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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.
31

Three Dimensional Passive Integrated Electronic Ballast for Low Wattage HID Lamps

Jiang, Yan 03 April 2009 (has links)
Around 19% of global power consumption and around 3% of global oil demand is attributable to lighting. After the first incandescent lamp was invented in 1879, more and more energy efficient lighting devices, such as gas discharge lamps, and light-emitting diodes (LED), have been developed during the last century. It is estimated that over 38% of future global lighting energy demand could be avoided by the use of more efficient lamps and ballasts [1]. High intensity discharge (HID) lamps, one category of gas discharge lamp, have been widely used in both commercial and residential lighting applications due to their merits of high efficacy, long life, compact size and good color rendition [2-4]. However, HID lamps require a well-designed ballast to stabilize the negative VI characteristics. A so-called ignitor is also needed to provide high voltage to initiate the gas discharge. Stringent input harmonic current limits, such as the IEC 61000-3-2 Class C standard, are set for lighting applications. It is well-known that high-frequency electronic ballasts can greatly save energy, improve lamp performance, and reduce the ballast size and weight compared with the conventional magnetic ballast. However, a unique phenomenon called acoustic resonance could occur in HID lamps under high-frequency operation. A low-frequency square wave current driving scheme has proved to be the only effective method to avoid acoustic resonance in HID lamps. A typical electronic HID ballast consist of three stages: power factor correction (PFC), DC/DC power regulation and low-frequency DC/AC inverter. The ignitor is usually integrated in the inverter stage. The three-stage structure results in a large size and high cost, which unfortunately offsets the merit of the HID lamp, especially in low-wattage applications. In order to make HID lamps more attractive in low-wattage and indoor applications, it is critical to reduce the size, weight and cost of HID ballasts. This dissertation is aimed at developing a compact HID with an ultra-compact ballast installed inside the lamp fixture. It is a similar concept to the compact fluorescent lamp (CFL), but it is much more challenging than the CFL. Two steps are explored to achieve high power density of the HID ballast. The first step is to improve the system structure and circuit topology. Instead of a three-stage structure, a two-stage structure is proposed, which consists of a single-stage power factor correction (SSPFC) AC/DC front-end and an unregulated DC/AC inverter/ignitor stage. An SSPFC AC/DC converter is proposed as the front-end. A DCM non-isolated flyback PFC semi-stage and a DCM buck-boost DC/DC semi-stage share the semiconductor switch, driver and PWM controller, so that the component count and cost can be reduced. The proposed SSPFC AC/DC front-end converter can achieve a high power factor, low THD, low bulk capacitor voltage, and the desired power regulation with a simple control circuit. Because the number of high-frequency switches is reduced compared to that of state-of-the-art two-stage HID ballast topologies, the switching frequency can be increased without sacrificing high efficiency, so the passive component size can be reduced. The power density of the whole ballast is increased using this two-stage structure. It results in a 2.5 times power density (6 W/in3) improvement compared to the commercial product (2.4 W/in3). The power density of the converter in discrete fashion usually suffers as a result of poor three-dimensional (3D) volume utilization due to a large component count and the different form factor of different components. In the second step, integration and packaging technologies are explored to further increase the power density. A 3D passive integrated HID ballast is proposed in this dissertation. All power passive components are designed in planar shape with a uniform form factor to fully utilize the three-dimensional space. In addition, electromagnetic integration technologies are applied to achieve structural, functional and processing integration to reduce component volume and labor cost. System partitioning, integration and packaging strategies, and implementation of major power passive integration, including an integrated EMI filter, and an integrated ignitor, will be discussed in the dissertation. The proposed integrated ballast is projected to double the power density of the discrete implementation. By installing the HID ballast inside the lamp fixture, the ambient temperature for the ballast will be much higher than the conventional separately installed ballast, and combined with a reduced size, the thermal condition for the integrated ballast will be much more severe. A thermal simulation model of the integrated ballast is built in the IDEAS simulation tool, and appropriate thermal management methods are investigated using the IDEAS simulation model. Experimental verification of various thermal management methods is provided. Based on the thermal management study, a new integrated ballast with improved thermal design is proposed. / Ph. D.
32

Single-stage high-power-factor electronic ballasts with buck-boost topology for fluorescent lamps

