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Gestion haut niveau et suivi en ligne de l'état de santé des batteries lithium-ion / High level management and online tracking of the state of health of lithium-ion batteriesZenati, Ali 23 April 2012 (has links)
Les batteries lithium-ion sont considérées de nos jours comme la solution optimale pour les systèmes de stockage d'énergie, et cela est dû principalement à leurs hautes densités d'énergie et de puissance. Leurs performances, durées de vie, et fiabilités sont liées et dépendent des conditions d'utilisations telles que la température et les courants demandés par l'application. Et afin d'avoir un suivi de l'évolution du vieillissement de la batterie, la détermination de son état de santé (State-Of-Health -SOH-) est une fonction majeure à considérer. Ce mémoire expose les méthodologies ou techniques développées pour la gestion de la durée de vie de la batterie lithium-ion, et plus particulièrement pour la détermination de son état de santé, en se basant sur ses propres paramètres principaux qui sont la capacité et la résistance ohmique. Cette démarche permet de basculer d'un SOH statique (basé sur un modèle prédéfini de vieillissement tenant compte du calendaire et du cyclage en fonction des caractéristiques telles que la température et le courant de la batterie suivies en temps réel) vers un SOH dynamique ou auto-adaptatif, puisqu'il est basé sur un modèle du composant électrochimique dont les paramètres précédents sont évaluées en temps réel en fonction des conditions d?utilisation. Le premier chapitre revient sur les généralités concernant la technologie lithium-ion : caractéristiques, performances, constitution de l'élément de stockage, choix et nature des électrodes... Le principe de fonctionnement avec les équations générales des phénomènes électrochimiques sont aussi développés. Le second chapitre est un état de l'art des méthodologies de prédiction de la durée de vie avec les différentes classifications des modèles et des techniques de prédiction. Puis lors du troisième chapitre, nous aborderons nos méthodologies développées et les techniques utilisées, telles que le calcul statistique, la logique floue et les lois de vieillissement pour la détermination d'un état de santé dynamique de la batterie, qui en plus de la prise en compte de l'état de santé statique, c'est-à-dire basé seulement sur le vieillissement calendaire et en cyclage, considérera aussi l'évolution de la capacité et de la résistance ohmique de la batterie, en fonction du temps et des conditions d'utilisation, permettant ainsi de considérer les phénomènes improbables. Enfin dans le dernier chapitre, nous exposerons les résultats obtenus lors des tests de validations sur banc de puissance et de prototypage rapide sur des éléments réels / Lithium-ion batteries are considered nowadays as the optimal issue for the energy storage systems, it is mainly due to their high energy and power density. Their performances, lifetime, and reliability are related and depend on the operating conditions such as the temperature and requested current by the application. And in order to track the evolution of the ageing of the battery, the determination of its State-Of-Health -SOH- is a major function to consider. This thesis presents both methodologies and techniques developed for the management of the lifetime of lithium-ion battery, and more particularly the assessment of its state-of-health, based on its own main parameters which are the capacity and the ohmic resistance. This approach allows to switch from a static SOH (based on a predefined ageing model, which take into account the calendar and cycling ageing of the battery, according to some characteristics such as the temperature and the courant of the battery tracked in real time) to a dynamic SOH (self-adaptive) using an online assessment of the previous parameters according to the operating conditions. The first chapter is an overview about the lithium-ion technology: characteristics, performances, cell design, choice and nature of the electrodes... The operating principle with the general equations are also developed. The second chapter is a state of the art of the lifetime prediction methodologies with the different kinds of classification of models and prediction techniques. Then in the third chapter, we will discuss our methodologies and the developed techniques, such as the use of statistics, fuzzy logic and rules of ageing to assess a dynamic state of health of the battery, which not only does take into account the static SOH (calendar and cycling ageing), but also considers the evolution of the ohmic resistance and the capacity of the battery, depending on the time and the operating conditions. This allows taking into consideration unlikely phenomena. Finally, in the last chapter, we will expose obtained results from validation tests. These tests were done under a power electrical testbench and a rapid prototyping testbench with real cells
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[en] METROLOGICAL EVALUATION OF ZINC OXIDE VARISTORS OF MEDIUM VOLTAGE / [pt] AVALIAÇÃO METROLÓGICA DE VARISTORES DE ÓXIDO DE ZINCO PARA MÉDIA TENSÃOFERNANDO ANTONIO TUPINAMBA BARBOSA 24 June 2005 (has links)
[pt] Apesar de seus muitos benefícios, uma das poucas
desvantagens da
tecnologia do semicondutor é a vulnerabilidade dos
dispositivos de estado sólido
à temperatura, sobretensões e sobre correntes. Mesmo os
pulsos de tensão de
energia muito baixos, podem produzir interferências e
danos, às vezes com
conseqüências de grande envergadura. Assim, enquanto a
eletrônica é utilizada
em mais e mais aplicações, a temperatura, a proteção contra
sobretensão e a
supressão de transientes transformam-se em fatores de suma
importância para
o desenvolvimento de um projeto. Os varistores provaram ser
excelentes
dispositivos protetores por causa da sua flexibilidade da
aplicação e elevada
confiabilidade. Os varistores do óxido do zinco (ZnO) são
dispositivos
eletrônicos de última geração, desenvolvidos para promover
a proteção de
circuitos elétricos contra a sobretensão, causada pelas
descargas elétricas
atmosféricas, tensões induzidas e manobras elétricas, e
ideal para limitar a
corrente de pico, bem como para absorver energia. O
objetivo deste trabalho é
propor uma metodologia para avaliação metrológica de
varistores de óxido de
zinco de média tensão, visando garantir o atendimento dos
requisitos
metrológicos para a proteção de circuitos elétricos,
eletrônicos e de
telecomunicações contra a sobretensão e supressão de
transientes elétricos.
Propõe-se ainda determinar a incerteza de medição dos
parâmetros
temperatura, tensão, corrente e resistência ôhmica de
amostras comerciais de
varistores de óxido de zinco. / [en] Despite its many benefits, one of the few disadvantages of
semiconductor
technology is the vulnerability of solid state devices to
undesired increase in
temperature, voltage and current . Even low voltage pulses
can produce
interference and damages with several consequences. Thus,
as electronics are
used in more and more applications, temperature, protection
against surge and
transient suppression are becoming factors of decisive
importance in projects.
Varistors have proven to be excellent protective devices
due to their flexibility in
applications and heightened trustworthiness. The zinc oxide
varistors (ZnO) are
state of the art electronic devices of last generation,
developed to promote the
protection of electric circuits against overvoltage, caused
by atmospheric electric
discharges, induced voltages and electric maneuvers, and
suited to limit peak
current, as well as absorbing energy. The purpose of this
work is to propose a
methodology for experimental characterization of zinc oxide
varistors of average
voltage, with the purpose of guarantee the attendance of
the metrological
requirements for protection of electric, electronic and
telecommunication circuits
against transient surges and suppression of electric
transients. Uncertainty of
measurement of the parameters temperature, voltage, current
and ohmic
resistance on commercial samples of zinc oxide varistors
are also determined.
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