No início dos anos 80, vericou-se um enorme excedente de energia elétrica que possibilitou a implementação de um programa de substituição de energéticos importados por eletricidade. Considerando a energia elétrica como um fator de desenvolvimento é importante que as previsões de consumo de energia, atendam os interesses da sociedade como um todo. A origem dos excedentes verificados foi identificada após estudos e análises dos Planos de Atendimento aos Requisitos de Energia\", desenvolvidos a partir da segunda metade da década de 60 até o nal da década de 70 e de sua contextualização econômica. A energia elétrica foi uma opção vantajosa para os consumidores de derivados de petróleo e oportuna para o País. Contudo, o atendimento de novas cargas não previstas pelo setor elétrico refletiu nos sistemas, obrigando as concessionárias de energia a antecipar os investimentos em distribuição e transmissão. A ampliação do mercado de energia. possibilitada pela comercialização dos excedentes, foi induzida por uma decisão política de elevar os preços dos derivados de petróleo e flexibilizar a comercialização da energia excedente através de tarifas especiais. / A signicant excess of electrical energy, veried on the early nineteen eightie, allowed the implementation of an imported energy substitution program. Considering electrical energy as an important factor for development it is important to have global requisites planning for all society. The origin of the excess of electrical energy, veried in early eighties, was found after study and analyses of the Plans Requirements of Energy in the seventies years and the Government Plans for those years. The electrical energy was a good option for both the consumers and the Government, but it was not as good for the energy concessionaires because the prices dened for generation, transmission and distribution were very low. The expansion of electrical energy consumption was induced by the effect of the combined political decision to substantially raise the prices of oil derivatives and flexibilization of the electrical energy commercialization excess through special tariffs.

O presente trabalho de pesquisa foi desenvolvido tendo por objetivo estudar e verificar o comportamento da produção de energia elétrica por sistemas de cogeração em duas indústrias de processamento de cana-de-açúcar. As indústrias objeto do estudo situam-se ambas na região Norte do Estado de São Paulo, onde foram coletados dados de cana moída, energia adquirida da concessionária, energia autogerada, potencia média gerada, consumo específico e produção de bagaço referentes ao período 1990-1997. Corn as séries de variáveis, foram elaboradas tabelas resumidas das médias, medianas e desvio-padrão mensais, corn objetivo de se avaliar o comportamento dessas variáveis ao longo das safras, bem como se observar as tendências delineadas pelos dados. O ajustamento de regressão permitiu inferir o grau de aderência dos dados coletados a modelos matemáticos, e a partir destes, verificar o desempenho das duas indústrias em termos de produtividade e viabilidade de produção de energia elétrica excedente. Os resultados obtidos mostram que das duas usinas estudadas, a Usina A praticamente manteve estável os níveis de produção durante todo período de estudo, enquanto a Usina B apresentou um crescimento na produção industrial da ordem de 45% entre as safras inicial e final do estudo. / This research work was developed with the objective study and verify the behavior of the production of electricity by cogeneration systems in two industries processing cane sugar. The object of study industries are located both in the Northern region Sao Paulo, where data were collected from crushed sugarcane, commercially purchased power, self-generated energy, average power generated, specific consumption and bagasse production for the period 1990-1997. Corn sets of variables, the summary tables were prepared mean, median and standard deviation of monthly corn objective of evaluating the behavior of these variables over the crops, as well as observe the trends outlined by the data. The adjustment regression allow us to infer the degree of adherence data collected mathematical models, and from these, check the performance of two industries in terms of productivity and viability of producing electricity surplus. The results show that the two plants studied, The Plant remained practically stable production levels throughout the study period, while Plant B showed a growth in industrial production order of 45% between the initial and final harvests of the study.

No setor elétrico do Peru, o setor residencial de Lima Metropolirana apresenta um grande potencial de conservação de energia, principalmente no serviço de iluminação, além da refrigeração e o aquecimento de água, proporcionalmente pequenos, porém signicativo. Neste trabalho, estima-se o potencial acumulada de conservação de energia elétrica igual a 8:456.9 GWh, no período 1995-2005, como resultado da utilização de tecnologias eficientes no serviços de iluminação, conservação de alimentos e aquecimento de água. Os custos de energia conservada sio inferiores a US$ 0,04/kWh, ou seja, equivalem a 36% do preço de energia elétrica que paga o consumidor residencial (US$ 0,11/kWh). Com a finalidade de superar as barreiras ao uso eciente da energia elétrica no Peru, neste trabalho propõe-se diversas condições que devem estabelecer-se para desenvolver um mercado de tecnologias eficientes com o objetivo de acelerar e aumentar a penetração destas tecnologias no mercado de usos nais de energia elétrica no setor residencial de Lima metropolitana. Analisam-se condições operacionais ao nível de governo, dos fabricantes, das concessionárias e tarifas elétricas, e dos consumidores. / The residential sector in the city of Lima, Peru has a large potential for energy conservation, mainly, for lighting, refrigeration and water heating. While relatively small, savings obtained for these energy services are meaningful. In this work, we assessed a cumulated potential of 8,456.9 GWh for electricity conservation in the period 1995-2005, that might be developed through efficient technologies for residential lighting, food storage and water heatin g. The energy conservation costs are below US$ 0.04/kWh, which is equivalent to 36 percent of the residential electricity rate in Lima (US$ 0.11/kWh). In this work, we discussed some operational conditions for development of a market for energy efficient technologies and equipments that may increase the penetration of those devices for the residential electricity end-use consumption in Lima. The operational conditions for development of such a market have been considered for its four main components, i.e., the power distribution utility, the consumers, the electricity rates, the equipment manufacturers and the governments.