Cheng, Hung-Liang 19 June 2001 (has links)
Three novel single-stage electronic ballasts with the advantages of high-power-factor, low current harmonic, high efficiency, and low cost are proposed for rapid-start fluorescent lamps. Included are (1) single-stage high-power-factor electronic ballast with asymmetrical topology, (2) single-stage high- power-factor electronic ballast with symmetrical topology, and (3) single-stage single-switch high-power-factor electronic ballast. The circuit configurations are obtained by integrating the buck-boost power-factor-correction converter into the Class D or the Class E resonant inverter. With simple circuit configuration and less component count, desired circuit performances of high-power-factor and high efficiency are realized. The control methods of pulse-width-modulation (PWM) with asymmetrical and symmetrical approaches are utilized for the three presented ballasts. The buck-boost conversion stage is operated at discontinuous current mode (DCM) to achieve nearly unity power factor at a fixed switching frequency. With carefully designed circuit parameters, the power switches can exhibit either zero-voltage switching-on (ZVS) or zero-current switching-on (ZCS). As a result, high circuit efficiency can be ensured. Design equations are derived and computer analyses are performed based on the lamp¡¦s equivalent resistance model and fundamental approximation. Accordingly, design guidelines for determining circuit parameters are provided. Prototypes of the three proposed circuits designed for a T8-36W lamp, two series-connected T9-40W lamps and a PL-27W lamp are built and tested to verify the computer simulations and analytical predictions.
33

Consecutive Orthogonal Arrays on Design of Power Electronic Circuits

Yen, Hau-Chen 16 January 2003 (has links)
An approach with ¡§consecutive orthogonal arrays (COA)¡¨ is proposed for solving the problems in designing power electronic circuits. This approach is conceptually based on the orthogonal array method, which has been successfully implemented in quality engineering. The circuit parameters to be determined are assigned as the controlled variables of the orthogonal arrays. Incorporating with the inferential rules, the average effects of each control variable levels are used as the indices to determine the control variable levels of the subsequent orthogonal array. By manipulating on COA, circuit parameters with the desired circuit performances can be found from an effectively reduced number of numerical calculations or experimental tests. In this dissertation, the method with COA is implemented on solving four problems often encountered in the design of power electronic circuits. The first problem one has to deal with is to find a combination with the best performance from a great number of analyzed results. The illustrative example is the design of LC passive filters. Using COA method, the desired component values of the filter can be effectively and efficiently found with far fewer calculations. The second design problem arises from the non-linearity of circuit. An experienced engineer may be able to figure out circuit parameters with satisfactory performance based on their pre-knowledge on the circuit. Nevertheless, they are always questioned whether a better choice can be made. The typical case is the self-excited resonant electronic ballast with the non-linear characteristics of the saturated transformer and the power transistor storage-time. In this case, the average effects of COA obtained from experimental tests are used as the observational indexes to search a combination of circuit parameters for the desired lamp power. The third problem is that circuit functions are mutually exclusive. The designers are greatly perplexed to decide the circuit parameters, with which all functions should be met at the same time. The method with COA is applied to design a filter circuit to achieve the goals of low EMI noise and high power factor simultaneously. Finally, one has to cope with the effects of the uncontrolled variables, such as: ambient temperature, divergence among different manufacturers, and used hours. By applying COA with inferential rules, electronic ballasts can be robustly designed to operate fluorescent lamps at satisfied performance under the influence of these uncontrolled variables.
34

Desenvolvimento de metodologia do projeto do reator eletrônico auto-oscilante com entrada universal / Development of methodology of self-oscillating electronic ballast design with universal input

Lopes, Juliano de Pelegrini 14 January 2010 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / This work presents the design and analysis of an electronic system with universal input to supply a fluorescent lamp. The system includes a self-oscillating electronic ballast and an additional circuit which allows keeping the nominal lamp power although a variation of the input voltage. The electronic ballast design comprises some steps: resonant filter design, self-oscillating gate driver design, additional circuit design and stability test. The electronic ballast is represented as a nonlinear control system in order to achieve a feasible design methodology. Moreover, the system must be analyzed considering the describing function method and the extended Nyquist stability criterion. The proposed electronic ballast must maintain the main characteristics of the traditional self-oscillating electronic ballast. Besides that, the additional circuit has a small number of components and it allows the input voltage full range with automatic selection of the switching frequency. The design, simulation and experimental results of the prototype are presented. / Este trabalho apresenta a análise e o projeto de um sistema eletrônico com entrada universal para alimentação de lâmpadas fluorescentes. O sistema é composto por um reator eletrônico auto-oscilante com um circuito adicional, que permite manter a potência da lâmpada no valor nominal independente da tensão de alimentação. O projeto do reator eletrônico é dividido em etapas, que compreendem o projeto do filtro ressonante, do comando auto-oscilante, do circuito adicional e a análise da oscilação auto-sustentada. Para viabilizar uma metodologia de projeto adequada, o reator eletrônico é representado como um sistema de controle. Para análise e projeto são utilizados a função descritiva e o critério de estabilidade estendido de Nyquist. O reator eletrônico mantém as principais características do reator eletrônico auto-oscilante tradicional. Além disso, o circuito adicional possui um número reduzido de componentes, o que permite empregar o reator eletrônico em qualquer rede de alimentação monofásica sem a necessidade de ajuste manual para escolha da tensão de alimentação. São apresentados resultados de simulação e experimentais do protótipo implementado.
35

