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‣ Planejamento da operação energetica e da manutenção no sistema hidrotermico de potencia brasileiro; Hydrothermal power planning operation and maintenance planning in Brazilian power system

Andre Flavio Soares Pereira
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 15/02/2006 Português
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Nesta dissertação se avalia o estado da arte do planejamento da operação energética e da manutenção de usinas em sistemas hidrotérmicos de potência e se propõe algumas inovações. Neste contexto, se faz uma revisão crítica das metodologias de planejamento empregadas no setor elétrico brasileiro, incluindo as bases de dados que dão suporte a estas metodologias e dando destaque às práticas atuais do Operador Nacional do Sistema Elétrico (ONS); várias propostas de avanços metodológicos são feitas ao longo desta parte do trabalho. Uma outra parte desta dissertação envolve a aplicação de um modelo de otimização, a médio prazo, da operação de algumas usinas do Sistema Interligado Nacional (SIN), pertencentes a uma concessionária geradora no Estado de São Paulo, satisfazendo as metas de geração impostas pelo planejamento centralizado do SIN, realizado pelo ONS, e restrições associadas ao uso múltiplo da água nos reservatórios destas usinas, dentre outras. Várias funções-objetivo podem ser utilizadas neste modelo, dependendo das finalidades a serem atingidas nas simulações. O modelo foi aplicado ao parque gerador hidrelétrico da empresa AES, nos rios Tietê e Pardo; algumas simulações foram feitas...

‣ Planejamento da operação energetica do sistema interligado nacional baseado em modelo de controle preditivo; Long term hydrothermal scheduling of the brazilian integrated system based on model predictive control

Monica de Souza Zambelli
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 09/12/2009 Português
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O planejamento da operação energética do Sistema Interligado Nacional (SIN) é uma tarefa complexa realizada por meio de uma cadeia de modelos de médio, curto e curtíssimo prazo acoplados entre si, cada um com considerações pertinentes à etapa que aborda. A proposta deste trabalho é apresentar uma alternativa para o planejamento da operação energética de médio prazo. Foi desenvolvida uma metodologia baseada em modelo de controle preditivo, abordando os aspectos estocásticos do problema de forma implícita pela utilização de valores esperados das vazões, e fazendo uso de um modelo determinístico de otimização a usinas individualizadas, que possibilita uma representação mais precisa do sistema hidrotérmico. A análise de desempenho é feita através de simulações da operação, considerando os parques hidrelétrico e termelétrico que compõem o SIN, com restrições operativas reais, em configuração dinâmica, com plano de expansão e a possibilidade de intercâmbio e importação de mercados vizinhos. Os resultados são comparados aos fornecidos pela metodologia em vigor no setor elétrico brasileiro, notadamente o modelo NEWAVE, que determina as decisões de geração por subsistema, e o modelo Suishi-O...

‣ Contribuição para a otimização de turbinas em usinas hidrelétricas : especificação e operação; Optimized use of hydro turbines in electric power plants

Glauber Renato Colnago
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 03/02/2011 Português
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Segundo cenários de previsões, a demanda de energia elétrica no Brasil tende a continuar crescendo, implicando na necessidade de se aumentar a oferta de energia através da instalação de novas usinas. Além disto, mostra-se importante a repotenciação de usinas existentes, pois se trata de uma alternativa de custos reduzidos para expandir a oferta de energia e a adequada operação das usinas. Baseado nisto, propõe-se duas metodologias para a otimização do potencial hidrelétrico. A primeira é a especificação de turbinas hidráulicas para usinas em construção, ou em repotenciação. A segunda metodologia diz respeito à operação de usinas em uma base diária, podendo tratar unidades geradoras (turbina-gerador) com diferentes curvas de eficiência, coordenando a maximização da eficiência na geração da energia com a minimização do número de partidas e paradas dessas unidades. Para esta última metodologia, como os objetivos são conflitantes, pode-se obter diversas soluções de despacho com características de manobras de unidades e eficiência diferentes, que podem ser quantificadas para se chegar à solução mais adequada de acordo com o preço da energia e estimativas de custos de manobras. Com relação à primeira metodologia...

‣ Industrial electric load modeling.

