The objective of the research is to develop a cost-effective, dynamic grid controller called the controllable network transformer (CNT) that can be implemented by augmenting existing load tap changing (LTC) transformers with an AC-AC converter. The concept is based on using a fractionally rated direct AC-AC converter to control the power through an existing passive LTC. By using a modulation strategy based on virtual quadrature sources (VQS), it is possible to control both the magnitude and the phase angle of the output voltage of the CNT without having any inter-phase connections. The CNT architecture has many advantages over existing power flow controllers, like absence of low frequency storage, fractional converter rating, retro-fitting existing assets and independent per-phase operation making it potentially attractive for utility applications. The independent control of the magnitude and the phase angle of the output voltage allow independent real and reactive power flow control through the CNT-controlled line. In a meshed network with asymmetric network stresses this functionality can be used to redirect power from critically loaded assets to other relatively under-utilized parallel paths. The power flow controllability of CNT can thus be used to lower the overall cost of generation of power. The solid state switches in the CNT with fast response capability enable incorporation of various additional critical functionalities like grid fault ride through, bypassing internal faults and dynamic damping. This bouquet of features makes the CNT useful under both steady state and transient conditions without compromising the grid reliability.

The Energy Independence and Security Act of 2007 established that the current electric grid was inadequate to serve the United States needs. Congress mandated that the U.S. transition to a more intelligent grid for the future. The Department of Energy was tasked with making this goal a reality. Six years later in 2013, only marginal progress has been made. Outside of smart meter rollouts and pilots programs funded through the American Recovery and Reinvestment Act of 2009 (ARRA), many issues still need to be addressed in order to realize the U.S. Smart Grid vision. Most of the barriers to progress are not technological; the research and business community are rising to the occasion and meeting the challenge through innovation. However, policy issues present a large barrier to overcome. With issues ranging from vague Smart Grids goals issued by the Department of Energy to a general lack of consumer knowledge about the Smart Grid. This paper seeks to identify the gaps in the current electric grid and policy schema are inadequate and suggest recommendations to encourage and expedite the growth of the U.S. Smart Grid.

Orientador: Aílton Akira Shinoda / Co-orientador: Ruy de Oliveira / Banca: Christiane Marie Schweitzer / Banca: Élvio João Leonardo / Resumo: Nas últimas décadas, os desafios no setor de energia elétrica têm aumentado significativamente, quer seja por questões referentes à forma como a energia é gerada e distribuída, ou pela postura do consumidor perante a rede elétrica. Diante da necessidade de uma reestruturação no negócio de energia elétrica, países investem em um conceito conhecido como Smart Grid, que tem como alvo a otimização e automação da rede de energia elétrica, utilizando tecnologias de informação e comunicação avançadas. Entre os principais objetivos propostos pela implementação das Smart Grids estão: aumento na confiabilidade da rede; redução de falhas no fornecimento de energia; redução de tempo e custo com manutenção na rede; registros mais precisos do consumo de energia; inserção de fontes renováveis de energia na rede, a fim de proporcionar um ambiente mais limpo. Investimentos em tecnologias de comunicação, componente fundamental para o bom desempenho das Smart Grids, merecem atenção especial. Diminuir o tempo de recuperação a falhas, inserir fontes de energias alternativas, entre outras funcionalidades, requerem uma rede eficiente e rápida. Os domínios de uma Smart Grid, possuem demandas de comunicação diversificadas, o que exige o emprego de diferentes tecnologias de comunicação, tornando sua implementação complexa. Dentre os protocolos de comunicação existentes, o Distributed Network Protocol 3.0 (DNP3) é um protocolo de comunicação baseado nas especificações do IEC (International Eletrotechnical Commission) e adaptado para ser utilizado em aplicações altamente seguras com taxa de transmissão de dados moderada. Vários trabalhos apontam para possíveis utilizações do protocolo DNP3 em conjunto com outros padrões de comunicação (IEEE 802.3, IEEE 802.11, IEEE 802.15.4). O IEEE 802.15.4 é um padrão de baixo consumo e seu uso tem sido difundido como solução adequada para redes de sensores sem fio em... / Abstract: Over the last decades, the challenges in the electricity sector have significantly increased, either by the issues regarding the way energy is generated and distributed by the consumer's attitude towards the electrical grid. In order to restructure the business model in the electricity sector, countries around the world have decided to invest in a concept known as Smart Grid. This system includes technologies such as digital, information and communication Technology (ICT). This concept aims to optimize and automate the electricity sector. The major changes proposed by the implementation of the Smart Grid are: higher network