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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.
51

Rotational motion of pendula systems for wave energy extraction

Horton, Bryan. January 2009 (has links)
Thesis (Ph.D.)--Aberdeen University, 2009. / Title from web page (viewed on July, 1 2009). Includes bibliographical references.
52

Modelagem completa e análise dos recursos energéticos do lado da demanda para o PIR. / Modelling and assessment of demand side energy resources in the integrated resources planning process.

Ricardo Lacerda Baitelo 02 March 2006 (has links)
Esta dissertação propõe um modelo de caracterização de recursos energéticos do lado da demanda que pretende abranger todos os tipos de ações e medidas referentes ao gerenciamento da demanda e à conservação energética, avaliando-as de forma holística, dentro de quatro dimensões: técnico-econômica, ambiental, social e política. Os recursos considerados na composição do modelo são submetidos às fases de Inventário de Recursos Energéticos do Lado da Demanda, Caracterização das Dimensões e Atributos de Avaliação de Recursos, Formulação dos Potenciais Energéticos e Aplicação do Modelo em Caso Piloto. O Inventário de Recursos Energéticos do Lado da Demanda pretende levantar, descrever e segmentar todas as alternativas energéticas de GLD e setores de consumo energético. A Caracterização da Avaliação de Recursos delimita as esferas de análise de recursos e a caracterização de seus atributos quanto a custos e benefícios provenientes de seu emprego. A Formulação dos Potenciais Energéticos define seu cálculo a partir de sua amplitude e restrições gerais de aplicação. O modelo é aplicado em um estudo piloto, na Região Administrativa de Araçatuba, por meio de um exercício de formulação do PIR, considerando a utilização de ferramentas de Avaliação dos Custos Completos, Cálculo de Potenciais Energéticos e Elaboração de Cenários de Projeção do Consumo Energético para um horizonte de tempo determinado. / This work presents a model for the characterization and assessment of demand side energy resources, which intends to comprehend every kind of action or measure related to demand side management and energy conservation, evaluated thouroughly into four dimensions: technical-economical, environmental, social and political. The resources included in the composition of the model are subjected to the stages of Inventary of Demand Side Resources, Characterization of Dimensions and Attributes of the Resources Assessment, Formulation of Energy Potentials and Model Application on a Real Case Study. The Inventary of Demand Side Resources intends to enlist, describe and segment all demand side management energy alternatives and their application in different economy sectors. The Characterization of the Resources Assessment defines the spheres of the assessment of resources and the characterization of its attributes as for costs and benefits resulting from their utilization. The Formulation of Energy Potentials defines their accounting based on their range and general application restrictions. The Model is applied in a case study, in the Administrative Region of Araçatuba, through an exercise of IRP formulation, regarding the utilization of Full Cost Accounting, Energy Potentials Accounting and Scenarios of Energy Consumption for a determined horizon.
53

A hybrid energy system based on renewable energy for the electrification of low-income rural communities

Gaslac, Lucero, Willis, Sebastian, Quispe, Grimaldo, Raymundo, Carlos 07 1900 (has links)
Electrification of low-income rural areas that have a limited connection or no access to electrical grids is one of the most demanding challenges in developing countries such as Peru. The international commitment to stop global warming and the reduction in the cost of renewable sources of energy have reduced the prices of fossil fuels in some cases. This has opened the way to the current research which proposes a hybrid energy system (HES) based on the use of renewable sources of energy. Therefore, a renewable electricity system (HRES) was set up at the village of Monte-Catache in the Cajamarca region, which is one of the poorest areas of Peru. Surveys and field studies were used to evaluate the socioeconomic characteristics, availability of renewable energy resources, and energy demand of this region. Potential energy sources were evaluated, and isolated photovoltaic systems with a battery bank were found to be the most appropriate according to the results obtained in the simulation with HOMER. This proposal constitutes an interesting contribution for future energy solutions in isolated and low-income rural areas. / Revisión por pares
54

Reliability and risk analysis of post fault capacity services in smart distribution networks