M.Ing. (Electrical Engineering) / This thesis primarily addresses the subject of analysis and compensation of fictitious power instantaneously: Fictitious power is defined as that component of apparent power which does not contribute to the nett transfer of energy from source to load. The dynamic characteristics of contemporary electric loads are of such orders of magnitude that the load current contains severe changes 'within a fundamental frequency cycle. Furthermore, such changes might not be periodic but may only appear for short durations. Likewise, load current unbalance may also reach intolerable levels, only for relatively short durations of time. Power theories based on the classic active current approach has the characteristic that calculated magnitudes are only available after some time has elapsed, which usually is a fundamental frequency period. The original instantaneous power theory calculates active and fictitious current magnitudes instantaneously, but these obtained values do not relate to the classic values. Classic static VAr compensator dynamic operation limits lie at switching twice per fundamental frequency cycle, with the result that intra-eycle changes in the load current cannot be compensated. Distortion compensators' comprise an energy storage element and a high frequency converter with dynamic characteristics to compensate instantaneously for fictitious power components. The revised instantaneous power theory is proposed in this thesis and is a combination of the classic active current theory and the original instantaneous power theory. The revised instantaneous power theory generates the fictitious currents instantanenously. A distortion compensator is combined in parallel with the classic static VAr compensator to obtain the hybrid fictitious power compensator. This compensator has dynamic characteristics to match the revised instantaneous power theory and to compensate for high dynamic load current variations within one fundamental cycle. The revised instantaneous power theory is implemented as primary control of a hybrid fictitious power compensator. The error modulation automatic control technique for the distortion compensator is proposed and implemented with improved results in distortion current compensation and current-fed distortion compensator stability. The secondary control of the hybrid fictitious power compensator concerns the feedback of the generated hybrid fictitious power compensator currents. The control of the hybrid fictitious power compensator is done with a personal computer in parallel with analog circuitry. The computer has an on-board dedicated data acquisition and output card. The hybrid fictitious power compensator is demonstrated on two experimental loads and the revised instantaneous power theory is demonstrated on three experimental loads.

M.Ing. (Electrical and Electronic Engineering) / Please refer to full text to view abstract.

M.Tech. (Metallurgical Engineering) / Please refer to full text to view abstract

[No abstract available] / Applied Science, Faculty of / Electrical and Computer Engineering, Department of / Graduate

The object of this thesis is to find a method for locating transient as well as permanent faults on transmission lines. Transient faults are those lasting for a fraction of a second or so which do not cause serious enough damage to necessitate immediate repairs before the line may be reenergized. However, transient faults such as insulator flashovers may cause enough damage to be a potential permanent outage. It is thus desirable to be able to locate the position of the fault, and to inspect the line and insulators so that they may be repaired if necessary when the line can be conveniently removed from service. The method that seemed most desirable was based on the echo-ranging principle such as is used in radar. This method has the advantages of accuracy and ease of interpretation. A damped sine wave pulse is generated at short intervals and fed onto the transmission line by means of a coupling capacitor. This pulse travels along the line and is partially reflected from any discontinuity such as a flashover to ground. The transmitted pulse, and pulses reflected from the end of the line and the fault are shown on a viewing tube; the distance to the fault being found by proportion. The line is pulsed only on the occurrence of a fault; thus any interference with radio is eliminated. The pulse generator is tripped by zero-sequence current or from the surge created by the fault itself. The pulses were to be recorded on a skiatron or memory tube which holds the trace on the tube until it is erased at will by the operator. This eliminates the necessity of photographic equipment and the disadvantages of delay and inconvenience of developing the film. The work accomplished on the project included the theory of wave propagation along transmission lines and the reflection to be expected for arcing ground faults. A pulse generator was built to produce either a damped sine wave or a sharp-fronted wave with exponential decay. Experiments were -carried out on coaxial cable with carbon and oil arcs as the fault, but no experiments were carried out on actual transmission lines as no line was available. The results of these experiments and the theory indicate that the method should be satisfactory on transmission lines. / Applied Science, Faculty of / Mechanical Engineering, Department of / Graduate

The new formulation of the load-flow problem presented in this thesis yields a set of equations each of which has only one nonlinear term. The equations are derived from the corrections required to make the final values equal to the initial estimated values. The resultant set of equations can be used when the initial estimated values are adjusted to their final values. However, derivation of the equations for this latter case results in a set of equations with (n-1) nonlinear terms in each equation for an n-bus power system. Five algorithms based upon the new formulation are described. Numerical tests on several sample power systems show that some of the new algorithms possess better convergence and speed characteristics than the commonly used Ward-Hale and Newton algorithms. / Applied Science, Faculty of / Electrical and Computer Engineering, Department of / Graduate

The effect of local motor loads on power system stability is investigated. The power system consists of a synchronous generator supplying a large system through a long transmission line. The loads studied are an induction motor, a synchronous motor, and the combination of the two, although a general case of any number of local induction and synchronous motor leads can be easily formulated. Stability is determined by observing the response of the generator and the motors of the system with a fault at the transmission line. The response is calculated from the mathematical model and is- also observed from tests on a dynamic power system model in the laboratory. It is found from the studies that all the local motor loads improve the stability of a power system. / Applied Science, Faculty of / Electrical and Computer Engineering, Department of / Graduate