Dissertations / Theses on the topic 'SF6D'
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Al-Kindi, F. J. "A model for impulse breakdown of SF6̲." Thesis, University of Strathclyde, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382317.
Full textQuenin, Alexandre. "Etude des propriétés diélectriques des mélanges azote-SF6 à faible taux de SF6." Grenoble INPG, 2002. http://www.theses.fr/2002INPG0154.
Full textZhang, Quan. "Modelling of turbulent SF6 switching arcs." Thesis, University of Liverpool, 2014. http://livrepository.liverpool.ac.uk/2013339/.
Full textIjumba, N. M. L. "Non-uniform field breakdown in mixtures of SF6̲ and freon 113." Thesis, University of Strathclyde, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382321.
Full textAshraf, Huma. "Anisotropic etching of silicon using SF6 plasmas." Thesis, Imperial College London, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.404383.
Full textLederle, Christoph. "Isoliervermögen SF6-isolierter Elektrodenanordnungen mit dielektrischer Beschichtung." Düsseldorf VDI-Verl, 2009. http://d-nb.info/992593530/04.
Full textCai, Xiaolei. "Elimination of SF6 from transmission system equipment." Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/elimination-of-sf6-from-transmission-system-equipment(4288ba94-8bcb-4805-94ab-5235fca5b94c).html.
Full textHinterholzer, Thomas. "Der Durchschlag in SF6 unter Einfluss der Raumladungsstabilisierung." [S.l. : s.n.], 2002. http://deposit.ddb.de/cgi-bin/dokserv?idn=966110269.
Full textBrookes, Ricky John. "Exploration of polymer replacements for SF6 in circuit breakers." Thesis, University of Liverpool, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.526839.
Full textHarris, Kevin David James. "Realistically evaluating small scale SFD programmes professionalisation and praxis." Thesis, Southampton Solent University, 2016. http://ssudl.solent.ac.uk/3807/.
Full textPetri, Richard. "Etude de l'influence de la température sur les mécanismes de gravure du tungstène et du silicium en plasma SF6 et SF6/O2 dans un réacteur hélicon." Grenoble 1, 1993. http://www.theses.fr/1993GRE10011.
Full textDuffour, Emmanuel. "Interaction plasma-isolant. Applications au lanceurélectrothermique et à l'interaction SF6-polyéthylène." Phd thesis, Université Blaise Pascal - Clermont-Ferrand II, 2000. http://tel.archives-ouvertes.fr/tel-00011655.
Full textUne étude fondamentale de la dynamique moléculaire, basée sur l'utilisation des méthodes numériques particulières comme les intégrateurs symplétiques et l'exploitation des différents potentiels d'interactions existants (Morse, Lennard-Jones...), a abouti à deux modèles de polymère : le polyéthylène ou PE (CH2)n. Le premier modèle dit simplifié consiste à considérer un groupement CH2 comme un atome fictif de masse molaire 14g, tandis que le second plus complet traite la dynamique de l'atome d'hydrogène au sein de la macromolécule. Ces deux modèles sont utilsés, dans le cadre de ce travail, pour diverses interactions.
Par ailleurs, des mesures expérimentales de perte de masse des matériaux polymères qui interagissent avec un plasma, créé par l'explosion d'un fil de cuivre, sont exposées. Ces résultats sont corrélés par des calculs théoriques de thermodynamique qui montrent une différence de comportement des deux polymères testés : le polyéthylène et le polyoxyméthylène, POM ou Delrin (CH2O)n.
Belhaouari, Jean-Belkheir. "Modélisation de l'extinction d'un arc de SF6 hors d'équilibre thermodynamique local." Phd thesis, Université Paul Sabatier - Toulouse III, 1997. http://tel.archives-ouvertes.fr/tel-00003150.
Full textYoshida, Soh, Hiroki Kojima, Naoki Hayakawa, Fumihiro Endo, and Hitoshi Okubo. "Light Emission Spectrum Depending on Propagation of Partial Discharge in SF6." IEEE, 2008. http://hdl.handle.net/2237/12056.
Full textBennis, Mohamed. "Etude expérimentale de la solubilisation de substances organiques dans SF6 supercritique." Paris 13, 1991. http://www.theses.fr/1991PA132002.
Full textShimmin, D. W. "High power short circuit studies on an SF6 puffer circuit breaker." Thesis, University of Liverpool, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.383473.
Full textRebzani, Nesrine. "Etude des phénomènes électro-thermiques dans l'appareillage haute tension." Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENI056/document.