Syrri, Angeliki Lydia Antonia January 2017 (has links)
Recent technological developments are bringing about substantial changes that are converting traditional distribution networks into "smart" distribution networks. In particular, it is possible to observe seamless integration of Information and Communication Technologies (ICTs), including the widespread installation of automatic equipment, smart meters, etc. The increased automation facilitates active network management, interaction between market actors and demand side participation. If we also consider the increasing penetration of distributed generation, renewables and various emerging technologies such as storage and dynamic rating, it can be argued that the capacity of distribution networks should not only depend on conventional asset. In this context, taking into account uncertain load growth and ageing infrastructure, which trigger network investments, the above-mentioned advancements could alter and be used to improve the network design philosophy adopted so far. Hitherto, in fact, networks have been planned according to deterministic and conservative standards, being typically underutilised, in order for capacity to be available during emergencies. This practice could be replaced by a corrective philosophy, where existing infrastructure could be fully unlocked for normal conditions and distributed energy resources could be used for post fault capacity services. Nonetheless, to thoroughly evaluate the contribution of the resources and also to properly model emergency conditions, a probabilistic analysis should be carried out, which captures the stochasticity of some technologies, the randomness of faults and, thus, the risk profile of smart distribution networks. The research work in this thesis proposes a variety of post fault capacity services to increase distribution network utilisation but also to provide reliability support during emergency conditions. In particular, a demand response (DR) scheme is proposed where DR customers are optimally disconnected during contingencies from the operator depending on their cost of interruption. Additionally, time-limited thermal ratings have been used to increase network utilisation and support higher loading levels. Besides that, a collaborative operation of wind farms and electrical energy storage is proposed and evaluated, and their capacity contribution is calculated through the effective load carrying capability. Furthermore, the microgrid concept is examined, where multi-generation technologies collaborate to provide capacity services to internal customers but also to the remaining network. Finally, a distributed software infrastructure is examined which could be effectively used to support services in smart grids. The underlying framework for the reliability analysis is based on Sequential Monte Carlo Simulations, capturing inter-temporal constraints of the resources (payback effects, dynamic rating, DR profile, storage remaining available capacity) and the stochasticity of electrical and ICT equipment. The comprehensive distribution network reliability analysis includes network reconfiguration, restoration process, and ac power flow calculations, supporting a full risk analysis and building the risk profile for the arising smart distribution networks. Real case studies from ongoing project in England North West demonstrate the concepts and tools developed and provide noteworthy conclusions to network planners, including to inform design of DR contracts.
55

Localização de faltas para sistemas de distribuição ativos : metodologia analítica adaptativa baseada na estimativa da impedância aparente

Orozco-Henao, Cesar Augusto January 2016 (has links)
Este documento apresenta uma metodologia analítica adaptativa para localização de faltas baseada na estimativa da impedância para sistemas de distribuição ativos. A metodologia proposta combina a informação fornecida por dispositivos eletrônicos inteligentes alocados na subestação principal e nos terminais de cada unidade de Recurso Energético Distribuído (do inglês Distributed Energy Resources - DER), o conhecimento da topologia da rede e os seus parâmetros para estimar a localização da falta. A característica adaptativa é dada pelo uso de modelos elétricos lineares para considerar o efeito das DER conectadas à rede, quando a informação fornecida pelos Dispositivos Eletrônicos Inteligentes (do inglês Intelligent Electronic Devices - IED) não é disponível. Adicionalmente, uma estratégia baseada na técnica Ladder é desenvolvida para estimar a contribuição de corrente desde as DER até o ponto de falta. Esta estratégia permite considerar vários geradores conectados e seus diferentes modos de operação. A metodologia proposta foi validada com o sistema IEEE 34 barras. Este sistema foi modelado no Alternative Transients Program (ATP) e modificado pela inserção de várias unidades DER. A metodologia proposta foi validada em vários cenários. Estes cenários avaliam o efeito da distância até a falta, resistência da falta, incerteza na carga, nível de penetração de DER, número de geradores conectados e erros nas medidas ou na estimação dos parâmetros das DER quando seus modelos forem utilizados. Para estas considerações, o desempenho da formulação proposta é satisfatório, apresentando erros menores do que 3%. / This document presents an adaptive analytical impedance-based fault location methodology for active distribution systems. The proposal combines information provided by Intelligent Electronic Devices (IEDs) located in the substation, each Distributed Energy Resources units terminal, the knowledge of the network topology as well as its parameters to estimate the fault location. Its adaptive feature is given by the use of linear analytical equivalent models to consider of DER effect in case the information provided by a local IED is not available. Additionally, a ladder-based technique is proposed to estimate the current contribution from of DER to the fault point. This process allows considering several DER connected and their different operation modes. The proposed methodology is validated on the IEEE 34-node test feeder. This system is modeled on ATP/EMTP and modified with the insertion of several DER units. The methodology is validated by considering several scenarios. These scenarios evaluate the effect of fault distance, fault resistance, load variation, DER penetration level, numbers of DERs connected and errors in the DER parameters. For these considerations, the proposed methodology performance is satisfactory, presenting fault location errors below 3%.
56

