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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.
141

[en] THE CONTRIBUTION OF INTELLIGENT COMPUTER TECHNOLOGY IN THE MANAGEMENT OF THE PRODUCTION OF ELECTRICITY USING WIND POWER / [pt] A CONTRIBUIÇÃO DA TECNOLOGIA COMPUTACIONAL INTELIGENTE NA GESTÃO DA PRODUÇÃO DA ENERGIA ELÉTRICA UTILIZANDO POTENCIAL EÓLICO

MARCELO CORREA DE MORAES 20 June 2012 (has links)
[pt] As grandes companhias de energia eólica buscaram durante muito tempo por uma solução eficiente e economicamente viável para integração de sistemas e obtenção de maior alinhamento entre o negócio e tecnologia. SOA apareceu e vem sendo adotado por algumas destas empresas para tal finalidade. Estatísticas dizem que entre as dez maiores empresas de energia, cinco já adotam SOA como solução para seus problemas gerenciais. SOA foi elaborado pensando-se nestas corporações, mas recentemente passou-se a discutir sua aplicabilidade no mercado exclusivo de energias. Neste contexto, este trabalho se propõe analisar a aplicabilidade de SOA a Energia Eólica, propondo algumas idéias para que esta adequação possa ocorrer e realizando um estudo de caso na implantação para estas empresas, fazendo uso de tecnologias e ferramentas gratuitas. / [en] Currently, sustainable technology is an objective study everywhere in the world, since the energy industry needs intelligent alternatives to transform Green Energy into something profitable, having little environmental impact and greater efficiency in its production processes. Wind power is an alternative energy source with the largest number of studies by industry and science displaying all the proper factors to healthy living with Green Energy. With the research conducted over the past two years, the need was perceived, in real cases, for a technology associated with the Intelligent Computational Wind Energy in terms of better energy use for both the producer and for end consumers. In situ monitoring and research were carried out by wind energy companies based in Fortaleza, Brazil, having wind farms in their respective cities, such as at the Port of Pecém by Bons Ventos Engenharia and also in the state of Rio Grande do Norte. Monitoring was performed and, while headquartered in Denmark (Europe), on site research was carried out by a generator supplier for wind energy (Suzlon Brazil). These field studies took nearly three months to complete while adhering to all procedures, addressing all issues and holding several internal meetings. In all companies, components such as generators and transformers are bought from European suppliers, but the software used to manage such parts are Brazilian and often made within the company since they have no specific products with the necessary quality they need. The analyses of the visited companies are made in simple Excel spreadsheets (Microsoft Office) for workers with little skill in completing spreadsheets. The purpose of this work is to allow greater control and higher quality information to the company and the consumer. Making wind power into something extremely productive and financially viable would prove to be quite salutary for all mankind. Aiming to avoid malfunction of aero generators resulting from errors or from maintenance worker in order of achieving increased productivity, as well as enabling companies to have greater access to their factories in real time, reducing the risk of loss and a greater production control which facilitates decision making for administrators. The proposed Service Oriented Architecture (SOA) provides greater flexibility and integration between technology and business strategy. One of the principles governing this type of architecture is the integration of existing systems through an integration layer. Service-Oriented Architecture (SOA) proposes a kind of bus (ESB - Enterprise Service Bus), through which legacy applications can be aggregated and shared. The purpose is to make the most common features of a system capable of reuse regardless of the technology they were built upon, but this should be translated into a language or protocol standard, XML. The goal implicitly in the SOA model is that business applications may one day be treated with reference to services that are used. The model used for the SOA in the Wind Energy is called Software Engineering by Prototyping. After some improvements of companies with SOA, some plants were already able to generate power for small towns or neighborhoods, since, before the SOA, were sold to smaller power plants and then passed on to consumers. With the arrival of new technology it is possible to transfer immediately to homes, apartments or industries. This example was identified in Wind Station located in the Beach Park in Fortaleza (CE). Case Study in Choice of SOA Wind Energy In field trials conducted in Ceará and RN, wind farms were seen as very small, less than 15 aero generators, where the company does not know, for example, the best time to turn off its aero generators due to lack of wind, leaving only one input port of the ESB (Enterprise Service Bus), SOA equipment, thus a Java program may be installed to measure the wind velocity and once it becomes less than 2 m / s the aero generators stop automatically, maintaining the parts’ condition and decreasing expenses for these small wind farms. With companies that have wind farms in several places, the need for SOA is extreme because we have to choose the best software in order to address the needs of all wind farms. After all, one reason for using SOA is the reuse of programming code which is implemented in various plants, immense profitability and all will be controlled remotely by one simple computer. By establishing a central SOA along with a powerful ESB (Enterprise Service Bus), many doors will be opened for the central computer and for each path set a wind farm; within each one specify each aero generator and obtain real-time wind speed, creating profit by each aero generator every second of use. With this solution, the company s management team would know who would be profiting, who would be at a loss, which would be required to stop all activities, and know the wind speed of each aero generator in wind farms in each business group, control of any wind farm is made possible, avoiding loss, machine problems, substantially lower maintenance cost and improved profitability. After months of research in the field (in situ) and advanced studies for two years, the vulnerability of computer systems was identified in the wind energy industry. There are companies with investments in some cases millions of dollars which have no real-time results of their aero generators, profits, preventing errors or scheduled maintenance, putting many in financial loss. With SOA, a program written in JAVA programming language within the ESB (Enterprise Service Bus) can be used, for example, to calculate the amount of times that a lamp was lit, allowing the user to be aware of how much energy would be spent in each bulb in your home or office. Throughout this work were presented concepts of SOA and Wind Energy. The question of using SOA by these wind farms was addressed, addressing some particular questions that should be taken into consideration in order for this adoption to be made in its best form. We propose some ideas and a change in the strategy of adopting SOA, which were put into practice through two softwares and a screen ESB Integration Sterling. Surely the part that will benefit most from adopting SOA in the wind energy industry will be the management area, since the advance of information technology and engineering enhances efficiency and provides minimal losses, things in which prior to SOA technology with wind energy were normal, but Bons Ventos in Fortaleza already use these techniques based in this dissertation and is satisfied with the results achieved in its company. In real time, they can immediately stop the aero generators so that the wind do not financially compensate the maintenance of those left on, permitting facility operators to work more at ease. After all, when no wind is present and the aero generator is off by SOA equipment is exactly the best time to provide maintenance. In this current scenario, the recommendation for a company desiring to use wind energy is to wait for the development of this technology in regard to the cost-benefit ratio. The standards established for this type of captured energy are almost completely formatted, however investments are still quite expensive, namely equipment, skilled labor and control software. The use of SOA is revolutionizing information technology and this work contributed to the achievement of growth and development in the wind energy industry. Open source tools specifically made for SOA have not reached the same degree of maturity as other proprietary solutions. Future efforts can be directed towards this as well as how they can be improved by the best combination and adding new features.
142

