Dissertations / Theses on the topic 'Multiniveaux'
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Chebbah, Mohamed Talel. "Étude et simulation d'un convertisseur multiniveaux type PUC." Mémoire, École de technologie supérieure, 2014. http://espace.etsmtl.ca/1313/7/CHEBBAH_Mohamed_Talel.pdf.
Full textLe, Marrec Philippe. "Cosimulation multiniveaux dans un flot de conception multilangage." Grenoble INPG, 2000. http://www.theses.fr/2000INPG0045.
Full textIssoufou, Tiado Mahamadou. "Modèles et mécanismes multiniveaux pour les réseaux sans fil." Phd thesis, Toulouse, INPT, 2006. http://oatao.univ-toulouse.fr/7445/1/issoufoutiado.pdf.
Full textLaurent, Luc. "Stratégie multiparamétrique et métamodèles pour l'optimisation multiniveaux de structures." Phd thesis, École normale supérieure de Cachan - ENS Cachan, 2013. http://tel.archives-ouvertes.fr/tel-00972299.
Full textRalaivao, Rajaonimaria Hugues. "Commande des structures matricielles multiniveaux : application au convertisseur NPC." Lille 1, 1999. https://pepite-depot.univ-lille.fr/LIBRE/Th_Num/1999/50376-1999-455.pdf.
Full textIssoufou, Tiado Mahamadou Beylot André-Luc. "Modèles et mécanismes multiniveaux pour les réseaux sans fil." Toulouse : INP Toulouse, 2006. http://ethesis.inp-toulouse.fr/archive/00000277.
Full textLeredde, Alexandre. "Etude, Commande et Mise en Oeuvre de Nouvelles Structures Multiniveaux." Phd thesis, Institut National Polytechnique de Toulouse - INPT, 2011. http://tel.archives-ouvertes.fr/tel-00668376.
Full textMerval, Antoine. "Application des modèles réduits à l'optimisation multiniveaux d'une structure aéronautique." Toulouse, ISAE, 2008. http://www.theses.fr/2008ESAE0015.
Full textGrégo, Laurence. "Méthodes multiniveaux pour des problèmes de contact unilatéral avec frottement." Aix-Marseille 1, 1995. http://www.theses.fr/1995AIX11059.
Full textPerrier, Robin. "Etude et réalisation de disques optiques multiniveaux inscriptibles une fois." Grenoble INPG, 2003. http://www.theses.fr/2003INPG0134.
Full textAhmadouche, Ahmed Abdelkader. "Modélisation électrique des interconnexions multiniveaux en présence de diélectriques stratifiés." Grenoble INPG, 1987. http://www.theses.fr/1987INPG0140.
Full textLeredde, Alexandre. "Etude, commande et mise en œuvre de nouvelles structures multiniveaux." Thesis, Toulouse, INPT, 2011. http://www.theses.fr/2011INPT0094/document.
Full textThis PhD Thesis deals with the study of new multilevel structures. At the beginning of this work, a new methodology to create new multilevel structures has been conceived. To evaluate the performances of these structures, there are many possibilities: number of output voltage levels, number of components, and the quality of the converters’ output waveforms. The list of criteria is not exhaustive. One technique to obtain an output multilevel waveform is to split the DC link in several capacitors. There is a limitation since putting more than two capacitors in serial connection leads to an unbalancing of these voltage capacitors. Several solutions are possible to balance these voltages. The first one uses the control of the structure in a three phase application, using a space vector modulation and minimizing the energy stored in the DC link. The second solution consists in using auxiliary circuits, which realize an energy transfer between one capacitor to another through an inductor. The drawback of this method is the high number of components. This problem can be reduced sharing some components between the three phases of the converter. The third part of this study is related to multicell converters, structures with very interesting good properties. New converter structures mix serial and parallel multicell converters, to obtain a hybrid converter with similar performances to the two basic converters. An experimental prototype was built to validate the results of the PhD. The digital control of this hybrid structure was made with a FPGA where two DSP processors were implemented
Ahmadouche, Ahmed. "Modélisation électrique des interconnexions multiniveaux en présence de diélectriques stratifiés." Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb376021511.
Full textGuennegues, Virginie. "Contribution l'étude des convertisseurs multiniveaux destinés aux applications moteurs rapides." Thesis, Vandoeuvre-les-Nancy, INPL, 2009. http://www.theses.fr/2009INPL094N/document.