Recursos energéticos e política exterior nos governos de Lula da Silva (2003-2010) /

Canesin, Ronaldo Montesano January 2018 (has links)
Orientador: Shiguenoli Miyamoto / Resumo: Nesta dissertação analisa-se a política exterior do Brasil na área de energia nos mandatos presidenciais de Lula da Silva. A questão energética é algo estratégico a todos os Estados e tem condicionado a moldagem do Sistema Internacional e a distribuição de poder desde, pelo menos, a Primeira Revolução Industrial. A busca por segurança energética tem sido um objetivo constante de países com déficit em sua produção de energia. A solução desta questão pode ser tanto doméstica, quanto oriunda da política exterior. A situação energética brasileira encontra-se em déficit, indicando que o país deva agir para garantir seu abastecimento de energia. Enquanto esta força exerce seu papel perene sobre as ações estatais, existiu também a concepção de Cooperação Sul-Sul como incentivo poderoso à atuação diplomática brasileira no âmbito externo, durante o período analisado. O objetivo geral deste trabalho é identificar qual o eixo norteador da atuação diplomática brasileira nos governos de Lula da Silva, se ele for existente. A hipótese norteadora é a de que a diplomacia brasileira focou sua atuação através do prisma da Cooperação Sul-Sul. Os principais materiais empíricos utilizados foram as séries históricas do Balanço Energético Nacional e os Atos Internacionais, recolhidos da plataforma online oficial do MRE (Concórdia). Por fim, os resultados da pesquisa são de duas naturezas, a identificação dos incentivos produzidos pela matriz energética nacional à ação diplomática brasileira e a exp... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This dissertation analyses Brazilian foreign policy in the energy field during Lula da Silva’s presidential terms. Energy is a strategic issue to every state and has been conditioning the International System framework and the power distribution at least since the First Industrial Revolution. The search for energy security has been a constant objective for states with deficits in their energy production. The solution for this issue might be both domestic and a foreign policy result. Brazilian energy status shows a deficit, which indicates it will act in order to ensure its energy supply. While this force applies its imperatives to all state actions, there was also the South-South Cooperation as a powerful incentive to the Brazilian diplomatic operation in the foreign sphere during the analyzed period. The main objective of this text is to identify what was the Brazilian diplomatic operation’s guiding line, if there is one. The main hypothesis is that Brazilian diplomacy was mainly guided by the South-South Cooperation axis. The main empiric materials were the National Energy Balance’s historical series and the International Acts, collected in the MRE’s official online platform (Concórdia). Lastly, our research results are twofold, the identification of incentives produced by the national energy matrix to the diplomatic operation and the exposition of some patterns in the Brazilian diplomatic International Acts to the energy field. / Mestre
57

Recursos energéticos e política exterior nos governos de Lula da Silva (2003-2010) / Energy resources and foreign policy in the Lula da Silva's presidency (2003-2010)