reliability, less failures in the power supply, lower time and costs of maintenance in the network, more accurate records of energy use by the consumer; and insertion of new energy sources in the network, contributing to reducing carbon dioxide emissions. Thus, investments in communication technologies is considered a key component for the performance of Smart Grids, as this technology demands diversified communication protocols that have to be fast and might involve a complex communication network. Among the existing communication protocols, the Distributed Network Protocol 3.0 (DNP3) is a protocol based on the specifications of the IEC (International Electrotechnical Commission) and adapted for use on highly secure applications with moderate data transmission rates. Several studies have pointed to possible use of the DNP3 protocol in conjunction with other communication standards such as IEEE 802.3, IEEE 802.11 and IEEE 802.15.4. The IEEE 802.15.4 is a standard for low power consumption and it has been disseminated as an appropriate solution for wireless sensor networks in several areas, such as industrial, commercial, residential and academic. The implementation of a heterogeneous communication network - to study and evaluate the behavior of a particular technology - is a highly costly process. However, computer ... / Mestre

Made available in DSpace on 2015-10-06T13:03:21Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-05-29. Added 1 bitstream(s) on 2015-10-06T13:18:36Z : No. of bitstreams: 1 000849391.pdf: 1107397 bytes, checksum: bd9d3a3de608590a9fa280ebff84518f (MD5) / Nas últimas décadas, os desafios no setor de energia elétrica têm aumentado significativamente, quer seja por questões referentes à forma como a energia é gerada e distribuída, ou pela postura do consumidor perante a rede elétrica. Diante da necessidade de uma reestruturação no negócio de energia elétrica, países investem em um conceito conhecido como Smart Grid, que tem como alvo a otimização e automação da rede de energia elétrica, utilizando tecnologias de informação e comunicação avançadas. Entre os principais objetivos propostos pela implementação das Smart Grids estão: aumento na confiabilidade da rede; redução de falhas no fornecimento de energia; redução de tempo e custo com manutenção na rede; registros mais precisos do consumo de energia; inserção de fontes renováveis de energia na rede, a fim de proporcionar um ambiente mais limpo. Investimentos em tecnologias de comunicação, componente fundamental para o bom desempenho das Smart Grids, merecem atenção especial. Diminuir o tempo de recuperação a falhas, inserir fontes de energias alternativas, entre outras funcionalidades, requerem uma rede eficiente e rápida. Os domínios de uma Smart Grid, possuem demandas de comunicação diversificadas, o que exige o emprego de diferentes tecnologias de comunicação, tornando sua implementação complexa. Dentre os protocolos de comunicação existentes, o Distributed Network Protocol 3.0 (DNP3) é um protocolo de comunicação baseado nas especificações do IEC (International Eletrotechnical Commission) e adaptado para ser utilizado em aplicações altamente seguras com taxa de transmissão de dados moderada. Vários trabalhos apontam para possíveis utilizações do protocolo DNP3 em conjunto com outros padrões de comunicação (IEEE 802.3, IEEE 802.11, IEEE 802.15.4). O IEEE 802.15.4 é um padrão de baixo consumo e seu uso tem sido difundido como solução adequada para redes de sensores sem fio em... / Over the last decades, the challenges in the electricity sector have significantly increased, either by the issues regarding the way energy is generated and distributed by the consumer's attitude towards the electrical grid. In order to restructure the business model in the electricity sector, countries around the world have decided to invest in a concept known as Smart Grid. This system includes technologies such as digital, information and communication Technology (ICT). This concept aims to optimize and automate the electricity sector. The major changes proposed by the implementation of the Smart Grid are: higher network reliability, less failures in the power supply, lower time and costs of maintenance in the network, more accurate records of energy use by the consumer; and insertion of new energy sources in the network, contributing to reducing carbon dioxide emissions. Thus, investments in communication technologies is considered a key component for the performance of Smart Grids, as this technology demands diversified communication protocols that have to be fast and might involve a complex communication network. Among the existing communication protocols, the Distributed Network Protocol 3.0 (DNP3) is a protocol based on the specifications of the IEC (International Electrotechnical Commission) and adapted for use on highly secure applications with moderate data transmission rates. Several studies have pointed to possible use of the DNP3 protocol in conjunction with other communication standards such as IEEE 802.3, IEEE 802.11 and IEEE 802.15.4. The IEEE 802.15.4 is a standard for low power consumption and it has been disseminated as an appropriate solution for wireless sensor networks in several areas, such as industrial, commercial, residential and academic. The implementation of a heterogeneous communication network - to study and evaluate the behavior of a particular technology - is a highly costly process. However, computer ...

