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Este trabalho analisa as perspectivas regulatórias e os desaos institucionais para a aplicação de elementos e princípios do Planejamento Integrado de Recursos no Brasil. Partindo da experiência norte-americana e da revisão da evolução e da reestruturação em curso no Sistema Elétrico Brasileiro, são discutidas condições e proposições direcionadas à manutenção do equilíbrio entre funções centralizadas e descentralizadas e entre competição e cooperação. Considerando as tendências do novo modelo estrutural e empresarial do setor elétrico, conclui-se que o atendimento de todas as necessidades de serviços energéticos da sociedade, através do desenvolvimento sustentável, exige, além dos mecanismos de mercado, políticas públicas e dispositivos legais e regulatórios apropriados. As alternativas de regulamentação e as proposições discutidas abrangem estrutura dos órgãos reguladores, uso racional da energia, tratamento das questões sociais e ambientais, formas de representação e participação dos cidadãos e de todos os atores envolvidos, estrutura tarifária, apropriação de rendas, qualidade do fornecimento e fontes descentralizadas. Reconhecendo que a implementação dessas propostas dependem de decisões políticas, este trabalho sugere que essas questões sejam incorporadas, de forma sistemática e coerente, ao planejamento e à regulação do Sistema Elétrico Brasileiro. / This paper analyzes the regulatory perspectives and the institutional challenges for the application of elements and principles of the Integrated Planning of Resources in Brazil. The USA IRP experience is reviewed as a reference for the study. From experience of the Brazilian Electric System evolution and restructuring, currently underway, the conditions for the maintenance of an equilibrium between centralized and decentralized functions and between competition and cooperation are discussed. The tendencies of the new structural and managerial model proposed for the electric sector indicate that the satisfaction of societal energy service needs, through sustainable development, requires more than market mechanisms. Approriate public policies and regulatory instruments may be additionally necessary to achieve this goal. The alternatives and propositions involve regulatory structure, rational use of energy, treatment of the social and environment issues, forms of citizens participation and representation, tariff structure, rent appropriation, supply quality and decentralized sources. Recognizing that the introduction of these proposals depends on political decisions, this work suggests the incorporation of these issues, in a systematic and coherent way, in the planning and regulation framework of the Brazilian Electric System.

No passado, os interessados em implantar Pequenas Centrais Hidrelétricas eram proprietários rurais, cooperativas, indústrias, concessionárias estaduais e prefeituras municipais. As Pequenas Centrais Hidrelétricas destinavam-se a serviço público ou a uso exclusivo e sua implementação dependia de concessão federal. Hoje a exploração de energia elétrica através de Pequenas Centrais Hidrelétricas pode ser encarada também como uma alternativa de negócio para investidores privados. Estes investidores, por originalmente não pertenceram ao Setor Elétrico, muitas vezes não tem o necessário conhecimento técnico para avaliar de maneira econômica e financeira o projeto da usina de seu interesse, bem como os mecanismos para a comercialização da energia produzida. Necessitam portanto de instrumentos capazes de auxiliá-los na tomada de decisão em investir numa pequena Central Hidrelétrica. O trabalho apresenta uma proposta metodológica consistente para avaliação dos benefícios energéticos e financeiros auferidos com a inserção de uma Pequena Central Hidrelétrica no Mercado Atacadista de Energia. A metodologia é aplicada na Pequena Central Hidrelétrica Carrapatos localizada numa região do estado de São Paulo denominada Alto Pardo/ Mogi na bacia hidrográfica do rio Pardo. / In the past, people interested in set up Small Hydroelectric Plants were land owners, co-operatives, industries, state concessionaires and municipalities. The Small Hydro Plants were designated to public service or exclude use and their installation depended on federal concession. Today the exploitation of electric energy through Small Hydro Plants can be faced also as an alternative business for private investors. These investor, for originally do not belong to the Electrical Sector, many times do not have the technical background needed to evaluate in an economical and financial way the project of their interest, as well as the mechanisms capable of helping them to make a decision on investing in a Small Hydro Plant. The work presents a proposed consistent methodology for evaluations of the energetic and financial benefits obtained with the insertion of a Small Hydro Plant in the Wholesale Electricity Market. The methodology is applied in the Carrapatos Small Hydro Plant placed in a region of the State of São Paulo called Alto Pardo/ Mogi in the Pardo basin.

