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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

Développement de chargeurs intégrés pour véhicules hybrides plug-in / Development of integrated chargers for plug-in hybrid vehicles

Marzouk, Mounir 08 October 2015 (has links)
Ces travaux de thèse consistent en la conception et la réalisation d’une chaîne de tractionintégrée pour véhicule hybride plug-in. L’étude s’oriente vers une solution de convertisseur mutualisé,dans l’objectif de partager la traction et les modes chargeurs de batteries, la structure en NPC à 3niveaux est retenue. Le chargeur monophasé se base une topologie de redresseur à MLI monophaséavec trois bras entrelacés, avec l’utilisation des enroulements du moteur pour le filtrage. En chargeurtriphasé nous adaptons la topologie pour réaliser un montage en double boost triphasé. Pour chaqueconfiguration, les passifs sont dimensionnés pour répondre aux contraintes en courant BF et HF. Lecontrôle adopté se base sur les correcteurs résonants. Enfin, un prototype de 5 kW a été réalisé pourvalider les différents modes de l’application.Dans une seconde partie, nous proposons une solution de chargeur isolé sans étage continu auprimaire à double ponts actifs (DAB). La topologie est modélisée au premier harmonique et unecommande assurant l’absorption sinusoïdale est étudiée. Une configuration isolée triphasée permetl’accès aux puissances plus élevées ainsi que la réduction des ondulations de courant BF en sortie. / This thesis consists on the design and realization of a plug-in hybrid vehicle integrated tractiondrive supply. The work turns to a solution of a mutualized converter, in the objective to imagine asolution which shared drive and battery chargers modes, the three-level NPC topology has beenretained. The single phase charger is based on an interleaved PWM rectifier, and motor windings areused as smoothing inductors. A double-boost PFC configuration is introduced to ensure the threephasecharger. Passives are sized in each configuration in order to take in account the whole currentconstraints (LF and HF). The PFC behavior is based on the resonant controllers. Then, a 5 kWprototype has been realized to validate the different application modes.In a second part, a single-stage isolated charger based on a Dual-Active-Bridge (DAB) isproposed. The topology is modeled to the fundamental and the PFC control law is studied. A threephaseconfiguration is simulated in order to achieve higher charging powers and to reduce batterycurrent low-frequency ripple.
32

Integração de filtro ativo de potência monofásico e bifásico ao sistema de propulsão de um veículo elétrico