Manichaikul, Yongyut
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: [6], 5-[356] leaves; 18200979 bytes; 18200738 bytes; application/pdf; application/pdf
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Thesis. 1978. Ph.D.--Massachusetts Institute of Technology. Dept. of Electrical Engineering and Computer Science.; MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING.; Includes bibliographical references.

‣ Quantification of aquatic environmental impact of electric power generation

Gruhl, Jim
Fonte: MIT Energy Lab Publicador: MIT Energy Lab
Tipo: Relatório Formato: 10290559 bytes; application/pdf
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This project proposes a method for creating, to the extent of their predictability, the proper and timely forecasts of the aquatic ecosystem consequences of electric power system operation. A procedure is developed and intended for use in quantifying the ecological sacrifices associated with a number of desirable regional dispatch schedules. With the use of this technique, associated with a given reliability level, optimum scheduling schemes can be used to evaluate optimum dollar cost - environmental impact pairings. A prerequisite of the model was that it be flexible enough for use in the evaluation of aquasystem impacts from either existing or hypothesized systems, that is, that it could be used either as an operational tool or as a simulation tool. Specifically demonstrated is the feasibility of the quantification of various ecological impacts and its usefulness in effecting compatibility between the power generating facilities and the aquatic ecosystem into which they have been incorporated. The method of quantification involves a probabilistic systems approach which includes a due regard for the vagaries of nature. Essentially calculated is the change in desirability to man of the ecosystem as influenced by the losses of organisms...

‣ Thermal pollution abatement evaluation model for power plant siting

Shiers, Paul Francis; Marks, David H.
Fonte: MIT Energy Lab Publicador: MIT Energy Lab
Tipo: Relatório Formato: 17483553 bytes; application/pdf
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A thermal pollution abatement model for power plant siting is formulated to evaluate the economic costs, resource requirements, and physical characteristics of a particular thermal pollution abatement technology at a given site type for a plant alternative. The model also provides a screening capability to determine which sites are feasible alternatives for development by the calculation of the resource requirements and a check of the applicable thermal standards, and determining whether the plant alternative could be built on the available site in compliance with the thermal standards. The thermal pollution evaluation model analyzes the abatement technologies of surface discharge, diffuser, cooling pond, spray canal, and wet mechanical draft cooling towers. The typical site types evaluated are a river, small lake, great lake, coastal, estuary, offshore ocean, and water poor site. The model will be used in conjunction with a Plant Evaluation Model, which analyzes the effects of fuel costs and air pollution abatement, a Plant Expansion Model, and a Generation Expansion Model to determine the optimal operating and generating plan for an electric utility. The model may also be used in conjunction with the Plant Evaluation Model to evaluate the trade offs between the dollar cost of electric power generation...

‣ Modeling of electric power demand growth

Woodard, James B.; Baughman, Martin L.; Schweppe, Fred C.
Fonte: MIT Energy Lab Publicador: MIT Energy Lab
Tipo: Relatório Formato: 1495914 bytes; application/pdf
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Paper given at MIT conference entitled Energy: Demand, Conservation and Institutional Problems, February 12-15, 1973

‣ Independent assessment of energy policy models : two case studies

Massachusetts Institute of Technology. Model Assessment Group.
Fonte: MIT Energy Laboratory Publicador: MIT Energy Laboratory
Tipo: Relatório Formato: 13822037 bytes; application/pdf
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Energy policy models are playing an increasingly important and visible role in supporting both private and public energy policy research and decision making. As importance has increased so too has the need for model review and assessment to assist in establishing model credibility for users and those affected by model-based policy research. Toward this end EPRI has sponsored the M.I.T. Energy Laboratory in a one-year project to assess two important energy system models, the Baughman-Joskow Regionalized Electricity Model and the Wharton Annual Energy Model, and to identify and analyze organizational and procedural issues in the model assessment process.; Prepared for the Electric Power Research Institute, Palo Alto, CA.

