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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

Compactação e elevação da vida útil de transformadores de distribuição empregando óleo vegetal isolante. / Reduction and extension life of distribution transformers using insulating vegetable oil.

Vasconcellos, Vagner 14 April 2016 (has links)
A busca no aumento da vida útil dos transformadores de distribuição, redução dos custos de manutenção e mitigação de falhas, leva ao desenvolvimento de novos materiais e critérios de exploração diferenciados desses ativos. Esta pesquisa apresenta o desenvolvimento de um novo transformador de distribuição compacto e mais eficiente utilizando óleo vegetal isolante totalmente biodegradável. Além de biodegradável, o óleo vegetal utilizado possui menor agressividade ambiental e maior capacidade térmica aumentando, a capacidade de carregamento do transformador sem comprometer a sua vida útil. A fim de atestar essa menor agressividade em relação ao óleo mineral, ensaios foram efetuados em um equipamento que permaneceu 12 anos em operação. O equipamento foi totalmente desmontado para análise e coleta de amostras de papel e óleo vegetal isolante. As análises visam comprovar a menor agressividade em relação ao óleo mineral, apresentadas na revisão bibliográfica. A menor agressividade torna possível a proposição de uma nova filosofia de planejamento de redes de distribuição utilizando uma quantidade menor dos novos transformadores para uma mesma carga, tornando-a mais compacta e eficiente. / The search of increase on the life expectancy of distribution transformers, reducing maintenance costs and mitigation failures, leads to the development of new materials and different operating criteria of these assets. This research presents the development of a new distribution transformer compact and more efficient with insulating in vegetable oil totally biodegradable. In addition to biodegradable, the vegetable oil used has less environmental aggressiveness and greater thermal capacity, increasing the loading capacity of the transformer without compromising its life expectancy. To prove that the vegetable oil is less aggressive than mineral oil, tests were done out in a transformer that worked for 12 years. The equipment was disassembled for analysis and collection of samples of vegetable oil and paper insulation. The analyses aim to prove the lesser aggressiveness compared to mineral oil, presented in the literature review. This situation makes it possible the proposition of a new philosophy of planning of distribution networks using a smaller amount of new transformers for the same load, making it more compact and efficient.
52

Recursos operativos no planejamento de expansão de sistemas de potência. / Operation procedures in power systems expansion planning

Magalhães, Cecilia Helena Negri de 23 March 2009 (has links)
O requisito de continuidade de fornecimento de energia elétrica tem sido crescente na medida em que a sociedade de modo geral e os processos industriais em particular apresentam forte dependência desse insumo que assegura a todos satisfação e conforto. O consumidor é um agente econômico e ele faz parte do sistema elétrico (carga). No âmbito da análise de sistemas de potência são abordados temas, desde modelos de representação da rede e da carga até conceitos de custo da continuidade e técnicas de otimização da aplicação de investimentos para priorizar aqueles que trazem maior benefício tanto para o consumidor como para o controlador da concessão. No entanto, as técnicas usuais e convencionais de Planejamento podem conduzir a soluções pouco econômicas, porquanto consideram apenas a otimização dos investimentos em obras, ou seja, reforços da rede para atender a condição normal e em emergência (critério n-1), respeitando, naturalmente, critérios técnicos (limites de tensão, sobrecargas etc). Não raro estas instalações recomendadas pela técnica convencional serem utilizadas apenas em algumas contingências, algumas com baixa probabilidade de ocorrência. Esta pesquisa desenvolve como alternativa às soluções convencionais, um modelo que considera a otimização dos investimentos, lançando mão de recursos operativos como: corte de carga, despacho ou modificações topológicas por meio de chaveamentos, quando operando em contingência. O modelo proposto prevê que a representação da geração inclua funções que relacionam a intensidade de despacho com seus custos, bem como funções que associam custo à intensidade e duração do corte de carga a cada barra do sistema. O modelo também permite a reconfiguração da rede quando operando em contingências, por meio de alterações do estado das chaves, mudando a topologia. As funções de custo do corte de carga também são modeladas neste trabalho, considerando métodos analíticos e agregados para o cálculo do prejuízo sócio-econômico resultante da interrupção. A busca da solução ótima, que pode envolver corte de carga, despachos de geração e reconfiguração da rede, substituindo reforços realizados por obra, é obtida por um algoritmo genético evolutivo. Os procedimentos do modelo proposto representam um avanço do processo de planejamento convencional, porquanto introduz a componente continuidade de serviço de forma quantitativa, caracterizando o atendimento dos requisitos de sensibilidade das cargas de cada barra do sistema, lançando mão de recursos operativos, através de possíveis despachos e alterações topológicas. Um estudo de caso ilustra a aplicação do modelo proposto. / The need for reliable electrical energy supply continuity, the industrial demand and its dependence has been growing worldwide. Besides, it also concerns society and assures satisfaction and comfort of consumers. The consumer is the economic agent since he takes part in the system. On analyzing an electrical system, models are needed to represent the network and the load and optimization frameworks in order to make better investments and prioritize those which can benefit the consumer and the concession holder. The usual Planning Models commonly provide us with uneconomical solutions since the optimization is carried out through active investments or network reinforcements to attend the normal and the emergency condition (n-1 criteria), based on technical criteria, like voltage and overload . Frequently, these techniques recommended by the conventional analysis can be applied only in some contingencies, some of them with a small probability of occurrence.. This research develops an alternative to the conventional solutions, considering the investment optimization and using operative resources, such as: load shedding, generation rescheduling or network change operation (circuit breaker, e.g.) when operating in contingency. In this model, the generation is represented by a function that relates the intensity rescheduling and its costs and functions that relates load shedding cost, the intensity and duration of curtailment on each system bus. The model sets a network contingency reconfiguration, changing the circuit break situation (open or closed) and altering the topology. The calculation of cost of load discontinuity or social cost functions (damage cost) is shown in this thesis, considering analytical and aggregating methods. The search for an optimized solution can involve load shedding, generation rescheduling and topology changes as substitutes for network reinforcements, and may be obtained by genetic- evolutive algorithm. The procedures of the proposed model represent an advancement over the conventional Planning Process as it introduces, quantitatively, the consumer service continuity, meeting the sensibility criteria of the load characterization of each consumer class connected to the system bus, through operative resources, rescheduling, load shedding and topology changes. A case study illustrates the application of the proposed model.
53