Full textThis PhD thesis deals with multilevel inverters dedicated to high speed motors applications, used in Oil \& Gas applications. The main objective is to study a topology which enables reducing switching losses, in comparison with the conventional 3-level NPC (Neutral Point Clamped) topology. Moreover, the inverter has to provide motor input signals with a low harmonic distortion level, not to create undesired additional heating in the motor. After a study of the existing topologies, the 3-level NPP (Neutral Point Piloted) topology is chosen regarding all its benefits. Indeed, thanks to series connection of semi-conductor components, switching losses can be divided by two compared to homologous components on the NPC topology. After having compared NPC and NPP topologies in terms of waveforms and losses distribution in components, the author interest is the experimental validation of this topology. The performances reached by the NPP inverter are interesting because it enables to switch two times faster than for a NPC topology for a given current or to switch a higher current for a given switching frequency. The switching schemes of the NPP leg are studied to understand the gain obtained on this topology. In spite of the fact that switching frequency can be doubled on the NPP topology, the sinus filter can not be avoided in order to respect harmonic specification on the motor. A sinus filter with coupled inductances is introduced so that to responds the different sizing criteria
Becker, Florent. "Contribution à la continuité de service des convertisseurs statiques multiniveaux." Thesis, Université de Lorraine, 2017. http://www.theses.fr/2017LORR0202/document.
Full textThis thesis deals with continuity of service of multilevel power converters, during the failure of one of their power components. The studied converter topologies are the following, widely used in industrial applications: Neutral Point Clamped (NPC) and Neutral Point Piloted (NPP) or T-Type. First, to reduce the failure rate of the converter, an advanced control is proposed ; it increases the lifetime of the power components by minimizing the number of switchings over a period. This idea is based on the fact that a multilevel converter makes possible to generate the same output voltage level from several different switching sequences. The principle of the proposed control will be developed in a general way. Then, it is applied to the cases of 5-level "H-bridge" topologies, NPP (or T-Type) and NPC. Then, the continuity of service in nominal mode is studied for a 5 level "H-brige" NPP (or T-Type) converter, when an open circuit failure occurs on a power component. We first propose a fault diagnosis, consisting in a fault detection step, followed by the location of the faulty component. Then, an original fault-tolerant converter topology will ensure the continuity of service of the system, by modifying the control according to the localized faulty component. Reconfigurable digital electronic architectures based on Field Programmable Gate Array (FPGA) components will be dedicated to the diagnosis and the reconfiguration of the control; they will perform high temporal performances. All the results presented in this paper are validated by modeling and simulation. Then, they are experimentally validated on a test bench
Becker, Florent. "Contribution à la continuité de service des convertisseurs statiques multiniveaux." Electronic Thesis or Diss., Université de Lorraine, 2017. http://www.theses.fr/2017LORR0202.
Full textThis thesis deals with continuity of service of multilevel power converters, during the failure of one of their power components. The studied converter topologies are the following, widely used in industrial applications: Neutral Point Clamped (NPC) and Neutral Point Piloted (NPP) or T-Type. First, to reduce the failure rate of the converter, an advanced control is proposed ; it increases the lifetime of the power components by minimizing the number of switchings over a period. This idea is based on the fact that a multilevel converter makes possible to generate the same output voltage level from several different switching sequences. The principle of the proposed control will be developed in a general way. Then, it is applied to the cases of 5-level "H-bridge" topologies, NPP (or T-Type) and NPC. Then, the continuity of service in nominal mode is studied for a 5 level "H-brige" NPP (or T-Type) converter, when an open circuit failure occurs on a power component. We first propose a fault diagnosis, consisting in a fault detection step, followed by the location of the faulty component. Then, an original fault-tolerant converter topology will ensure the continuity of service of the system, by modifying the control according to the localized faulty component. Reconfigurable digital electronic architectures based on Field Programmable Gate Array (FPGA) components will be dedicated to the diagnosis and the reconfiguration of the control; they will perform high temporal performances. All the results presented in this paper are validated by modeling and simulation. Then, they are experimentally validated on a test bench
Minjeaud, Sebastian. "Raffinement local adaptatif et méthodes multiniveaux pour la simulation d'écoulements multipĥasiques." Phd thesis, Université Paul Cézanne - Aix-Marseille III, 2010. http://tel.archives-ouvertes.fr/tel-00535892.
Full textMinjeaud, Sebastian. "Raffinement local adaptatif et méthodes multiniveaux pour la simulation d’écoulements multiphasiques." Aix-Marseille 3, 2010. http://www.theses.fr/2010AIX30051.