Made available in DSpace on 2015-07-13T12:10:34Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-02-19. Added 1 bitstream(s) on 2015-07-13T12:24:06Z : No. of bitstreams: 1 000835910.pdf: 3667690 bytes, checksum: 92c1f352db880f910375264940dd3859 (MD5) / Este trabalho tem como objetivo o desenvolvimento de um sistema de gerenciamento de energia avançado para operar a smart grid, que é constituída pela interseção do sistema elétrico com as tecnologias de comunicação e informação. Atualmente existem diversos estudos relacionados à smart grid e isso pode gerar dúvidas sobre o conceito de projeto da smart grid. Para evitar eventuais dúvidas, na primeira parte deste trabalho, é apresentada uma introdução contendo as novas tecnologias usadas na smart grid bem como uma descrição da padronização desse novo conceito de projeto. A partir do padrão de projeto, foi possível destacar e desenvolver cada componente do sistema de gerenciamento de energia avançado. Os componentes lógicos, que exigem recursos da tecnologia de informação, foram elaborados e implantados em um sistema computacional, já os equipamentos físicos de comunicação e do sistema elétrico foram meticulosamente emulados. A simulação dos equipamentos elétricos foi fundamentada no algoritmo de fluxo de potência probabilístico que permitiu tanto a flutuação de carga quanto a atuação do mercado de energia. As condições de falta também foram consideradas no simulador de equipamentos elétricos fornecendo dados de medições elétricas para outros componentes do sistema de gerenciamento de energia. Um desses componentes é o algoritmo de estimação de estados que produz o estado da rede de distribuição usando os dados de medição. Estes estados produzidos pelo estimador de estados são entradas das funções avançadas do sistema de gerenciamento de energia como as ferramentas de coloração dinâmica e localização de perdas não técnicas. Todas as metodologias propostas neste trabalho foram avaliadas e os resultados numéricos demonstram sua eficiência / This work aims the development of an advanced energy management system to operate the smart grid that comprises the intersection of electrical power system with communication and information technologies. There are, currently, many studies related to the smart grid, which can produce doubts about the smart grid design concept. These doubts are clarified in the first part of this work where novel technologies of smart grid are presented besides the description of the standardization of smart grid design concepts. The use of the smart grid design standard allows identifying and developing all components of the advanced energy management system. The logical components, which require resources of information technology, were developed and implemented in a computational environment, while the physical devices of communication and power systems were meticulously emulated. The electrical devices emulation is based on the probabilistic power flow algorithm that permits both the load fluctuation and the energy market influence. The electrical devices simulator also supports contingency conditions as well as provides electric measurement data to other components of the energy management system. One of these components is the state estimation algorithm that produces the distribution network state using the measurement data. Network states produced by the state estimator are employed in advanced functions of the energy management system like the dynamic coloring, location of non-technical losses and self-healing applications. All proposed methodologies, in this work, were assessed and numerical results demonstrated their efficiencies