‣ Independent assessment of energy policy models : two case studies

Massachusetts Institute of Technology. Model Assessment Group.
Fonte: MIT Energy Laboratory Publicador: MIT Energy Laboratory
Tipo: Relatório Formato: 13822037 bytes; application/pdf
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Energy policy models are playing an increasingly important and visible role in supporting both private and public energy policy research and decision making. As importance has increased so too has the need for model review and assessment to assist in establishing model credibility for users and those affected by model-based policy research. Toward this end EPRI has sponsored the M.I.T. Energy Laboratory in a one-year project to assess two important energy system models, the Baughman-Joskow Regionalized Electricity Model and the Wharton Annual Energy Model, and to identify and analyze organizational and procedural issues in the model assessment process.; Prepared for the Electric Power Research Institute, Palo Alto, CA.

‣ Electric power system production costing and reliability analysis including hydroelectric, storage, and time dependent power plants

Finger, Susan
Fonte: MIT Energy Laboratory Publicador: MIT Energy Laboratory
Tipo: Relatório Formato: 2399878 bytes; application/pdf
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Prepared for the U.S. Dept. of Energy under Contract no. EX-76-A-01-2295, Task order 37.

‣ Alternative electric generation impact simulator : aegis, description and examples

Gruhl, James
Fonte: MIT Energy Laboratory Publicador: MIT Energy Laboratory
Tipo: Relatório Formato: 4117344 bytes; application/pdf
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This simulator should be viewed as a framework for assembling and manipulating information about the economics, emissions, ambient concentrations, and potential health impacts of different types and configurations of electric power generating facilities. The framework is probabilistic, and thus results in several measures of the range of various consequences, in other words, a graphic display of the quality of the various predictions. The current version of the model is to be considered a testing version, as there are certain approximations implicit in some of the manipulations, scaling procedures, and the data base is incomplete in portions. As a result of additional fundings, the data base should be at the state of the art by September 1979 and additional refinements to various manipulations, in particular the economic and dispersions, should be completed by June 1980. There are, nevertheless, a tremendous number of useful exercises that can be performed on the current model version. In addition, the simulator is structured so that it is easy to improve the sophistication of certain manipulations, or to replace generic data, or update or add new data. Versions of the simulator are available so that it can be operated in batch or interactive modes.; Sponsored by the Northeast Utilities Service Company...

‣ SYSGEN : production costing and reliability model user documentation

Finger, Susan
Fonte: MIT Energy Laboratory Publicador: MIT Energy Laboratory
Tipo: Relatório Formato: 6040020 bytes; application/pdf
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"Updated February 1980".; Sponsored by the Dept. of Energy under Contract no. EX-76-A-01-2295.

‣ ELECTRA : Time dependent power generation operation model user documentation

Finger, Susan
Fonte: MIT Energy Laboratory Publicador: MIT Energy Laboratory
Tipo: Relatório Formato: 2633703 bytes; application/pdf
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Massachusetts Institute of Technology, Energy Laboratory in association with the Sloan School of Management and the Dept. of Urban Studies and Planning,1979.

‣ An environmental and economic comparison of cooling system designs for steam-electric power plants

Najjar, Kenneth F.; Shaw, John J.; Adams, E. Eric; Jirka, Gerhard H.; Harleman, Donald
Fonte: MIT Energy Laboratory Publicador: MIT Energy Laboratory
Tipo: Relatório Formato: 8009419 bytes; application/pdf
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The selection of waste heat rejection systems for steam-electric power plants involves a trade-off among environmental, energy and water conservation, and economic factors. This study compares four general types of cooling systems on the basis of these factors. The cooling systems chosen for study are: once-through systems including surface canals and submerged multiport diffusers; shallow closed cycle cooling ponds; mechanical and natural draft evaporative cooling towers; and mechanical draft dry towers. The cooling system comparison involves, first, an optimization of each cooling system and then a comparison among optimal systems. Comparison is made for an 800 MWe fossil unit and a 1200 MWe nuclear unit located at a hypothetical midwestern river site. A set of models has been developed to optimize the components of each cooling system based on the local meteorological and hydrological conditions at the site in accordance with a fixed demand, scalable plant concept. This concept allows one to compare the costs of producing the same net power from each plant/cooling system. Base case economic parameters were used to evaluate the optimum system for each of the four general cooling systems followed by a sensitivity study for each parameter. Comparison of energy and water consumption follows from the results of the performance model...