Analýza procesů ve společnosti AiP Safe s.r.o. / Process analysis in AiP Safe, Ltd.

Chovítek, Jakub January 2011 (has links)
The subject of the thesis is an process analysis in the company AiP Safe, Ltd. First, theoretical approaches and methods for organization and business process analysis are summarized. The best known modeling notations are also described. For the analysis of AiP Safe, Ltd. was chosen BSP method and for process modeling was chosen BPMN notation. The result of the work is a suggestion to establish strategic goals and strategies to achieve them, change in the organizational structure, optimization of selected processes, introduction of new metrics, introduction of new information system and recommendations based on the SWOT analysis.
54

O impacto da insuficiência no fornecimento de energia elétrica nas empresas brasileiras do setor de telecomunicações. / The economic impact of the power supply insufficiency on Brazilian telecommunication companies.

Agnes Bess D\'Alcantara e Amaral 29 March 2017 (has links)
O sistema elétrico brasileiro utiliza o custo do déficit como parâmetro no seu planejamento da expansão e operação para indicar o custo econômico da escassez de energia elétrica para a sociedade. Para o desenvolvimento de um método confiável de cálculo deste parâmetro, é importante compreender a dependência do suprimento de energia nos diversos setores econômicos. Este trabalho apresenta e discute a percepção das empresas do setor de telecomunicações dos impactos resultantes de restrições no fornecimento de energia elétrica. O trabalho foi desenvolvido em duas etapas: revisão da literatura referente aos métodos utilizados para o cálculo do custo do déficit no modelo brasileiro e na experiência internacional e, em seguida, pesquisa empírica com realização de estudos de casos em duas empresas de telecomunicações. As informações obtidas mostram que, no setor de serviços de telecomunicações, qualquer nível de interrupção ou restrição de energia tem impacto econômico para as empresas. Tendo em vista o caráter de serviço essencial para a população, as empresas investem em estruturas de contingenciamento que mitigam os riscos em caso de pequenas restrições ou interrupções curtas de energia. Indisponibilidade de energia acima da capacidade de contingenciamento prevista pelas empresas requer investimentos adicionais e implica em aumento dos custos operacionais para redução dos riscos de falhas na prestação dos serviços e suas consequentes sanções regulatórias. Em relação aos métodos para o cálculo do custo do déficit, concluiu-se que, baseado nas análises dos casos estudados, no perfil de consumo de energia e nas características de negócio do setor de telecomunicações, para pesquisas diretas ao consumidor, o método de preferência revelada é o mais adequado para este setor econômico e possivelmente outros com as mesmas características. Neste método o custo da insuficiência de energia é inferido através das decisões de investimento feitas pelo consumidor em equipamentos de contingência, tais como geradores de reserva. / The Brazilian electricity system uses the deficit cost as a parameter in its planning processes to indicate the economic cost for the society of electricity shortages. In developing a reliable method of calculating this parameter, it is important to understand the dependence of different economic sectors on the energy supply. This work presents and discusses the telecommunication companies\' perception of the impacts resulting from restrictions to the power supply. It was developed in two stages: a literature review on the methods used to calculate the deficit cost in Brazil and other countries, followed by an empirical research with case studies in two telecommunication companies. The research showed that for the telecommunication service providers, any level of power interruption or restriction has an economic impact. In view of the essential nature of the service to the population, companies invest in contingency structures to mitigate the risks for small power restrictions and short interruptions. Providing mitigation measures for larger levels of power shortage would require additional investments and result in higher operational costs, in order to decrease the risk of service interruption and consequent regulatory sanctions. Regarding the deficit cost calculation method, it is shown, based on the case studies analysis, the power consumption profile, and the business characteristics, that for consumer surveys, the revealed preference method is most suitable for the telecommunications economic sector, and possibly for other similar ones. In this method, the power shortage cost is inferred from the investment decisions made by the company in power contingency equipment, such as backup generators.
55