Full textThis manuscript describes some numerical and mathematical aspects of incompressible multiphase flows simulations with a diffuse interface Cahn-Hillliard/Navier-Stokes model (interfaces have a small but a positive thickness). The space discretisation is performed thanks to a Galerkin formulation and the finite elements method. The presence of different scales in the system (interfaces have a very small thickness compared to the characteristic lengths of the domain) suggests the use of a local adaptive refinement method. The algorithm, that we introduced, allows to implicitly handle the non conformities of the generated meshes to produce conformal finite elements approximation spaces. It consists in refining basis functions instead of cells. The refinement of a basis function is made possible by the conceptual existence of a nested sequence of uniformly refined grids from which “parent-child” relationships are deduced, linking the basis functions of two consecutive refinement levels. Moreover, we show how this method can be exploited to build multigrid preconditioners. From a composite finite elements approximation space, it is indeed possible to rebuild, by “coarsening”, a sequence of auxiliairy nested spaces which allows to enter in the abstract multigrid framework. Concerning the time discretization, we begin by the study of the Cahn-Hilliard system. A semi-implicit scheme is proposed to remedy to convergence failures of the Newton method used to solve this (non linear) system. It guarantees the decrease of the discrete free energy ensuring the stability of the scheme. We show existence and convergence of discrete solutions towards the weak solution of the system. We then continue this study by providing an inconditionnaly stable time discretization of the complete Cahn-Hilliard/Navier-Stokes model. An important point is that this discretization does not strongly couple the Cahn-Hilliard and Navier-Stokes systems allowing to independently solve the two systems in each time step. We show the existence of discrete solutions and, in the case where the three fluids have the same densities, we show their convergence towards weak solutions. We study, to finish this part, different issues linked to the use of the incremental projection method. Finally, the last part presents several examples of numerical simulations, diphasic and triphasic, in two and three dimensions
Baudesson, Philippe. "Sûreté de fonctionnement, reconfiguration et marches dégradées des onduleurs multiniveaux à IGBT." Toulouse, INPT, 2000. http://www.theses.fr/2000INPT027H.
Full textZegour, Djamel Eddine. "Extensions du hachage digital : hachage digital multiniveaux, hachage digital avec représentations séquentielles... /." Le Chesnay : Institut national de recherche en informatique et en automatique, 1988. http://catalogue.bnf.fr/ark:/12148/cb349542450.
Full textBen, Abdelghani Hafedh. "Étude, conception et réalisation d'un convertisseur statique hybride multiniveaux tolérant aux défauts." Thesis, Toulouse, INPT, 2016. http://www.theses.fr/2016INPT0042/document.
Full textGiven the importance of power converter safety operation in several fields (electric traction, renewable energy, etc ..), it is necessary to examine availability of these systems in the case of malfunction of an IGBT module, a converter leg or a phase machine. Thus, it is essential to develop new hardware architectures and software controls capable of operating at significant power after fault occurence. This thesis deals with a new multilevel fault tolerant hybrid topology. It consists on adding to a 3-phase 3-level NPC (Neutral Point Clamped) inverter, a fourth 3-level FC (Flying Cap) leg. New techniques of fault tolerance parts, namely detection, isolation, reconfiguration and system control during post fault mode, are proposed, analyzed and validated with a 15kW experimental converter prototype
Fahrni, Claude. "Principe d'alimentation par convertisseurs multiniveaux à stockage intégré : application aux accélérateurs de particules /." [S.l.] : [s.n.], 2008. http://library.epfl.ch/theses/?nr=4034.
Full textChabert, Christophe. "Etude et modélisation de convertisseurs multiniveaux à commutation douce en vue d'applications navales /." [S.l.] : [s.n.], 2003. http://library.epfl.ch/theses/?nr=2771.
Full textMariéthoz, Jean-Sébastien. "Etude formelle pour la synthèse de convertisseurs multiniveaux asymétriques : topologies, modulation et commande /." [S.l.] : [s.n.], 2005. http://library.epfl.ch/theses/?nr=3188.
Full textMissanda, Mavoungou Arsène. "Étude des systèmes éoliens raccordés au réseau électrique à l'aide de convertisseurs multiniveaux." Mémoire, École de technologie supérieure, 2014. http://espace.etsmtl.ca/1293/1/MISSANDA_MAVOUNGOU_Ars%C3%A8ne.pdf.
Full textHermawan. "Contribution à la stabilité dynamique des réseaux multimachines par introduction de commande multiniveaux." Ecully, Ecole centrale de Lyon, 1995. http://www.theses.fr/1995ECDL0025.
Full textWeynans, Lisl. "Méthode particulaire multiniveaux pour la dynamique des gaz : application au calcul d'écoulements multifluides." Université Joseph Fourier (Grenoble), 2006. http://www.theses.fr/2006GRE10292.
Full textThis work is devoted to the evaluation of the ability of a particle-mesh method, inspired from Vortex-In-Cell methods, to simulate gaz dynamics, especially multifluids. We firstly develop a particle-mesh method, associated with a conservative remeshing step, which is performed with high order interpolating kernels. We study theoretically and numerically this method. This analysis gives evidence of a strong relationship between the particle method and high order Lax-Wendroff-like finite difference schemes. We introduce a new scheme, more accurate, for the advection of particles. Then we implement a multilevel technique, inspired from AMR, which allows to increase locally the accuracy of the computations. Finally we develop a level-set like technique, discretized on the particles, to simulate the interface between compressible flows. We use the multilevel technique to improve the interface resolution and the conservation of partial masses
Bindel, Sébastien. "Algorithmique et applications pour les flottes hétérogènes multiniveaux de matériels mobiles communicants autonomes." Thesis, Bordeaux, 2016. http://www.theses.fr/2016BORD0172/document.