Innovative solutions for acoustic resonance characterization in metal halide lamps

Lei, Fang 24 January 2018 (has links) (PDF)
Metal halide lamp is one kind of the most compact high-performance light sources. Because of their good color rendering index and high luminous efficacy, these lamps are often preferred in locations where color and efficacy are important, such as supermarkets, gymnasiums, ice rinks and sporting arenas. Unfortunately, acoustic resonance phenomenon occurs in metal halide lamps and causes light flicker, lamp arc bending and rotation, lamp extinction and in the worst case, arc tube explosion, when the lamps are operated in high-frequency bands. This thesis takes place in the context of developing electronic ballasts with robust acoustic resonance detection and avoidance mechanisms. To this end, several envelope detection methods such as the multiplier circuit, rectifier circuit, and lock-in amplifier, are proposed to characterize fluctuations of acoustic resonance. Furthermore, statistical criteria based on the standard deviation of these fluctuations are proposed to assess acoustic resonance occurrence and classify its severity. The proposed criteria enable classifying between no acoustic resonance and acoustic resonance cases based upon either a two-dimensional plane, a histogram or a boxplot. These analyses are confirmed by the study of spectral variations (variations of the spectral irradiance and colorimetric parameters) as well. Standard deviations and relative standard deviations of these variations are also correlated with the presence of acoustic resonance. The results from this study show that whatever voltage envelope variations or spectral variations are significantly influenced by acoustic resonance phenomena. A set of metal halide lamps from different manufacturers and with different powers are tested in our experiments. We concluded that our designed multiplier and rectifier circuits for acoustic resonance detection have the same sensitivity as the lock-in amplifier, paving the way for the implementation of this function directly into the ballast circuit board.
36

Modelagem e controle de um reator eletrônico para lâmpadas HPS baseado na conexão diferencial de conversores CC / Modeling and control of an electronic ballast for HPS lamps based on differential connection of DC converters

Hansen, Jacson 28 February 2012 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This paper presents the development of an electronic ballast for high intensity discharge lamps, using the differential connection technique applied to Flyback converters. The power factor correction stage was implemented by a Buck-Boost converter operating in discontinuous conduction mode. Subsequently, the integrating converters technique was used to simplify the power circuit, making the power factor correction stage and Flyback converters share the same active switches. The proposed circuit was dynamically modeled, in order to obtain the mathematical parameters that govern the behavior of the ballast, obtaining the differential equations relating the voltage and current in the lamp, due to the variation of both the input voltage as the duty cycle. Digital control of the output current provided the use of a low cost microcontroller, the compensating system was designed in discrete time from the use of an integrator and a low frequency bandwidth. For effective control of lamp power, an external loop that regulates the circuit current reference was implemented. The practical implementation of the electronic ballast was performed, in order to verify the proposed control performance. / Este trabalho apresenta o desenvolvimento de um reator eletrônico para alimentar lâmpadas de descarga em alta pressão, utilizando a técnica de conexão diferencial aplicada aos conversores Flyback. A etapa de correção de fator de potencia foi implementada através de um conversor Buck-Boost operando em modo de condução descontinuo. Posteriormente, foi utilizada a técnica de integração de conversores para simplificar o circuito de potência, fazendo com que a etapa de correção do fator de potencia e os conversores Flyback compartilhassem os mesmos interruptores ativos. O circuito proposto foi modelado dinamicamente a fim de obter os parâmetros matemáticos que regem o comportamento do reator, obtendo as equações diferenciais referentes à tensão e corrente na lâmpada, em função da variação, tanto da tensão de entrada como da razão cíclica. O controle digital da corrente de saída proporcionou a utilização de um dispositivo microcontrolado de baixo custo, sendo o compensador do sistema projetado em tempo discreto a partir da utilização de um integrador e uma banda passante de baixa frequência. Para o efetivo controle da potência na lâmpada foi adicionada uma malha externa que regula a referência de corrente do circuito. Foi realizada a implementação prática do reator eletrônico a fim de verificar a performance do controle proposto.
37

