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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.
131

Contribution à l'analyse de l'impact des véhicules électrifiés sur le réseau de distribution d'électricité. / Contribution to the analysis of the impact of electric vehicles on the electricity distribution grid

Gaonac'h, Thomas 28 September 2015 (has links)
Depuis quelques années de nombreux modèles de véhicules électriques et hybrides rechargeables sont disponibles à la vente. Les prévisions annoncent des niveaux de pénétration importants pour ces prochaines années. En effet, l’État français a annoncé deux millions de véhicules électrifiés pour 2020. Les véhicules électriques impactent les réseaux d’électricité en se rechargeant, c’est alors que les flux électriques dans les réseaux évoluent. Cette recharge qui induit un changement du dimensionnement du réseau est abordée dans ce manuscrit, qui s’attache à évaluer ce changement. De plus, avec le développement de la thématique des “smart grid”, les véhicules électrifiés peuvent avoir un intérêt pour la conduite du système électrique. Cette étude a pour objectif s’attachera aussi à tenter de déterminer l’équilibre entre intérêts des véhicules électrifiés dans ce contexte et difficultés (sous la forme de coûts) qu’ils pourraient rencontrer s’ils participaient à la conduite du système.L’impact des véhicules électrifiés se concentre principalement sur les réseaux de distribution d’électricité. Dans les réseaux de distribution d’électricité, les lignes et les câbles sont des infrastructures indispensables. Alors que de nombreuses études s’intéressent au dimensionnement des transformateurs du réseau d’électricité, peu d’entre elles analysent les lignes et les câbles du réseau. Une volonté de combler ce manque est alors apparue. Ce manuscrit traite la problématique du dimensionnement des conducteurs, des lignes et des câbles du réseau de distribution d’électricité. Les véhicules électrifiés peuvent également être utilisés comme moyen de stockage de l’électricité, afin d’améliorer la conduite des réseaux d’électricité. L’étude s’intéresse également à l’évaluation de l’impact sur les conducteurs de l’utilisation des véhicules électriques et hybrides rechargeables comme moyen de stockage (donc comme moyen de conduite du système). / In recent years many models of electric and plug-in hybrid vehicles are available for sale. The forecasts predict high levels of penetration in the coming years. Indeed, the French government announced two million electric vehicles by 2020. Electric vehicles impact the electric grid by recharging, changing electricity flows in the grid. Electric vehicles charging changes the manner of sizing the grid which is the topic of this manuscript. Moreover, with the development of the smart grids, electric vehicles may have an interest as actor of the electrical system. This study also focuses on trying to determine the balance between interests of electrified vehicles in this context and challenges (in the form of costs) they might encounter if they are involved in the operation of the electric system.The impact of electric vehicles mainly focuses on the distribution grid lines and cables are a major infrastructure of the distribution grid. While many studies focus on electric transformers sizing, few of them analyze the lines and cables of the grid. A desire to fill that gap then appeared. This manuscript deals with the problem of sizing lines' and cables' conductors of the electric distribution grid. Electric vehicles can also be used as electricity storage device to improve the operation of electricity networks. The study also assesses the impact on grid conductors of electric vehicles use for storage (i.e. as a means for operating the system).
132

Aplicação de redes inteligentes nas instalações elétricas residenciais / Application of smart grid in residential electrical installations.