Orientador: Maria Cristina Dias Tavares / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação / Made available in DSpace on 2018-08-16T22:19:27Z (GMT). No. of bitstreams: 1 Vidigal_RodrigoFernandes_M.pdf: 3000237 bytes, checksum: 232f1475b91d13386621a654c4a17690 (MD5) Previous issue date: 2010 / Resumo: Este trabalho apresenta uma análise do comportamento de uma linha de transmissão isolada de um pouco mais de meio comprimento de onda (2600 km) na freqüência fundamental, 60 Hz, alimentada a partir de uma barra infinita para diferentes condições de operação. Os perfis de tensão e de corrente, para diferentes condições de carregamento, são monitorados ao longo da linha. Uma análise do fator de potência da potência injetada no terminal emissor também é realizada e sua influência nos perfis de tensão e de corrente é verificada. As perdas ao longo da linha para diferentes níveis de potência transmitida são medidas e uma alternativa para minimização dessas perdas é apresentada. Uma metodologia de análise sistemática na freqüência fundamental de um sistema elétrico de potência identificando as condições críticas é também apresentada. A presente metodologia é aplicada em um sistema formado por linhas de transmissão de 500 kV existentes no sistema elétrico brasileiro, as quais são interligadas formando um tronco de 2600 km com a finalidade de representar uma linha de transmissão de um pouco mais de meio comprimento de onda. As análises feitas nesse trabalho consistem na verificação do comportamento do sistema na presença de diferentes tipos de curtos-circuitos em diferentes pontos da linha. Após a análise sistemática em regime permanente, as condições extremas podem ser simuladas em um programa de transitórios eletromagnéticos. Deste modo o comportamento da linha isolada alimentada a partir de uma barra infinita na presença de diferentes tipos de curtos-circuitos é discutido e os principais resultados são apresentados nesse trabalho. O tronco de 2600 km formado por linhas de 500 kV existentes no Brasil foi utilizado para simular a manobra de energização. As simulações incluíram diferentes técnicas de energização como o fechamento direto das fases, a utilização de um resistor de pré-inserção e o chaveamento controlado. Para cada alternativa de chaveamento foram analisadas as sobretensões transitórias e o perfil de tensão ao longo da linha. As simulações foram feitas utilizando-se os softwares ATP e PSCAD/EMTDC / Abstract: This work presents an analysis of the behavior of an isolated transmission line with a little more than half-wave length (2600 km) on fundamental frequency, 60 Hz, connected to an infinite busbar for different operating conditions. The voltage and current profiles for different loading conditions are monitored along the line. An analysis of the influence of the power factor of the transmitted energy on the voltage and current profiles along the line is performed. The losses along the line for different levels of transmitted power are measured and a method to minimize these losses is presented. A systematic review methodology in the fundamental frequency of a power system identifying the critical conditions is also presented. This methodology is applied to a system formed by 500 kV existing transmission lines in the Brazilian electrical system, which are interconnected forming an AC-link of 2600 km in order to represent a transmission line of a little more than half-wave length. The analysis made in this paper means to verify the system behavior in the presence of different types of short circuits at different points along the line. After systematic analysis in steady state, the extreme conditions can be simulated in an electromagnetic transient program. Thus the behavior of the isolated line connected to an infinite busbar in the presence of different types of short circuits is discussed and the main results are presented in this paper. The 2600 km AC-link formed by actual Brazilian 500 kV lines was used to simulate the trunk energization. The simulations included different techniques such as direct closure energization, the use of a pre-insertion resistor and the controlled switching. For each alternative it was analyzed the transient overvoltage profile along the line. The simulations were done with the software ATP and PSCAD / EMTDC / Mestrado / Energia Eletrica / Mestre em Engenharia Elétrica

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Here a temperature stable optical fiber current sensor based on the Sagnac loop interferometer and a cavity formed from two Faraday rotation mirrors is developed and tested. To the best of the author's knowledge a cavity composed of two Faraday rotation mirrors has never been used for the measurement of alternating currents. For the first time, it is shown that the maximum Faraday rotation angle for a long, static optical fiber is input polarization insensitive. Also, linear birefringence is shown to quench this angle in long optical fiber. The polarization dynamics in an optical ground wire network, for a summer period and a fall period, are reported for the first time. The highest-speed polarization changes are attributed to the high-voltage power line, i.e., the electrical current. A novel spectral analysis polarization optical time domain reflectometry method, that uses an induced birefringent event, is shown to work in long optical fiber.

South African electricity tariffs were relatively low compared to the rest of the world. The average South African business has for long taken this advantage for granted and is now surprised to realise that electricity is becoming an expensive and scarce commodity. The South African electricity supply industry is far more complex than the average person may think. The infrastructure supporting this industry is extremely costly; takes long to develop and build and requires careful planning and management. There are many sources of energy and many technologies for generating electricity. However, many of these do not appear quite ready to serve the needs of the industry. The manufacturing industry depends heavily on electricity. The recent power outages and tariff increases have served as a cruel reminder of this fact. The automotive sector has lost many days of production and the increasing electricity costs erode the profitability of the affected companies. The automotive suppliers and vehicle manufacturers have expressed their concerns. Indications are that some have reduced the number of employees and may even face bankruptcy. This research aims to gain the perspective of senior managers in the automotive industry regarding the impact of the increased electricity tariffs on their manufacturing costs. Naturally, all electricity consumers will be affected by this. However, this research aims to investigate the significance of the effect on the automotive industry as well as obtain some indication of which factors determine the level of dependency. Each company has to react strategically to the situation and apply those measures which are available to them. This research determines how strongly the industry feels about reacting and which strategic measures they will apply. The outcome is descriptive of the circumstances in the industry and indisputably serves as an indication of the financial impact of electricity tariff increases.

Abstract not available.

Weakly electric fish use a unique sensory modality in order to help them communicate, navigate and find prey. These fish emit electric discharges that are monitored by electroreceptors located in the fish's skin. Surrounding objects perturb these baseline transdermal potentials and create electric images. The study of these images has led to a better understanding of general sensory processing principles; however, many aspects of these fish's natural electrosensory environment remain unknown. To this end, a two-dimensional finite element model of Apteronotus leptorhynchus was created. Using this model, we suggest new ways by which electric fish are able to locate objects and propose that it is possible for these fish to extract useful information from their environment using their natural scanning behaviour. Our results also reveal important limitations in standard experimental paradigms that aim to mimic the effects of conspecifics. Alternative paradigms that will enable more realistic stimulation are suggested.

The BJL limit is derived and used to calculate the anomalous vector current commutator in QED. It is then shown, by a calculation with the BJL limit for double commutators, that the Jacobi identity fails for two vector currents and one axial vector current in QED. / Science, Faculty of / Physics and Astronomy, Department of / Graduate