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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

Diagnostic measurements on a low-pressure inductively coupled Hg-Kr discharge

Whitby, James Andrew January 1996 (has links)
No description available.
2

Estudo do comportamento elétrico de lâmpadas fluorescentes / Study of the electric behavior of fluorescent lamps

Siqueira, Gabriela de Paiva 06 October 2011 (has links)
Orientador: Yaro Burian Junior / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação / Made available in DSpace on 2018-08-18T15:41:19Z (GMT). No. of bitstreams: 1 Siqueira_GabrieladePaiva_M.pdf: 1004897 bytes, checksum: 434e195d542578fc2f9b88f6143f079d (MD5) Previous issue date: 2011 / Resumo: Este trabalho apresenta o estudo do comportamento elétrico de lâmpadas fluorescentes compactas. Ele engloba a análise dos componentes da lâmpada e do circuito do reator, a análise da estabilidade do ponto de funcionamento dessas lâmpadas, o estudo das características estáticas e dinâmicas, criação de modelo matemático, simulações e experimentos. Também é analisado o fenômeno de cintilações em lâmpadas fluorescentes desligadas. Inicialmente foi feita a análise geral das características da lâmpada e dos reatores magnéticos e eletrônicos. Foi feita uma análise comparativa entre os reatores eletrônicos e magnéticos levando-se em consideração as principais características de uso: tamanho, custo, efeito estroboscópico e fator de potência. Em seguida foi estudando o comportamento estático da lâmpada fluorescente. Foi feita a análise da estabilidade do ponto de funcionamento da lâmpada em regime estático levando-se em consideração o circuito externo e a dinâmica do plasma. Verificamos que existe uma boa aproximação para a curva característica estática na região de interesse. Ainda em regime estático observamos que, com corrente constante, existe uma oscilação periódica não senoidal na tensão, sobrepostas à tensão constante, da ordem de até uma dezena de volts e com freqüências da ordem de 10 kHz. O comportamento dinâmico da lâmpada fluorescente foi estudado a partir das equações do circuito externo, da dinâmica da lâmpada e da aproximação da característica estática. Simulações na freqüência de distribuição de energia elétrica (60 Hz) foram comparadas com os resultados obtidos experimentalmente. Simulando também o funcionamento da lâmpada alimentada por tensões senoidais em freqüências mais elevadas verificamos que a tensão e a corrente na lâmpada tendem para curvas senoidais em fase, confirmando que ela tende a funcionar como resistor em altas freqüências. As experiências em alta freqüência confirmaram essa tendência. Também notamos, através da verificação dos circuitos dos reatores de diversas lâmpadas ao longo dos anos, que o filtro de entrada dos reatores eletrônicos das lâmpadas fluorescentes compactas comerciais foi suprimido. Fato que se revelou causador de um evento indesejável dessas lâmpadas: a ocorrência de emissão de lampejos de luz de baixa intensidade e curta duração em intervalos da ordem de 1 minuto por algumas lâmpadas fluorescentes compactas desligadas. Foi analisado o motivo e proposta uma solução para eliminar este fenômeno / Abstract: This work presents a broad study of the electrical behavior of compact fluorescent lamps. It includes an analysis of the lamp components and the circuit of the reactor; an analysis of the stability on the operating point of the lamp; a study of static and dynamic characteristics; a development of a mathematical model; simulations and experiments. It is also analyzed the phenomenon of sparkling in turned off fluorescent lamps. First it was made a general analysis of the characteristics of those lamps with magnetic and electronic reactors. Then it was made a comparative analysis between them considering the main usage characteristics: size, cost, stroboscopic effect and power factor. It was then studied the static behavior of fluorescent lamps. It was made an analysis of the stability on the operation point of the lamp in static regime considering not only the external circuit but also the plasma dynamic. It was shown that there is a good approximation for the static characteristic curve in the region of interest. We also observed that, with a constant current, the voltage has a periodic (but not sinusoidal) oscillation on top of a constant value of voltage. This oscillation of dozens of volts has a frequency of about 10kHz. The dynamic behavior of the fluorescent lamp was studied by using: the equation of the external circuit, the equation of the lamp dynamic and the equation of the approximation of the static characteristic. It was made simulations in the frequency of electric energy distribution (60Hz) and they were compared with the results obtained experimentally. When it was simulated the functioning of the lamp fed by sinusoidal voltage in high frequencies, we saw that both voltage and current in the lamp tend towards sinusoidal curves in phase, confirming that the lamp has a tendency to function as a resistor in high frequencies. The experiences in high frequencies confirmed this trend. We also saw, by looking at reactors circuits over the years, that the entrance filter was suppressed from electronic reactors of commercial compact fluorescent lamps. This fact revealed to be the cause of an undesirable effect of these lamps: the emission of flashes with small intensity and short duration in intervals of about a minute by some fluorescent lamps when they are turned off. It was analyzed the reason and it was proposed a solution to eliminate this phenomenon / Mestrado / Energia Eletrica / Mestre em Engenharia Elétrica
3

