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Étude et mise au point d'un filtre actif d'harmoniques en vue d'améliorer la qualité de l'alimentation électrique /Beaulieu, Steeve, January 2007 (has links)
Thèse (M.Eng.) -- Université du Québec à Chicoutimi, 2007. / La p. de t. porte en outre: Mémoire présenté comme exigence partielle de la maîtrise en ingénierie. CaQCU Bibliogr.: f. [121]-124. Document électronique également accessible en format PDF. CaQCU
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Active power line conditioner with neural network controlChen, Yaow-Ming, January 1997 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1997. / Typescript. Vita. Includes bibliographical references (leaves 76-80). Also available on the Internet.
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The study of single phase diode rectifiers with high power factor and low total harmonic distortionTella, Pranavi Chowdari. Islam, Naz E. January 2008 (has links)
The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Title from PDF of title page (University of Missouri--Columbia, viewed on October 6, 2009). Thesis advisor: Dr. Naz E. Islam. Includes bibliographical references.
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Υβριδικά φίλτρα για φιλτράρισμα αρμονικών που οφείλονται σε μη γραμμικά φορτίαΔιαμάντης, Αλέξανδρος, Διαμαντής, Κωνσταντίνος 11 January 2010 (has links)
Στην παρούσα διπλωματική εργασία εξετάζονται δύο υβριδικές διατάξεις με παρόμοια συνδεσμολογία, οι οποίες χρησιμοποιούνται για το φιλτράρισμα αρμονικών σε περιπτώσεις μη γραμμικών φορτίων. Συγκεκριμένα, περιγράφονται τα χαρακτηριστικά τους, τα κυκλώματα ελέγχου τους και αναλύονται λεπτομερώς τα αποτελέσματα τους στο φιλτράρισμα.
Ιδιαίτερη βαρύτητα δίνεται στην έννοια των αρμονικών και γίνεται αναφορά στις διαταραχές που προκαλούν τα μη γραμμικά φορτία σ’ένα σύστημα ισχύος. Επιπλέον, παρουσιάζονται όλες οι κατηγορίες των υπαρχόντων αρμονικών φίλτρων και γίνονται οι απαραίτητες συγκρίσεις ανάμεσα στα δύο υβριδικά φίλτρα και στους συμβατικούς αντισταθμιστές. Τέλος, αναφέρονται τα διεθνή πρότυπα των αρμονικών και γίνεται λόγος για τις τιμές των φίλτρων στην αγορά. / In this thesis, two hybrid devices for harmonic filtering due to non linear loads are being examined.Particularly, their characteristics and their control systems are being described and their filtering performance is analysed in detail.
Attention is paid to the term of Harmonics and the distortion that the non linear loads cause to power systems. Moreover, all kinds of harmonic filters are presented and compared. Finally, there is a short reference to the international standards of harmonics and the prices of those devices in the market.
