Este trabalho desenvolve um novo método de controle de eficiência energética no acionamento de motores de indução. Esta técnica utiliza um modelo de perdas e uma estrutura de controle baseada no mínimo consumo de energia elétrica. Em um primeiro momento, são apresentados os estudos com os principais controladores de eficiência energética da última década. Depois, são apresentados os modelos elétricos e mecânicos do motor de indução trifásico, a partir do modelo clássico, com o eixo de referência qd0. O controlador utilizado, é o controle por campo orientado indireto (IFOC - Indirect Field Oriented Control), composto por uma malha externa de controle de velocidade e fluxo, e uma malha interna de controle de correntes, que demonstram um bom desempenho de torque e velocidade. Por se tratar de um controlador IFOC, onde os parâmetros do motor são fundamentais para obter bons resultados, o ensaio do motor de indução é realizado e apresentado. Sabendo-se das principais fontes de perdas do motor, o controlador de eficiência energética pode ser elaborado. O controlador baseado no modelo de perdas (LMC -Loss-Model-Based Control) é descrito, assim como o controlador de busca recursiva (SC - Search Control), ambos muito utilizados na literatura. O LMC proposto é implementado através de curvas padrão de fluxo ótimo baseado na potência absorvida, dependendo da carga no eixo do motor, uma nova curva padrão é utilizada. O controlador de eficiência proposto chamado de (MBC - Model Based Control), utiliza o método LMC com um controlador IFOC, este é simulado via software Matlab e verificado experimentalmente através de uma plataforma de acionamento projetada e montada, conforme o projeto descrito. O controlador de eficiência proposto, é comparado com o acionamento de fluxo constante e com o controlador SC, para diferentes perfis de carga no eixo. Para todos os casos o controlador proposto, apresentou o melhor rendimento da máquina. / This paper develops a new method of controlling the drive energy efficiency of induction motors . This technique uses a model of losses and a control structure based on minimum energy consumption . At first , studies with the main drivers of energy efficiency in the last decade are presented . Then the electrical and mechanical models of three-phase induction motor are presented , from the classic model , with the reference axis qd0 . The controller used is an indirect field-oriented control (IFOC), composed of an outer control loop speed and flow , and an inner current control loop , showing a good performance of torque and speed. Because it is a IFOC controller, where the engine parameters are critical to obtain good results , the testing of induction motor is carried out and presented . Knowing the main sources of losses of the engine, the controller of energy efficiency can be drawn . The loss model based (LMC) controller is described , as well as the controller recursive search (SC), both widely used in the literature . The LMC proposed is implemented through optimum standard curves of flow based on power absorbed. Depending on the load on the motor shaft , a new standard curve is used . The proposed controller called efficiency ( MBC - Model Based Control ) uses the LMC method with a IFOC controller , this is simulated via textit software emph Matlab and verified experimentally through a platform drive designed and assembled , as the project described . The controller proposed efficiency is compared with the drive and the constant flow controller SC to different profiles of the axle. For all cases, the proposed controller showed the best performance of the machine.

Esta pesquisa tem por objetivo efetuar uma investigação acerca da eficiência energética nas indústrias, com foco na identificação dos potenciais de conservação de energia e possíveis barreiras para se implantar um sistema de gestão de energia, tendo como principais motivações o lançamento do Plano Nacional de Eficiência Energética (PNEf), que prevê uma grande economia de energia para os próximos anos, e da norma ABNT NBR ISO 50001- Sistema de gestão de energia. Num primeiro instante, fez-se um estudo dos principais métodos de gestão e eficiência energética que estão sendo empregados nas indústrias. Após o desenvolvimento de estudos preliminares, realizou-se uma auditoria energética em um frigorífico de abate de aves situado na região Sudoeste do Paraná. Nesta auditoria foram estabelecidos os centros de maior consumo, as linhas de base dos principais insumos energéticos e potenciais de conservação de energia dos principais módulos temáticos. Verificou-se que o sistema de refrigeração representa aproximadamente 81% do consumo de energia elétrica da planta e que do total de 11 módulos temáticos existentes, três deles representam aproximadamente 97% do consumo de energia elétrica da planta, sendo motores, sistema de refrigeração e sistema de ar comprimido. Constatou-se também, com uma análise econômica de perdas, que há potenciais de conservação de energia, principalmente em motores. Por fim, identificaram-se as principais barreiras para se implantar um sistema de gestão de energia em uma planta, principalmente no que se refere à elaboração de linhas de base e indicadores de desempenho energético. Tais barreiras demonstram uma falsa expectativa do PNEf para alcançar as atuais metas se não houver maior impacto dos progressos induzidos (por políticas públicas). / This research has an objective to investigate the electrical power efficiency in industries, aiming to identify potential energy saving and possible barriers to deploy an energy management system, having as one of its priorities the main motivations to the release of a National Plan of Electrical Efficiency (NPEE), in which forecast a great power saving for the following years and the norm ABNT NBR ISO 50001-Energy management system. At a first moment, a study was made about the main methods of electrical efficiency management, in which are being introduced in industries. After the development of preliminary studies, an electrical audit was carried out in a poultry slaughter cooler on the southwest region of Paraná. On the audit were established the centers of greater consumption and the baselines of the main energetic imputs and potential ways of electrical energy saving from the main thematic modules.It has been verified that the cooling system represents approximately 81% of electrical energy consumption of the plant and of the total of eleven modules; three of them represent approximately 97% of the power consumption of the entire plant, as engines, cooling system and compressed air system. It has been also found out, with an economic analysis of losses, there are potentials means of power saving, especially when it comes to engines. At last, was identified the main barriers to deploy an energy management system in a plant, mainly as regards the elaboration of baselines and indicators of electrical performance. These barriers have shown a fake expectation of the NPEE to reach the present goals if there's no impact on the progresses prompted (by public politics.)