A Dimmable High Power Factor Electronic Ballast for Compact Fluorescent Lamps

Lam, John 18 July 2012 (has links)
Incandescent lamps are now being gradually replaced by Compact Fluorescent Lamps (CFLs) as CFLs consume less power to produce the same light output and its lifetime is much longer than that of an incandescent lamp. However, current CFLs have the following drawbacks: (1) the line current drawn from the CFL produce a large amount of unwanted harmonics that results in very poor input power factor; (2) the dimming performance of a CFL with conventional incandescent lamp dimmers is very poor. The performance of the CFL depends on the design of the electronic ballast circuit that is located at the base of each CFL. For a CFL electronic ballast to be practical, its size and cost is of utmost importance. Thus, the main challenge in the design of practical dimmable CFL ballasts is to solve the aforementioned CFL performance issues while minimizing its size and cost. In the first part of this dissertation, two novel high power factor single-stage electronic ballast topologies are proposed to solve the poor power factor issue of the CFLs that are currently on the market. Both proposed circuits have the following advantages: (1) only one switch is required in the power circuit; (2) the switch has both lower current and voltage stress than other conventional circuits; (3) the built-in power factor correction (PFC) circuit allows incandescent phase-cut dimmer to be used for dimming the CFL; (4) the circuit design is simple and it requires less system space compared to other conventional high PF electronic ballast topologies. The second part of this dissertation proposes a new control circuit that enables the lamp to maintain high power factor throughout the majority of the dimming range. In the proposed control scheme, the dimmer phase-cut angle is fed-forward to the control circuit. The controller then determines the proper duty cycle based on the phase-cut angle to facilitate the desired dimming operation. This novel control circuit was first implemented using analog circuitry. After assessing the performance of the analog version of the proposed controller, it was then digitally implemented through the Field Programmable Gate Array (FPGA) technique. The feasibility and performance of both the proposed electronic ballasts and control concept have been verified through theoretical analysis, simulation and experimental results on a 13W 4-pin D/E CFL from Osram Sylvania. / Thesis (Ph.D, Electrical & Computer Engineering) -- Queen's University, 2010-04-30 12:51:59.682
4

A discrete dimming ballast for linear fluorescent lamps

Wang, Haiyan January 2003 (has links)
No description available.
5

Analyzing the potential impact of low-cost compact fluorescent lamps on a rural distribution system in the Tennessee Valley Authority service territory a thesis presented to the faculty of the Graduate School, Tennessee Technological University /

Johns, Gerald D., January 2009 (has links)
Thesis (M.S.)--Tennessee Technological University, 2009. / Title from title page screen (viewed on July 16, 2010). Bibliography: leaves 106-109.
6

Um modelo de gestão para resíduos industriais pós-consumo /

Silveira, Denise Antunes da. January 2004 (has links)
Orientador: Jayme de Oliveira Campos / Banca: Eugênio Foresti / Paulo Milton Barbosa Landim / Título do folheto: O pneu chorão / Sandra Aymone 24 p. / Resumo: Alguns resíduos sólidos domiciliares podem conter substâncias químicas com características tóxicas, como os metais pesados presentes em diversos materiais provenientes de resíduos industriais pós-consumo. Como exemplo, pode-se citar as lâmpadas fluorescentes, as pilhas e as baterias, que, por possuírem metais pesados em suas composições geram um alto grau de toxicidade, bioacumulação e persistência no meio ambiente, causando preocupações ambientais e prejuízos para a saúde humana. Outro resíduo industrial pós-consumo que atualmente causa enorme prejuízo ambiental, se disposto inadequadamente, são os pneus inservíveis: ainda hoje muitas carcaças de pneus inservíveis são depositadas em cursos d'água, voçorocas ou nos terrenos baldios das cidades, fator que gera, além de outros problemas, a proliferação de larvas e mosquitos. Esta pesquisa se propôs a esclarecer qual o destino final fornecido à estes resíduos industriais pós-consumo (pilhas, baterias, lâmpadas fluorescentes e pneus inservíveis) na cidade de Rio Claro/SP. Foi adotada a metodologia de aplicação de questionários em residências previamente selecionadas e em estabelecimentos que comercializam os produtos citados e, de posse dos resultados finais, elaborou-se um modelo de gestão para a correta destinação dos produtos enfocados. / Abstract: Some solid domestic wastes may contain toxic chemicals, as the heavy metals present in several materials deriving from post-consumption industrial wastes. For instance, it can be mentioned the domestic batteries, the fluorescent lamps, which, because of the heavy metals in their composition, produce a high level of toxicity, bio-accumulation and persistence in the environment, causing prejudicial effects to the human health and the environemnt. Another post-consumption industrial waste that currently cause an enormous environmental damage, if disposed inadequately, are the worn out tires: currently, several frame-works of worm out tires are deposited in streams and rivers and erosion sites, that cause, amoung other problems, the proliferation of larvae and mosquitoes. This research purposed to clear what the final destination of the mentioned post-consumption industrial wastes (batteries, fluoescent lamps, worm out tires) in Rio Claro city, São Paulo State, Brazil. The application of questionnaires methodology in previously selected residences and stores which sell the above mentioned products was adopted and, considering the final results, a pattern of management for the correct destination of the reported products was archieved. / Mestre
7