Sistemas fotovoltaicos e eólicos: metodologia para análise da complementaridade espacial-temporal com aplicação no dimensionamento e análise de risco financeiro. / Photovoltaic and wind systems: methodology for analysis of spatial-temporal complementarity with application in the design and analysis of financial risk.

Tello Ortíz, Elvis Richard 09 May 2014 (has links)
Este trabalho propõe caracterizar a complementaridade espacial-temporal entre energia eólica e solar fotovoltaica entre regiões do Brasil e estudar, no âmbito da comercialização de energia elétrica no Setor Elétrico Brasileiro - SEB, se um portfólio formado por estas fontes trazem vantagens econômicas relevantes para o investidor. Para atender a estes objetivos, foram estudados métodos para tratamento dos dados como a correção da irradiância solar, cálculo da energia gerada pelas fontes estudadas, o ambiente de contratação de energia elétrica no Brasil, métodos de otimização e modelos de análise de risco para contratação de energia no mercado livre de energia. A metodologia proposta para responder as questões colocadas foi aplicada em um estudo de caso envolvendo três regiões brasileiras em um horizonte de dez anos. Concluiu-se que existe a complementaridade energética entre as fontes nas diferentes regiões estudadas e em diferentes períodos de tempo. Confirmou-se que tecnicamente pode-se reduzir a oscilação na geração de energia analisando as fontes de forma complementar, porém, o custo de instalação da fonte fotovoltaica ainda é muito alto, inviabilizando até o momento investimentos em larga escala e de forma complementar a fonte eólica. Também verificou-se, dentro dos locais avaliados, que somente um dos três locais apresentou benefício econômico-financeiro com a formação de portfólio das fontes eólica e solar atuando no mercado de venda de energia e atendendo os critérios de risco limite estabelecidos quando avaliadas segundo a ótica da maximização da receita no mercado livre. / This thesis proposes to characterize the spatial-temporal complementarity between wind and solar photovoltaic energy between regions of Brazil and study, in the marketing of electricity in the Brazilian Electrical Sector - SEB, a portfolio formed by these sources bring significant economic benefits to the investor. To meet these goals, methods for data processing were studied as correction of solar irradiance calculation of the energy generated by the sources studied, the environment of contracting electricity in Brazil, optimization methods and models for risk analysis for contracting energy in the free energy market. The proposed methodology to answer the questions was applied in a case study involving three Brazilian regions with a horizon of ten years time series. It was concluded that there is complementarity between energy sources in the different regions studied and in different time periods. It was confirmed that technically can reduce the fluctuation in power generation by analyzing the complement of sources, however, the installation cost of photovoltaic power is still too high, preventing yet large-scale investments and complementary way the source wind. Also it was found within the sites evaluated, only one of the three sites presented economic and financial benefit by the portfolio of wind and solar sources acting in the sale of energy market and considering the risk criteria limit established when evaluated according to perspective of maximizing revenue in the free energy market.
143