Recursos operativos no planejamento de expansão de sistemas de potência. / Operation procedures in power systems expansion planning

Cecilia Helena Negri de Magalhães 23 March 2009 (has links)
O requisito de continuidade de fornecimento de energia elétrica tem sido crescente na medida em que a sociedade de modo geral e os processos industriais em particular apresentam forte dependência desse insumo que assegura a todos satisfação e conforto. O consumidor é um agente econômico e ele faz parte do sistema elétrico (carga). No âmbito da análise de sistemas de potência são abordados temas, desde modelos de representação da rede e da carga até conceitos de custo da continuidade e técnicas de otimização da aplicação de investimentos para priorizar aqueles que trazem maior benefício tanto para o consumidor como para o controlador da concessão. No entanto, as técnicas usuais e convencionais de Planejamento podem conduzir a soluções pouco econômicas, porquanto consideram apenas a otimização dos investimentos em obras, ou seja, reforços da rede para atender a condição normal e em emergência (critério n-1), respeitando, naturalmente, critérios técnicos (limites de tensão, sobrecargas etc). Não raro estas instalações recomendadas pela técnica convencional serem utilizadas apenas em algumas contingências, algumas com baixa probabilidade de ocorrência. Esta pesquisa desenvolve como alternativa às soluções convencionais, um modelo que considera a otimização dos investimentos, lançando mão de recursos operativos como: corte de carga, despacho ou modificações topológicas por meio de chaveamentos, quando operando em contingência. O modelo proposto prevê que a representação da geração inclua funções que relacionam a intensidade de despacho com seus custos, bem como funções que associam custo à intensidade e duração do corte de carga a cada barra do sistema. O modelo também permite a reconfiguração da rede quando operando em contingências, por meio de alterações do estado das chaves, mudando a topologia. As funções de custo do corte de carga também são modeladas neste trabalho, considerando métodos analíticos e agregados para o cálculo do prejuízo sócio-econômico resultante da interrupção. A busca da solução ótima, que pode envolver corte de carga, despachos de geração e reconfiguração da rede, substituindo reforços realizados por obra, é obtida por um algoritmo genético evolutivo. Os procedimentos do modelo proposto representam um avanço do processo de planejamento convencional, porquanto introduz a componente continuidade de serviço de forma quantitativa, caracterizando o atendimento dos requisitos de sensibilidade das cargas de cada barra do sistema, lançando mão de recursos operativos, através de possíveis despachos e alterações topológicas. Um estudo de caso ilustra a aplicação do modelo proposto. / The need for reliable electrical energy supply continuity, the industrial demand and its dependence has been growing worldwide. Besides, it also concerns society and assures satisfaction and comfort of consumers. The consumer is the economic agent since he takes part in the system. On analyzing an electrical system, models are needed to represent the network and the load and optimization frameworks in order to make better investments and prioritize those which can benefit the consumer and the concession holder. The usual Planning Models commonly provide us with uneconomical solutions since the optimization is carried out through active investments or network reinforcements to attend the normal and the emergency condition (n-1 criteria), based on technical criteria, like voltage and overload . Frequently, these techniques recommended by the conventional analysis can be applied only in some contingencies, some of them with a small probability of occurrence.. This research develops an alternative to the conventional solutions, considering the investment optimization and using operative resources, such as: load shedding, generation rescheduling or network change operation (circuit breaker, e.g.) when operating in contingency. In this model, the generation is represented by a function that relates the intensity rescheduling and its costs and functions that relates load shedding cost, the intensity and duration of curtailment on each system bus. The model sets a network contingency reconfiguration, changing the circuit break situation (open or closed) and altering the topology. The calculation of cost of load discontinuity or social cost functions (damage cost) is shown in this thesis, considering analytical and aggregating methods. The search for an optimized solution can involve load shedding, generation rescheduling and topology changes as substitutes for network reinforcements, and may be obtained by genetic- evolutive algorithm. The procedures of the proposed model represent an advancement over the conventional Planning Process as it introduces, quantitatively, the consumer service continuity, meeting the sensibility criteria of the load characterization of each consumer class connected to the system bus, through operative resources, rescheduling, load shedding and topology changes. A case study illustrates the application of the proposed model.
56

Cálculo da taxa de crescimento da tensão de restabelecimento transitória. / Rate of rise of transient recovery voltage calculation.

