assessment. This work analytically identifies the critical trunk radius of the tree below which the tree may explode in the case of a lightning strike and ignite the surroundi…
Un modello dinamico per la simulazione della ionizzazione di terreni non omogenei in presenza di elettrodi disperdenti elevate correnti impulsive
2008
La caratterizzazione elettromagnetica del comportamento dinamico di elettrodi interrati, disperdenti elevate correnti impulsive, costituisce uno degli aspetti primari nella progettazione di un sistema di protezione dalle fulminazioni atmosferiche (LPS). D’altra parte, elevate correnti impulsive possono causare l’insorgere di fenomeni di ionizzazione del terreno, nelle zone prossime agli elettrodi interrati, nei punti in cui il campo elettrico totale supera il valore critico. Modelli teorici e misure sperimentali correlano l’insorgere di variazioni di conducibilità del terreno in prossimità di elettrodi interrati interessati da elevate correnti impulsive al fenomeno della ionizzazione del te…
On the distribution of lightning current among interconnected grounding systems in medium voltage grids
2018
This paper presents the results of a first investigation on the effects of lightning stroke on medium voltage installations' grounding systems, interconnected with the metal shields of the Medium Voltage (MV) distribution grid cables or with bare buried copper ropes. The study enables us to evaluate the distribution of the lightning current among interconnected ground electrodes in order to estimate if the interconnection, usually created to reduce ground potential rise during a single-line-to-ground fault, can give place to dangerous situations far from the installation hit by the lightning stroke. Four different case studies of direct lightning stroke are presented and discussed: (1) two …