Este trabalho desenvolve um novo método de controle de eficiência energética no acionamento de motores de indução. Esta técnica utiliza um modelo de perdas e uma estrutura de controle baseada no mínimo consumo de energia elétrica. Em um primeiro momento, são apresentados os estudos com os principais controladores de eficiência energética da última década. Depois, são apresentados os modelos elétricos e mecânicos do motor de indução trifásico, a partir do modelo clássico, com o eixo de referência qd0. O controlador utilizado, é o controle por campo orientado indireto (IFOC - Indirect Field Oriented Control), composto por uma malha externa de controle de velocidade e fluxo, e uma malha interna de controle de correntes, que demonstram um bom desempenho de torque e velocidade. Por se tratar de um controlador IFOC, onde os parâmetros do motor são fundamentais para obter bons resultados, o ensaio do motor de indução é realizado e apresentado. Sabendo-se das principais fontes de perdas do motor, o controlador de eficiência energética pode ser elaborado. O controlador baseado no modelo de perdas (LMC -Loss-Model-Based Control) é descrito, assim como o controlador de busca recursiva (SC - Search Control), ambos muito utilizados na literatura. O LMC proposto é implementado através de curvas padrão de fluxo ótimo baseado na potência absorvida, dependendo da carga no eixo do motor, uma nova curva padrão é utilizada. O controlador de eficiência proposto chamado de (MBC - Model Based Control), utiliza o método LMC com um controlador IFOC, este é simulado via software Matlab e verificado experimentalmente através de uma plataforma de acionamento projetada e montada, conforme o projeto descrito. O controlador de eficiência proposto, é comparado com o acionamento de fluxo constante e com o controlador SC, para diferentes perfis de carga no eixo. Para todos os casos o controlador proposto, apresentou o melhor rendimento da máquina. / This paper develops a new method of controlling the drive energy efficiency of induction motors . This technique uses a model of losses and a control structure based on minimum energy consumption . At first , studies with the main drivers of energy efficiency in the last decade are presented . Then the electrical and mechanical models of three-phase induction motor are presented , from the classic model , with the reference axis qd0 . The controller used is an indirect field-oriented control (IFOC), composed of an outer control loop speed and flow , and an inner current control loop , showing a good performance of torque and speed. Because it is a IFOC controller, where the engine parameters are critical to obtain good results , the testing of induction motor is carried out and presented . Knowing the main sources of losses of the engine, the controller of energy efficiency can be drawn . The loss model based (LMC) controller is described , as well as the controller recursive search (SC), both widely used in the literature . The LMC proposed is implemented through optimum standard curves of flow based on power absorbed. Depending on the load on the motor shaft , a new standard curve is used . The proposed controller called efficiency ( MBC - Model Based Control ) uses the LMC method with a IFOC controller , this is simulated via textit software emph Matlab and verified experimentally through a platform drive designed and assembled , as the project described . The controller proposed efficiency is compared with the drive and the constant flow controller SC to different profiles of the axle. For all cases, the proposed controller showed the best performance of the machine.