Advanced high-frequency electronic ballasting for gas discharge lamps

Moussaoui, Zaki 01 April 2003 (has links)
No description available.
8

”ÄNTLIGEN!”- En lysrörsarmatur för det egna hemmet / ”FINALLY!”-A fluorescent fixture for the private home.”FINALLY!”-A fluorescent fixture for the private home.

Lindahl, Anton, Sandelin, Samuel January 2010 (has links)
The aim of our study is to ascertain whether a hanging suspension fluorescentlamp for a private home environment is going to be attractive for a largeaudience. We want to open up for new uses of fluorescent lamps as lightsources.The main approach in this work is how to design a fixture with fluorescentlamps as a light source that will meet the requirements and requests of thehome environment could look like. At the same time we want to make a newimpression of how a fluorescent light source.Primarily we used a quantitative method, but this was rejected after a pilotstudy. Instead we used a qualitatively based method in the sense that weconducted a group interview as well as individual interviews.Based on data from the interviews and our preliminary work a prototype wasbuilt. This prototype is a fluorescent fixture equipped with 2x14W T5fluorescent lamps, dimmed separately. The shape can be described as a soft,organic elongated oval. The luminary screen is made of rice paper, which givesa soft and pleasant light transmission. Access to the interior and electronics isprovided via the open ends of the screen, which is concealed by two endcapsules in plastic. The luminary is a hanging suspension via two wires fromthe ceiling, down to a metal bracket with the same curvature as the luminaryscreen. This metal bracket is then attached to the fixture with wires attached tothe interior, which in turn holds the screen.Our main conclusion is that you can create a very attractive light fitting for theprivate home market. In addition, we concluded that in order to achievesufficient data in a quantitative based study you need more time than what ispermitted within the timeframe of our work. We believe more in the idea offirst develop a good and functional prototype and then ask a panel ofprospective customers what they think about it. Their response will thereafterbe worked in to the final product.KeywordsFluorescent Luminary, fluorescent lamps, fluorescent lamps and luminaries,market, rice paper, dimmableAbstractThe aim of our study is to ascertain whether a hanging suspension fluorescentlamp for a private home environment is going to be attractive for a largeaudience. We want to open up for new uses of fluorescent lamps as lightsources.The main approach in this work is how to design a fixture with fluorescentlamps as a light source that will meet the requirements and requests of thehome environment could look like. At the same time we want to make a newimpression of how a fluorescent light source.Primarily we used a quantitative method, but this was rejected after a pilotstudy. Instead we used a qualitatively based method in the sense that weconducted a group interview as well as individual interviews.Based on data from the interviews and our preliminary work a prototype wasbuilt. This prototype is a fluorescent fixture equipped with 2x14W T5fluorescent lamps, dimmed separately. The shape can be described as a soft,organic elongated oval. The luminary screen is made of rice paper, which givesa soft and pleasant light transmission. Access to the interior and electronics isprovided via the open ends of the screen, which is concealed by two endcapsules in plastic. The luminary is a hanging suspension via two wires fromthe ceiling, down to a metal bracket with the same curvature as the luminaryscreen. This metal bracket is then attached to the fixture with wires attached tothe interior, which in turn holds the screen.Our main conclusion is that you can create a very attractive light fitting for theprivate home market. In addition, we concluded that in order to achievesufficient data in a quantitative based study you need more time than what ispermitted within the timeframe of our work. We believe more in the idea offirst develop a good and functional prototype and then ask a panel ofprospective customers what they think about it. Their response will thereafterbe worked in to the final product. Keywords Fluorescent Luminary, fluorescent lamps, fluorescent lamps and luminaries,market, rice paper, dimmable
9

”ÄNTLIGEN!”- En lysrörsarmatur för det egna hemmet / ”FINALLY!”-A fluorescent fixture for the private home.”FINALLY!”-A fluorescent fixture for the private home.