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Solucoes Psubn para os problemas da moderacao e do calculo de celula em geometria planaCALDEIRA, ALEXANDRE D. 09 October 2014 (has links)
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06501.pdf: 3346863 bytes, checksum: c0335a4d0d89d17de7ff520ce20eae25 (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
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Commande de filtres actifs parallèles sur un réseau fortement perturbé / Control of shunt active filters on a heavily perturbed networkHanna Nohra, Antoine 30 January 2017 (has links)
L’alimentation de charges non linéaires par une source d’alimentation, dans un réseau électrique, est fréquemment soumise à des perturbations et/ou déséquilibres du courant d’alimentation reçu par la charge. Les perturbations du courant d’alimentation désignent la présence d’harmoniques dans le courant d’alimentation, celui-ci n’étant alors pas sinusoïdal, ainsi que la présence d’une puissance réactive trop importante circulant sur le réseau. Les déséquilibres du courant d’alimentation se traduisent, dans un réseau polyphasé, par une mauvaise répartition des courants d’alimentation dans les différentes phases induisant un courant non nul dans le neutre côté source. En outre, dans un réseau électrique de type réseau public de distribution, ces perturbations ou déséquilibres peuvent être soumis à une réglementation du fournisseur d’énergie, c’est ainsi qu’il est utile de mettre en place un dispositif efficace pour minimiser ces perturbations et déséquilibres afin d’améliorer la qualité de l’énergie électrique. Le filtrage actif est une solution efficace qui consiste à injecter un courant adapté sur le réseau pour réduire les perturbations. Toutefois, les solutions actuelles ne permettent pas d’équilibrer les courants d’alimentation de manière efficace, et peuvent même s’avérer inefficaces pour réduire les perturbations si les tensions d’alimentation sont déséquilibrées. En outre, ces solutions ne sont généralement pas utilisable à la fois en monophasé ou en polyphasé, ni avec un fil de neutre. Le travail faisant l’objet de cette thèse vise à proposer une loi de commande générique, c’est-à-dire adaptable au cas monophasé, triphasé, polyphasé, pour un filtrage actif parallèle dont les performances (THD, facteur de déséquilibre, ..) sont améliorées par rapport à l’art existant surtout lorsque le réseau de distribution est perturbé. La recherche de solutions simples à implanter et robustes dans leur performance fait également partie de nos objectifs. La démarche est conduite par la voie de la simulation numérique et les propositions sont validées en laboratoire via une maquette expérimentale raccordée sur le réseau basse tension. A noter que les objectifs font apparaitre un caractère méthodologique fort, donnant lieu à de nombreuses déclinaisons tant par la nature du réseau (monophasé, triphasé, avec ou sans neutre, ..) que par les caractéristiques des perturbations (charges non-linéaires, déséquilibres, perturbations,....). / Feeding non-linear loads by a power source in an electric network is frequently subject to disturbances and / or unbalances in the supply current received by the load. The disturbances of the supply current denote the presence of harmonics, its waveform being non sinusoidal as well as the presence of too much reactive power circulating in the network. The unbalances in the supply current in a polyphase network (including three phase) manifest by a bad repartition of these supply currents in different phases resulting in a non-zero current in the neutral line at the source side. In addition, in a public distribution electrical network, these disturbances or unbalances may be subject to additional charges by the energy supplier, it is thus useful to implement an effective system to minimize these disturbances and unbalances in order to improve the quality of electrical energy. The active filter is an effective solution that consists in the injection of a suitable current into the network to reduce disturbance. However, the present solutions of active filters do not help to balance the supply currents efficiently, and may even be ineffective in reducing the disturbances if the supply voltages are unbalanced. Moreover, proposed solutions are generally not adapted to both single-phase or polyphase, or with a neutral wire. The work in this thesis aims to propose a generic control strategy for a shunt active filter, i.e. suitable for single-phase three phases and polyphase, whose performance (THD, unbalance factor...) are improved compared to the existing state of the art especially when the distribution system is disturbed. The quest for solutions simple to implement and robust in their performance is also part of our objectives. The proposed approach is conducted using computer simulation and validated on a laboratory experimental model connected to the low voltage network. Note that the objectives uncover a strong methodological trait, giving rise to many declensions by the nature of the network (single phase, three phases with or without neutral ...)