Modelagem para o aproveitamento sustentável dos biocombustíveis, energia eólica e solar dentro do PIR local: estudo de caso do PIR da Região de Araçatuba / Modeling for sustainable use of biofuels, wind and solar energy within the regional IRP : the case IRP in the administrative region of Aracatuba

Bernal, Jonathas Luiz de Oliveira 21 August 2009 (has links)
O objetivo do trabalho é avaliar os recursos energéticos eólico, solar e biocombustíveis disponíveis na Região Administrativa de Araçatuba, através da metodologia de Planejamento Integrado de Recursos Energéticos, que busca sistematizar e qualificar os impactos inerentes à utilização energética integrando a oferta e a demanda e buscando o menor custo completo considerando as características de cada recurso energético nas dimensões ambiental, social, política e técnico-econômica. Trabalhando com a Previsão de Demanda para os cenários energéticos Tendencial, Sustentável, Otimista e Sustentável-Primoroso para a integração dos Recursos energéticos ao longo do Tempo e considerando os Vigilantes do Mapeamento Energoambiental, buscando o atendimento de demanda local e de exportação de energia. Permitindo assim concluir que os recursos energéticos considerados poderão atender os requerimentos da demanda em todos os cenários, porém com a possibilidade de esgotamento em determinados cenários com horizonte de planejamento maiores que 30 anos. / The aims of this work is to evaluate the wind power, solar energy resources and biofuels available in Araçatuba through integrated resources planning methodology, which seeks to systemize and qualify the impacts associated with the use of energy by integrating supply and demand and seeking the lowest full-cost recital characteristics of each energy resource in environmental, social, political and technical-economic dimensions. Working with the demand forecast for trend, sustainable energy scenarios, optimistic and sustainable-prime as a PIN for the integration of energy resources over time, and considering the vigilant of Energy-environmental parameters, fetching mapping meeting local demand and export of energy. Thus conclude that the energy resources considered may meet the requirements of demand in all scenarios, but with the possibility of exhaustion in certain scenarios with planning horizon larger than 30 years.
144

Proposta de metodologia para elaboração de projetos de centrais de geração de energia eólica. / Proposed methodology for projects of wind power plants generation.