‣ Application of sector and location specific models of the "worth" of renewable energy technologies

Tabors, Richard D
Fonte: Massachusetts Institute of Technology. Energy Laboratory Publicador: Massachusetts Institute of Technology. Energy Laboratory
Tipo: Trabalho em Andamento Formato: 1194499 bytes; application/pdf
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Renewable energy sources such as solar and wind hold the potential for providing a significant portion of the U.S. energy requirements in the decades ahead. Unlike other energy sources their availability is determined by nonrandom events beyond the control of the consumer. In addition, macro-, meso-, and microclimatic conditions play a major role in determining the worth of such renewable energy sources to their owners. The worth of these new technologies will be a function of owner, location, and application as well as the traditional capital and operating cost, i.e., their worth to an owner in the southwest will be different form that to an owner in the northeast or the southeast. Dealing with energy sources, with geographic and sectorally specific energy values and with energy technologies with which we have little or no experience in the marketplace has created a set of challenges in analysis and modeling of these new technologies in competition with traditional energy technologies and with other emerging technologies. This paper will look at one simulation methodology for estimating the worth of renewable energy systems providing electricity, such as wind or solar photovoltaic power systems, and will discuss the interaction between such systems and traditional electric utilities with which they may or may not be integrated...

‣ Análise de desempenho dinâmico de sistemas de excitação para geradores síncronos em plantas de geração distribuída; Dynamic performance analisys of synchronous generators excitation systems in embedded generation power plants

Marcelo Calsan
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 21/10/2011 Português
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Nesta dissertação de Mestrado, apresenta-se um estudo detalhado sobre o desempenho dinâmico de sistemas de excitação para geradores síncronos em plantas de geração distribuída. Fora concebida uma planta e esta conectada a uma rede de distribuição com características de geração descentralizada ou distribuída. São utilizados aqui os modelos matemáticos da Norma IEEE 421.5 - IEEE DC1A, AC1A, ST1A e ST2A - e diversos estudos de estabilidade são realizados no intuito de se acompanhar o desempenho destes sistemas de excitação frente a alguns fatores como: Potência Crítica, Tempo Crítico de eliminação de Falta, níveis de curto-circuito no ponto de conexão entre as redes de distribuição e subtransmissão, relação X/R da rede e, por fim, a verificação de perfil de tensão em tomadas de carga dinâmica leve e pesada foi considerada, nas situações de operação em paralelo com a rede e operação isolada. Dados atualizados sobre os custos das diversas configurações são apresentados e em conjunto com os resultados dos estudos realizados, propõe-se qual (is) configuração (ões) pode(m) ser a(s) mais adequada(s) para plantas com esta característica de geração descentralizada; In this dissertation, a detailed dynamic performance study on excitation systems for synchronous generators in plants of Embedded Generation is presented. It's been conceived a plant and this interconnected to a distribution grid with embedded or distributed generation characteristics. IEEE 421.5 Std. mathematical models are used here: IEEE DC1A...

‣ Mathematical predictive models for cooling ponds and lakes. Part B, User's manual and applications of MITEMP. Part C. A transient analytical model for shallow cooling ponds

Octavio, Kathleen Ann Hurley; Adams, E. Eric; Koussis, Antonis D.
Fonte: MIT Energy Laboratory Publicador: MIT Energy Laboratory
Tipo: Relatório Formato: 8457389 bytes; application/pdf
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In Part B a computer code, '"MITEMP: M.I.T. Transient Temperature Prediction Model for Natural Reservoirs and Cooling Impoundments," is presented as a feasible and efficient tool for the prediction of transient performance of man-made impoundments. Particular emphasis is placed on waste heat dissipation from steam-electric power stations. The code allows the simulation of the physical regime (temperature and flow patterns) of impoundments as a function of design and for long time periods. The code contains the following elements: (1) Natural Deep Lake and Reservoir Model, (2) Deep Stratified Cooling Pond Model, (3) Shallow Vertically Mixed Dispersive Cooling Pond Model, and (4) Shallow, Vertically Mixed Recirculating Cooling Pond Model. The physical and mathematical basis for the present computer code is developed in an earlier report entitled, "Mathematical Predictive Models for Cooling Ponds and Lakes, Part A: Model Development and Design Considerations," by G. Jirka, M. Watanabe, K.H. Octavio, C. Cerco and D.R.F. Harleman, R.M. Parsons Laboratory for Water Resources and Hydrodynamics, Technical Report No. 238, December 1978. The user's manual presented herein gives a detailed description of the computational structure of MITEMP and discusses input and output requirements. The application to several case studies is presented. A complete code listing is given in the appendix...

