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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

High Impedance Arc Fault Detection in a Manhole Environment.

Cooke, Thomas Arthur 18 December 2010 (has links) (PDF)
The scope of this thesis was to develop a prototype high-impedance arc detection system that a utility worker could use as an early warning system while working in a manhole environment. As part of this system sensors and algorithms were developed to increase the sensitivity of detecting an arc while ignoring loads that can give false positive signatures for arcing. The latest technology was used to repeat measurements performed in previous research from decades ago that lacked in sampling speed and amplitude resolution. Several types of arcs were produced and analyzed so to establish a library of various waveform and frequency signatures. The system was constructed as a development unit and is currently gathering information in the field. Data being collected will be analyzed so future revisions will give higher confidence levels of arc detection. Other future plans involve designing a more compact and portable unit.
2

Etude des risques d'arc électrique dans les batteries lithium-ion / Electric arc risks study in lithium-ion batteries

Augeard, Amaury 10 November 2015 (has links)
La sûreté de fonctionnement des batteries est un point clé pour la croissance de ce marché et le déploiement de solutions hybrides afin de réduire la consommation d’énergie. L’électrification croissante de ces systèmes ne fait qu’aggraver l’augmentation de l’occurrence de ce problème qui bien que connu depuis longtemps dans le domaine des applications DC ne fait l’objet de recherches intensives que depuis peu comme en témoigne le développement récent des premiers détecteurs d’arc pour l’aviation. L’arc dans les batteries représente aujourd’hui un risque potentiel pour l’intégrité du matériel et des personnes du fait de l’utilisation des batteries au sein d’applications industrielles de fortes puissances. Afin de caractériser ce risque et d’en évaluer la dangerosité, plusieurs bancs d’essais sont réalisés au niveau élément et système afin de reproduire le phénomène d’arc électrique. Les essais réalisés permettent d’extraire les caractéristiques intrinsèques de l’arc. En complément de cette caractérisation, un modèle d’arc permettant d’évaluer les paramètres et d’améliorer la compréhension de ce phénomène est réalisé. Des solutions de limitation, voire de suppression de l’arc issues de cette étude sont proposées. Parmi ces nombreuses solutions, l’utilisation de capteurs optiques, les méthodes numériques pour le traitement des signaux issus de l’arc, la modification de l’architecture batterie ainsi que l’augmentation du niveau de tension lors de l’amorçage de l’arc ouvrent la voie à la conception de systèmes de batteries innovants et plus sûrs en termes de fiabilité, sécurité et de robustesse. Les nombreuses perspectives de recherches proposées permettront également d’améliorer la couverture de ce risque. / The operational security of batteries is a key element in the growth of this market and the deployment of hybrid solutions to reduce energy consumption.The increasing electrification of these systems can only exacerbate the occurrence ratio increase of this problem. Although known for a number of years in the field of DC applications, electric arcs are the subject of intensive research for a short time as shown by the recent development of the first arc sensors for aviation. Electric arcs in batteries currently represent a potential risk to the integrity of the equipment and people because of the use of these batteries in industrial high power applications. To characterize this risk and assess its dangerousness, several test benches were designed at the cell and system level to reproduce the electric arc phenomenon. The tests carried out allow extracting the intrinsic characteristics of the arc. In addition to this characterization, an arc model to evaluate the parameters and improve the understanding of this phenomenon is realized. Limiting mitigation solutions or suppression of the arc resulting from this study are proposed. Among the many solutions, the use of optical sensors, the numerical methods for digital signal processing from the arc, the modification of the architecture as well as the increase of the arc ignition voltage pave the way for the design of innovative and safer batteries systems in terms of reliability, security and robustness. The numerous proposed research perspectives will also improve the coverage of this risk.
3

Vznik a detekce elektrického oblouku v sítích nn / Electric fault arc detection in LV network

Dubský, Martin January 2018 (has links)
This thesis deals with arc detection using AFDD. Here is explained the general theory of electric arc. It also describes the principle of operation of the AFDD device, a specific type of instrument from OEZ s.r.o. and describe the test procedure for this instrument according to the technical standard. In the practical part, selected tests are performed and verified the function of the AFDD device in the event of a disturbance electric arc in the circuit.
4

Series Dc Arc Characterization, Prevention & Detection inAircraft Systems

Bauer, Eric Charles 09 July 2019 (has links)
No description available.

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