Caires, Luis Eduardo 11 April 2012 (has links)
A eletricidade como recurso energético adquiriu importância vital na sociedade moderna, pois permite atender de modo relativamente simples a demanda pelos seus serviços. Dessa forma a demanda pela eletricidade aumenta proporcionalmente a evolução das populações que dela se beneficiam. O sistema elétrico que produz esse insumo está limitado em sua capacidade aos recursos disponíveis para geração, transmissão e distribuição de energia. Grosso modo esse limite é definido pela potência máxima do sistema. Essa potência máxima pode ser alcançada em determinados períodos do dia, denominados horários de ponta e em boa parte do tempo o sistema é sub aproveitado. Havendo a possibilidade de controle da demanda, seria possível empregar essa capacidade ociosa pela transferência de cargas para horários mais favoráveis. Para isso é necessário haver a ação coordenada dos muitos consumidores para obter o resultado operacional desejado. A coordenação seria então obtida através das chamadas redes inteligentes que agregam funções e automação com vários níveis de complexidade e constituem um sistema muito amplo que une a geração ao consumo. A diferença perceptível pelo consumidor residencial está no fato deste ser incluído na operação dessa rede praticamente em tempo real, ou seja, espera-se sua participação mais efetiva no sistema elétrico. Um dos meios projetados para obter esse efeito é através de incentivos tarifários, onde a variação do custo da energia motivaria o consumidor a mudar seus hábitos de consumo. Para participar desse sistema o consumidor residencial precisa adaptar suas instalações para operar de modo mais eficiente obtendo o máximo de energia com o menor custo. Não é sempre que a mudança de hábitos está no poder do consumidor, de modo que este precisa de meios para adaptar suas instalações elétricas a essa realidade. A adaptação envolve incorporar meios de armazenamento e gerenciamento de recursos energéticos a fim de que a instalação forneça os serviços energéticos no momento em que é necessário, independente do momento em que adquire os insumos necessários. Para isso é necessário, além dos meios de armazenamento de energia, um sistema autônomo de controle, posto que os consumidores residenciais não devem viver em função de suas instalações elétricas. Esse sistema autônomo seria composto por elementos automáticos derivados daqueles empregados na automação industrial nos circuitos de comandos elétricos. Dessa forma o objetivo deste trabalho é analisar o potencial de aplicação dos chamados dispositivos elétricos inteligentes (medidores e elementos de controle) na automação das instalações elétricas residenciais e sua possível interação com as redes inteligentes. / Electricity as an energy resource acquired vital importance in modern society because it allows relatively easily meet the demand for their services. Thus the demand for electricity increases with the evolution of populations who benefit from. The electrical system that produces this input is limited in its ability to available resources for generation, transmission and distribution. Roughly speaking this limit is set by the maximum power of the system. This maximum power can be achieved at certain times of the day, called peak hours and in most of the time the system is under utilized. Having the ability to control demand, you could use that excess capacity by transferring loads to more favorable times. For this there must be a coordinated action of many consumers to obtain operating results. Coordination would then be obtained through socalled smart grids that add functions and automation with various levels of complexity and constitute a very large system that binds generation to consumption. The noticeable difference is in the residential consumer of this fact be included in the operation of this network in near real time, or is awaiting more effective participation in the electrical system. One of the means designed to achieve this effect is through tariff incentives, where the variation of the energy cost would motivate consumers to change their consumption habits. To participate in this system the residential consumer needs to adapt its facilities to operate more efficiently by getting the maximum power at the lowest cost. It is not often that changing habits is the power of consumer, so it needs the means to adapt their electrical installations to this reality. Adaptation involves incorporating means for storing and managing energy resources so that the installation provides energy services at the time that is required, regardless of the time it purchases the necessary inputs. This requires, beyond the means of energy storage, as a control, given that residential consumers should not live according to their electrical out lets. This system would consist of standalone automatic elements derived from those used in industrial automation electrical control circuits. Therefore the aim of this work is to analyze the potential application of so-called smart electric devices (meters and control elements) in the automation of residential electrical installations and their interaction with the smart grid.
133