Thesis submitted in fulfilment of the requirements for the degree Doctor of Technology: Electrical Engineering in the Faculty of Engineering at the Cape Peninsula University of Technology 2014 / Distributed generation (DG) has been reincarnated after its demise by centralised generation. While economy of scale and efficiency are the advantages of the latter, deregulation of the electricity market, environmental concerns and the need to arrest dwindling reserve margins have necessitated the rebirth of the former. Indeed, a full circle has therefore evolved with generation being ‘embedded’ in distribution systems and ‘dispersed’ around the system rather than being located and dispatched centrally or globally. This development is in tandem with the history of industrial revolutions that started from energy and moved through services and communication and back to energy. South Africa is not immune to the global energy, especially tertiary energy, challenge phenomenon. At the peak of the 2007-2008 energy crisis, her generation net reserve margin fell below 10% – well below conventional industry benchmark of at least 15%. Also South Africa is Africa’s largest emitter of CO2 contributing over 40% of Africa’s total CO2 emissions. Therefore, DG’s relevance to South Africa is quite obvious. However, DG integration into distribution networks leads to a number of challenges. For instance, with significant penetration of DG power flow reversal may be experienced and the distribution network will no longer be a passive circuit. This underscores the crucial role of ICT in active distribution network occasioned by DG and especially the emergent of “prosumerism” (a hitherto consumer also becoming a producer). Therefore, a smart grid and similar phrases have all been used to describe a “digitised” and intelligent version of the present-day power grid. There are immense benefits derivable from modelling and simulation. Consequently, a typical radial distribution network model has been developed to evaluate the considerable impacts of DG integration. The modelling and simulation of the network are accomplished using the DIgSILENT PowerFactory simulation package. Impacts of DG on voltage profile, fault level, voltage stability and protection coordination have been investigated and their possible mitigation measures proferred. The results reveal that for a particular DG type its impacts depend mainly on its capacity and point of connection relative to a given load type. Smart grid technology addresses some of these impacts through its inherent capability which includes peer-to-peer relay communication for protective devices on the distribution feeder as well as communication to the DG facility.

Thesis (MTech (Electrical, Electronic and Computer Engineering))--Cape Peninsula University of Technology, 2015. / The growing interest in the use of solar energy to mitigate climate change, reduction in the cost of PV system and other favourable factors have increased the penetration of the PV(Photovoltaic) systems in the market and increase in the worldwide energy supply. The main component in a DG is a smart inverter connected in a grid-tied mode which serves as a direct interface between the grid and the RES (Renewable Energy System). This research work presents a three phase grid-tied inverter with active and reactive power control capabilities for renewable energy sources (RES) and distributed generators (DG). The type of the inverter to be designed is a Voltage Source Inverter (VSI). The VSI is capable of supplying energy to the utility grid with a well regulated DC link at its input. The solution this project proposes is an implementation of the designed filter to effectively reduce the harmonics injected into the grid to an acceptable value according to standards and also an approach to control the real and reactive power output of the inverters to help solve the problems of instability and power quality of the distribution system. The design, modelling and simulation of the smart inverter system is performed in MATLAB/SIMULINK software environment. A 10 kW three-phase voltage source inverter system connected to the utility grid was considered for this research. Series of simulations for the grid-connected inverter (GCI) model was carried out using different step changes in active and reactive power references which was used to obtain the tracking response of the set power references. The effectiveness of the control system which was designed to track the set references and supply improved power quality with reduced current ripples has been verified from the simulation results obtained.