Patricia de Oliveira Preto 22 March 2017 (has links)
Esta dissertação aborda o cálculo da taxa de crescimento da tensão de restabelecimento transitória (TCTRT), considerando o caso de falha na barra, durante a abertura do primeiro polo e o cálculo da tensão de restabelecimento transitória (TRT) nos primeiros instantes de tempo, incluindo o efeito da capacitância. Os principais casos possíveis de falha na barra foram analisados e os resultados demonstraram a precisão das expressões obtidas. Normalmente, o cálculo da TCTRT e da TRT é feito por meio de simulações em programas de transitórios eletromagnéticos em que há rotinas específicas para a extração dos valores destas, porém, em determinadas condições, podem ocorrer oscilações ou imprecisões numéricas. Por ser um assunto de grande interesse convém desenvolver expressões que possam esclarecer resultados duvidosos sem a necessidade de artifícios de redução do passo de integração a valores muitas vezes não factíveis. As expressões obtidas neste trabalho podem ser utilizadas não só para se obter de forma precisa e simplificada os valores da taxa de crescimento da tensão de restabelecimento transitória de um circuito real, assim como os valores da TRT nos primeiros instantes de tempo. / This study is focused on the rate of rise of transient recovery voltage (RRTRV) calculation considering the case of bus fault, during the first pole to open, and also includes the transient recovery voltage (TRV) calculation, in the first instants of time, including the capacitance effect. The main cases of bus fault have been evaluated and demonstrate that the expressions developed in this study are relevant and with good precision. Usually, the RRTRV and the TRV are calculated with the use of simulation programs, using specific routines, nevertheless, in certain conditions, there might be oscillations and numeric imprecisions which requires a mathematic expression. This topic is of great interest and it is important to have mathematical expressions that could clarify doubtful results. The expressions obtained in this study can be use in a very simples and effective mode to calculate RRTRV and the TRV in the first instants of time, considering a real life circuit.
57

Algoritmo especializado aplicado ao planejamento da expansão de redes aéreas de sistemas de distribuição / Specialized algorithm applied to planning the expansion of overhead power lines of distribution systems

Mendonça, Willian Douglas Ferrari 04 July 2014 (has links)
Made available in DSpace on 2017-07-10T17:11:48Z (GMT). No. of bitstreams: 1 Dissertacao Willian Douglas F Mendonca.pdf: 2130607 bytes, checksum: ef5e681d6a8d26e8c6fe5324e3cf0c03 (MD5) Previous issue date: 2014-07-04 / In this Master's Dissertation is presented the development of a specialized algorithm for planning the expansion of pole networks of distribution systems. The technique used for solution is the Constructive Heuristics that has been used together with mathematical optimization models to solve the problem. However the presented algorithm does not employ a mathematical optimization model, in other words, a model compound of objective function and constraints. So, instead of working with variables, we seek to work with parameters, with the objective of providing greater speed to the research process, simplifying the search process for the final topology always keeping committed to finding a solution of good quality. Despite not having a guarantee that the solution is the global optimum, the solutions obtained by this type of algorithm solutions are almost always of excellent quality and can be used as a starting point for algorithms that use techniques or more complex mathematical models. To assist the Constructive Heuristic Algorithm in the search for the final topology is used a specialized routine for the calculation of AC power flow The methodology used by the subroutine for these calculations is based on the Backward Forward Sweep algorithm. / No presente trabalho é apresentado o desenvolvimento de um algoritmo especializado para o planejamento da expansão de redes aéreas de sistemas de distribuição. A técnica utilizada para solução é a Heurística Construtiva que tem sido utilizada em conjunto com modelos matemáticos de otimização para resolver o problema. No entanto o algoritmo apresentado não emprega um modelo matemático de otimização, em outras palavras, um modelo composto de função objetivo e restrições. Assim, em vez de trabalhar com variáveis, procura-se trabalhar com parâmetros, com o objetivo de proporcionar uma maior velocidade ao processo de pesquisa, simplificando o processo de busca para a topologia final sempre buscando manter o compromisso de encontrar uma solução de boa qualidade. Apesar de não ter a garantia de que a solução seja a ótima global, as soluções obtidas por este tipo de algoritmo são quase sempre soluções de excelente qualidade e podem ser usadas como ponto de partida para os algoritmos que usam técnicas ou modelos matemáticos mais complexos. Para auxiliar o Algoritmo Heurístico Construtivo na busca para a topologia final é usada uma rotina especializada para o cálculo do fluxo de potência CA. A metodologia utilizada pela subrotina para estes cálculos está baseada no algoritmo de varredura Backward Forward Sweep.
58