Voltage control in distribution networks using on-load tap changer transformers

Gao, Chao January 2013 (has links)
Voltage is one of the most important parameters for electrical power networks. The Distribution Network Operators (DNOs) have the responsibility to maintain the voltage supplied to consumers within statutory limits. On-Load Tap Changer (OLTC) transformer equipped with Automatic Voltage Control (AVC) relay is the most widely used and effective voltage control device. Due to a variety of advantages of adding Distributed Generation (DG), more and more distributed resources are connected to local distribution networks to solve constraints of networks, reduce the losses from power supply station to consumers. When DG is connected, the direction of power flow can be reversed when the DG output power exceeds the local load. This means that the bidirectional power flow can either be from power grid towards loads, or vice versa. The connection point of DG may suffer overvoltage when the DG is producing a large amount of apparent power. The intermittent nature of renewable energy resources which are most frequently used in DG technology results in uncertainty of distribution network operation. Overall, conventional OLTC voltage control methods need to be changed when DG is connected to distribution networks. The required voltage control needs to address challenges outlined above and new control method need to be formulated to reduce the limitations of DG output restricted by current operational policies by DNOs. The thesis presents an analysis of voltage control using OLTC transformer with DG in distribution networks. The thesis reviews conventional OLTC voltage control schemes and existing policies of DNOs in the UK. An overview of DG technologies is also presented with their operation characteristics based on power output. The impact of DG on OLTC voltage control schemes in distribution networks is simulated and discussed. The effects of different X/R ratio of overhead line and underground cable are also considered. These impacts need to be critically assessed before any new method implementation. The thesis also introduces the new concepts of Smart Grid and Smart Meter in terms of the transition from passive to active distribution networks. The role of Smart Meter and an overview of communication technologies that could be used for voltage control are investigated. The thesis analyses the high latency of an example solution of which cost and availability are considered to demonstrate the real-time voltage control using Smart Metering with existing communication infrastructures cannot be achieved cost-effectively. The thesis provides an advanced compensation-based OLTC voltage control algorithm using Automatic Compensation Voltage Control (ACVC) technique to improve the voltage control performance with DG penetration without communication. The proposed algorithm is simulated under varying load and DG conditions based on Simulink MATLAB to show the robustness of the proposed method. A generic 11kV network in the UK is modelled to evaluate the correct control performance of the advanced voltage control algorithm while increasing the DG capacity.
134

Bases conceituais da implantação de redes elétricas inteligentes de distribuição de energia elétrica. / Conceptual basis for implementation of distribution smart grids.

Cunha, Antonio Paulo da 18 May 2011 (has links)
As redes elétricas inteligentes significam um novo paradigma de fornecimento de energia, cuja concepção integra várias áreas de concentração, novas funcionalidades e funções até então não realizáveis, bem como uma pluralidade de tecnologias e a necessidade de infraestrutura de apoio para a sua realização. A transição das redes elétricas atuais para o modelo de rede inteligente constitui-se num processo complexo, que envolve aspectos técnicos, econômicos, regulatórios e sociológicos. Esta pesquisa visa contribuir significativamente para a solução dessa questão pela proposição das bases conceituais para realizar efetivamente um plano de implementação, respeitando condições vigentes e impostas por cenários de outros setores. O modelo proposto, centrado na expansão da automação, lança as bases para a análise dos impactos da rede elétrica inteligente, para a formulação, análise e seleção de alternativas de implementação. É introduzido o conceito e forma de avaliação de uma rede por meio da definição de um índice de inteligência de uma rede elétrica, composto de vários indicadores, de forma a expressar padrões de eficiência energética e operativa, aspectos de gestão de ativos e da qualidade do serviço. A proposta de alternativas para evolução da automação se baseia em um conjunto de funções pré-estabelecidas, que melhoram os indicadores de desempenho e apresentam custos e benefícios quantificáveis. / The smart grids mean a new paragon for energy supply, whose concept integrates several areas of concentration, functionalities and functions non achievable up to now, as well as a plurality of technologies and the need of supporting infrastructure for its accomplishment. The transition of the present electrical networks to the smart grid model constitutes a complex process, which involves technical, economical, regulatory and sociological aspects. This research aims to contribute significantly to the solution of this issue by proposing the conceptual basis for effectively perform an implementation plan taking into account the constraints imposed by scenarios from other sectors. The proposed model, focused in automation expansion, launches the basis for the impact analysis of Smart Grid in order to formulate, analyze and selection alternatives of implementation. The concept and evaluation method of grid through the definition of a grid intelligence index, composed by several indicators is introduced in order to express standards of energy and operational efficiency, asset management and quality of supply. The proposal of alternatives for automation evolution is based on a set of pre established functions, which improve the performance indicators and present valuable costs and benefits.
135