Esta pesquisa tem por objetivo efetuar uma investigação acerca da eficiência energética nas indústrias, com foco na identificação dos potenciais de conservação de energia e possíveis barreiras para se implantar um sistema de gestão de energia, tendo como principais motivações o lançamento do Plano Nacional de Eficiência Energética (PNEf), que prevê uma grande economia de energia para os próximos anos, e da norma ABNT NBR ISO 50001- Sistema de gestão de energia. Num primeiro instante, fez-se um estudo dos principais métodos de gestão e eficiência energética que estão sendo empregados nas indústrias. Após o desenvolvimento de estudos preliminares, realizou-se uma auditoria energética em um frigorífico de abate de aves situado na região Sudoeste do Paraná. Nesta auditoria foram estabelecidos os centros de maior consumo, as linhas de base dos principais insumos energéticos e potenciais de conservação de energia dos principais módulos temáticos. Verificou-se que o sistema de refrigeração representa aproximadamente 81% do consumo de energia elétrica da planta e que do total de 11 módulos temáticos existentes, três deles representam aproximadamente 97% do consumo de energia elétrica da planta, sendo motores, sistema de refrigeração e sistema de ar comprimido. Constatou-se também, com uma análise econômica de perdas, que há potenciais de conservação de energia, principalmente em motores. Por fim, identificaram-se as principais barreiras para se implantar um sistema de gestão de energia em uma planta, principalmente no que se refere à elaboração de linhas de base e indicadores de desempenho energético. Tais barreiras demonstram uma falsa expectativa do PNEf para alcançar as atuais metas se não houver maior impacto dos progressos induzidos (por políticas públicas). / This research has an objective to investigate the electrical power efficiency in industries, aiming to identify potential energy saving and possible barriers to deploy an energy management system, having as one of its priorities the main motivations to the release of a National Plan of Electrical Efficiency (NPEE), in which forecast a great power saving for the following years and the norm ABNT NBR ISO 50001-Energy management system. At a first moment, a study was made about the main methods of electrical efficiency management, in which are being introduced in industries. After the development of preliminary studies, an electrical audit was carried out in a poultry slaughter cooler on the southwest region of Paraná. On the audit were established the centers of greater consumption and the baselines of the main energetic imputs and potential ways of electrical energy saving from the main thematic modules.It has been verified that the cooling system represents approximately 81% of electrical energy consumption of the plant and of the total of eleven modules; three of them represent approximately 97% of the power consumption of the entire plant, as engines, cooling system and compressed air system. It has been also found out, with an economic analysis of losses, there are potentials means of power saving, especially when it comes to engines. At last, was identified the main barriers to deploy an energy management system in a plant, mainly as regards the elaboration of baselines and indicators of electrical performance. These barriers have shown a fake expectation of the NPEE to reach the present goals if there's no impact on the progresses prompted (by public politics.)

Orientador: Daniel Joseph Hogan / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Filosofia e Ciencias Humanas / Made available in DSpace on 2018-08-05T19:27:24Z (GMT). No. of bitstreams: 1 Burian_PauloProcopio_D.pdf: 1645822 bytes, checksum: dc51872df58655d0a18c1e5211137371 (MD5) Previous issue date: 2006 / Resumo: Nas últimas décadas, dois movimentos aparentemente antagônicos influenciaram diretamente a absorção da temática socioambiental no nível institucional. Se por um lado ocorreu o processo de globalização com a integração da economia mundial reduzindo a atuação do Estado nacional em setores estratégicos, por outro lado houve uma consolidação dos processos de licenciamento ambiental, conseqüência das pressões exercidas tanto pelos movimentos sociais, quanto pelas agências multilaterais de financiamento. Tomando como ponto de partida a confluência desses dois aspectos distintos que se confrontam e dialogam, o presente estudo visa verificar até que ponto os processos de licenciamento têm desempenhado um papel importante para que as questões socioambientais sejam devidamente incorporadas no setor elétrico brasileiro. Embora esses processos tenham representado um passo importante em direção à sustentabilidade, ainda precisam ser aprimorados de modo a incluir outros aspectos como a consulta pública, que não se encontram plenamente equacionados. A partir da constatação, por meio de estudos de caso, de que os Estudos de Impacto Ambiental - EIAs - têm se mostrado insuficientes na medida em que são elaborados apenas na etapa de projeto, recentemente tem sido introduzida a Avaliação Ambiental Estratégica ¿ AAE, um novo instrumento que tem como objetivo inserir a variável socioambiental na etapa de planejamento para influenciar no processo de tomada de decisão em seu estágio inicial. Embora reconhecidamente a introdução de AAE represente um avanço, não pode ser considerada, de modo algum, como uma solução definitiva para essa questão. Desse modo, sem ter a pretensão de dar respostas definitivas, este trabalho busca levantar diversos aspectos que permeiam a relação entre o setor elétrico e o meio ambiente, demonstrando como as incertezas da era pós-moderna também se refletem nos mecanismos de licenciamento ambiental. Trata-se, portanto, de um processo em permanente construção e fundamentalmente dependente do diálogo para seu aprimoramento / Abstract: In the last decades, two movements apparently opposed have influenced the way of incorporation of environmental debates on the level of the institutions. On the one hand, there is the globalization process which conveys the integration of the capitalist world, weakening the power of the National State in strategic sectors. On the other hand, the license process has been consolidated, due to the pressure of social movements and multi-lateral agencies. Based on this particular context, the present study seeks to verify to which extent the license process has played an important role for the environmental debates to be incorporated in the Brazilian electric sector agenda. Yet the environmental license process is an important step in the direction of sustainability, it needs to be improved, even including issues like public consultation. Case studies about Environmental Impact Assessments - EIAs show that they are insufficient, for they are carried out only during the Project stage. That's why the Strategic Environmental Assessment ¿ SEA has been recently developed. The objective of this new instrument is to incorporate the environmental issues in the Planning stage, then any important decision will be taken in the very beginning. Even though the introduction of SEA has been important, case studies prove that it cannot be considered a final solution to these problems. Yet this study does not bring definitive answers, it intends to identify several pertinent questions regarding the relationship between the electric sector and the environment, suggesting that the uncertainties of the post-modern age are also present in the environmental license instruments. Finally, this process is in permanent construction and it depends fundamentally on constant dialogue to be refined. / Doutorado / Doutor em Ciências Sociais