Full textUnmanned vehicles are defined as autonomous entities with no operator on board. They are a part of a global system called Unmanned System which also includes elements such as a control station. These vehicles are designed to fulfil the requirements of assigned missions and can be deployed in spatial, aerial, terrestrial and maritime environments. Since a mission cannot be accomplished with a single vehicle, vehicles have to cooperate in order to achieve a global mission. However, cooperation requires communication interoperability between all vehicles. Even if previous works have standardized application protocols, it is not sufficient to ensure data delivery between all vehicles, since they have a specific mobility pattern and sometimes different network interfaces. The main goal of this thesis is to offer a seamless network, including all kinds of unmanned systems. We propose a cross layer approach in order to route and deliver data to any vehicle. In this context, each vehicle is able to transmit data to another without information on the global topology. We have developed a routing protocol, which adapts its strategy, according to the contextand to the network environment. In addition, we exploit the any cast diffusion technique based on vehicles features in order to adopt an optimal routing scheme
Serbia, Nicola. "Convertisseurs modulaires multiniveaux pour le transport d'énergie électrique en courant continu haute tension." Thesis, Toulouse, INPT, 2014. http://www.theses.fr/2014INPT0007/document.
Full textThis work was performed in the frame of collaboration between the Laboratory on Plasma and Energy Conversion (LAPLACE), University of Toulouse, and the Second University of Naples (SUN). This work was supported by Rongxin Power Electronic Company (China) and concerns the use of multilevel converters in High Voltage Direct Current (HVDC) transmission. For more than one hundred years, the generation, the transmission, distribution and uses of electrical energy were principally based on AC systems. HVDC systems were considered some 50 years ago for technical and economic reasons. Nowadays, it is well known that HVDC is more convenient than AC for overhead transmission lines from 800 - 1000 km long. This break-even distance decreases up to 50 km for underground or submarine cables. Over the twenty-first century, HVDC transmissions will be a key point in green electric energy development. Due to the limitation in current capability of semiconductors and electrical cables, high power applications require high voltage converters. Thanks to the development of high voltage semiconductor devices, it is now possible to achieve high power converters for AC/DC conversion in the GW power range. For several years, multilevel voltage source converters allow working at high voltage level and draw a quasi-sinusoidal voltage waveform. Classical multilevel topologies such as NPC and Flying Capacitor VSIs were introduced twenty years ago and are nowadays widely used in Medium Power applications such as traction drives. In the scope of High Voltage AC/DC converters, the Modular Multilevel Converter (MMC), proposed ten years ago by Professor R. Marquardt from the University of Munich (Germany), appeared particularly interesting for HVDC transmissions. On the base of the MMC principle, this thesis considers different topologies of elementary cells which make the High Voltage AC/DC converter more flexible and easy suitable respect to different voltage and current levels. The document is organized as follow. Firstly, HVDC power systems are introduced. Conventional configurations of Current Source Converters (CSCs) and Voltage Source Converters (VSCs) are shown. The most attractive topologies for VSC-HVDC systems are analyzed. The operating principle of the MMC is presented and the sizing of reactive devices is developed by considering an open loop and a closed loop control. Different topologies of elementary cells offer various properties in current or voltage reversibility on the DC side. To compare the different topologies, an analytical approach on the power losses evaluation is achieved which made the calculation very fast and direct. A HVDC link to connect an off-shore wind farm platform is considered as a case study. The nominal power level is 100 MW with a DC voltage of 160 kV. The MMC is rated considering press-packed IGBT and IGCT devices. Simulations validate the calculations and also allow analyzing fault conditions. The study is carried out by considering a classical PWM control with an interleaving of the cells. In order to validate calculation and the simulation results, a 10kW three-phase prototype was built. It includes 18 commutation cells and its control system is based on a DSP-FGPA platform
Song, Manguelle Joseph Song Manguelle Joseph. "Convertisseurs multiniveaux asymétriques alimentés par transformateurs multi-secondaires basse-fréquence : réactions au réseau d'alimentation /." [S.l.] : [s.n.], 2004. http://library.epfl.ch/theses/?nr=3033.
Full textVoge, Marie-Emilie. "Optimisation des réseaux de télécommunications : Réseaux multiniveaux, Tolérance aux pannes et Surveillance du trafic." Phd thesis, Université de Nice Sophia-Antipolis, 2006. http://tel.archives-ouvertes.fr/tel-00171565.
Full textNous nous intéressons aussi bien aux réseaux de coeur qu'aux réseaux d'accès. Dans le premier chapitre, nous présentons brièvement les réseaux d'accès ainsi que les réseaux multiniveaux de type IP/WDM et l'architecture MPLS que nous considérons pour les réseaux de coeur. Ces réseaux sont composés d'un niveau physique sur lequel est routé un niveau virtuel. A leur tour les requêtes des utilisateurs sont routées sur le niveau virtuel. Nous abordons également la tolérance aux pannes dans les réseaux multiniveaux qui motive deux problèmes que nous avons étudiés.
Le second chapitre est consacré à la conception de réseaux virtuels. Dans un premier temps nous modélisons un problème prenant en compte la tolérance aux pannes, puis nous en étudions un sous-problème, le groupage. Notre objectif est de minimiser le nombre de liens virtuels, ou tubes, à installer pour router un ensemble de requêtes quelconque lorsque le niveau physique est un chemin orienté.