Techno-economic and environmental assessment of a smart multi-energy grid

Zhang, Lingxi January 2018 (has links)
This PhD thesis proposes a bottom-up approach that accurately addresses the operational flexibility embedded in each part of a multi-energy system (MES). Several models which cover the simulations from replicating domestic electrified demands to power system scheduling are proposed. More specifically, a domes-tic multi-energy consumption model is firstly developed to simulate one minute resolution energy profiles of individual dwellings with the installation of prospec-tive technologies (i.e., electric heat pumps (EHPs), electric vehicles (EVs)). After-wards, a fast linear programming (LP) unit commitment (UC) model is devel-oped with the consideration of characteristics of generators and a full set of ancil-lary services (i.e., frequency response and reserves). More importantly, the fre-quency response requirements in low inertia systems are assessed with the con-sideration of three grid frequency regulations (i.e., rate of change of frequency, Nadir and quasi-steady state). Furthermore, the UC model has integrated vari-ous flexibility contributors in MES to provide ancillary and flexibility services, which include pumped hydro storages (PHSs), interconnectors, batteries and demand side resources (i.e., individual EHPs, heat networks, electrolysers). More importantly, the fast frequency response (FFR) provision from nonsynchronous resources is implemented and the demand response application of electrolysers is taken as an example to provide FFR in the UC model. By using the integrated UC model with the consideration of flexibility services provided by resources in the MES, the advantages of multi-energy operation can be clearly identified which can be used to inform system operators and policy makers to design and operate energy systems in a more economic and environment-friendly way.
136

Gerenciamento de elasticidade em computação em nuvem : estudo de caso usando Smart Grid

Simões, Rhodney Arthur Barreto Koning January 2013 (has links)
Orientador: Carlos Alberto Kamienski / Dissertação (mestrado) - Universidade Federal do ABC. Programa de Programa de Pós-Graduação em Engenharia da Informação, 2013
137

Aplicação de redes inteligentes nas instalações elétricas residenciais / Application of smart grid in residential electrical installations.

Luis Eduardo Caires 11 April 2012 (has links)
A eletricidade como recurso energético adquiriu importância vital na sociedade moderna, pois permite atender de modo relativamente simples a demanda pelos seus serviços. Dessa forma a demanda pela eletricidade aumenta proporcionalmente a evolução das populações que dela se beneficiam. O sistema elétrico que produz esse insumo está limitado em sua capacidade aos recursos disponíveis para geração, transmissão e distribuição de energia. Grosso modo esse limite é definido pela potência máxima do sistema. Essa potência máxima pode ser alcançada em determinados períodos do dia, denominados horários de ponta e em boa parte do tempo o sistema é sub aproveitado. Havendo a possibilidade de controle da demanda, seria possível empregar essa capacidade ociosa pela transferência de cargas para horários mais favoráveis. Para isso é necessário haver a ação coordenada dos muitos consumidores para obter o resultado operacional desejado. A coordenação seria então obtida através das chamadas redes inteligentes que agregam funções e automação com vários níveis de complexidade e constituem um sistema muito amplo que une a geração ao consumo. A diferença perceptível pelo consumidor residencial está no fato deste ser incluído na operação dessa rede praticamente em tempo real, ou seja, espera-se sua participação mais efetiva no sistema elétrico. Um dos meios projetados para obter esse efeito é através de incentivos tarifários, onde a variação do custo da energia motivaria o consumidor a mudar seus hábitos de consumo. Para participar desse sistema o consumidor residencial precisa adaptar suas instalações para operar de modo mais eficiente obtendo o máximo de energia com o menor custo. Não é sempre que a mudança de hábitos está no poder do consumidor, de modo que este precisa de meios para adaptar suas instalações elétricas a essa realidade. A adaptação envolve incorporar meios de armazenamento e gerenciamento de recursos energéticos a fim de que a instalação forneça os serviços energéticos no momento em que é necessário, independente do momento em que adquire os insumos necessários. Para isso é necessário, além dos meios de armazenamento de energia, um sistema autônomo de controle, posto que os consumidores residenciais não devem viver em função de suas instalações elétricas. Esse sistema autônomo seria composto por elementos automáticos derivados daqueles empregados na automação industrial nos circuitos de comandos elétricos. Dessa forma o objetivo deste trabalho é analisar o potencial de aplicação dos chamados dispositivos elétricos inteligentes (medidores e elementos de controle) na automação das instalações elétricas residenciais e sua possível interação com as redes inteligentes. / Electricity as an energy resource acquired vital importance in modern society because it allows relatively easily meet the demand for their services. Thus the demand for electricity increases with the evolution of populations who benefit from. The electrical system that produces this input is limited in its ability to available resources for generation, transmission and distribution. Roughly speaking this limit is set by the maximum power of the system. This maximum power can be achieved at certain times of the day, called peak hours and in most of the time the system is under utilized. Having the ability to control demand, you could use that excess capacity by transferring loads to more favorable times. For this there must be a coordinated action of many consumers to obtain operating results. Coordination would then be obtained through socalled smart grids that add functions and automation with various levels of complexity and constitute a very large system that binds generation to consumption. The noticeable difference is in the residential consumer of this fact be included in the operation of this network in near real time, or is awaiting more effective participation in the electrical system. One of the means designed to achieve this effect is through tariff incentives, where the variation of the energy cost would motivate consumers to change their consumption habits. To participate in this system the residential consumer needs to adapt its facilities to operate more efficiently by getting the maximum power at the lowest cost. It is not often that changing habits is the power of consumer, so it needs the means to adapt their electrical installations to this reality. Adaptation involves incorporating means for storing and managing energy resources so that the installation provides energy services at the time that is required, regardless of the time it purchases the necessary inputs. This requires, beyond the means of energy storage, as a control, given that residential consumers should not live according to their electrical out lets. This system would consist of standalone automatic elements derived from those used in industrial automation electrical control circuits. Therefore the aim of this work is to analyze the potential application of so-called smart electric devices (meters and control elements) in the automation of residential electrical installations and their interaction with the smart grid.
138