Rodrigues, Márcio do Carmo Barbosa Poncilio 20 November 2014 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-07-21T14:26:57Z No. of bitstreams: 1 marciodocarmobarbosaponciliorodrigues.pdf: 24085481 bytes, checksum: a2ce2552f002816f01354d228d257f85 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-08-09T13:18:07Z (GMT) No. of bitstreams: 1 marciodocarmobarbosaponciliorodrigues.pdf: 24085481 bytes, checksum: a2ce2552f002816f01354d228d257f85 (MD5) / Made available in DSpace on 2017-08-09T13:18:07Z (GMT). No. of bitstreams: 1 marciodocarmobarbosaponciliorodrigues.pdf: 24085481 bytes, checksum: a2ce2552f002816f01354d228d257f85 (MD5) Previous issue date: 2014-11-20 / A gradativa substituição da atual frota de veículos de motor de combustão interna por veículos elétricos (VEs) pode ser vista como um importante fator para a melhoria das condições ambientais nos centros urbanos, uma vez que possibilita a redução das emissões de poluentes atmosféricos nocivos à saúde humana. Os conversores estáticos existentes no sistema de propulsão de veículos puramente elétricos e híbridos "plug-in" podem ser utilizados para funções adicionais, diferentes da tração elétrica. Com poucas adaptações nos circuitos eletrônicos do VE é possível integrar funções como recarga de baterias, geração distribuída de energia elétrica e compensação de reativos. Este tipo de aplicação é particularmente interessante no contexto de redes inteligentes de energia elétrica (smart grids). Esta integração de funcionalidades ao VE, além de permitir a redução de custos e economia de recursos naturais, poderá resultar em retorno financeiro aos proprietários destes veículos pela prestação de serviços auxiliares ao sistema elétrico. Neste trabalho é proposta a utilização de veículos elétricos na compensação de harmônicos de corrente e de potência reativa em instalações elétricas residenciais e comerciais, utilizando o próprio sistema de propulsão do VE para operar como filtro ativo de potência, o que pode ser realizado de forma simultânea à recarga do banco de baterias do VE ou durante seu uso como unidade de geração distribuída de ener-gia elétrica (operação no modo V2G, vehicle-to-grid). Sendo o padrão de conexão de VEs à rede de energia elétrica atualmente adotado pela maior parte dos fabricantes de automóveis elétricos baseado em alimentação monofásica (com possibilidade de alimen-tação bifásica), é explorada, neste trabalho, a utilização de um VE na compensação de cargas monofásicas e bifásicas, em condições típicas de instalações elétricas residenciais e comerciais, de forma compatível a tal padrão. A inclusão desta funcionalidade aos VEs pode contribuir para a redução do impacto da eletrificação veicular no sistema elétrico, pois com a diminuição do fluxo de potência reativa e harmônica na rede elé-trica, torna-se maior a sua capacidade disponível para transporte de potência ativa, facilitando o suprimento de energia a novas cargas (que podem ser os próprios VEs). / The gradual replacement of the current internal combustion engine vehicles by elec-tric vehicles (EVs) comes up as being an important factor to the improvement of urban centers environmental conditions, since it enables reduction on the emissions of atmo-spheric pollutants harmful to human health. Additional tasks, apart from traction, can be performed by battery and plug-in hybrid electric vehicle powertrain on-board power electronic converters. It is possible to integrate functions such as battery charge, electric distributed power generation and reactive power compensation with few modifications on the EV electronics circuitry. This kind of application is especially interesting under the context of smart grids. The integration of these additional functions to an electric vehicle is a very desirable feature, since it can result on cost reduction (in comparison to the separated implementation of the integrated functions) and revenue to the owner of the vehicle by providing ancillary services to the electric power system. This work proposes the application of electric vehicles on the compensation of cur-rent harmonic components and reactive power in residential and commercial electricity networks by means of the integration of a shunt active power filter (APF) into their powertrain electronics circuitry, which can simultaneously operate with the EV bat-tery pack charging or during its use as an electric distributed power generator unit (vehicle-to-grid, V2G, operation mode). Since the EV grid connection standard cur-rently adopted by electric automobiles manufacturers is based on a single-phase power supply system (with a possible two-phase power supply connection), this work focuses on the application of an electric vehicle in the compensation of single-phase and two-phase loads under residential and commercial electricity networks typical conditions, in order to meet the compliance to the requirements of such standard. The inclusion of this functionality to EVs can contribute on the reduction of vehicular electrification impact on the electric power system, since the decrease of reactive and harmonic power flow into the grid results in higher available capacity of active power flow in the power conductors, which allows to supply electricity to new electric loads (that can be the EVs themselves).
33

Záložní zdroj / Uninterruptible Power Supply

Mrázek, Petr January 2019 (has links)
The thesis deals with Uninterruptible Power Supply (UPS) and associated problems of backup power in case of unexpected outages of electricity. Start of work is dedicated to limitation of the electricity supplies, as well as their causes and consequences. Furthermore, brief history of UPS and subsequently distinguish between UPS’s architectures. There is also a description of the energy sources such as batteries, flywheels or fuel cells. Part of thesis describes security of electricity supply in health care facilities, including requirements for emergency power. The own design of UPS is described in the end.
34

Záložní zdroj (UPS) / Uninterruptible Power Supply

Mrázek, Petr January 2015 (has links)
The thesis deals with Uninterruptible Power Supply (UPS) and associated problems of backup power in case of unexpected outages of electricity. Start of work is dedicated to limitation of the electricity supplies, as well as their causes and consequences. Furthermore, brief history of UPS and subsequently distinguish between UPS’s architectures. There is also a description of the energy sources such as batteries, flywheels or fuel cells. Part of thesis describes security of electricity supply in health care facilities, including requirements for emergency power. The own design of UPS is described in the end.

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