Full textElectricity is produced by power stations and is transported throughout the electric-power transmission at long distances with high voltage apparatus. The GIS (Gas Insulated Switchgear) is widely used switchgear. The electric insulation is ensured by the gas SF6. Security IEC norms impose temperature rises not to be exceeded during GIS operating. It is important to know and control the electromagnetic and thermal phenomenons which generate temperature rises. The switchgear design could then be faster and more precise, leading to only one successful temperature rise test. Solutions to reduce temperatures could also be found. The temperature rise reduction is crucial as it allow a higher current flowing through the GIS and an increase of its efficiency. The word achieved during this thesis presents an analysis of electro-thermal phenomenons in GIS and, more precisely, in busbars. It leads to the determination of the parameters influencing temperature rises and of the heat transfers proportion which is assessed and discussed. A numerical modelization is carried out to examine the temperature rises induced by the current flow in busbars
Ogiboski, Luciano. "Extensão de ciclo de vida de uma subestação isolada a gás SF6 por meio de um sistema de monitoramento de tempo real." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/3/3143/tde-01082013-161555/.
Full textGas Insulated Substations (GIS) are used by energy companies for over 50 years. Many early substations have been in operation until the present day, without any modification in its original design, and still are operating without problems or indications of fatigue. This can be attributed to its constructive quality along with the insulating material used for this type of equipment, the gas sulfur hexafluoride (SF6). This gas has all the desirable features for maintaining the dielectric of the substation as well as being inert and extremely stable. The nominal lifetime of a GIS substation can be 30 to 50 years, depending on their characteristics or manufacturer\'s recommendation. The proximity, or even exceeding, the lifetime generates concern to companies holding these old equipment as regards the operation of the substation safely. Another important aspect is related to gas leakages into the atmosphere because SF6 is among the most damaging elements to the greenhouse effect. Therefore, this work presents the development of a system for monitoring leakage and also indicative parameters of SF6 gas at an old GIS. The main objective was to develop a system with historical data to conduct studies about the behavior of the gas. The substation used for this work had no online monitoring system. Thus, it was developed a real-time system for collecting data of gas density and dew point in the compartments of the substation. The data collection system was installed in three bays of the substation. Sensors were installed to measure these two quantities, and also low cost data acquisition modules which communicate via standard and open protocols. In long term, with the system, there should be a reduction of gas leakages with the possibility of online inspections of the gas. May be assigned as a result the reduction of costs, since the historical data with good indicative allows extending the time for preventative maintenance. As additional result of this work, it is expected that the monitoring of leakage become more efficient and faster, thus contributing to the current environmental expectations.
Yamada, T., T. Ishida, N. Hayakawa, and H. Okubo. "Partial discharge and breakdown mechanisms in ultra-dilute SF6 /N2 gas mixtures." IEEE, 2001. http://hdl.handle.net/2237/6754.
Full textTakahashi, Toshihiro, Tatsuji Yamada, Naoki Hayakawa, and Hitoshi Okubo. "Space charge behavior in SF6 gas and sequential generation of PD pulses." IEEE, 2000. http://hdl.handle.net/2237/6757.
Full textTabke, Thorsten [Verfasser]. "Entwicklung und Anwendung eines typunabhängigen, minimalinvasiven Zustandsbewertungsverfahrens für SF6-Hochspannungsschaltanlagen / Thorsten Tabke." Wuppertal : Universitätsbibliothek Wuppertal, 2017. http://d-nb.info/1136873120/34.
Full textLüders, Carsten. "Vergleich von Strahlungs- und Turbulenzmodellen zur Modellierung von Lichtbögen in SF6-Selbstblasleistungsschaltern." [S.l.] : [s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=978755030.
Full textCastellano, Rémy. "Etude de la régulation transcriptionnelle des gènes TNF-SF6 et TNF-SF14." Aix-Marseille 2, 2003. http://www.theses.fr/2003AIX20656.
Full textConstantin, Florin-Lucian. "Franges de Ramsey à deux photons à très haute résolution de SF6." Paris 13, 2000. http://www.theses.fr/2000PA132028.
Full textBelkacem, Amrane Abdelkrim. "Défauts induits dans le silicium par la gravure en plasma de SF6." Grenoble 1, 1991. http://www.theses.fr/1991GRE10003.
Full textVianna, Elaine Aparecida de Lima. "Priorização da manutenção em subestações com foco na confiabilidade e na remuneração da função transmissão." Universidade Federal de Santa Maria, 2016. http://repositorio.ufsm.br/handle/1/12913.