Seki, Leandro Yudi 07 November 2014 (has links)
As condições do setor eólico internacional em crise e a subsequente instalação de fornecedores no Brasil tem auxiliado no aumento de instalações de Centrais de Geração Eólica (CGE) no Brasil. A quantidade de projetos de detalhamento e implantação de centros geradores de energia eólica cresceram na mesma proporção. Os projetos dos parques eólicos no Brasil são concebidos, projetados, detalhados e implantados por um conjunto de profissionais de diferentes disciplinas e especialidades que, a partir de informações de referência e delimitações do escopo de trabalho, realizam suas atribuições em momentos distintos dentro do ciclo de implantação de um CGE. Durante a concepção, são considerados parâmetros, tais como interferências físicas, especificação de equipamento, estudos básicos, análise da distribuição, transmissão de energia e capacidades de geração de energia elétrica. Durante toda a fase de desenvolvimento do projeto, um dos principais pontos de atenção são as análises de risco do projeto que avalia o andamento do projeto e visa reduzir os riscos de fracasso da empreitada. Caso estes índices sinalizem problemas ou barreiras intransponíveis, as atividades de detalhamento do projeto eólico devem ser interrompidas. Este trabalho tem como objetivo desenvolver uma metodologia que auxilie na análise de riscos de projetos de detalhamento eólico. Esta metodologia auxiliará profissionais menos experientes ou que não atuem no mercado eólico e precisam de subsídios técnicos para elaborar relatórios aos responsáveis pelo planejamento estratégico de futuros empreendimentos eólico. / The crisis of the international wind industry and the subsequent installation of suppliers in Brazil has helped in the increase of the central premises of wind generation (CGE) in Brazil. The amount of detailing projects and deployment of wind energy generating centers grew in proportion. The wind farms projects in Brazil are designed, engineered, detailed and implemented by a group of professionals from different disciplines and specialties, that perform their duties at different times within the cycle development of a CGE using different reference informations and delimitations of scope of work. During design, are considered parameters such as physical interference, equipment specification, basic studies, analysis of the distribution, power transmission and generation capacity of electricity. Throughout the development phase of a project, one of the main points of attention is the project risk analysis that evaluates the progress of the project and aims to reduce the risk of failure of the venture. If these indices to signal problems or insurmountable barriers, detailing the activities of the wind project should be stopped. This work aims to develop a methodology that assists in the analysis of wind power detailed project risks. This methodology will assist less experienced professionals or professionals that are not used to work in the wind energy power market and need more information for reporting technical issues to those responsible for strategic planning of future wind projects.
145

[en] DETERMINATION OF TRANSPORT COEFFICIENTS OF A PINNED ANNULAR HEAT EXCHANGER / [pt] DETERMINAÇÃO DOS COEFICIENTES DE TRANSPORTE EM UM TROCADOR DE CALOR BI-TUBULAR PINADO

ANGELA OURIVIO NIECKELE 27 August 2012 (has links)
[pt] Os coeficientes de troca e perda de carga de trocadores de calor do tipo bi-tubular pinado foram experimentalmente determinados. Medidas do coeficiente global de troca de calor do permitiriam avaliar o coeficiente de troca do lado do ar como função do número de Reyonolds do escoamento. Os resultados foram comparados com aqueles para trocadores de calor de duto anular, sem pinos, e a comparação revelou uma grande vantagem em relação à troca de calor para os trocadores pinados. Por outro lado, a comparação mostrou sua queda de pressão é consideravelmente mais alta. Não obstante, para a mesma taxa de transferência de calor, o trocador de calor pinado seria muito mais compacto. / [en] Experiments have been performed to determine the heat transfer characteristics and pressure drop of a pinned double-pipe heat exchangers. Measurements of the overall heat transfer coefficient as function of the air-side transfer coefficients as function of the flow Reynolds number. The results were compared with those for annular duct heat exchangers, without pins, and the comparison revealed a great advantage respect to the heat transfer for the pinned exchanger. On the other hand, the comparison showed that its pressure drop is considerably higher. Nevertheless, for the same heat transfer rate, the pinned exchanger would be much more compact.
146

Avaliação energética do aumento da participação eólica no Sistema Interligado Nacional, com ênfase na concentração de plantas geradoras na região Nordeste e rebatimento nas condições de atendimento da demanda de pico. / Energy assessment of the increase of wind participation in the National Interconnected System, with emphasis on concentration of the generating plants in the Northeast and under the conditions of attendance of the peak demand.

Kawana, Selma Akemi 10 December 2013 (has links)
A recém-adquirida competitividade pela energia eólica frente a outras fontes alternativas e, até mesmo, convencionais tem sido comemorada pelo setor de energia elétrica. No entanto, a base para essa comparação leva em conta apenas os parâmetros dos investimentos do parque viabilizado, não sendo considerados outros fatores inerentes à inserção da fonte na matriz, como, por exemplo, o aumento do risco ao sistema, investimento necessário à ampliação da Rede Básica para escoamento da energia para o centro de carga e os custos com redespacho de geração, reserva girante e controles do sistema. O maior potencial está concentrado no Nordeste e o maior centro de carga no Sudeste, assim, em caso de exploração intensiva do potencial da fonte, será necessário passar por grandes investimentos em reforços e ampliações da rede básica. A partir desse panorama, busca-se realizar as primeiras análises de sensibilidade sobre a eficiência econômica dos parques eólicos instalados no Nordeste e, ao mesmo tempo, analisar as condições de atendimento da ponta. / The newfound competitiveness in wind power compared to other alternative and even conventional energy sources has been celebrated by the electric power sector. However, the basis for this comparison takes into account only the parameters of the Capex, not considering other factors inherent in the insertion of the source in the array, for example, increase the risk to the system, expansion of the investment necessary for Basic network for transport of energy to the load center and the cost of redispatch generation, spinning reserve, and system controls. The greatest potential is concentrated in the Northeast and the largest load hub in the Southeast, so, in case of intensive exploitation of the potential of the source, large investments in reinforcements and expansions of the grid will be necessary. From this overview, we attempt the firsts sensitivity analysis on the economic efficiency of wind farms in the Northeast and the load peak supply conditions.
147