Bases conceituais da implantação de redes elétricas inteligentes de distribuição de energia elétrica. / Conceptual basis for implementation of distribution smart grids.

Antonio Paulo da Cunha 18 May 2011 (has links)
As redes elétricas inteligentes significam um novo paradigma de fornecimento de energia, cuja concepção integra várias áreas de concentração, novas funcionalidades e funções até então não realizáveis, bem como uma pluralidade de tecnologias e a necessidade de infraestrutura de apoio para a sua realização. A transição das redes elétricas atuais para o modelo de rede inteligente constitui-se num processo complexo, que envolve aspectos técnicos, econômicos, regulatórios e sociológicos. Esta pesquisa visa contribuir significativamente para a solução dessa questão pela proposição das bases conceituais para realizar efetivamente um plano de implementação, respeitando condições vigentes e impostas por cenários de outros setores. O modelo proposto, centrado na expansão da automação, lança as bases para a análise dos impactos da rede elétrica inteligente, para a formulação, análise e seleção de alternativas de implementação. É introduzido o conceito e forma de avaliação de uma rede por meio da definição de um índice de inteligência de uma rede elétrica, composto de vários indicadores, de forma a expressar padrões de eficiência energética e operativa, aspectos de gestão de ativos e da qualidade do serviço. A proposta de alternativas para evolução da automação se baseia em um conjunto de funções pré-estabelecidas, que melhoram os indicadores de desempenho e apresentam custos e benefícios quantificáveis. / The smart grids mean a new paragon for energy supply, whose concept integrates several areas of concentration, functionalities and functions non achievable up to now, as well as a plurality of technologies and the need of supporting infrastructure for its accomplishment. The transition of the present electrical networks to the smart grid model constitutes a complex process, which involves technical, economical, regulatory and sociological aspects. This research aims to contribute significantly to the solution of this issue by proposing the conceptual basis for effectively perform an implementation plan taking into account the constraints imposed by scenarios from other sectors. The proposed model, focused in automation expansion, launches the basis for the impact analysis of Smart Grid in order to formulate, analyze and selection alternatives of implementation. The concept and evaluation method of grid through the definition of a grid intelligence index, composed by several indicators is introduced in order to express standards of energy and operational efficiency, asset management and quality of supply. The proposal of alternatives for automation evolution is based on a set of pre established functions, which improve the performance indicators and present valuable costs and benefits.
139

Computer aided design of 3D of renewable energy platform for Togo's smart grid power system infrastructure