Canesin, Ronaldo Montesano [UNESP] 27 April 2018 (has links)
Submitted by Ronaldo Montesano Canesin (ronaldo.mcanesin@gmail.com) on 2018-05-18T15:47:41Z No. of bitstreams: 1 Dissertação RI.pdf: 1543877 bytes, checksum: 289ebb3784137e7f764daab4e6471c31 (MD5) / Approved for entry into archive by Janaina Celoto Guerrero de Mendonça (jcguerrero@marilia.unesp.br) on 2018-05-21T18:30:51Z (GMT) No. of bitstreams: 1 canesin_rm_me_mar.pdf: 1543877 bytes, checksum: 289ebb3784137e7f764daab4e6471c31 (MD5) / Made available in DSpace on 2018-05-21T18:30:51Z (GMT). No. of bitstreams: 1 canesin_rm_me_mar.pdf: 1543877 bytes, checksum: 289ebb3784137e7f764daab4e6471c31 (MD5) Previous issue date: 2018-04-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Nesta dissertação analisa-se a política exterior do Brasil na área de energia nos mandatos presidenciais de Lula da Silva. A questão energética é algo estratégico a todos os Estados e tem condicionado a moldagem do Sistema Internacional e a distribuição de poder desde, pelo menos, a Primeira Revolução Industrial. A busca por segurança energética tem sido um objetivo constante de países com déficit em sua produção de energia. A solução desta questão pode ser tanto doméstica, quanto oriunda da política exterior. A situação energética brasileira encontra-se em déficit, indicando que o país deva agir para garantir seu abastecimento de energia. Enquanto esta força exerce seu papel perene sobre as ações estatais, existiu também a concepção de Cooperação Sul-Sul como incentivo poderoso à atuação diplomática brasileira no âmbito externo, durante o período analisado. O objetivo geral deste trabalho é identificar qual o eixo norteador da atuação diplomática brasileira nos governos de Lula da Silva, se ele for existente. A hipótese norteadora é a de que a diplomacia brasileira focou sua atuação através do prisma da Cooperação Sul-Sul. Os principais materiais empíricos utilizados foram as séries históricas do Balanço Energético Nacional e os Atos Internacionais, recolhidos da plataforma online oficial do MRE (Concórdia). Por fim, os resultados da pesquisa são de duas naturezas, a identificação dos incentivos produzidos pela matriz energética nacional à ação diplomática brasileira e a exposição de alguns padrões dos atos internacionais da diplomacia brasileira para área de energia. / This dissertation analyses Brazilian foreign policy in the energy field during Lula da Silva’s presidential terms. Energy is a strategic issue to every state and has been conditioning the International System framework and the power distribution at least since the First Industrial Revolution. The search for energy security has been a constant objective for states with deficits in their energy production. The solution for this issue might be both domestic and a foreign policy result. Brazilian energy status shows a deficit, which indicates it will act in order to ensure its energy supply. While this force applies its imperatives to all state actions, there was also the South-South Cooperation as a powerful incentive to the Brazilian diplomatic operation in the foreign sphere during the analyzed period. The main objective of this text is to identify what was the Brazilian diplomatic operation’s guiding line, if there is one. The main hypothesis is that Brazilian diplomacy was mainly guided by the South-South Cooperation axis. The main empiric materials were the National Energy Balance’s historical series and the International Acts, collected in the MRE’s official online platform (Concórdia). Lastly, our research results are twofold, the identification of incentives produced by the national energy matrix to the diplomatic operation and the exposition of some patterns in the Brazilian diplomatic International Acts to the energy field.
58

Využívání obnovitelných zdrojů energie v Jihočeském kraji a možnosti jeho financování na úrovni Evropské unie, celostátní a regionální / Using Renewable Energy Resources in the Region of South Bohemia, and the Possibilities of its Financing at the EU, National and Regional Levels

ŘÍČKOVÁ, Lenka January 2007 (has links)
The priority objective of this work has been to analyse the possibilities of financing the usage of RER, and to draw up a summary of these financial possibilities. There have been other objectives: potential analysis of the South Bohemian region in the sphere of using renewable energy resources, analysis of the availability of financial subvention, and proposal of solution of current situation.
59

Localização de faltas para sistemas de distribuição ativos : metodologia analítica adaptativa baseada na estimativa da impedância aparente