Wireless Sensor Networks (WSNs) have enticed a strong attention in the research community due to the broad range of applications and services they support. WSNs are composed of intelligent sensor nodes that have the capabilities to monitor different types of environmental phenomena or critical activities. Sensor nodes operate under stringent requirements of scarce power resources, limited storage capacities, limited processing capabilities, and hostile environmental surroundings. However, conserving sensor nodes’ power resources is the top priority requirement in the design of a WSN as it has a direct impact on its lifetime. The IEEE 802.15.4 standard defines a set of specifications for both the PHY layer and the MAC sub-layer that abide by the distinguished requirements of WSNs. The standard’s MAC protocol employs an intelligent backoff algorithm, called the Binary Exponent Backoff (BEB), that minimizes the drainage of power in these networks. In this thesis we present an in-depth study of the IEEE 802.15.4 MAC protocol to highlight both its strong and weak aspects. We show that we have enticing opportunities to improve the performance of this protocol in the context of WSNs. We propose three new backoff algorithms, namely, the Standby-BEB (SB-BEB), the Adaptive Backoff Algorithm (ABA), and the Priority-Based BEB (PB-BEB), to replace the standard BEB. The main contribution of the thesis is that it develops a new design concept that drives the design of efficient backoff algorithms for the IEEE 802.15.4-based WSNs. The concept dictates that controlling the algorithms parameters probabilistically has a direct impact on enhancing the backoff algorithm’s performance. We provide detailed discrete-time Markov-based models (for AB-BEB and ABA) and extensive simulation studies (for the three algorithms) to prove the superiority of our new algorithms over the standard BEB.

M.Phil. (Energy Studies) / In recent years, the costs of electricity in South Africa have increased enormously, thus, most institutions of higher education are seeking ways to manage their utility costs by reducing consumption rates. Hampering their initiatives, however, is the fact that South Africa in general, and buildings in particular, lag the world in knowledge and implementation of demand side management strategies. This case study outlines the efforts of a large metropolitan university in Gauteng to examine the implementation of energy efficiency within the context of the green or sustainable campus movement. The study comprises three core parts: analysis of electricity consumption data; identification of institutional barriers inhibiting implementation of energy efficiency projects, and, lastly establishing key role players responsible for effective implementation. The study found that seasonality and the campus academic calendar both have profound effects on energy consumption. High demand coincides with winter and a distinct correlation was found between peak consumption and core working hours. Consumption peaked at an average of 2 500 kWh during active ‘in-session’ periods. Less active, ‘out-of-session periods’ recorded an average peak of 2 250 kWh. The lowest average peak consumption of 2 100 kWh occurred during ‘recess’ periods. Similar patterns were evident for the maximum demand. It was evident that the university had a high base load (between 1 300 kWh and 1 650 kWh). This high base load could be attributed mainly to the heating and cooling system. To stimulate decision making towards improved options, an energy savings financial model was developed to provide a tool for calculating the return on investment period for energy efficiency projects. Interviews conducted with key role players (in the university’s operations, academic and management divisions) and a staff questionnaire were used to establish the main barriers to energy efficiency implementation: a) the absence of an energy policy; b) a general low level of awareness of institutional energy efficiency activities and (c) the shortage of dedicated, skilled staff to implement energy efficiency projects. The managerial, operational, and financial divisions are arguably the key role players in energy efficiency projects. Lastly, leadership commitment from the highest levels of the university is required. The novel contribution of this thesis is through combining technological and behavioural approaches to energy efficiency at a tertiary institution through a mixed method study design. Key recommendations are presented to stimulate energy efficiency implementation.