Komlanvi, Moglo January 2018 (has links)
The global requirement for sustainable energy provision will become increasingly important over the next fifty years as the environmental effects of fossil fuel use become apparent. Therefore, the issues surrounding integration of renewable energy supplies need to be considered carefully. The focus of this work was the development of an innovative computer aided design of a 3 Dimensional renewable energy platform for Togo’s smart grid power system infrastructure. It demonstrates its validation for industrial, commercial and domestic applications. The Wind, Hydro, and PV system forming our 3 Dimensional renewable energy power generation systems introduces a new path for hybrid systems which extends the system capacities to include, a stable and constant clean energy supply, a reduced harmonic distortion, and an improved power system efficiency. Issues requiring consideration in high percentage renewable energy systems therefore includes the reliability of the supply when intermittent sources of electricity are being used, and the subsequent necessity for storage and back-up generation The adoption of Genetic algorithms in this case was much suited in minimizing the THD as the adoption of the CHB-MLI was ideal for connecting renewable energy sources with an AC grid. Cascaded inverters have also been proposed for use as the main traction drive in electric vehicles, where several batteries or ultra-capacitors are well suited to serve as separate DC sources. The simulation done in various non-linear load conditions showed the proportionality of an integral control based compensating cascaded passive filter thereby balancing the system even in non-linear load conditions. The measured total harmonic distortion of the source currents was found to be 2.36% thereby in compliance with IEEE 519-1992 and IEC 61000-3 standards for harmonics This work has succeeded in developing a more complete tool for analysing the feasibility of integrated renewable energy systems. This will allow informed decisions to be made about the technical feasibility of supply mix and control strategies, plant type, sizing and storage sizing, for any given area and range of supply options. The developed 3D renewable energy platform was examined and evaluated using CAD software analysis and a laboratory base mini test. The initial results showed improvements compared to other hybrid systems and their existing control systems. There was a notable improvement in the dynamic load demand and response, stability of the system with a reduced harmonic distortion. The derivatives of this research therefore proposes an innovative solution and a path for Togo and its intention of switching to renewable energy especially for its smart grid power system infrastructure. It demonstrates its validation for industrial, commercial and domestic applications.
140

Napredni distributivni menadžment sistem zasnovan na Cloud infrastrukturi / Cloud Infrastructure-based Advanced Distribution Management System

Popović Nemanja 24 May 2018 (has links)
<p>U ovoj doktorskoj disertaciji ispitana je mogućnost prebacivanja Naprednog Distributivnog Menadžment Sistema (NDMS) zasnovanog na zajedničkoj operaciono tehnološkoj platformi na virtualno Cloud infrastrukturno okruženje. Prvo je odabrano tradicionalno NDMS rešenje zasnovano na fizičkoj računarskoj arhitekturi i identifikovani su funkcionalni blokovi. Zatim su profilirane njihove performanse prema četiri ključna resursa: procesor, operativna memorija, računarska mreža i stalna memorija. Dalje predloženo je virtualno rešenje zasnovano na Cloud infrastrukturi koje je verifikovano na dve zamišljene elektrodistributivne mreže realnih veličina (maloj i velikoj) i u dva testna scenarija (stabilnog stanja i visoke aktivnosti). Na kraju predstavljeni su rezultati testiranja koji pokazaju da se NDMS može prebaciti u virtualno Cloud okruženje bez negativnog uticaja na funkcionalne i nefunkcionalne zahteve NDMS rešenja.</p> / <p>This dissertation inspects the possibility of transferring the Advanced Distribution Management System (ADMS) based on a common operating technology platform to the virtual Cloud Infrastructure Environment. First, a traditional ADMS solution based on physical computing architecture was chosen and functional blocks were identified. Furthermore, their performances were profiled to four key resources: processor, operating memory, computer network, and storage. Then, virtual cloud-based solution was proposed based on Cloud infrastructure which is verified on two imaginary power distribution networks of real size (small and large) and in two test scenarios (steady state and high activity). Finally, the test results show that ADMS can be transferred to a virtual Cloud environment without adversely affecting the functional and non-functional requirements of the ADMS solution.</p>

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