‣ Electric generation production scheduling using a quasi-optimal sequential technique

Gruhl, Jim
Fonte: MIT Energy Lab Publicador: MIT Energy Lab
Tipo: Relatório Formato: 8983022 bytes; application/pdf
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A quasi-optimal technique ('quasi' in that the technique discards unreasonable optimums), realized by a dynamically evolving mixed integer program, is used to develop regional electric power maintenance and production schedules for a two to five year planning horizon. This sophisticated, yet computationally feasible, method is used to develop the bulk dispatch schedules required to meet electric power demands at a given reliability level while controlling the associated dollar costs and environmental impacts. The electric power system considered is a power exchange pool of closely coupled generation facilities supplying a region approximately the size of New England. Associated with a tradeoff between a given cost of production and the relevant ecological factors, an optimum production schedule is formulated which considers fossil, nuclear, hydroelectric, gas turbine and pumped storage generation facilities; power demands, reliabilities, maintenance and nuclear refueling requisites; labor coordination, geographic considerations, as well as various contracts such as interregional power exchanges, interruptible loads, gas contracts and nuclear refueling contracts. A prerequisite of the model was that it be flexible enough for use in the evaluation of the optimum system performance associated with hypothesized expansion patterns. Another requirement was that the effects of changed scheduling factors could be predicted...

‣ Hydrothermal modeling for optimum temperature control : an estimation-theoretic approach

Schrader, Bradley Philip; Moore, Stephen Fesler
Fonte: MIT Energy Lab Publicador: MIT Energy Lab
Tipo: Relatório Formato: 4716862 bytes; application/pdf
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A short-term temperature forecasting (STF) system is proposed to predict and control plant intake and discharge temperatures at Salem Harbor Electric Generating Station. It is desired to minimize receiving-water (i.e., intake-water) temperatures during peak power demand periods, in order to minimize the cost of complying with the maximum discharge water temperature limit. This study addresses the hydrothermal modeling requirements of an STF system. An important element of an STF system is a predictive model of plant intake water temperatures. For application to Salem Harbor Station, strict model performance criteria exist, defining a model development problem: Develop a simple model to predict plant intake water temperatures 24 hours ahead, predicting daily peak intake temperatures within 10F on 90% of the days, and using only existing measurements. An estimation-theoretic approach to model development is used, which quantifies and minimizes the uncertainties in the model. The approach employs optimal filtering and full-information maximum- likelihood (FIML) estimation to obtain optimum parameter estimates. A two-basin, two-layer hydrothermal model of Salem Harbor is developed. The model computes hourly intake temperatures...

‣ Assessment of light water reactor power plant cost and ultra-acceleration depreciation financing

El-Magboub, Sadek Abdulhafid.; Lanning, David D.
Fonte: MIT Energy Laboratory Publicador: MIT Energy Laboratory
Tipo: Relatório Formato: 14863046 bytes; application/pdf
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Although in many regions of the U.S. the least expensive electricity is generated from light-water reactor (LWR) plants, the fixed (capital plus operation and maintenance) cost has increased to the level where the cost plus the associated uncertainties exceed the limits deemed acceptable by most utilities. The operation and maintenance cost has increased about 25% annually during the early 1970s. The main causes are increased requirements due to safety, environmental, and security considerations. The largest improvement is co-location of units, which gives up to 37% savings in O&M cost. The rising trend of LWR capital cost is investigated. Increased plant requirements of equipment, labor, material, and time due to safety, environmental, availability, and financial considerations and due to lower productivity and public intervention are the major causes of this rising cost trend. An attempt is made to explore the elements of a comprehensive strategy for capital cost improvement. The scope of the strategy is divided into three areas. The first includes improving the current design, project management, and licensing practices. The second area, standardization, is found to reduce cost by 6 to 22% through Duplication and Reference System options. Due to lack of commercial experience...