Usinas hidrelétricas \'botox\': aspectos regulatórios e financeiros nos leilões de energia / Hydroelectric power plants named \"Botox\": regulatory and financial issues in electric energy auctions

Rego, Erik Eduardo 21 November 2007 (has links)
Este trabalho tem o objetivo de relatar e analisar a história dos projetos hidrelétricos conhecidos por \"botox\" (expressão cunhada aos projetos mais velhos com roupagem de novos), desde sua origem, ainda na primeira reforma do setor elétrico brasileiro em 1998, até seu desfecho, no leilão de energia nova de 2007, já no âmbito da segunda reforma do setor elétrico iniciada em 2004. Para sua total compreensão, é feita a historiografia do setor elétrico desde o Código de Águas, vis-à-vis da política econômica mundial e de seus reflexos na economia nacional. A dissertação prossegue com a descrição das alterações regulatórias, principalmente no que se refere ao critério de licitação de concessões de aproveitamentos hidrelétricos, caracterizando e identificando como se formou essa categoria de empreendimentos \"botox\". Após a conceituação teórica de leilões, são analisadas as participações desse tipo de projeto nos cinco leilões de energia nova, ocorridos entre 2005 e 2007. Além de uma abordagem sob o ponto de vista do produtor independente de energia elétrica, também é feita análise de que forma a alteração da regulamentação para outorga de concessões de geração e para comercialização de energia modificou a perspectiva de evolução do valor da energia elétrica para os autoprodutores. Por fim, é feita breve discussão sobre o processo de licenciamento ambiental desses projetos, com ênfase em seus aspectos regulatórios. / This thesis aims to discuss and analyze the history of a particularly hydroelectric power plants group, nicknamed as \"botox\". This expression comes from the fact that those projects were old ones, which have been previously conceived, that were treated as brand new by the Brazilian regulatory framework. Its history has began from the Brazilian electricity industry reform in the 1990s. This history reaches its final step in the 2007 auction, already under the revised power sector model launched in 2004, which marked the last opportunity of the so-called \"botox\" projects to participate closing deals to sell long term energy in a specially designed auction. To perform this analysis, it is firstly reported the context were the \"botox\" were conceived in the recent history of Brazilin Electricity Sector, and how power plants group was impacted by the shifts of international economic trends. The next section discusses the last two power sector reforms, particularly addressing the shifts hydro-plants investors faced on having access to concession auctions for new projects. After providing the background of the auction mechanism theory, it is examined the newly designed electricity auction adopted in Brazil as well as the results of the auctions that took place between 2004 up to 2007. Finally, it is discussed implications of the rules regarding the latest industry reform and regulatory issues towards environmental licenses, focusing on their impacts on the willingness to invest of self-generators owners of \"botox\" projects.
59

Planejamento da evolução de sistemas de tecnologia da informação: estudo de casos múltiplos em empresas de manufatura. / Planning the evolution of information technology systems: multiple-case study in manufacturing companies.