Reator eletrônico ressonante orientado ao teste dimerizado de lâmpadas de vapor de mercúrio e vapor de sódio em alta pressão

Rodrigues, Cláudio Roberto Barbosa Simões 16 April 2009 (has links)
Submitted by isabela.moljf@hotmail.com (isabela.moljf@hotmail.com) on 2017-03-02T14:35:50Z No. of bitstreams: 1 claudiorobertobarbosasimoesrodrigues.pdf: 2278203 bytes, checksum: ededd970b17fc08adbb3d55174389663 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-03-06T19:43:31Z (GMT) No. of bitstreams: 1 claudiorobertobarbosasimoesrodrigues.pdf: 2278203 bytes, checksum: ededd970b17fc08adbb3d55174389663 (MD5) / Made available in DSpace on 2017-03-06T19:43:31Z (GMT). No. of bitstreams: 1 claudiorobertobarbosasimoesrodrigues.pdf: 2278203 bytes, checksum: ededd970b17fc08adbb3d55174389663 (MD5) Previous issue date: 2009-04-16 / FAPEMIG - Fundação de Amparo à Pesquisa do Estado de Minas Gerais / Este trabalho apresenta a proposta de um reator eletrônico ressonante dedicado à realização de testes de funcionalidade básica de lâmpadas de vapor de sódio e de vapor de mercúrio em alta pressão. Os testes são realizados com potência reduzida visando economizar energia elétrica e minimizar o ofuscamento dos operadores. O reator proposto é parte integrante de um sistema de reatores eletrônicos que deve substituir um conjunto de reatores eletromagnéticos utilizados em uma bancada de testes de componentes de iluminação pública. A utilização do conjunto de reatores substitutos propiciará a redução do peso e do volume da bancada, facilitando sua confecção em escala. O trabalho inclui um estudo teórico sobre lâmpadas de descarga de alta intensidade (HID) e sobre o fenômeno da ressonância acústica, que pode acometer estas lâmpadas quando são alimentadas em alta freqüência. O estudo sobre reatores eletrônicos para lâmpadas HID apresentado enfatiza o reator eletrônico série-paralelo ressonante. Este reator é utilizado neste trabalho para a realização dos testes com potência reduzida das lâmpadas de vapor de sódio em alta pressão de 70W e vapor de mercúrio em alta pressão de 125W sem a excitação do fenômeno da ressonância acústica e sem a necessidade de modificação de nenhum parâmetro do circuito. Para isto, foi desenvolvida uma metodologia para que o projeto do circuito ressonante série-paralelo pudesse atender ambas as lâmpadas em operação dimerizada. Apresentam-se ainda resultados experimentais dos testes realizados com o reator implementado. / This work presents a proposal of a resonant electronic ballast intended for the basic functionally testing of high pressure sodium and mercury lamps. The tests are performed with reduced power in order to save energy and to minimize operators’ glare effect. The proposed ballast is part of an electronic system that would replace a number of electromagnetic ballasts used in a lighting components bench test equipment. The use of this electronic system will provide the reduction of the weight and volume of the bench test equipment, favoring its commercial production. Theoretical studies about high intensity discharge lamps and acoustic resonance phenomenon, which can affect those kind of lamps in high frequency operation, are accomplished. The study of electronic ballasts for HID lamps presented emphasizes the series-parallel load resonant ballast. This ballast is used in this work for testing 70W high pressure sodium lamps and 125W high pressure mercury vapour lamps with reduced power, without exciting the acoustic resonance phenomenon and with no need of any circuit parameter modification. For this purpose, it was developed a design methodology of the series-parallel resonant circuit aiming dimmed operation of both lamps. Experimental results of tests performed with the implemented ballast are also included.
38

Změna parametrů výbojových světelných zdrojů s frekvencí napájecího proudu / Influence of Change in Frequency of the Supply Current to the Operational Parameters of the Discharge Light Sources