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Supressor eletromagnético de componentes harmônicas de sequência zeroFreitas, Stefani Carolline Leal de [UNESP] 18 February 2011 (has links) (PDF)
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Previous issue date: 2011-02-18Bitstream added on 2014-06-13T20:08:35Z : No. of bitstreams: 1
freitas_scl_me_ilha.pdf: 1038067 bytes, checksum: de418f750a6f2441df99083abd72c137 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O acelerado desenvolvimento da eletrônica de potência vem desencadeando uma série de transformações no sistema elétrico, sendo possível destacar a constante alteração da natureza das cargas consumidoras, a proliferação da co-geração e o peso crescente de questões ambientais relacionadas à questão da geração. Grande parte das cargas atuais é composta por dispositivos não-lineares que, por muitas vezes, são a causa de problemas relacionados à qualidade da energia elétrica. Considerando a variedade da distribuição sequencial das harmônicas de corrente na utilização dos filtros passivos, destacam-se os filtros e bloqueadores eletromagnéticos, os quais têm merecido especial atenção devido à sua robustez e baixo custo de implantação. Este trabalho está particularmente direcionado à investigações relacionadas ao uso desses dispositivos que possibilitam uma atenuação do fluxo das principais componentes harmônicas que compõe as distorções harmônicas de sequência zero. Neste contexto, esta dissertação apresenta contribuições inéditas relacionadas com o desenvolvimento de modelos matemáticos no domínio da frequência para bloqueadores eletromagnéticos, e um estudo de modelos matemáticos para filtros eletromagnéticos, compondo então, o aqui denominado supressor eletromagnético de componentes de sequência zero. Apresenta-se ainda, a utilização de metodologias para análise de desempenho baseado no comportamento das componentes harmônicas sequenciais. É estabelecida uma base comparativa de natureza experimental que possibilita a avaliação do desempenho e da aderência do modelo proposto. São utilizados protótipos de baixa potência de um filtro e um bloqueador, ambos eletromagnéticos, construídos a partir de análises teóricas. Os modelos desenvolvidos são utilizados na composição de um aplicativo computacional para análise... / The accelerated development of power electronics has promoted a series of changes in the electrical system, so it is possible to highlight the constant changing of consumer loads, the proliferation of co-generation and the growing importance of environmental issues related to generation. Much of the current loads are composed of non-linear devices which, in many cases are the cause of problems related to power quality. Considering the sequential distribution variety of harmonic currents in the use of passive filters, highlight the electromagnetic filters and blockers, which have received special attention due to its robustness and low cost of deployment. This work is particularly directed to investigations related to the use of these devices which enable an attenuation of the flow of the principal harmonic components that compound the zero-sequence harmonic distortion. In this context, this work presents unedited contributions related to the development of mathematical models in the frequency domain for electromagnetic blocking, and a study of mathematical models of electromagnetic filters, making then, the here called electromagnetic zero-sequence components suppressor. It presents also, the use of methodologies for performance analysis based on the sequential behavior of harmonic components. It is established a comparison basis of experimental nature that enables the performance and adherence analysis of the model. Are used a low-power prototypes of a filter and a blocker, both electromagnetic, constructed from theoretical analysis. These models are used in the composition of a software for performance analysis and optimal project of harmonic filtering systems. This tool allows an individualized and systematic investigation of the electrical system behavior for distinct harmonic sequence components. Thus, through a detailed investigation it is possible to identify appropriated actions... (Complete abstract click electronic access below)
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Desenvolvimento de programa computacional para tratamentos de dados de textura obtidos pela tecnica de difracao de raios xGALEGO, EGUIBERTO 09 October 2014 (has links)
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09670.pdf: 10232628 bytes, checksum: 1590f43108c1cbc7b2065202eea72fa8 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
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Metodo PsubN para calculos de blindagem em geometria de multiplacasDIAS, ARTUR F. 09 October 2014 (has links)
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06779.pdf: 6662459 bytes, checksum: 5a5ae589785a8bad523a922f578319f8 (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