Hikage, Oswaldo Keiji 15 February 2011 (has links)
A constante evolução dos Sistemas de Informação (SI) tem levado os profissionais dessa área a se defrontarem com vários problemas relativos a tomadas de decisões quando se vêem diante da necessidade de planejar uma atualização ou evolução de seus sistemas de tecnologia da informação. Dentre as dúvidas e dilemas que os administradores se deparam cotidianamente se referem a como e para qual sistema evoluir, escolha de opções entre adquirir soluções prontas, desenvolver seu próprio sistema, modificar ou customizar, transformar um software pronto em outro aplicativo que atenda às necessidades da empresa. Por isso torna-se importante compreender como as organizações se preparam diante dessas dificuldades e o que existe de conhecimento nessa área que possa servir de orientação diante dessas várias perspectivas. Esta pesquisa aborda, dentro dos Sistemas de Tecnologia da Informação, os aspectos referentes aos Sistemas de Informação relacionados às aplicações na organização, sem contudo, envolver a infra-estrutura, hardware, comunicação, automação e redes. Tendo como objetivo entender como as organizações planejam a evolução de seus sistemas de informação, esta pesquisa foi realizada por meio de estudo de casos múltiplos em seis empresas de manufatura, procurando descrever e analisar como elas tratam essa questão obtendo-se como resultado uma compreensão de que a maioria delas pouco utiliza uma metodologia de planejamento. Adicionalmente obteve-se um levantamento das boas práticas em planejamento como contribuição para a evolução dos sistemas de tecnologia da informação. / The constant evolution of Information Systems (IS) has been leading professionals in this area to face several problems concerning the decision making when they have to plan an upgrade or evolve their technology information system. Among the questions and dilemmas that administrators face daily are how and for what systems to evolve, having to decide between purchasing ready-made solutions, develop their own system, modify, customize or transform into another software application that meets the needs of company. Therefore it is important to understand how organizations face these difficulties and to verify the knowledge related to this question that cans guide the decision facing these various perspectives. This research addresses within the information technology systems aspects about information systems related to applications into the organization, however, without involving infrastructure, hardware, communication, automation and networking. Through multiple-case study in six manufacturing companies seeks to assess how they plan the evolution of their information technology systems. As a result, this study concludes that organizations rarely plan the evolution of the systems. Additionally is presented a roll of best practices in planning the evolution of systems.
60