Kuptsov, Alexander January 2014 (has links)
The master’s thesis is devoted to exploiting of gas-discharge lamps and their dependence on frequency of the supply current. The first part describes the theory of discharge, its types and properties, terms of its origin, and ways of its exploitation. The second part concerns electrical ballast systems of gas discharge light sources, inductive (reactive) and electronic ballasts, principles of their functioning, advantages and disadvantages, and the comparison of their properties. The following chapters deal with low-pressure and high-pressure gas-discharged lamps, compare their properties and describe exploitation of fluorescent lamps. Before conducting the experiment we have described the influence of frequency of the supply current on fluorescent tube lamps. Preparations for laboratory measuring have been also implemented. During the experiment the two types of lamps have been analyzed, the results of the research are summed up in the conclusion.
39

Modes d'Alimentation et de Commande des lampes sodium haute pression en vue d’éviter les résonances acoustiques / Supply and control methods for acoustic resonances avoidance in high intensity discharge lamp

Chhun, Labo 07 May 2010 (has links)
Grâce au développement de la technologie des semi-conducteurs, les ballasts électroniques fonctionnant en haute fréquence offrent des avantages considérables par rapport aux ballasts électromagnétiques conventionnels. Il en résulte une augmentation de la durée de vie de la lampe, une diminution du volume et du poids du système et surtout un meilleur contrôle de son fonctionnement afin de réduire notamment la consommation électrique. Parmi des lampes à décharge, la lampe sodium haute pression a une excellente efficacité lumineuse et une longue durée de vie. Pourtant, quand la lampe fonctionne en haut fréquence, des perturbations de type « résonance acoustique (RA) » peuvent entraîner l’instabilité de la décharge, son extinction ou pire, la destruction de la lampe. Cette thèse, intitulée « Modes d’Alimentation et de Commande des lampes sodium haute pression en vue d’éviter les résonances acoustiques », traite de plusieurs problèmes. Les caractéristiques de la décharge haute pression, le phénomène de RA, ses conditions d’excitation (notamment au travers d’un phénomène d’hystérésis original) et la variation des paramètres électriques due à la présence de résonances acoustiques dans la lampe, ont été étudiés. Les résultats sont issus de travaux de simulation et expérimentaux menés au sein du laboratoire LAPLACE. Grâce à ces acquis fondamentaux, plusieurs nouvelles méthodes d’alimentation par l’injection de signaux à fréquences proches ont été proposées dans nos travaux. Il s’agit d’éviter la résonance acoustique dans la lampe alimentée par un ballast de structure très réduite par rapport aux solutions classiques. Cette méthode est basée sur le choix judicieux des signaux injectés dans la lampe et leur répartition, (alimentation par deux, trois ou cinq signaux, répartition symétrique, asymétrique totale ou partielle). Le résultat est un meilleur étalement du spectre et donc une réduction de puissances harmoniques sélectionnées permettant de s’adapter, à terme aux conditions d’excitation des RA, mais aussi les limitations de ces méthodes compte tenu du facteur crête. Enfin, différents types de commande en boucle fermée sont proposés, ils permettent d’assurer la stabilité de la décharge et le contrôle des puissances imposées dans la lampe. Les études théoriques, en simulation et expérimentales qui ont été conduites nous ont permis d’aboutir à des résultats concluants. / For high pressure sodium (HPS) lamps, the progress of semi-conductor technology has provided considerable advantages in the design of high frequency operated electronic ballasts, compared to conventional electromagnetic ballasts. The advantages deal with lamp lifetime improvement, ballast volume and mass reduction, and particularly with a better control of lamp operation for optimized power consumption. Among discharge lamps, high pressure sodium (HPS) lamp has excellent efficacy and long lifetime. However, when it is operated at high frequency, discharge perturbation namely “acoustic resonances (AR)” can provoke some lamp arc instabilities, extinction or, even worst, lamp destruction. The present thesis, entitled “Supply and control methods for acoustic resonances avoidance in high intensity discharge lamps” deals with several matters.  High intensity discharge (HID) characteristics, AR phenomenon, its excitation conditions (including the original features of AR hysteresis) and lamp electrical parameters variation due to AR presence, will be studied. The obtained results were provided by simulations and experimentations carried out in LAPLACE laboratory. Thanks to the acquired results of previous studies, several novel lamp supply strategies via adjacent frequency signals injection were proposed. The main concepts here consist in the avoidance of AR presented in a lamp supplied by designed electronic ballast with reduced structure, compared to classical solutions. Otherwise, the presented methods are based on pertinent choices of injected signals applied to the lamp and their frequency distributions (two, three or five signals and symmetric, partial asymmetric or total asymmetric signals). The studies actually showed better spreading of signal spectrum and power harmonic amplitudes reduction adapted to AR excitation conditions, while taking into account crest factor limitation. Finally, different control laws (PI, Hysteresis, Self-oscillation, Resonant controllers) were also proposed in order to guarantee lamp discharge stabilization and power controls. The theoretical and experimental studies including simulations were conducted to reach concluding results of our works.
40