Le troisième chapitre traite des groupes de risque (SRRG) induits par l'empilement de niveaux au sein d'un réseau multiniveaux. Grâce à une modélisation par des graphes colorés, nous étudions la connexité et la vulnérabilité aux pannes de ces réseaux.
L'objet du quatrième chapitre est le problème du placement d'instruments de mesure du trafic dans le réseau d'accès d'un opérateur. Nous considérons aussi bien les mesures passives qu'actives. La surveillance du trafic possède de nombreuses applications, en particulier la détection de pannes et l'évaluation des performances d'un réseau.
Videt, Arnaud. "Variateur de vitesse à impact électromagnétique réduit : onduleur multiniveaux et nouvelles stratégies de modulation." Phd thesis, Ecole Centrale de Lille, 2008. http://tel.archives-ouvertes.fr/tel-00365461.
Full textMedir, Tejado Lluís. "Interdépendances institutionnelles et gouvernance multiniveaux : le cas des municipalités et de la politique éducative." Thesis, Toulouse 1, 2013. http://www.theses.fr/2013TOU10067/document.
Full textLe résumé en anglais n'a pas été communiqué par l'auteur
Este trabajo pretende analizar el cambio institucional operado en los gobiernos locales en materia educativa. Los gobiernos locales han mostrado una capacidad creciente de participar en la prestación de políticas educativas, y han evolucionado institucionalmente para poder hacerlo. El trabajo demuestra que el proceso de institucionalización de las capacidades educativas de los municipios se ha realizado básicamente a partir de la firma de instrumentos colaborativos. Los datos obtenidos del vaciado de 6323 convenios catalanes y 200 Contrats Éducatifs Locaux franceses, permiten estudiar las relaciones intergubernamentales que se generan entre gobiernos locales y sus respectivos centros políticos en un entorno multinivel. El análisis se basa en los municipios catalanes y toma también como referente el caso francés. La hipótesis principal de este trabajo es que en materia educativa el cambio se puede explicar en función el grado de intensidad relacional con el “centro político”. El trabajo muestra que en un marco institucional tan complejo como el educativo los convenios también reflejan las jerarquías y características propias del diseño del conjunto del sistema. Así, los gobiernos locales no consiguen evolucionar y cambiar institucionalmente de forma autónoma, sino condicionados por su relación con el centro político. El sistema de interdependencias generado le permite al centro mantener la configuración de los servicios que se implementan a nivel local, el diseño general de la política, y los criterios de la distribución de recursos. En definitiva, el sistema de relaciones intergubernamentales permite a los centros políticos respectivos dirigir el proceso de capacitación educativa municipal, porque le permite modular la intensidad de las relaciones con los municipios. El trabajo presenta un análisis empírico basado en tres bases de datos creadas específicamente para este trabajo, y que permiten aplicar técnicas de análisis cuantitativo en la construcción de un índice de capacidad institucional y ponen a prueba las principales hipótesis del trabajo Así, las dos grandes conclusiones del trabajo son que: el cambio institucional de los gobiernos locales en materia educativa se dirige desde el centro político, descartando la autonomía municipal (1), y que se produce fundamentalmente mediante el establecimiento de interdependencias institucionales (2). En definitiva, para comprender el proceso de institucionalización de los gobiernos locales en educación, no sólo es necesaria una visión bottom-up, sino que también es fundamental entender el proceso como fruto de unas todavía poderosas relaciones de poder verticales
Martins, Carlos de Almeida. "Contrôle direct du couple d'une machine asynchrone alimentée par convertisseur multiniveaux à fréquence imposée." Doctoral thesis, Toulouse, INPT, 2000. http://hdl.handle.net/10216/11690.
Full textVoge, Marie-Émilie. "Optimisation des réseaux de télécommunications : réseaux multiniveaux, tolérance aux pannes et surveillance du trafic." Nice, 2006. http://www.theses.fr/2006NICE4085.
Full textThis thesis is devoted to optimization problems arising in telecommunication networks. We tackle these problems from two main points of view. On the one hand we study their complexity and approximability properties. On the second hand, we propose heuristic methods, approximation algorithms or even exact algorithms that we compare with mixed integer linear programming formulations on specific instances. We are interested in backbone networks as well as access networks. In the first chapter, we briefly present access networks and IP/WDM multilayer backbone networks using the MPLS architecture. These networks are composed of a physical layer on which is routed a virtual layer. In turn, the users' requests are routed on the virtual layer. We also present multilayer network survivability issues motivating two of the questions we have studied. The second chapter is dedicated to the design of virtual networks. First we propose a mixed integer linear programming formulation with network survivability constraints. Then we study a sub-problem, the grooming problem. Our objective is to minimize the number of virtual links, needed to route a given set of requests when the physical layer is a directed path. The third chapter deals with Shared Risk Resource Groups (SRRG) induced by stacking up network layers in multilayer networks. Thanks to the colored graphs model, we study connexity and failure vulnerability of these networks. The positioning of active and passive traffic measurement points in the access network of an internet service provider is the subject of the fourth chapter
Achchab, Boujemâa. "Estimations d'erreur a posteriori, éléments finis mixtes hiérarchiques, méthodes de stabilisation et méthodes multiniveaux." Lyon 1, 1995. http://www.theses.fr/1995LYO10239.