Rational Supply Planning In Resource Constrained Electricity Systems

Balachandra, P 12 1900 (has links)
Electricity is the most preferred source of energy, because of its quality and convenience of usage. It is probably one of the most vital infrastructural inputs for economic development of a country. Indeed it is the fulcrum which can leverage the future pace of growth and development. These reasons have made the electric power industry one of the fastest growing sectors in most developing countries and particularly in India. Therefore it is not surprising to observe the economic growth of a country being related to the increase in electricity consumption. In India, the growth rate of demand for power is generally higher than that of Gross Domestic Product (GDP). However, to achieve this kind of growth in electricity supply, the capital investments required are very huge. Even though the electricity sector generally gels a major share in the budgetary allocations in India, this is inadequate to add the required quantum of new generation capacity to keep pace with the increase in demand for electricity. Additional constraints like capital scarcity in the public sector, lack of enthusiasm among the private and foreign investors, and strong opposition from the environmentalists have further contributed to this slow pace of new generating capacity addition. This has resulted in severely constrained systems in India. The main focus of the present research work is on the development of an integrated approach for electricity planning using a mathematical modeling framework in (he context of resource constrained systems. There are very few attempts in the literature to integrate short, medium and long term issues in electricity planning. This is understandable from the point of view of unconstrained electricity systems where this type of integration is unnecessary since such systems have a luxury of surplus capacity to meet the current demand and capacity additions are required only for meeting predicted future increase in demand. However, in the case of constrained electricity systems, which are characterized by shortages, this kind of integration is very essential. These systems have to manage with inadequate capacity in the present, plan capacity additions to bridge the existing gap and to meet future increase in demand, and always explore the possibility of adding capacity with short gestation period. The integrated approach is expected to achieve effective supply-demand matching on a continuous basis encompassing both the short term and long term horizons. To achieve this, we have considered three alternatives- existing supply, new supply and non-supply (rationing) of electricity. The electricity system of the state of Karnataka, which is severely constrained by both limited capital and energy resources, has been selected for this purpose. As a first step, the supply and demand situation has been studied in the context of resource constraints. In terms of supply, both existing and future additions are studied in detail with respect to the potential created, generation types, import potential, technical constraints, energy and power shortages, planned and proposed capacity additions by both public and private sectors, etc. The demand patterns have been studied by introducing a new concept of "Representative Load Curves (RLCs)". These RLCs are used to model the temporal and structural variations in demand for electricity. Also, appropriate non-supply options (rationing measures) for effective management of shortages are identified. Incorporating this information, an integrated mathematical model, which is expected to generate a target plan for a detailed generation scheduling exercises and a requirement plan for a regular generation expansion planning, has been developed. The other important alternative "Demand-Side-Management (DSM)", which could be considered as an effective option to achieve efficient supply-demand matching has not been included in the present research work. The major reason for not including the DSM alternatives is due to the difficulty in integrating these in the modelling approach adopted here. In the present approach we have used typical daily load curves (RLCs) to represent the demand for electricity. These are aggregate load curves and do not contain any sector-wise or end-use-wisc details. On the other hand, DSM alternatives are end-use focused. To incorporate DSM alternatives, we should have information on end-usc-wisc power demand (kW or MW), savings potential, time-of-use, etc. For this purpose it may be required to have end-use-wisc daily load curves. This information is not available and a separate detailed survey may be required to generate these load curves. This, we felt, is out of the scope of this present research work and a separate study may be required to do this. Therefore, we restricted our focus to supply planning alone. A detailed literature review is conducted to understand different types of modeling approaches to electricity planning. For the present study, however, the review of literature has been restricted to the methods of generation expansion planning and scheduling. In doing so, we attempted to bring out the differences in various approaches in terms of solution methods adopted, alternatives included and modifications suggested. Also, we briefly reviewed the literature on models for power and energy rationing, because management of shortages is an important aspect of the present study. Subsequently, a separate section is devoted to present an overview of the non-supply of electricity and its economic impacts on the consumers. We found that the low reliability of the electrical system is an indicator of the existence of severe shortages of power and energy, which cause non-supply of electricity to the consumers. The overview also presented a discussion on reasons for non-supply of electricity, and the types of non-supply options the utilities adopt to over come these shortages. We also attempted to explain what we mean by non-supply of electricity, what are its cost implications, and the methods available in the literature to estimate these costs. The first objective of the research pertains to the development of a new approach to model the varying demand for electricity. Using the concept of Representative Load Curves (RLCs) we model the hourly demand for a period of four years, 1993-94, 1994-95, 1995-96 and 1996-97, to understand the demand patterns of both unconstrained and constrained years. Multiple discriminant analysis has been used to cluster the 365 load curves into nine RLCs for each of the four years. The results show that these RLCs adequately model the variations in demand and bring out the distinctions in the demand patterns existed during the unconstrained and constrained years. The demand analysis using RLCs helped to study the differences in demand patterns with and without constraints, impacts of constraints on preferred pattern of electricity consumption, success of non-supply options in both reducing the demand levels and greatly disturbing the electricity usage patterns. Multifactor ANOVA analyses are performed to quantify the statistical significance of the ability of the logically obtained factors in explaining the overall variations in demand. The results of the ANOVA analysis clearly showed that the considered factors accounted for maximum variations in demand at very high significance levels. It also brought out the significant influence of rationing measures in explaining the variations in demand during the constrained years. Concerning the second objective, we explained in detail, the development of an integrated mixed integer-programming model, which we felt is appropriate for planning in the case of resource constrained electricity systems. Two types of integrations are attempted (i) existing supply, non-supply and new supply options for dynamically matching supply and demand, (ii) operational and strategic planning in terms of providing target plans for the former and requirement plans for the latter. Broadly, the approach addresses the effective management of existing capacity, optimal rationing plan to effectively manage shortages and rationally decide on the new capacity additions both to bridge the existing gap between supply and demand, and to meet the future increases in demand. There is also an attempt to arrive at an optimal mix of public and private capacity additions for a given situation. Finally, it has been attempted to verify the possibility of integration of captive generation capacity with the grid. Further, we discussed in detail about the data required for the model implementation. The model is validated through the development of a number of scenarios for the state of Karnataka. The base case scenario analyses are carried out for both the unconstrained and constrained years to compare the optimal allocations with actual allocations that were