Innovative solutions for acoustic resonance characterization in metal halide lamps / Solutions innovantes pour la caractérisation de résonances acoustiques dans les lampes à iodures métalliques

Lei, Fang 24 January 2018 (has links)
La lampe à iodure métallique est une des sources lumineuses de haute performance les plus compactes qui soit. En raison de leur bon indice de rendu des couleurs et de leur haute efficacité lumineuse, ces lampes sont souvent préférées dans les endroits où la couleur et l'efficacité sont importantes, comme les supermarchés, les gymnases, les patinoires et les arènes sportives. L’inconvénient majeur de ce type de lampe à iodure métallique vient d’un phénomène appelé « résonance acoustique ». Lorsqu’il se produit, la lumière scintille, l’arc au centre de la lampe se met à fléchir et à tourner. Cela peut aller jusqu’à l'extinction de la lampe et, dans le pire des cas, à l’explosion du tube lorsque les lampes fonctionnent dans certaines bandes de fréquence. Cette thèse se situe dans le contexte du développement de ballasts électroniques incorporant des mécanismes robustes de détection et d'évitement de résonance acoustique. À cette fin, plusieurs méthodes de détection d'enveloppe telles que le circuit multiplicateur, le circuit redresseur et l'amplificateur à verrouillage de phase sont proposées pour caractériser les fluctuations de la résonance acoustique et mieux les détecter. Des critères statistiques basés sur l'écart-type de ces fluctuations ont été établis pour détecter la présence de résonances acoustiques et les classer suivant leur gravité. Les critères proposés permettent de différencier les cas sans résonance acoustique et avec présence de résonance acoustique dans un plan bidimensionnel ou en utilisant des intervalles de confiance. Cette analyse temporelle est confirmée par l’étude des variations du spectre optique et des paramètres colorimétriques. Leurs écarts-types relatifs sont également corrélés à la présence de résonances acoustiques. Les résultats de cette étude montrent que les variations de l'enveloppe de tension ou les variations du spectre et des paramètres colorimétriques sont fortement influencées par les phénomènes de résonance acoustique Un ensemble de lampes à iodure métallique de différents fabricants et avec des puissances différentes a été testé dans nos expériences. Nous avons conclu que les circuits à multiplicateurs et a redressement permettent de détecter les résonances acoustiques avec le même niveau de sensibilité que le système à verrouillage de phase, ouvrant la voie à l’implantation de cette fonction directement au niveau du circuit du ballast. / Metal halide lamp is one kind of the most compact high-performance light sources. Because of their good color rendering index and high luminous efficacy, these lamps are often preferred in locations where color and efficacy are important, such as supermarkets, gymnasiums, ice rinks and sporting arenas. Unfortunately, acoustic resonance phenomenon occurs in metal halide lamps and causes light flicker, lamp arc bending and rotation, lamp extinction and in the worst case, arc tube explosion, when the lamps are operated in high-frequency bands. This thesis takes place in the context of developing electronic ballasts with robust acoustic resonance detection and avoidance mechanisms. To this end, several envelope detection methods such as the multiplier circuit, rectifier circuit, and lock-in amplifier, are proposed to characterize fluctuations of acoustic resonance. Furthermore, statistical criteria based on the standard deviation of these fluctuations are proposed to assess acoustic resonance occurrence and classify its severity. The proposed criteria enable classifying between no acoustic resonance and acoustic resonance cases based upon either a two-dimensional plane, a histogram or a boxplot. These analyses are confirmed by the study of spectral variations (variations of the spectral irradiance and colorimetric parameters) as well. Standard deviations and relative standard deviations of these variations are also correlated with the presence of acoustic resonance. The results from this study show that whatever voltage envelope variations or spectral variations are significantly influenced by acoustic resonance phenomena. A set of metal halide lamps from different manufacturers and with different powers are tested in our experiments. We concluded that our designed multiplier and rectifier circuits for acoustic resonance detection have the same sensitivity as the lock-in amplifier, paving the way for the implementation of this function directly into the ballast circuit board.

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