Estudo comparativo de medição de força de corte no processo de retificação

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Monitoramento da dressagem do processo de retificação

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Prognóstico do consumo de energia elétrica nos sistemas urbanos de abastecimento de água em pequenos e médios municípios da região paulista do vale do rio Paraíba do Sul

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Planejamento da expansão de sistemas de transmissão considerando análise de confiabilidade e incertezas na demanda futura

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Fluxo de potência ótimo em sistemas multimercados através de um algorítmo evolutivo multiobjetivo

Pós-graduação em Engenharia Elétrica - FEIS

O setor elétrico brasileiro: passado e futuro

Este artigo analisa as possibilidades de uma estratégia nacional da política energética com visão de longo prazo, que sinalize, tanto para as agên­cias do governo quanto para a iniciativa privada, o rumo que se deseja seguir e que garanta as responsabilidades e o atendimento à sociedade. Por isso, re­toma as características da formação e do desenvolvimento inicial do setor elé­trico brasileiro, destacando a montagem de um eficiente modelo institucional estatal que garantiu, durante décadas, o crescimento econômico e o atendi­mento à população. Em seguida analisa, resumidamente, as crises que carac­terizavam o setor e as empresas, a partir dos anos 70, e seus desdobramentos que desembocaram na organização de uma reforma institucional privilegian­do a participação da iniciativa privada no setor. A parte final do artigo analisa diversos problemas, tendências e questões ainda em aberto decorrentes da marcha da transição rumo ao novo modelo institucional e da crise de energia elétrica mais recente. Destaca a importância das decisões da administração pública na transição e da revisão de conceitos relativos à reforma do Estado, no caso os limites do estado mínimo e dos mercados competitivos, na elabo­ração de uma estratégia de longo prazo para o setor.

A meta-heurística de busca dispersa aplicada no planejamento da expansão de sistemas de transmissão

Pós-graduação em Engenharia Elétrica - FEIS

Thermodynamic and economic analysis of hydrogen production integration in the Brazilian sugar and alcohol industry

One of the biggest challenges today is to develop clean fuels, which do not emit pollutant and with viable implementation. One of the options currently under study is the hydrogen production process. In this context, this work aims to study the technical and economical aspects of the incorporation process of hydrogen producing by ethanol steam reforming in the sugar cane industry and MCFC (molten carbonate fuel cell) application on it to generate electric power. Therefore, it has been proposed a modification in the traditional process of sugar cane industry, in order to incorporate hydrogen production, besides the traditional products (sugar, ethylic, hydrated and anhydric alcohol). For this purpose, a detailed theoretical study of the ethanol production process, describing the considerations to incorporate the hydrogen production will be performed. After that, there will be a thermodynamic study for analysing the innovation of this production chain, as well as a study of economic engineering to allocate the costs of products of the new process, optimising it and considering the thermoeconomics as being as an analysis tool. This proposal aims to improve Brazil's position in the ranking of international biofuels, corroborating the nation to be a power in the hydrogen era. (C) 2013 Elsevier Ltd. All rights reserved.

Wilsonismo e mudanca: analise da abordagem wilsoniana na politica externa das administracoes Bill Clinton e George W. Bush

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Uma investigação do minos e sua aplicação ao problema de fluxo de potência ótimo

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estudo da convecção natural no interior de cavidades para aplicação em isolamento transparente de coletor solar plano

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Transmission Expansion Planning Via a Constructive Heuristic Algorithm in Restructured Electricity Industry

The transmission expansion planning problem in modern power systems is a large-scale, mixed-integer, nonlinear and non-convex problem. this paper presents a new mathematical model and a constructive heuristic algorithm (CHA) for solving transmission expansion planning problem under new environment of electricity restructuring. CHA finds an acceptable solution in an iterative process, where in each step a circuit is chosen using a sensitivity index and added to the system. The proposed model consider multiple generation scenarios therefore the methodology finds high quality solution in which it allows the power system operate adequacy in an environment with multiple generators scenarios. Case studies and simulation results using test systems show possibility of using Constructive heuristic algorithm in an open access system.

A NS-2 simulation model for DNP3 protocol over IEEE 802.15.4 wireless protocol toward low cost simulation of Smart Grid applications

Faced with an imminent restructuring of the electric power system, over the past few years many countries have invested in a new paradigm known as Smart Grid. This paradigm targets optimization and automation of electric power network, using advanced information and communication technologies. Among the main communication protocols for Smart Grids we have the DNP3 protocol, which provides secure data transmission with moderate rates. The IEEE 802.15.4 is another communication protocol also widely used in Smart Grid, especially in the so-called Home Area Network (HAN). Thus, many applications of Smart Grid depends on the interaction of these two protocols. This paper proposes modeling, in the traditional network simulator NS-2, the integration of DNP3 protocol and the IEEE 802.15.4 wireless standard for low cost simulations of Smart Grid applications.

Análise de desempenho de lâmpadas LEDs e LFCs como alternativas em iluminação residencial em função da implementação da portaria ministerial n° 1007 que limita o uso de lâmpadas incandescentes no Brasil

With the imposition of the suspension of production and subsequent banning of incandescent light bulbs will be necessary to replace it by other more energy-efficient. Although the main alternative is the compact fluorescent lamp, the environmental impact caused by it due to incorrect disposal and the amount of harmonics included in the network resulting in losses related to the quality of electric power system makes them sought new alternatives for lighting systems that are efficient and have low environmental impact. In this context, the LED (Lighting Emitting Diode), based on solid-state components, is presented as an option for new projects and replacement of existing lighting. In this work we studied aspects of energy, environmental and economic impacts of a possible replacement of conventional lighting systems for new technology. From laboratory tests and surveys of the costs of different types of lamps used for residential lighting, we performed a comparative analysis considering energy and economic aspects which showed that the LED technology, but has a high initial investment, it is best when power quality and environmental preservation are relevant factors in decision making for the choice of technology to be used in the lighting system

Cinética de degradação do sistema resina epóxi/fibra de carbono

With the increasing demand for electricity, the retraining of transmission lines is necessary despite environmental restrictions and crossings in densely populated areas to build new transmission and distribution lines. Solution is reuse the existent cables, replacing the old conductor cables for new cables with higher capacity power transmission, and control of sag installed. The increasing demand for electrical power has increased the electric current on the wires and therefore, it must bear out temperatures of 150°C or more, without the risk of the increasing sag beyond the established limits. In the case of long crossings or densely populated areas, sag is due to high weight of the cable on clearance. The cable type determines the weight, sag, height and the towers dimensions, which are the items that most influence the investment of the transmission line. Hence, to reduce both cost of investment and maintenance of the line, the use of a lighter cable can reduce both number and the height of the towers, with financial return on short and long term. Therefore, in order to increase the amount of transmitted energy and reduce the number of built towers and sag, is recommended in the current work substitute the current core material (steel or aluminium) for alternatives alloys or new materials, in this case a composite, which has low density, elevated stiffness (elasticity module), thus apply the pultruded carbon fiber with epoxy resin as matrix systems and perform the study of the kinetics of degradation by thermogravimetric analysis (TGA), dynamic mechanical analysis (DMA) and differential scanning calorimetry (DSC), according to their respective standards