25 Results for the search " line":
Interaction Between Grounding Systems and Nearby Lightning for the Calculation of Overvoltages in Overhead Distribution Lines
Description:The aim of the paper is to analyze overvoltages in overhead distribution lines induced by nearby lightning return stroke currents taking into account also the conductive coupling between the lightning... see more current injected into the soil and the line’s grounding system. Experimental results obtained in 2003 at the International Center for Lightning Research and Testing (ICLRT) in Florida have shown that significant currents were coupled with an overhead experimental line through its grounding system by nearby rocket-triggered lightning.
The paper first proposes a conductive coupling model between the lightning current injected into the soil and the nearby line grounding system, then presents the incorporation of such a model into the LIOV-EMTP computer code. The paper finally presents an experimental validation of the proposed models by making reference to results obtained during the above-mentioned triggered-lightning campaign.
Authors: F. Napolitano, M. Paolone, A. Borghetti, C.A. Nucci, F. Rachidi, V.A. Rakov, J. Schoene and M. A. Uman
Tag(s): lightning induced overvoltages, grounding systems, overhead distribution lines, lightning protection.
Protection Systems Against Lightning-Originated Overvoltages in Resonant Grounded Power Distribution Systems
Description:A joint research project between AES Sul, the Federal University of Itajubá and the University of Bologna aims at defining the required protections against lightning-originated overvoltages in a reso... see morenant grounded distribution system in order to achieve the adequate lightning performance level with minimum cost. The paper aims at illustrating the effectiveness of the presence of a surge arrester or spark gap and their protective zone by means of simulations obtained with a computer code for the calculation of lightning induced voltages that takes also into account the steady-state voltage. The results of a statistical analysis for a single multiconductor line are eventually presented and discussed.
Authors: A. Borghetti, F. Napolitano, C.A. Nucci, M.L.B. Martinez, G.P. Lopes, J.I.L. Uchoa
2012 International Conference on Lightning Protection (ICLP), Vienna, Austria
Tag(s): Lightning protection, power distribution networks, induced overvoltages.
Assessment of the Lightning Performance of Compact Overhead Distribution Lines
Description:The assessment of the lightning performance of a compact configuration of MV overhead lines that is expected to be adopted in the near future by an electricity distribution company in a Brazilian regi... see moreon characterized by high keraunic levels is presented. The compact configuration is characterized by the presence of an unenergized wire that has the main function to sustain the spacers of the phase conductors. As the wire could be periodically grounded, the paper analyses its effectiveness in reducing the overvoltages due to indirect lightning. The results are compared with those relevant to a conventional configuration of MV overhead lines now adopted by the same distribution company. The effects of the presence of surge arresters along the line are also analysed.
Authors: F. Napolitano, A. Borghetti, D. Messori, C.A. Nucci, M.L.B. Martinez, G.P. Lopes, J.I.L. Uchoa
CIGRE SC C4 2012 Hakodate Colloquium
Tag(s): Lightning protection, Overhead distribution lines, Induced overvoltages, Electromagnetic transients.
Pseudo Aleatory Volt/Ampere source
Description:Pseudo Aleatory Volt/Ampere source single and three phases devices. Build with Base Line Wander generator. Useful for Spectrum Analysis
nota bene: ts must be a multiple of dt.
Tag(s): Source
Cross_Bonded_Cable
Description:Insulation coordination - 225 kV cross bonded cable - protection of the sheath.
In the configuration a 225 kV cross-bonded cable is connected at both ends to an otherhead line. The sheath is prot... see moreected by star-connected arresters.
The modelling used is adapted for the study of Fast-Front-Overvoltages (see IEC 60071)
A current source, with a CIGRE concave shape (See CIGRE 63 document), representing a lightning stroke has been connected to a tower close to the cable.
The case includes the modelling of the different elements of the configuration (cable, spans, arresters...).
Tag(s):