Full textAs empresas transmissoras de energia, do setor elétrico brasileiro, são remuneradas pelas instalações disponibilizadas para o Sistema Interligado Nacional – SIN. Os diversos equipamentos do sistema de transmissão estão sujeitos à ocorrência de defeitos, os quais podem redundar em falhas e podem resultar em indisponibilidades e/ou restrições operativas. Estas ocorrências provocam a aplicação de uma penalização denominada Parcela Variável, que consiste em um desconto no valor da remuneração. Esta tese visa apoiar o planejamento da manutenção, com o objetivo de reduzir as Parcelas Variáveis e o impacto financeiro negativo, causado por esta penalização, por meio de uma nova metodologia para definir uma escala de prioridade para as ações de manutenções nas subestações, baseada no desenvolvimento de um Índice Composto de Risco (ICR) associado a cada equipamento. São desenvolvidos dois índices auxiliares: Condição Básica (CB) e Condição Operativa (CO), os quais representam as características físicas e funcionais do equipamento, que podem comprometer seu desempenho e contribuir para a ocorrência de falhas. Esta avaliação é realizada com o uso de um Índice de Capacidade Técnica (ICT), que avalia o quanto o equipamento foi afetado pelo desgaste, na avaliação da Condição Básica, e da classificação dos defeitos do equipamento em níveis de severidade, na avaliação da Condição Operativa. Dois Sistemas de Inferência Difusa do tipo Mandani, em um arranjo em cascata, são utilizados, o primeiro na definição da CB, e o segundo para obtenção do ICR que indica a prioridade de manutenção, o qual pode ser utilizado no planejamento das ações de manutenção. Esta metodologia é verificada por meio da avaliação do ICR de Disjuntores a Gás SF6, e sua escala de prioridade para o planejamento de manutenção. O procedimento para avaliação da confiabilidade dos Disjuntores a Gás SF6 é avaliado por meio de uma comparação com uma abordagem estatística, com o uso de dados reais coletados dos registros dos equipamentos instalados no Sistema de Transmissão da Eletrobras Eletronorte, em Rondônia, Região Amazônica do Brasil.
Dal, Bó Sílvia. "Avaliação da atividade antinociceptiva da subfração 63 (SF63) obtida a partir das cascas da Croton Celtidifolius (Euphorbiaceae)." Florianópolis, SC, 2004. http://repositorio.ufsc.br/xmlui/handle/123456789/87159.
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A [SF63], obtida das cascas da [Croton Celtidifolius] administrada por via intraperitoneal, provocou antinocicepção quando avaliada nos modelos de contorção abdominal induzida pelo [Ácido acético], no teste da nocicepção induzida pela [Formalina], no teste da [Capsaicina], no teste [Glutamato], no teste da [Retirada da cauda] e no modelo da [Placa quente], em doses que não promoveram reações inespecíficas, como sedação e relaxamento muscular, avaliadas pelo teste do [Rota-rod]. Também foi observado que a [SF63] administrada por via oral apresenta atividade antinociceptiva, quando avaliada no teste da nocicepção induzida pela formalina. Os resultados sugerem que a [SF63]
Mansour, D. A., H. Kojima, N. Hayakawa, F. Endo, and H. Okubo. "Partial Discharge Characteristics for Small Gap of Electrode/Epoxy Interface in SF6 Gas." IEEE, 2008. http://hdl.handle.net/2237/12127.
Full textWember, Martin [Verfasser]. "Untersuchung und Bewertung von TE-belastetem SF6 unter Anwendung der Ionenbeweglichkeitsspektrometrie / Martin Wember." Aachen : Shaker, 2007. http://d-nb.info/1164340190/34.
Full textFaye, Mbaye. "Signature infrarouge et modélisation pour la télédétection de deux gaz : SF6 et RuO4." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLS182.