Análise transitória de faltas em geradores de indução duplamente alimentados no contexto da energia eólica. / Transient fault analysis of doubly fed induction generator in the context of wind energy.

Bruno Harllen Pontes da Silva 30 January 2018 (has links)
Este trabalho investiga o comportamento transitório da topologia de turbina eólica baseada em Doubly Fed Induction Generator (DFIG) ao simular faltas nos terminais do estator e rotor da máquina. Um modelo DFIG foi simulado no software Matlab/Simulink utilizando uma fonte de tensão com equivalente de Thévenin para simular a rede elétrica, um transformador de interface, uma máquina de indução de 2,0MVA e conversores fonte de tensão de dois níveis VSC conectados na topologia back-to-back. O controle dos conversores foi concebido a partir da estratégia de controle vetorial utilizando controladores PI projetados a partir do Método Ótimo Simétrico. A proteção crowbar e proteção de corrente dos conversores também foram implementados na simulação e depois validados para simular o comportamento aproximado do sistema DFIG real e, assim, verificar o comportamento transitório do DFIG no momento de faltas monofásicas, bifásicas e trifásicas nos terminais da máquina. Essa pesquisa possibilitou analisar o transitório eletromagnético a partir de gráficos de grandezas coletadas em vários pontos do sistema no momento dos disturbios, permitindo mostrar a influência do conversor back-to-back no comportamento do sistema, além de proporcionar uma base teórica do modelamento dinâmico, detalhar o projeto de controle do conversor back-to-back e projetar duas das principais proteções do sistema DFIG. Para isso, foi simulado seis casos de falta nos terminais da máquina, coletado gráficos e feito análises detalhadas do comportamento de nove grandezas distintas. Este trabalho proporciona uma base teórica do modelamento dinâmico, detalhamento do projeto de controle do conversor back-to-back, projeto de duas das principais proteções do sistema DFIG e análise do comportamento dinâmico do sistema máquina-conversores no momento de distúrbios. / This work investigates the behavior of the topology of the wind turbine based on Doubly Fed Induction Generator (DFIG) when simulating faults in the stator and rotor machine terminations. A DFIG model was simulated in the Matlab / Simulink software using a Thevenin voltage source equivalent to simulate an electrical network, an interface transformer, a 2,0MVA induction machine and two-level VSC voltage source converters connected in the back-to-back topology. The converter\'s control was conceived from the vector control strategy using PI controllers tuned with Symmetric Optimum Method. The crowbar protection and current protection of the inverters were also implemented in the simulation and then validated to simulate the approximate behavior of the real DFIG system and then to verify the transient behavior of the DFIG at the moment of singlephase, two-phase and three-phase faults at the machine terminals. This research makes it possible to analyze the electromagnetic transient from graphs of quantities collected at various points of the system at the time of the disturbances, allowing to show the influence of the back-to-back converter on the behavior of the system, in addition to a theoretical basis of dynamic modeling, detailing the control design of the back-to-back converter and designing two of the main DFIG system protections. For this, six fault cases were simulated at the machine terminals, collected graphs and performed detailed analyzes of the behavior of nine different quantities. This work provides a theoretical basis for dynamic modeling, detailing the control design of the back-to-back converter, designing two of the main protections of the DFIG system and analyzing the dynamic behavior of the machine-converter system at the time of disturbances. The objective of this investigation is to discover information still scarce in the literature about the transient behavior of the DFIG topology, including the generating unit, CC link and converters at the moment of internal faults to the system.
148

Micro e minigeração eólica e solar no Brasil: propostas para desenvolvimento do setor. / Micro and mini power generation by wind and solar resources in Brazil: Proposals for development of the sector.