Orozco-Henao, Cesar Augusto January 2016 (has links)
Este documento apresenta uma metodologia analítica adaptativa para localização de faltas baseada na estimativa da impedância para sistemas de distribuição ativos. A metodologia proposta combina a informação fornecida por dispositivos eletrônicos inteligentes alocados na subestação principal e nos terminais de cada unidade de Recurso Energético Distribuído (do inglês Distributed Energy Resources - DER), o conhecimento da topologia da rede e os seus parâmetros para estimar a localização da falta. A característica adaptativa é dada pelo uso de modelos elétricos lineares para considerar o efeito das DER conectadas à rede, quando a informação fornecida pelos Dispositivos Eletrônicos Inteligentes (do inglês Intelligent Electronic Devices - IED) não é disponível. Adicionalmente, uma estratégia baseada na técnica Ladder é desenvolvida para estimar a contribuição de corrente desde as DER até o ponto de falta. Esta estratégia permite considerar vários geradores conectados e seus diferentes modos de operação. A metodologia proposta foi validada com o sistema IEEE 34 barras. Este sistema foi modelado no Alternative Transients Program (ATP) e modificado pela inserção de várias unidades DER. A metodologia proposta foi validada em vários cenários. Estes cenários avaliam o efeito da distância até a falta, resistência da falta, incerteza na carga, nível de penetração de DER, número de geradores conectados e erros nas medidas ou na estimação dos parâmetros das DER quando seus modelos forem utilizados. Para estas considerações, o desempenho da formulação proposta é satisfatório, apresentando erros menores do que 3%. / This document presents an adaptive analytical impedance-based fault location methodology for active distribution systems. The proposal combines information provided by Intelligent Electronic Devices (IEDs) located in the substation, each Distributed Energy Resources units terminal, the knowledge of the network topology as well as its parameters to estimate the fault location. Its adaptive feature is given by the use of linear analytical equivalent models to consider of DER effect in case the information provided by a local IED is not available. Additionally, a ladder-based technique is proposed to estimate the current contribution from of DER to the fault point. This process allows considering several DER connected and their different operation modes. The proposed methodology is validated on the IEEE 34-node test feeder. This system is modeled on ATP/EMTP and modified with the insertion of several DER units. The methodology is validated by considering several scenarios. These scenarios evaluate the effect of fault distance, fault resistance, load variation, DER penetration level, numbers of DERs connected and errors in the DER parameters. For these considerations, the proposed methodology performance is satisfactory, presenting fault location errors below 3%.
60

O uso de fontes limpas de energia na indústria paulista: um estudo envolvendo a técnica do incidente crítico e a análise conjunta / The use of clean energy resources in the São Paulo state industry: a study involving the critical incident technique and conjoint analysis

Flávia de Castro Camioto 10 June 2010 (has links)
O presente trabalho tem o objetivo de identificar fatores intervenientes na adoção de energias limpas nos principais setores industriais do Estado de São Paulo. Para tanto, apresenta a fundamentação teórica sobre os diversos temas pertinentes a pesquisa, tais como: o atual cenário energético brasileiro e o desenvolvimento sustentável, bem como o estudo dos métodos aplicados. A análise dos dados realizada teve caráter qualitativo e quantitativo, por meio, respectivamente, da Técnica do Incidente Crítico e da Análise Conjunta. A aplicação da Técnica do Incidente Crítico forneceu os atributos que as empresas consideram importantes no processo de escolha. Já a Análise Conjunta, técnica estatística multivariada de análise de dados, foi utilizada para determinar a utilidade e importância relativa dos atributos relevantes na escolha das empresas. Com os resultados da pesquisa acredita-se que as empresas usuárias e não usuárias de energias limpas poderão ter conhecimentos sobre a opinião de seus pares com relação às vantagens e desvantagens do uso destes energéticos nos processos produtivos, assim como ao governo estabelecer estratégias adequadas para orientar e estimular a adoção de energias que promovem baixo impacto ao meio ambiente. / The scope of the present work is to identify intervening factors in the adoption of clean energy resources in the main industrial sectors of the São Paulo state. In order to perform such evaluation, a theoretical reasoning on the various relevant issues related to the research shall be displayed, such as: the current brazilian energy context and sustainable development, as well as the study of applied methods. The data analysis was realized guided on a qualitative and quantitative basis, by means, respectively, of the Critical Incident Technique and the Conjoint Analysis. The application of the Critical Incident Technique has imputed capabilities that companies regard as pivotal in the selection process. The Conjoint Analysis, on its hand, multivariate statistics technique on data analysis, was used in order to determine the utility and relative importance of the capabilities relevant to the companies\' selection. Based on the results inferred from the research it may be conjectured that companies that adopt and do not adopt clean energy resources may acquire acknowledge about the opinion of its couples in what it concerns the advantages and disadvantages of the use of these energetic in these productive processes, as well the government may set to establish adequate strategies in order to instruct and encourage the adoption of energy resources that promote a lesser impact to the environment.

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