Full textThis work is a contribution to the spectroscopic study of two gases of anthropogenic origin for which the modeling of the infrared signature may allow a quantification in releases in the atmosphere. Sulfur hexafluoride (SF₆) is mainly rejected by the electrical industry, which uses it as a gaseous insulator and its concentration increases rapidly in the atmosphere (of the order of 7 per cent per year). It is a potent greenhouse gas listed in the Kyoto Protocol because its intense absorption around 10 μm issituated in a window of atmospheric transparency and its lifetime in the upper atmosphere (approximately 3200 years) confers an exceptionally high radiative transfer coefficient (Global WarmingPotential, or GWP equal to 23900 times that of carbon dioxide,CO2). The detection and quantification of this gas by its infrared signature via satellite measurements requires a very accurate modeling of the absorption spectra, incompletely known. For SF₆,in particular because of the fact that this heavy molecule presents a large number of vibrational levels of low energy, there exist hotbands in the region of atmospheric absorption around its most intense fundamental absorption (v₃); these involve excited states little or not characterized. Thus, at ambient temperature, only 32% of the molecules are located in the vibrational ground state. Current databases contain only data for the fundamental vibrationband. To compensate for this lack, it is therefore necessary toobserve a number of transitions from the ground state to the excited levels of low energy used corresponding to initial states of the hot bands and to acquire data for modeling also levels with two quanta of vibration constituting the upper levels of arrival of thes ehot bands.This work is a contribution to the spectroscopic study of two gases of anthropogenic origin for which the modeling of the infrared signature may allow a quantification in releases in the atmosphere.Sulfur hexafluoride (SF₆) is mainly rejected by the electricalindustry, which uses it as a gaseous insulator and its concentration increases rapidly in the atmosphere (of the order of 7 per cent peryear). It is a potent greenhouse gas listed in the Kyoto Protocolbecause its intense absorption around 10 μm is situated in awindow of atmospheric transparency and its lifetime in the upper atmosphere (approximately 3200 years) confers an exceptionally high radiative transfer coefficient (Global Warming Potential, orGWP equal to 23900 times that of carbon dioxide, CO2). The detection and quantification of this gas by its infrared signature via satellite measurements requires a very accurate modeling of theabsorption spectra, incompletely known. For SF6, in particular because of the fact that this heavy molecule presents a largenumber of vibrational levels of low energy, there exist hot bands in the region of atmospheric absorption around its most intensefundamental absorption (v3); these involve excited states little or not characterized. Thus, at ambient temperature, only 32 % of themolecules are located in the vibrational ground state. Current databases contain only data for the fundamental vibration band. Tocompensate for this lack, it is therefore necessary to observe a number of transitions from the ground state to the excited levels oflow energy used corresponding to initial states of the hot bands andto acquire data for modeling also levels with two quanta ofvibration constituting the upper levels of arrival of these hot bands
Caliap, Lucian. "Etude de l'optimisation des isolants d'un point de vue diélectrique pour les contraintes du GIS." Phd thesis, Université de Grenoble, 2010. http://tel.archives-ouvertes.fr/tel-00585494.
Full textVijayaraghavan, Vishnu Karthik. "Methodology to quantify leaks in aerosol sampling system components." Thesis, Texas A&M University, 2003. http://hdl.handle.net/1969.1/1195.
Full textSmith, Jason. "A Sensor Fault Detection Simulation Tool." Miami University / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=miami1193282225.
Full textMansour, D. A., T. Okusu, K. Nishizawa, H. Kojima, N. Hayakawa, F. Endo, and H. Okubo. "Comparison of Partial Discharge Characteristics for Different Defect Types in SF6 Gas Insulation System." IEEE, 2008. http://hdl.handle.net/2237/12057.
Full textQiu, Xiang Qun. "Impulse breakdown characteristics of SF6 and its mixtures in highly non-uniform field gaps." Thesis, University of Strathclyde, 1998. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=21398.
Full textLüders, Carsten [Verfasser]. "Vergleich von Strahlungs- und Turbulenzmodellen zur Modellierung von Lichtbögen in SF6-Selbstblasleistungsschaltern / Carsten Lüders." Aachen : Shaker, 2005. http://d-nb.info/1186587458/34.
Full textLewis, Elfed. "The thermal properties of an SF6 circuit breaker arc during the current zero period." Thesis, University of Liverpool, 1987. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328394.
Full textLiu, J. "Modelling and simulation of air and SF6 switching arcs in high voltage circuit breakers." Thesis, University of Liverpool, 2016. http://livrepository.liverpool.ac.uk/3003675/.
Full textPaulo, Assis Rogério Gomes da Silva. "Diagnóstico de descargas parciais em subestações isoladas a gás SF6 utilizando redes neurais artificiais." Florianópolis, SC, 2006. http://repositorio.ufsc.br/xmlui/handle/123456789/88736.