Full textHaederli, Christoph. "Convertisseurs multiniveaux à bus continu avec point milieu : nouvelles topologies et stratégies de contrôles." Toulouse, INPT, 2008. http://ethesis.inp-toulouse.fr/archive/00001951/.
Full textIn this thesis, a new concept for the representation, the analysis and synthesis of ML (multi level) converters is introduced. This concept allows simple comprehension, comparison and classification of topologies. The family of ML converters with 3 level split DC link supply has been studied more indepth. The converter structures of this family allow for ML output generation while providing good controllability and reasonable components dimensioning. In addition to the known SMC (stacked multi cell converter) and ANPC (active neutral point clamped converter), new topologies are introduced and the functional limitations are studied. Control concepts based on CM (common mode) voltage injection and based on the use of redundant states are introduced. The performance can be significantly improved compered to state of the art control schemes
Pérezts, Mar. "L'éthique comme pratique située : étude multiniveaux sur l'éthique au travail dans la conformité bancaire." Thesis, Paris 1, 2014. http://www.theses.fr/2014PA010058.
Full textWhither ethics in banking? This question has increasingly pervaded media and academic concerns since the outbreak of the 2007 financial crisis, and has also triggered this dissertation. Beyond the current turmoil on the one hand, and avoiding a normative approach on the other, this study focuses on ethics in the making, on ethics at work in organizing and organizations, that is and ethics understood essentially as practice. Our perspective considers ethics in situ, from a practice and situational approach and not solely from either the standpoint of discourse or that of norms and their effective compliance. This allows us precisely to apprehend in a transversal and integrated way the link between ethics as process and such discourses and norms within organizing. Through an ethnographic study of a major French Investment Bank's Anti-Money Laundering Compliance unit, this thesis focuses on ethics in the making, and the work of ‘ethics as situated practice’. We propose and define this syntagma to consider ethics as an organizational phenomenon, which we define as 1) complex and dynamic, 2) simultaneously embedded at the micro (within moral subjects), meso (within human organisations) and macro (at the institutional level), and 3) in an engaged loop circling back to its situation. The context of banking compliance is of great relevance for this study, particularly in times of financial and values crisis, since it exacerbates the specific tensions and stakes that challenge on a daily basis ethics in its constant relation with norms, risks and the imperative of compliance
Martins, Carlos de Almeida. "Contrôle direct du couple d'une machine asynchrone alimentée par convertisseur multiniveaux à fréquence imposée." Tese, Toulouse, INPT, 2000. http://hdl.handle.net/10216/11690.
Full textRynkiewicz, Pedro. "Contribution à la mise en oeuvre de synthèse de filtres accordables simultanément en fréquence et bande passante : application aux fréquences millimétriques et submillimétriques en technologie BiCMOS." Phd thesis, Toulouse, INPT, 2018. http://oatao.univ-toulouse.fr/23646/1/Rynkiewicz_Pedro.pdf.
Full textBouhali, Omar. "CONTRIBUTION DES CONVERTISSEURS MULTINIVEAUX AU RACCORDEMENT DE LA PRODUCTION D'ORIGINE EOLIENNE SUR UN RESEAU ELECTRIQUE." Phd thesis, Ecole Centrale de Lille, 2007. http://tel.archives-ouvertes.fr/tel-00152745.
Full textDru, Frédéric. "Décodage à seuil itératif des codes convolutionnels doublement orthogonaux perforés et application aux modulations multiniveaux." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/MQ65572.pdf.
Full textRomero, Rodríguez Miguel. "Synthèse de contrôle par supervision pour des systèmes HVDC à base de convertisseurs modulaires multiniveaux." Thesis, Lyon, 2018. http://www.theses.fr/2018LYSEI081.