<p>We examine energy harvesting sensor networks, more specifically, a sensor network using the Geographic Routing with Environmental Energy Supply (GREES) algorithm. We start with a discussion of other sources of energy conservation both in energy harvesting and non-energy harvesting sensor networks. Ideas presented in these works are combined where possible with the GREES algorithm. A sensor network was actually built to test and (if possible) improve the algorithm. There were problems along the way, but they were overcome to produce a functioning energy harvesting sensor network that used solar cells as the energy harvesting unit. Tests were run on the network by giving a consistent light and battery supply, and then changing parameters of the algorithm to see their effect on the lifetime of the network, indicating the network's sensitivity to individual parameters. These results are presented, along with their interpretation, as well as an error analysis detailing the behaviour of the algorithm. We discuss how sensitive the network is to each parameter, indicating which parameters are more important to calibrate or measure correctly.</p> / Master of Applied Science (MASc)

Thesis (DTech (Electrical Engineering))--Cape Peninsula University of Technology, 2011. / Electrical energy is an important resource for human and economic development. On the demand side, electrical energy management is needed because of the tendency of manufacturing industries to consume large amount of energy and as a result lead them to spend more money in paying bills for the consumed electrical energy. In addition, the amount of electrical energy generated in Sub-Saharan Africa is incomparable with demand requirements. The predominant sources of electrical energy generation are fossil fuels and hydro. Generation of electricity by fossil fuel needs high capital investments and high running costs. Concurrently, the process of burning fossil fuels has an adverse effect on the environment. In order to minimize these effects, electrical energy management in manufacturing industries has to be instituted and implemented. In this research, a study has been undertaken to develop methods and strategies to be used as tools for electrical energy management in manufacturing industries and it is aimed at reducing electrical energy consumption. The research method adopted/used includes: survey of several cement industries in order to obtain current and historical electrical energy consumption, production data and to be acquainted with the methods used for energy management, measurement of electrical parameters, investigation of the use of electrical power in cement industries, analysis of power factor and power factor correction methods, analysis of energy efficiency potentials and technology used for energy saving. From the data gathered, the following were developed: strategies for the overall electrical energy management for cement plant, strategies for energy efficiency potential and technology used for energy saving, an algorithm for assessing the potential options of DSM, an algorithm for performing industrial load scheduling, an industrial energy consumption model using regression analysis technique and a Static Synchronous Compensator (STATCOM) for industrial power factor improvement. Also, a numerical analysis and computer simulation using MATLAB/Simulink were implemented. Moreover PSIM and Excel software were used in the developed energy consumption model and for the power factor improvement method. Numerical analysis and computer simulation showed that the developed STATCOM has the capability of improving and varying of power factor in accordance with the variation of plant loads, it improves power factor and reduces harmonics of the respective industries. Using the developed algorithm for assessing potentials of DSM options, it was found that, most of the energy management techniques used in manufacturing industries worldwide are not implemented in the visited industries. The developed methods and strategies can be used in improving power factor, prediction of electrical energy consumption and also for development of energy consumption benchmarking in cement industries. They can be also extended and used in mining and other manufacturing industries such as paper, textiles and this can create condition for sustainable energy management program in manufacturing industries.

Thesis (Dtech (Electrical Engineering))--Cape Peninsula University of Technology, 2011. / Electrical energy is an important resource for human and economic development. On the demand side, electrical energy management is needed because of the tendency of manufacturing industries to consume large amount of energy and as a result lead them to spend more money in paying bills for the consumed electrical energy. In addition, the amount of electrical energy generated in Sub-Saharan Africa is incomparable with demand requirements. The predominant sources of electrical energy generation are fossil fuels and hydro. Generation of electricity by fossil fuel needs high capital investments and high running costs. Concurrently, the process of burning fossil fuels has an adverse effect on the environment. In order to minimize these effects, electrical energy management in manufacturing industries has to be instituted and implemented.