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O presente trabalho de dissertação aborda o desenvolvimento de uma ferramenta computacional para o diagnóstico de Descargas Parciais (DP) que ocorrem em Subestações Isoladas à Gás (GIS), em especial ao gás hexafluoreto de enxofre (SF6). Esta ferramenta computacional é baseada nas Redes Neurais Artificiais (RNA), com arquitetura do tipo Multi-Camadas (MLP). O objetivo da ferramenta é fornecer a causa para a ocorrência da Descarga Parcial que é capturada pelo sistema de monitoramento através da emissão de altíssimas freqüências (UHF), dando suporte ao operador para melhores procedimentos em relação à GIS. Para a validação da ferramenta foram utilizados dados gerados a partir do catálogo do sistema de monitoramento instalado na SE Machadinho, pertencente à ELETROSUL. Esse diagnóstico é de grande valia para a manutenção preditiva de uma GIS, pois indica a atividade da DP que dependendo da intensidade e das características destas descargas degradam as características de isolação elétrica do gás SF6. Assim, a equipe de manutenção responsável pela GIS, com a utilização das informações deste diagnóstico, pode atuar de forma mais eficaz nesta subestação. This master#s thesis research results in the development of a computational tool for Partial Discharge (PD) diagnosis taking place at Gas Insulated Substation (GIS), especially with sulphur hexafluoride (SF6). This computational tool is based on an Artificial Neural Network (ANN), with a Multi-Layer Perceptron (MLP) architecture. The target of this tool is to give the cause of occurrence of Partial Discharge captured by system monitoring through emission of ultra high frequency (UHF) signals, giving support to the operator for better procedures about GIS. The tool is validated with data generated from the catalog of a monitoring system installed at Machadinho Substation, owned by the Transmission Company of Electric Energy ELETROSUL. This diagnostic is of great value for GIS preventive maintenance because of given PD activity. Depending on the discharge intensity and characteristic it can destroy the electric isolation of the SF6 gas. With this diagnostic, the responsible maintenance team can work more effectively at this substation.
Robert, Thomas. "Etude d'un arc de disjoncteur à SF6 : modèle physique et intéraction avec le circuit." Toulouse 3, 1992. http://www.theses.fr/1992TOU30021.
Full textBelmadani, Bachir. "Etude de la décomposition de l'hexafluorure de soufre (SF6) dans un arc de puissance." Toulouse 3, 1989. http://www.theses.fr/1989TOU30173.
Full textWang, Weizong. "Investigation of the dynamic characteristics and decaying behaviour of SF6 Arcs in switching applications." Thesis, University of Liverpool, 2013. http://livrepository.liverpool.ac.uk/12033/.
Full textFlores, Ramírez Alejandro Tomás. "Reemplazo de Subestaciones Convencionales Aisladas en Aire por Tecnología Gis (SF6). Análisis Técnico - Económico." Tesis, Universidad de Chile, 2010. http://www.repositorio.uchile.cl/handle/2250/103759.
Full textEl propósito de esta memoria es analizar los aspectos más relevantes relacionados con el reemplazo de subestaciones convencionales con aislamiento en aire por subestaciones con aislamiento en gas hexafluoruro de azufre (SF6). Se analizan distintas alternativas de equipamiento y esquema de suministro para los diferentes tipos de subestaciones, para las configuraciones de aislamiento en aire y aislamiento en SF6. En términos generales, la selección del reemplazo de una subestación convencional por una subestación con aislamiento en gas SF6, responde a las ventajas comparativas relacionadas con un mejor aprovechamiento del espacio, menor intervención al equipamiento debido a mantenimiento, flexibilidad en la operación, mayores niveles de confiabilidad, estandarización a máxima altitud de operación, menor accidentalidad y mayor disponibilidad del terreno, entre otros. En la actualidad, se observa una masificación en el uso de subestaciones con aislamiento en gas SF6, principalmente por la fuerte reducción en los costos de fabricación debido a su producción en serie. Con ello, están desplazando en los estudios de factibilidad a las subestaciones tradicionales con aislamiento en aire, particularmente en instalaciones de alta tensión (220 kV) ubicadas sobre los 1000 m.s.n.m., incidiendo en la toma de decisiones de las grandes empresas de minería y en las empresas de transmisión de energía eléctrica. Se realizaron las valorizaciones de los presupuestos para cada solución (GIS y AIS) en su vida útil, resultando interesante la utilización de equipamiento GIS para las subestaciones de alta tensión tanto en S/E O’Higgins como las Estaciones de Bombeo Nº 2, 3 y 4, principalmente debido a la estandarización de este tipo de equipamiento en las subestaciones eléctricas involucradas en el proyecto, las cuales se ubican hasta 2.400 m.s.n.m.. A esta valorización se debe adicionar como elemento de toma de decisión en la selección del equipamiento, el incremento en la robustez de operación y el mínimo mantenimiento que éstas tienen, reduciendo la necesidad de personal de operaciones y mantenimiento para este objeto, otorgando una gran flexibilidad operacional.