Full textThe growth of renewable energy production is changing the future of power transmission systems. In recent years, High-Voltage Direct Current (HVDC) technologies based on Modular Multilevel Converters (MMC) are embraced by industry and academia as a solution for the efficient integration of renewable energies into electrical grids. However, this type of technology introduces new challenges in the way power transmission systems are controlled and operated, as faster and more complex control strategies will be needed in a domain which nowadays relies heavily on human decision. In this context, Discrete Event Systems (DES) modeling and Supervisory Control Theory (SCT) are powerful tools for the synthesis of supervisors ensuring that the system to be controlled respects a set of behavioral specifications, imposed by the designer, within its physical limitations. This work proposes a method for the full development, from conception to implementation, of the supervisory control of a multi-terminal DC (MTDC) system. A functional analysis on the considered system has been done so as to identify the main components and operational modes of the grid. Then, the proposed solution is based on the discrete-event modeling of the continuous-time behavior of the components in the system. From there, SCT concepts are applied so as to obtain a hierarchical control architecture taking into account the priority of some control actions that should be treated at the local level. Furthermore, the obtained discrete controllers present a mode-switching structure in order to realize mode management during the operation of the MTDC grid. Finally, a method for the implementation of the obtained controllers in widespread power system simulation software is proposed. The whole work has been validated through the simulation of a case study, involving the mode management of a 3-terminal bipolar MTDC system
Hadbi, Djamel. "Formulations de problèmes d’optimisation multiniveaux pour la conception de réseaux de bord électriques en aéronautique." Thesis, Université Grenoble Alpes (ComUE), 2015. http://www.theses.fr/2015GREAT115/document.
Full textWithin more electric aircraft context, electric systems and networks have to evolve. High energy density integration pushes designers to reconsider their systems, architectures and tools.An aircraft network contains a large number of multidisciplinary systems which come from different manufacturers. Each manufacturer designs its system separately following quality standards specified by the aggregator. The goal of this thesis is to provide system approaches which could deal with the high-level of complexity of the network while reaching the optimal design of all the system and so reduce the total weight in comparison with mechanistic approaches based on independent optimization loops for the different subsystems.Consulting MDO “Multidisciplinary Design Optimization” researches, we have developed a multilevel approach based on our previous studies and conclusions on classical approaches used in the design of electrical systems. The optimization concerns the input filters of the loads connected to the HVDC bus and the output filter of the generating channel which supply the electric power. The multilevel collaborative optimization allows an automated exchange of data between the aggregator (system level) and manufacturers (sub-system level) and thanks to that, the optimal design of all the system is joined. The strong points of this approach are the aggregated formulation and causality connections between sub-systems
Escaig, Yves. "Décomposition de domaines multiniveaux et traitements distribués pour la résolution de problèmes de grande taille." Compiègne, 1992. http://www.theses.fr/1992COMPD539.
Full textBouhali, Omar. "Contribution des convertisseurs multiniveaux au raccordement de la production d'origine éolienne sur un réseau électrique." Ecole Centrale de Lille, 2007. https://pepite-depot.univ-lille.fr/LIBRE/Th_Num/2007/50376-2007-Bouhali.pdf.
Full textThis work deals with the evaluation of the possibilities which offers the multilevel converters for the connection of a wind generation system including a storage system. First of all, modeling and control of the connection are given. Classically, the grid converter is controlled to regulate the intermediate continuous bus. The use of a NPC converter topology requires the balancing of the DC-bus voltage. A solution based on the redundant configurations is proposed. Then, the modeling and the control of a three-phase multilevel inverter are presented by extending the presented concepts, which are established by using the vectorial mathematical tools. The storage unit is used to control the continuous bus and consequently compensate the fluctuations of the wind power. The energy supervision of the association of both sources is presented and the operation range is given. Various possibilities of the connection of both sources are proposed and evaluated. Experimental validations are given. Finally, the use of a converter using four series capacitors in the DC-bus is developed for the multi source system connections. Various possibilities of connection on this continuous bus are investigated. The supervision system of the powers for each case is also given
Tehrani, Kambiz Arab. "Conception, Synthèse et Application d’une Nouvelle Commande Robuste par PID Fractionnaire pour Les Onduleurs Multiniveaux." Thesis, Vandoeuvre-les-Nancy, INPL, 2010. http://www.theses.fr/2010INPL074N/document.
Full textThis thesis presents a new extension of multilevel inverters, called 'Multi Neutral Point' (MNP). This topology is deduced from Neutral Point Clamped (NPC) and Multi Point Clamped (MPC) structures. The advantage of this extension is twofold: the absence of clamping diodes and the possibility of operating on all the numbers of levels (even and odd). We have developed a simple command; we first present the command strategy for a three levels MNP, then for a five level MNP. We have compared the power losses in the power switches of an MNP and an NPC. The power losses for an MNP are far below those of the NPC inverter. For this inverter model, we have chosen a robust current control by a fractional PID controller. This control strategy can sharply reduce the amplitude and the phase errors between the reference current and the load one. This method requires the setting of various control parameters thanks to the principle of ‘’multiobjective optimization.'' In the end the set of converter-control command is validated by simulation and experimentation; the simulated and experimental results match very well
Ahmadi, Sajjad. "Contribution à l'étude de la tolérance de pannes de convertisseurs multiniveaux en pont en H." Electronic Thesis or Diss., Université de Lorraine, 2021. http://www.theses.fr/2021LORR0026.