Orientador: José Roberto Sanches Mantovani / Banca: Antonio Padilha Feltrin / Banca: Rubén Augusto Romero Lázaro / Banca: Rogério Andrade Flauzino / Banca: Carlos Alberto Castro Junior / Resumo: Este trabalho tem como objetivo o desenvolvimento de um sistema de gerenciamento de energia avançado para operar a smart grid, que é constituída pela interseção do sistema elétrico com as tecnologias de comunicação e informação. Atualmente existem diversos estudos relacionados à smart grid e isso pode gerar dúvidas sobre o conceito de projeto da smart grid. Para evitar eventuais dúvidas, na primeira parte deste trabalho, é apresentada uma introdução contendo as novas tecnologias usadas na smart grid bem como uma descrição da padronização desse novo conceito de projeto. A partir do padrão de projeto, foi possível destacar e desenvolver cada componente do sistema de gerenciamento de energia avançado. Os componentes lógicos, que exigem recursos da tecnologia de informação, foram elaborados e implantados em um sistema computacional, já os equipamentos físicos de comunicação e do sistema elétrico foram meticulosamente emulados. A simulação dos equipamentos elétricos foi fundamentada no algoritmo de fluxo de potência probabilístico que permitiu tanto a flutuação de carga quanto a atuação do mercado de energia. As condições de falta também foram consideradas no simulador de equipamentos elétricos fornecendo dados de medições elétricas para outros componentes do sistema de gerenciamento de energia. Um desses componentes é o algoritmo de estimação de estados que produz o estado da rede de distribuição usando os dados de medição. Estes estados produzidos pelo estimador de estados são entradas das funções avançadas do sistema de gerenciamento de energia como as ferramentas de coloração dinâmica e localização de perdas não técnicas. Todas as metodologias propostas neste trabalho foram avaliadas e os resultados numéricos demonstram sua eficiência / Abstract: This work aims the development of an advanced energy management system to operate the smart grid that comprises the intersection of electrical power system with communication and information technologies. There are, currently, many studies related to the smart grid, which can produce doubts about the smart grid design concept. These doubts are clarified in the first part of this work where novel technologies of smart grid are presented besides the description of the standardization of smart grid design concepts. The use of the smart grid design standard allows identifying and developing all components of the advanced energy management system. The logical components, which require resources of information technology, were developed and implemented in a computational environment, while the physical devices of communication and power systems were meticulously emulated. The electrical devices emulation is based on the probabilistic power flow algorithm that permits both the load fluctuation and the energy market influence. The electrical devices simulator also supports contingency conditions as well as provides electric measurement data to other components of the energy management system. One of these components is the state estimation algorithm that produces the distribution network state using the measurement data. Network states produced by the state estimator are employed in advanced functions of the energy management system like the dynamic coloring, location of non-technical losses and self-healing applications. All proposed methodologies, in this work, were assessed and numerical results demonstrated their efficiencies / Doutor

Orientador: Paulo José Amaral Serni / Co-Orientador: Eduardo Paciência Godoy / Banca: Claudionor Francisco do Nascimento / Banca: André Luiz Andreoli / Resumo: A crescente demanda de energia elétrica devido ao crescimento populacional nos últimos anos, resultou em uma necessária expansão da matriz energética por meio de fontes alternativas, incluindo os consumidores também geradores de energia de pequeno porte, em baixa ou média tensão. Sendo assim, estudos vêm sendo realizados para inserir a automação no controle desses sistemas, porém ainda não foi estabelecido o que será controlado e como obter os dados de forma eficaz. No cenário de microrredes, um dos grandes desafios é a automação do processo de comunicação da rede entre diferentes dispositivos, tais como controladores de geradores, medidores inteligentes, etc., a fim de facilitar a troca de informações e melhorar o desempenho da rede. Portanto, este trabalho apresenta um estudo de simulação de microrredes (MR) com geração distribuída (GD) controlada remotamente, através de uma comunicação sem fio. A metodologia é apresentada através da simulação integrada de redes inteligentes, na qual o sistema elétrico foi implementado através do software PLECS - blockset, enquanto a rede sem fio foi projetada através do software TrueTime - toolbox, ambos simulados no Matlab®/Simulink®. Nesta aplicação de MR, é avaliado o uso de uma rede sem fio ZigBee e Wi-Fi, para controlar a geração da potência ativa da GD sob diferentes parâmetros de rede, tais como a probabilidade de perda e distância entre os dispositivos. Os resultados mostram que a simulação apresenta uma proposta viável para uma an... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The increasing use of electricity due to the population growth in recent years has resulted in a necessary expansion of the energy matrix through alternative sources, including prosumers in low or medium voltage. Therefore, studies have been carried out to introduce automation in the control of these systems, but is has not yet been established what will be controllled and how to get the data effectively. In the microgrids scenario, one of the great challenges is the automation of the process of communication of the network between different devices, such as generators controllers, smart meters, etc., in order to facilitate the information exchange and improve network performance. Therefore, this work presents a study of a Microgrid (MG) with a Distributed Generator (DG) controlled remotely through a wirelless communication. The methodology is presented through the integrated of smart grid simulations, where the electrical system was implemented through PLECS - blockset software, while the wireless network was developed using TrueTime - toolbox software, both simulated in Matlab/Simulink. In this application, the use of a ZigBee and Wi-Fi wireless network is evaluated to control the generation of the active power of DG under different network paramenters, such as the loss probility and distance between devices. The simulation results show that the effectiveness of networked solution for developing MG The results show that the simulation presents a feasible proposal for a communication networks analysis, with control of the DG and modeling and development of electric network in the smart MG / Mestre

Orientador: Rubens Alves Dias / Coorientador: José Antonio Perrella Balestieri / Banca: Marco Aurélio Alvarenga Monteiro / Banca: Carlos Alberto Moreira dos Santos / Resumo:Os processos crescentes de industrialização e urbanização das cidades levaram a inúmeros problemas ambientais. As preocupações com as mudanças climáticas são crescentes, a segurança do fornecimento de energia é imprescindível, a competitividade deste mercado, além da necessidade de integrar ações crescentes de energia renovável ao sistema, como também recursos energéticos dispersos. A rede inteligente ou smart grid representa uma das maiores revoluções em infraestrutura no setor de energia elétrica, surgindo como resposta a todos estes anseios. São tecnologias de informação, telecomunicações e técnicas em eletrônica aplicadas na automação e melhoria do setor, modificando a maneira que a eletricidade é gerada, entregue e utilizada. Muitos países estão nesta corrida para a implantação das redes inteligentes, no Brasil, projetos pilotos de redes inteligentes estão sendo implementados por todo o país. São características de um sistema de rede inteligente: condições de auto recuperação, alta qualidade de energia, operação mais eficiente, acomodação de todo tipo de geração e armazenamento de energia e motivar os consumidores a serem ativos. O sistema de eletricidade, dentro do conceito de redes inteligentes, permite o fluxo bidirecional de comunicação e de energia elétrica entre fornecedores e consumidores, transforma o usuário final em consumidor ativo, em outras palavras o papel do consumidor é o motor fundamental, portanto, entender o seu comportamento e reações, assim como motivá-lo e capacitá-lo para este papel é uma preocupação de governos e fornecedores de energia à procura de métodos inovadores para mudar a forma que a eletricidade é percebida. Neste trabalho é apresentada uma visão geral de redes inteligentes e a educação necessária ao consumidor de energia ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The increasing industrialization and urbanization process of cities led to numerous environmental problems. The concerns over climate change are growing, the security of energy supply is crucial, the competitiveness of this market, besides the need to integrate increasing shares of renewable energy to the system, as well as dispersed energy resources. The smart grid is one of the biggest revolutions in the electricity infrastructure sector, emerging as answer to all these anxieties. They are information technology, telecommunication and electronic techniques applied in the automation and improvement of the sector by modifying the way electricity is generated, delivered and used. There are many countries in this race for the implementation of smart grids, in Brazil there are smart grid pilot projects being implemented across the country. As characteristics of a smart grid system we have: conditions of auto recovery, high quality energy, more efficient operation, accommodation of all types of generation and storage energy and motivate consumers to be active. The electricity system, considering the smart grid concepts, permits two-way flow of communication and energy between suppliers and consumers, it transforms the final user in an active consumer, in other words, the consumer's role is the key driver, therefore understanding their behavior and reactions, as well as motivate them and enable then for this role is a governmental and energy suppliers concern looking for innovative methods to change the way electricity is perceived. This work presents an overview of smart grids and the necessary education to electrical energy consumers to assume their role within this new reality. The education learning theory that was based this work is the Vygotsky social interactionism which is based on cognitive development construction, from ... (Complete abstract click electronic access below) / Mestre