Electrical Insulators
Mostrando 13-21 de 21 artigos, teses e dissertações.
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13. Efeitos da poluição atmosférica (litorânea e industrial) em isoladores da rede elétrica da região metropolitana de Salvador
The performances of eight kinds of insulators from electrical distribution lines in Salvador-BA, Brazil, were evaluated considering the chemical and physical local environmental pollution. The parameters that were chosen as characteristic for the insulators' properties were leakage current and partial electrical discharge. A data storage processing system an
Química Nova. Publicado em: 2008
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14. Blindagem balÃstica de compÃsito polimÃrico contra o vandalismo e proteÃÃo UV para cadeias de isoladores de vidro em linhas de transmissÃo
The aim of this study was to induce the UV absorption of soda-lime silica glasses by gamma irradiation, as well as to select and evaluate the mechanical and electrical properties and also the microstructure of the polycarbonate (PC), with and without heat treatment, and the glass fiber reinforced epoxy composite, to make a prototype for transmission lines co
Publicado em: 2008
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15. Optical detection system of partial discharges on insulator strings of high voltage transmission lines / Sistema de detecÃÃo Ãptica de descargas parciais em cadeias de isoladores de linhas de transmissÃo de alta tensÃo
Leakage current monitoring is frequently used to evaluate the degradation in the insulation capacity of insulator strings of overhead transmission lines, due to pollution. The pollutants accumulation over the surface of the insulators strings, together with humidity, lead to an increase in the current leak over the insulatorâs surface, in turn producing the
Publicado em: 2008
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16. Isolantes de porta com altas constantes dieletricas (High K) para tecnologia MOS / High K gate insulators for MOS technology
High k insulators for the next generation (sub-32 nm CMOS (complementary metaloxide-semiconductor) technology), such as titanium oxide (TiOx), titanium oxynitride (TiOxNy), titanium-aluminum oxynitride (AlxTiwOyNz), titanium-aluminum nitride (AlxTiwNz) and titanium-aluminum oxide (AlxTiwOy), have been obtained by Ti or Ti/Al e-beam evaporation, with addition
Publicado em: 2008
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17. Estudo de um novo compósito madeira-resina poliuretana para o desenvolvimento de um isolador híbrido / Study of a new wood-polyurethane resin composite for the development of a hybrid insulator
This work aims at the study of the application of reforestation wood, of Pinus Taeda species, impregnated with polyurethane resin derived from the castor-oil plant as a new product for the manufacture of hybrid electric insulators. This research possesses a great ecological appeal, as the wood-polyurethane resin composite derived from reforestation wood and
Publicado em: 2007
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18. The effects of fillers on polyurethane resin-based electrical insulators
The increasingly widespread use of polymeric insulators in vehicle distributors and transmission systems has led to an ongoing quest for quality and low costs. This quest has, in turn, resulted in improved performance and cost benefits, brought about by the use of new polymeric and composite resins. Occasionally, however, while some properties are improved,
Materials Research. Publicado em: 2003-06
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19. Desenvolvimento e avaliaÃÃo de um escudo polimÃrico para minimizar a quebra de isoladores de vidro por vandalismo em linhas de transmissÃo
Electrical insulators are largely employed in the hot lines to isolate the electricity conductors from the earth and suppor them at the towers. Nowadays, there are several kinds of isolatores for such application. Particularly, the glass insulators are largely employed in Brazil, and it is known to have a long useful life, able to reach more than 40 years. F
Publicado em: 2003
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20. Estudo teórico de característica elétrica de contato schottky não íntimo metal-isolante amorfo e estrutura metal-isolante-metal / Theoric study of electrical of Schottky contact from metal-insulator-metal and metal-amorphous insulators structures
No presente trabalho foi desenvolvida uma teoria de característica elétrica da estrutura metal-isolante-metal considerando uma camada fina de óxido entre o metal e o isolante, sendo o óxido um outro isolante de banda de energia proibida mais larga. Foi considerada uma distribuição energética uniforme de estados de impurezas à interface óxido-isolant
Publicado em: 1989
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21. Metodo de calculo de isolamento de torres de transmissão de energis eletrica face ao risco desejado para surto de manobra
The cost of an electrical transmission line depends greatly on the cost of its towers, which in turn are priced according to their dimensions and weight. These factors are greatly influenced by the insulation and particulary by the dimensions of the air-gaps. Large air-gaps have lower risks-of-failure when submitted to a given electrical stress than srnaller
Publicado em: 1989