Daniel Tavares Cruz 13 March 2015 (has links)
O setor de micro e minigeração de energia elétrica encontra-se num estágio inicial de desenvolvimento no Brasil que pode ser considerado aquém de suas potencialidades em contraste com os recursos energéticos renováveis do país, passados três anos do estabelecimento dos primeiros incentivos de órgãos públicos e privados e da promulgação de regulações específicas voltadas para o setor, indicando uma possível conjuntura atual insuficiente para um crescimento mais consistente e dinâmico. Com tal problemática em vista, a presente dissertação tem como objetivo contribuir no desenvolvimento do setor nacional de micro e minigeração eólica e solar, tecnologias com maior potencial de instalação, apresentando propostas de ações que podem solucionar questões econômicas, técnicas e regulatórias que possivelmente estão dificultando o alcance de um maior equilíbrio de interesses entre os principais agentes envolvidos nesta atividade econômica, ou seja, potenciais usuários, concessionárias de energia, fabricantes e órgãos do governo, aumentando a atratividade e dinamizando os negócios no setor, com benefícios diretamente estendidos ao desenvolvimento do país como um todo. A construção das propostas teve como base o estudo da atual conjuntura e a identificação de possíveis barreiras existentes ao desenvolvimento da micro e minigeração de energia elétrica no Brasil através de análise crítica e mensurável da atual maturidade do setor, isto é, do atual estágio de desenvolvimento e da margem de evolução possível nos aspectos mais relevantes para esta atividade, ou seja, regulações, incentivos, capacidade tecnológica e capacitação profissional. Além disso, observou-se que grande parte dos brasileiros desconhece o tema, porém, depois que cientes do assunto, o percebem como relevante e demonstram disposição significativa para adotar tais sistemas de geração renovável em suas unidades consumidoras. Por fim, avaliou-se que caso ao menos parte das ações descritas nas propostas forem efetivamente implantadas, a perspectiva é que haja uma evolução no ambiente técnico e econômico do setor no país, tornando-o favorável ao desenvolvimento da atividade de micro e minigeração de energia. Espera-se que as propostas apresentadas nesta dissertação possam ser utilizadas como base para trabalhos futuros de instituições governamentais e privadas, fabricantes, centros de pesquisas, universidades e demais interessados no assunto para serem validadas, aperfeiçoadas e detalhadas para um possível estabelecimento no país. Assim, o trabalho apresenta que se houver desenvolvimento de ambiente favorável, o Brasil desponta como país com alto potencial no mercado de micro e minigeração de energia elétrica e que há possibilidades de ações governamentais e privadas, passíveis de discussões e estudos, para fomentar este ambiente. / The micro and mini electricity power generation sector is at an early stage of development in Brazil that can be considered below of its potential in contrast to the country renewable energy resources, three years after the establishment of the first public and private incentives and the enacting of specific regulations for the sector, indicating a possible insufficient conjuncture for a more consistent and dynamic growth. Considering this problematic, the purpose of this work is to contribute to the development of national micro and minigeneration industry by wind and solar photovoltaic resources, technologies with greatest potential for being installed currently, presenting action proposals that can solve economic, technical and regulatory issues that possibly are hampering the achievement of a better interests balance between the major players involved in this economic activity, i.e., potential users, distribution companies, manufacturers and government agencies, increasing attractiveness and boosting business in this sector, with benefits directly extended to the environment and to the development of the country as a whole. The construction of the proposals was based on the study of the current situation and identifying possible existing barriers to Brazil micro and minigeneration development through a critical and measurable analysis of the current sector maturity, in other words, the current stage of development and the margin of possible evolution on the most relevant aspects of this activity, i.e., regulations, incentives, technological capacity and workers professional training. Furthermore, it was observed that most Brazilians are not familiarized with this subject, but after aware, they perceive it as relevant and demonstrate significant willingness to adopt such renewable generation systems in their consumer units. Finally, it was evaluated that if at least some of the actions described in the proposals are effectively implemented, the perspective is for a technical and economic environment progress, making it favorable for a micro and minigeneration energy activity development. It is expected that the proposals presented in this thesis can be used as a basis for future works of government and private institutions, manufacturers, research centers, universities and others interested in the subject to validate, improve and detail them for a possible establishment in the country. As a result, the thesis presents that if a favorable environment is developed, Brazil can stand out as a country with high potential in the micro and minigeneration electricity market and that there are possibilities of government and private actions, likely to discussions and studies, to foster this environment.
149