Duluard, Corinne. "Etude de nouvelles voies de passivation non polymérisante pour la gravure profonde du silicium." Phd thesis, Université d'Orléans, 2009. http://tel.archives-ouvertes.fr/tel-00413276.
Full textBorge, Egil. "Modélisation de la cinétique chimique d'un plasma d'arc d'hexafluorure de soufre (SF6) en présence d'impuretés." Toulouse 3, 1995. http://www.theses.fr/1995TOU30184.
Full textLagarde, Frédérique. "Décomposition de l'hexafluorure de soufre (SF6) sous l'effet de décharges couronne influence du matériau d'électrode." Toulouse 3, 1992. http://www.theses.fr/1992TOU30032.
Full textSette, Chaman. "Contribution a l'etude du phenomene de claquage de l'hexafluorure de soufre (sf6) sous haute pression." Toulouse 3, 1987. http://www.theses.fr/1987TOU30163.
Full textRandrianandraina, Hery Zo. "Améliorations des méthodes de calcul du transfert radiatif dans des plasmas thermiques : application au SF6." Toulouse 3, 2011. http://thesesups.ups-tlse.fr/1331/.
Full textBecause of a strong spectral and geometric dependence, the consideration of the radiation and the radiative transfer in the numerical models is done through approximate methods. To validate their use and to bring any improvement, we have compared these methods with the "exact" calculation. In this work, we have carried out a detailed description of the spectrum of SF6 plasmas with about 300000 points on frequency. From this description, we have calculated the divergence of the radiative flux either from the net emission coefficient (NEC) based on a geometric simplification of the plasma, or from the mean absorption coefficients (MAC) calculated after a division of the spectrum into 7 intervals in which we have assumed a constant radiation for each of them, or from an exact calculation corresponding to a direct solution of the radiative transfer equation. We have also calculated the radiative flux from the two last methods since the net emission coefficient is not adapted to estimate this property. The different steps of the work are presented and highlight the influence of several parameters such as the number of points used to discretize the spectrum, the discrepancies observed when we use the escape factor to estimate the emission or the absorption of the lines, the influence of the lines overlapping, the integration of the lines' profiles, the number of directions to consider in order to estimate correctly the divergence of the radiative flux. . . For the mean absorption coefficients, three definitions have been tested : the Planck mean, the Rosseland mean and the classical mean. All calculations have been done for simplified configurations (1D, 2D and 3D) assuming a cylindrical plasma for which the temperature profile varies only with the radius. A great part of this work deals with the comparison between the results obtained from the exact resolution with the results deduced from the other approaches in order to validate the use and the accuracy of the different methods. The results' analysis leads us to redefine new spectral intervals and new mean functions as the combination of the Planck mean and the classical mean. This study have been performed for SF6 plasmas used in high voltage circuit breakers but it could equally be generalized for any thermal plasma in local thermodynamic equilibrium
Okubo, Hitoshi, Diaa-Eldin A. Mansour, Hiroki Kojima, Naoki Hayakawa, and Fumihiro Endo. "Influence of accumulated surface charges on partial discharge activity at micro gap delamination in epoxy GIS spacer." IEEE, 2009. http://hdl.handle.net/2237/13942.
Full textDiaz, Joseph. "Etude de la décomposition de l'héxafluorure de souffre (SF6) et de mélanges héxafluorure de soufre-azote contenant 5% ou 10% de SF6 soumis en présence de divers additifs, à des décharges couronne ou à des claquages." Toulouse 3, 2002. http://www.theses.fr/2002TOU30047.
Full textThe present work deals with the chemical composition of SF6-N2 mixtures containing 5% or 10% of SF6 after being submitted, with a point-plane geometry, to dc negative or 50Hz ac corona discharges (P=400kPa) or sparks generated by discharging a capacitor (P=100kPa; 3. 59J per spark). It was studied in the presence or absence of different additives : H2O and/or O2 for corona discharges and H2O, O2, methane (CH4), ethane (C2H4), octofluoropropane (C3F8), carbon monoxide (CO), carbon dioxide (CO2) or even solid organic insulators like polyethylene [CH2]n, polypropylene [C3H6]n or Teflon [C2F4]n for sparks. The chemical composition of the mixtures was then compared to those of undiluted SF6 submitted to the same types of stress, at the same pressure, in the presence or absence of the same additives. .