Full textEnsuring service continuity in safety-critical applications is indispensable. In some of these applications, the multilevel inverters play a vital role. Hence, employing a multilevel converter with fault tolerant feature is of great importance. In this regard, a fault tolerant five-level Neutral Point Clamped (NPC) inverter is proposed in this research work. The proposed fault diagnosis algorithm is based on failure mode analysis, which is a logic based approach. The realization of this strategy does not require any component modeling and complicated calculations. Although switches are more fragile than clamping diodes, clamping diodes are also subjected to breakdown. Hence, identification of a defective clamping diode is also studied in this research work. Moreover, for fault detection procedure, a voltage quantifier is proposed to avoid any misdiagnosis arising from measurement errors and voltage drop in the circuit. Following to the fault diagnosis, the proposed fault tolerant strategy aims to restore the rated voltage and current at the inverter terminal in the presence of an open-circuit fault in a switch or in a clamping or anti-parallel diode. Compared with healthy operation, harmonic content of the terminal voltage and current is not increased. The proposed fault tolerant structure does not include any contactor or bidirectional switch, which allows fast triggering of fault tolerant operation. The simulation and experimental results are presented to validate the effectiveness of the proposed approaches. A fault is detected in 20 µs and localized between 20 and 60 µs after occurrence, depending on the faulty semiconductor (switch or clamping diode)
Tehrani, Kambiz Arab. "Conception, Synthèse et Application d’une Nouvelle Commande Robuste par PID Fractionnaire pour Les Onduleurs Multiniveaux." Electronic Thesis or Diss., Vandoeuvre-les-Nancy, INPL, 2010. http://www.theses.fr/2010INPL074N.
Full textThis thesis presents a new extension of multilevel inverters, called 'Multi Neutral Point' (MNP). This topology is deduced from Neutral Point Clamped (NPC) and Multi Point Clamped (MPC) structures. The advantage of this extension is twofold: the absence of clamping diodes and the possibility of operating on all the numbers of levels (even and odd). We have developed a simple command; we first present the command strategy for a three levels MNP, then for a five level MNP. We have compared the power losses in the power switches of an MNP and an NPC. The power losses for an MNP are far below those of the NPC inverter. For this inverter model, we have chosen a robust current control by a fractional PID controller. This control strategy can sharply reduce the amplitude and the phase errors between the reference current and the load one. This method requires the setting of various control parameters thanks to the principle of ‘’multiobjective optimization.'' In the end the set of converter-control command is validated by simulation and experimentation; the simulated and experimental results match very well
Abdayem, Anthony. "Stratégies de contrôle optimisées pour les convertisseurs multiniveaux modulaires (MMCs) connectés au réseau basse tension." Electronic Thesis or Diss., CY Cergy Paris Université, 2024. http://www.theses.fr/2024CYUN1301.
Full textThe modular multilevel converter (MMC) has emerged as one of the most promising topologies for medium- to high-voltage, high-power applications. Recently, it has also shown potential for applications requiring low voltages, known as mini MMCs, which contain a smaller number of submodules per arm. Key features of MMCs include modularity, voltage and power scalability, fault tolerance, transformer-less operation, and high-quality output waveforms. In recent years, numerous research studies have been conducted to address the technical challenges associated with MMC operation, control, and topology.One of the most significant applications for MMCs is in grid-connected systems. These converters offer the advantage of reducing current and voltage harmonics without the need for bulky passive components. Moreover, MMCs demonstrate reliability due to their structure, which enables them to continue operating even if one or more power switches fail. However, their control is complex due to the numerous switching configurations, necessitating sophisticated control algorithms. This thesis focuses on implementing advanced control techniques to enhance MMC performance. It aims to explore MMCs, improve existing power structures for novel applications, and increase efficiency and reliability through control design and modulation techniques. The research also investigates controlling MMCs using novel Model Predictive Control methods.Specifically, this thesis comprises a series of investigations addressing challenges and enhancing MMC performance across various applications. The first set of studies focuses on a new control design for MMCs, allowing separate control of capacitor voltages in the upper and lower arms. The research also targets single-phase MMCs, enabling control under unbalanced power conditions between the upper and lower arms. Additionally, the study addresses modulation and voltage balancing techniques. A new modulation technique, the Integral Modulation Technique, an advancement of the Nearest Level Modulation Technique, is introduced. A novel sorting algorithm is also proposed to enhance MMC efficiency by reducing the number of commutations per second for existing modulation techniques such as NLM, IM, and PWM.The research extends to fault-tolerant operation in three-phase MMCs, proposing a method that injects DC and frequency harmonic circulating currents to sustain operation in the event of a faulty arm. A significant contribution involves developing a single-horizon finite control set model predictive control (FCS-MPC) algorithm for single-phase MMCs, which outperforms traditional methods in terms of commutations, grid current waveform quality, and capacitor voltage variance. Six FCS-MPC algorithms for MMCs are introduced, offering insights into their performance compared to a classic cascaded control scheme. The thesis concludes with a novel configuration for a Cascaded H-Bridge (CHB) converter designed for renewable energy integration, demonstrating effectiveness through simulations.In summary, this thesis presents a comprehensive exploration of MMCs, addressing control challenges, fault tolerance, modulation techniques, and innovative configurations for renewable energy integration. The findings contribute to advancing MMC technologies in various applications