Scale Model Experiments on Floating Offshore Wind Turbines

Naqvi, Syed Kazim 23 May 2012 (has links)
This research focuses on studying the feasibility of placing large wind turbines on deep-ocean platforms. Water tank studies have been conducted using the facilities at Alden Research Laboratories (ARL) on 100:1 scale Tension Leg Platform (TLP) and Spar Buoy (SB) models. Froude scaling was used for modeling the offshore wind turbine designs. Primary components of the platform turbine, tower, and cable attachments were fabricated in ABS plastic using rapid prototyping. A wireless data acquisition system was installed to prevent umbilical data cables from affecting the behavior of the platform when exposed to wave loading. In Phase I testing, Froude-scaled TLP and Spar Buoy models at a 100:1 scale were placed in a water flume and exposed to periodic waves at amplitudes ranging from 0.5 cm - 7.5 cm and frequencies ranging from 0.25 Hz - 1.5 Hz. The testing was conducted on simple tower and turbine models that only accounted for turbine weight at the nacelle. In Phase II testing, emphasis was placed on further testing of the tension leg platform as a more viable design for floating offshore wind turbines. The tension leg platform scale model was improved by adding a disc to simulate drag force incident at the top of the tower, as well as a rotor and blades to simulate the gyroscopic force due to turbine blade rotation at the top of the tower. Periodic wave motions of known amplitude and frequency were imposed on the model to study pitch, heave, roll, surge, sway motions and mooring cable tensions (in Phase II only) using accelerometers, inclinometers, capacitance wave gage, and load cells. Signal analysis and filtering techniques were used to refine the obtained data, and a Fourier analysis was conducted to study the dominant frequencies. Finally, Response Amplitude Operators (RAO's) were plotted for each data set to standardize the results and study the overall trend with respect to changes in wave amplitude and frequency. For Phase I testing, it is shown that surge motion of the platform dominates other motions for both the tension leg platform and spar buoy, and varying tether pretension has little effect on response amplitude operator values. For phase II testing, it was found that the introduction of thrust and gyroscopic forces increases sway and pitch motions as well as upstream tether forces. Coupling effects of pitch motion with roll and sway due to the presence of gyroscopic forces were also seen. The present experimental results can be used to validate the hydrodynamic kernels of linear frequency-domain models, time-domain dynamics models, and computational simulations on floating wind turbines. Numerical analysis and simulations have been conducted in a separate study at WPI. These simulations are comparable to the experimental results.
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Análise integrada dos aspectos e impactos ambientais da atividade operacional em parque eólico no sudoeste da Bahia Brasil /

Nogueira, Lucidalva Rodrigues de Souza January 2019 (has links)
Orientador: Admilson Írio Ribeiro / Resumo: A demanda por energia elétrica e seus sistemas de produção e distribuição são relevantes para a sociedade, pois está associada ao desenvolvimento das nações. Atualmente muitas empresas do ramo estão surgindo em nosso país, particularmente na região Nordeste, devido às condições ambientais para geração de energia eólica. Assim, como toda ação antrópica, a utilização dos ventos para geração de energia elétrica apresenta impactos positivos e negativos. Nesse sentido, a proposta dessa pesquisa foi realizar uma análise integrada dos aspectos e impactos ambientais na operação do Parque Eólico Complexo Alto Sertão no distrito de Morrinhos - Guanambi\Bahia. A proposta de estudo foi delineada por meio de dois métodos de avaliação de impacto ambiental: rede de interação e matriz de ponderação. Dentre os impactos positivos destacados pode ser citada a melhoria das condições de vida dos proprietários de terra os quais são contratados por arrendamento do uso da área. Outro impacto positivo significativo foi à geração de empregos na instalação e operação do empreendimento, pois sugiram oportunidades de serviços local e regional. Destaca se também como impacto positivo significativo o aumento de recursos econômicos para os municípios da região dado o aumento na arrecadação de impostos e tributos. Assim, a sociedade local entende que produção de energia eólica auxilia desenvolvimento socioeconômico. A produção de energia eólica, mesmo sendo uma fonte renovável, como toda atividade humana pro... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre

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