observed, and to find out how sensitive are the results for any change in the values of various parameters. For the constrained years, a few more scenarios are used to compare the optimal practice of managing shortages with to what has been actually followed by the utility. The optimal allocations of the predicted demand to various existing supply and non-supply options clearly showed that the actual practice, reflected by the actual RLCs, are highly ad hoc and sub-optimal. The unit cost comparisons among different scenarios show that the least cost choice of options by the utility does not necessarily lead to good choices from the consumers’ perspective. Further, a number of future scenarios are developed to verify the ability of the model to achieve the overall objective of supply-demand matching both in the short and long term. For this purpose both the short horizon annual scenarios (1997-98 to 2000-01) and long horizon terminal year scenarios (2005-06 and 2010-11) are developed assuming capacity additions from only public sector. Overall, the results indicated that with marginal contributions from non-supply options and if the public sector generates enough resources to add the required capacity, optimal matching of supply and demand could be achieved. The scenario analyses also showed that it is more economical to have some level of planned rationing compared to having a more reliable system. The quantum of new capacity additions required and the level of investments associated with it clearly indicated the urgent need of private sector participation in capacity additions. Finally, we made an attempt to verify the applicability of the integrated model to analyse the implications of private sector participation in capacity additions. First, a number of scenarios are developed to study the optimal allocations of predicted hourly demand to private capacity under different situations. Secondly, the impacts of privatisation on the public utility and consumers are analysed. Both short term and long term scenarios are developed for this purpose. The results showed the advantage of marginal non-supply of electricity both in terms of achieving overall effective supply-demand matching and economic benefits that could be generated through cost savings. The results also showed the negative impacts of high guarantees offered to the private sector in terms of the opportunity costs of reduced utilization of both the existing and new public capacity. The estimates of unit cost of supply and effective cost of supply facilitated the relative comparison among various scenarios as well as finding out the merits and demerits of guarantees to private sector and non-supply of electricity. The unit cost estimates are also found to be useful in studying the relative increase in electricity prices for consumers on account of privatization, guarantees and reliable supply of electricity. Using the results of scenario analyses, likely generation expansion plans till the year 2010-11 are generated. The analyses have been useful in providing insights into fixing the availability and plant load factors for the private sector capacity. Based on the analysis, the recommended range for plant utilization factor is 72.88 - 80.57%. The estimated generation losses and the associated economic impacts of backing down of existing and new public capacity on account of guarantees offered to private sector are found to be significantly high. The analyses also showed that the backing down might take place mainly during nights and low demand periods of monsoon and winter seasons. Other impacts of privatization that studied are in terms of increased number of alternatives for the utility to buy electricity for distribution and the associated increase in its cost of purchase. Regarding the consumers, the major impact could be in terms of significant increase in expected tariffs. The major contributions of this thesis are summarized as follows: i. An integrated approach to electricity planning that is reported here, is unique in the sense that it considers options available under various alternatives, namely, existing supply, non-supply and new supply. This approach is most suited for severely constrained systems having to manage with both energy and capital resource shortages. ii. The integration of operational and strategic planning with coherent target plans for the former and requirement plans for the latter bridges the prevailing gap in electricity planning approaches. iii. The concept of Representative Load Curves (RLCs), which is introduced here, captures the hourly, daily and seasonal variations in demand. Together, all the RLCs developed for a given year are expected to model the hourly demand patterns of that year. These RLCs are useful for planning in resource constrained electricity systems and in situations where it is required to know the time variations in demand (e.g. supply-demand matching, seasonal scheduling of hydro plants and maintenance scheduling). RLCs are also useful in identifying the factors influencing variations in demand. This approach will overcome the limitations of current method of representation in the form of static and aggregate annual load duration curves. iv. A new term, "non-supply of electricity" has been introduced in this thesis. A brief overview of non-supply presented here includes reasons for non-supply, type of non-supply, methods to estimate cost of non-supply and factors influencing these estimates. v. The integrated mixed integer programming model developed in the study has been demonstrated as a planning tool for- • Optimal hourly and seasonal scheduling of various existing supply, non-supply and new supply options • Estimation of supply shortages on a representative hourly basis using the information on resource constraints • Effectively planning non-supply of electricity through appropriate power/energy rationing methods • Estimation of the need for the new capacity additions both to bridge the existing gap and to take care of increase in future demand levels • Optimal filling of gaps between demand and supply on a representative hourly basis through new supply of electricity • Optimally arriving at the judicious mix of public and private capacity additions • Studying the impacts of private capacity on the existing and new public sector capacity, and on the consumers • Optimally verifying the feasibility of integrating the captive generation with the total system vi. The demand analysis using RLCs helped to bring out the differences in demand patterns with and without constraints, impacts of constraints on preferred pattern of electricity consumption, success of non-supply options in both reducing the demand levels and greatly disturbing the electricity usage patterns. Multifactor ANOVA analyses results showed that the logically obtained factors accounted for maximum variations in demand at very high significance levels. vii. A comparison of optimal (represented by optimal predicted RLCs) and actual (reflected by actual RLCs) practices facilitated by the model showed that the actual practice during constrained years is highly ad hoc and sub-optimal. viii. The results of the scenario analyses showed that it is more economical to have some amount of planned rationing compared to having a more reliable system, which does not allow non-supply of electricity. ix. The scenarios, which analysed the impacts of high guarantees offered to the private sector, showed the negative impacts of these in terms of reduced utilization of both the existing and new public capacity. x. Generation expansion plans till the year 2010-11 are developed using the results of various kinds of scenario analyses. Two groups of year-wise generation expansion plans are generated, one with only public sector capacity additions and the other with private sector participation. xi. The impacts of privatization of capacity additions are studied from the point of view of the utility and consumers in terms of expected increase in cost of purchase of electricity and tariffs. xii. The analyses are also made for developing some insights into fixing the availability and plant load factors for the private capacity. Based on the analysis, the recommended range for plant utilization factor is 72.88 - 80.57%. We believe that the integrated approach presented and the results obtained in this thesis would help utilities (both suppliers and distributors of electricity) and governments in making rational choices in the context of resource constrained systems. The results reported here may also be used towards rationalization of Government policies vis-a-vis tariff structures in the supply of electricity, planning new generation capacity additions and effective rationing of electricity. It is also hoped that the fresh approach adopted in this thesis would attract further investigations in future research on resource constrained systems.

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