Lindahl, Anton, Sandelin, Samuel January 2010 (has links)
<p>The aim of our study is to ascertain whether a hanging suspension fluorescentlamp for a private home environment is going to be attractive for a largeaudience. We want to open up for new uses of fluorescent lamps as lightsources.The main approach in this work is how to design a fixture with fluorescentlamps as a light source that will meet the requirements and requests of thehome environment could look like. At the same time we want to make a newimpression of how a fluorescent light source.Primarily we used a quantitative method, but this was rejected after a pilotstudy. Instead we used a qualitatively based method in the sense that weconducted a group interview as well as individual interviews.Based on data from the interviews and our preliminary work a prototype wasbuilt. This prototype is a fluorescent fixture equipped with 2x14W T5fluorescent lamps, dimmed separately. The shape can be described as a soft,organic elongated oval. The luminary screen is made of rice paper, which givesa soft and pleasant light transmission. Access to the interior and electronics isprovided via the open ends of the screen, which is concealed by two endcapsules in plastic. The luminary is a hanging suspension via two wires fromthe ceiling, down to a metal bracket with the same curvature as the luminaryscreen. This metal bracket is then attached to the fixture with wires attached tothe interior, which in turn holds the screen.Our main conclusion is that you can create a very attractive light fitting for theprivate home market. In addition, we concluded that in order to achievesufficient data in a quantitative based study you need more time than what ispermitted within the timeframe of our work. We believe more in the idea offirst develop a good and functional prototype and then ask a panel ofprospective customers what they think about it. Their response will thereafterbe worked in to the final product.KeywordsFluorescent Luminary, fluorescent lamps, fluorescent lamps and luminaries,market, rice paper, dimmableAbstractThe aim of our study is to ascertain whether a hanging suspension fluorescentlamp for a private home environment is going to be attractive for a largeaudience. We want to open up for new uses of fluorescent lamps as lightsources.The main approach in this work is how to design a fixture with fluorescentlamps as a light source that will meet the requirements and requests of thehome environment could look like. At the same time we want to make a newimpression of how a fluorescent light source.Primarily we used a quantitative method, but this was rejected after a pilotstudy. Instead we used a qualitatively based method in the sense that weconducted a group interview as well as individual interviews.Based on data from the interviews and our preliminary work a prototype wasbuilt. This prototype is a fluorescent fixture equipped with 2x14W T5fluorescent lamps, dimmed separately. The shape can be described as a soft,organic elongated oval. The luminary screen is made of rice paper, which givesa soft and pleasant light transmission. Access to the interior and electronics isprovided via the open ends of the screen, which is concealed by two endcapsules in plastic. The luminary is a hanging suspension via two wires fromthe ceiling, down to a metal bracket with the same curvature as the luminaryscreen. This metal bracket is then attached to the fixture with wires attached tothe interior, which in turn holds the screen.Our main conclusion is that you can create a very attractive light fitting for theprivate home market. In addition, we concluded that in order to achievesufficient data in a quantitative based study you need more time than what ispermitted within the timeframe of our work. We believe more in the idea offirst develop a good and functional prototype and then ask a panel ofprospective customers what they think about it. Their response will thereafterbe worked in to the final product.</p><p>Keywords</p><p>Fluorescent Luminary, fluorescent lamps, fluorescent lamps and luminaries,market, rice paper, dimmable</p>
10

Energy consumption of manufacturing line with special emphasis on lighting system

Saršon, Bruno January 2011 (has links)
The main focus of this project is to investigate the energy consumption of the manufacturing lines in the car industry and look for the potential methods regarding energy saving. Special emphasis is put on the lighting technologies that can be used in the manufacturing processes. Two lighting technologies are tested in order to see which one has better performance and lower energy consumption. Fluorescent tube and LED tube are compared concerning illuminance, UV irradiance and power consumption. Economic evaluation is also conducted to exam the feasibilities replacing fluorescent tubes with LED tubes. Results of the study show that the LED tubes have much lower energy consumption than fluorescent tubes, produce more direct and „colder“ light, and have much lower UV irradiance. However, the payback period of LED is relatively long at current price situation. Since it is expected that the price of LED tubes will decrease in future, it is reasonable to predict that the LED technology will change the fluorescent one in many applications. The energy consumption has been estimated for two manufacturing lines which use different technologies to produce car underbodies. In order to identify the differences from the energy consumption point of view, some measurements are conducted, such as the consumption of electricity, compressed air, air for ventilation and cooling water. The measured results show a disproportion in the power consumption when the lines are in stand-by mode. This affects the energy consumption per produced unit significantly. The line that has a higher capacity and a lower power consumption in the stand-by mode has a lower energy consumption per produced unit when it is operating with lower production loading. So, in order to improve the energy efficiency, it is necessary that it works at as high volume as possible and to have the stand-by power consumption as low as possible.

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