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Estratégias de controle para operação de micro redes isoladas.ALEXANDRE, Gerônimo Barbosa. 25 April 2018 (has links)
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GERÔNIMO BARBOSA ALEXANDRE – DISSERTAÇÃO (PPGEE) 2016.pdf: 6425501 bytes, checksum: 944e1e5c2f2c2cc350f12149a5877ed1 (MD5) / Made available in DSpace on 2018-04-25T18:23:50Z (GMT). No. of bitstreams: 1
GERÔNIMO BARBOSA ALEXANDRE – DISSERTAÇÃO (PPGEE) 2016.pdf: 6425501 bytes, checksum: 944e1e5c2f2c2cc350f12149a5877ed1 (MD5)
Previous issue date: 2016-11-28 / Este trabalho foca na proposta e validação de estratégias de controle para regulação simultânea da tensão e frequência em micro redes isoladas, compensação de harmônicos de tensão no ponto comum de acoplamento (PCC) e a cooperação de potência reativa entre os diversos inversores instalados na micro rede (MG). A técnica de controle utilizada é o Controle Droop Generalizado (GDC) modificado para atender as necessidades de projeto, manter o equilíbrio entre a geração e o consumo com resposta rápida, segura, eficiente e estável. Neste cenário, seis estratégias de controle foram propostas e validadas para diferentes cenários de testes (cargas lineares e cargas não lineares) e topologias de micro redes (1 barra, 3 barras, 5 barras, 11 barras e 14 barras) sendo elas: GDC convencional, GDC ANFIS, GDC Fuzzy, GDC Adaptativo, PI Fuzzy e GDC Cooperativo com impedância virtual. A metodologia usada consistiu nas seguintes etapas: A) revisão da literatura; B) escolha das MG’s testes (padrão IEEE); C) modelagem e simulação das partes constituintes de uma MG isolada; D) projeto das estratégias de controle usadas na operação da MG; E) Validação das estratégias de controle; F) Discussão técnica dos resultados de simulação e G) Elaboração de documentos técnicos. Diante das estratégias de controle implementadas, o controlador GDC Adaptativo foi o que apresentou melhor desempenho dinâmico em malha fechada (rápido tempo de resposta, pequenas flutuações de tensão e frequência, pouca sensibilidade às flutuações da carga e da fonte energética, tornando o controle robusto e estável). Quando assistido pelas malhas internas consegue a cooperação de potência reativa e a compensação de harmônicos diante de flutuações de potência aparente tanto no consumo como na geração. As soluções propostas para regulação simultânea de tensão e frequência em MG isoladas, compensação harmônica de tensão no PCC e compartilhamento de potência reativa entre os inversores conectados na MG mostraram-se eficientes quando avaliadas em diversos cenários testes e para diversas topologias de MG, em termos de operação estável da MG, mantendo o equilíbrio entre a geração e o consumo, respondendo de forma rápida as variações operacionais, aos distúrbios de carga e as não linearidades da MG ilhada. / This work focuses on the proposal and validation of control strategies for simultaneous regulation of voltage and frequency in isolated Microgrid, voltage harmonics compensation in the common coupling point and the reactive power of cooperation between the different inverters installed in the Microgrid (MG). The used control technique is the modified generalized Droop control to meet the design needs (energy flow operation trafficked in MG), maintaining the balance between generation and consumption with rapid, safe, efficient and stable. In this scenario, six control strategies have been proposed and validated for different scenarios tests (linear and nonlinear loads) and topologies MG (1 bar, 3 bars, 5 bars, 11 bars and 14 bars) which are: conventional GDC, ANFIS GDC, GDC Fuzzy Adaptive GDC, GDC and PI Fuzzy Cooperative with virtual impedance. The methodology used consisted of the following steps: A) literature review; B) choice of MG tests (IEEE standard); C) modeling and simulation of the constituent parts of an isolated MG; D) design of the control strategies used in the MG operation; E) Validation of control strategies; F) Technical discussion of the simulation results and G) Elaboration of technical documents. Faced with the control strategies implemented, the GDC Adaptive controller showed the best dynamic performance in closed loop (fast response time, small fluctuations of voltage and frequency, low sensitivity to fluctuations in load and energy source, making the control robustness and stable). When assisted by internal loops, it achieves reactive power cooperation and harmonic compensation in the face of apparent power fluctuations in both consumption and generation. The proposed solutions for simultaneous regulation of voltage and frequency in isolated MG, harmonic voltage compensation in the PCC and reactive power sharing between the connected inverters in the MG were efficient when evaluated in several test scenarios and for several MG topologies in terms of stable MG operation, maintaining the balance between generation and consumption, responding quickly to the operational variations, load disturbances and nonlinearities of the islanded MG.
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