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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.
181

MULTISTEP FRAMEWORK FOR SHORT-TERM LOAD FORECASTING USING MACHINE LEARNING ALGORITHM

Silwal, Hari 01 May 2018 (has links)
Traditional forecasting approaches forecast the total system load directly without considering the individual consumer's load. With the introduction of the smart grid, lots of renewable energy resources such as wind and solar are added to the system from consumer side fluctuates the system load and makes forecasting more complex. Thus, it is necessary to forecast individual consumers load. Here, a framework is presented in which individual customer loads is forecasted rather than the system load. At first, a hierarchical cluster analysis is performed to classify daily load patterns into different groups for all the individuals. Then an association analysis is performed to determine critical influential factors that affect the load curve for given day. The next step is the application of a decision tree to establish classification rules between the different groups of the load curve and the critical influential factors. Then, appropriate forecasting models are chosen for different load patterns and the individual load is forecasted. Finally, the forecasted total system load is obtained through an aggregation of an individual load forecasting results. The relative error of forecasting the system load using this framework is compared with the relative errors using SVM regression and this framework had better accuracy. This framework is also used for forecasting the power output of the renewable generation. Also, the results of the day ahead forecast of system load and renewable generation is used for economic power scheduling for the microgrid and peak shaving for the utilities.
182

Optimization and Control for Microgrid and Power Electronic Converters

Rasouli Disfani, Vahid 16 September 2015 (has links)
The proposed dissertation research investigates Optimization and Control for Microgrid and Power Electronic Converters. The research has two major parts: i- Microgrid Operation and Control, ii- Power Electronic Converter Control and Optimization. In the first part, three focuses are investigated. First, a completely distributed algorithm is developed for dc optimal power flow problem for power distribution systems as one of the necessary functions considered in unit-commitment problem in day-ahead markets. This method is derived based upon the partial primal-dual representation of the economic dispatch problem, which is finally translated to DC-OPF problem. Second, the optimal interaction between the utility and communities will be studied, due to its improtance in real-time markets. The objective of this section will be to develop an iterative agent-based algorithm for optimal utility-community control. The algorithm will consider the AC power system constraints to maintain power system stability. In this algorithm, a simplified model of microgrid is considered. In the third focus, a comprehensive model of microgrid is taken into account. The optimal operation of the microgrid considering energy storage systems and renewable energy resources is investigated. The interaction of such microgrids with the main grid to define the optimal operation of the entire embedded system is studied through two iterative methods. In the microgrid's internal problem, a moving-horizon algorithm is considered to define the optimal dispatch of all distributed energy resources while considering the time-correlated constraints of energy storage systems. A thorough analysis of the effects of the size of storage systems on energy and reserve market parameters are also performed. In the second part, the focus of research is to develop optimal control strategies for Power Electronic Converters. A Model Predictive Control (MPC) switching method is proposed for Modular Multilevel Converters (MMC). The optimal solution of MPC problem is then represented as an optimization problem. Due to lack of efficient algorithms to seek the optimal solution, a fast algorithm will be proposed in this research. The method proposed reduces the number of possible solutions and computation efforts dramatically.
183

Proposta de um novo modelo matemático para gerenciamento ótimo de energia elétrica pelo lado do consumidor / Propuesta de un nuevo modelo matemático para la gestión óptima de energía eléctrica por el lado del consumidor

Sanchez, Luis Carlos [UNESP] 14 July 2017 (has links)
Submitted by LUÍS CARLOS SANCHEZ null (luissanchez-123@hotmail.com) on 2017-09-15T15:17:01Z No. of bitstreams: 1 DISSERTAÇÃOLUISCARLOSSANCHEZ.pdf: 2890277 bytes, checksum: cfea2bf60d40685c6c36c43b6e60fd5b (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-09-15T15:21:08Z (GMT) No. of bitstreams: 1 sanchez_lc_me_ilha.pdf: 2890277 bytes, checksum: cfea2bf60d40685c6c36c43b6e60fd5b (MD5) / Made available in DSpace on 2017-09-15T15:21:08Z (GMT). No. of bitstreams: 1 sanchez_lc_me_ilha.pdf: 2890277 bytes, checksum: cfea2bf60d40685c6c36c43b6e60fd5b (MD5) Previous issue date: 2017-07-14 / No contexto de gestão e conservação de energia elétrica, ferramentas de apoio ao consumidor para gerenciar sua demanda são fundamentais para a otimização do uso dos recursos energéticos de modo a minimizar os custos com energia elétrica e ao mesmo tempo garantir o conforto do consumidor, considerando que este consumidor esteja inserido em um ambiente de Gerenciamento pelo Lado da Demanda (GLD). Assim, este trabalho propõe um novo modelo matemático de programação linear inteira mista (PLIM) para resolver o problema de gerenciamento ótimo de energia elétrica pelo lado do consumidor. O modelo matemático é baseado na minimização do custo da energia elétrica e maximização do conforto do consumidor, levando em conta a minimização da diferença entre o consumo habitual e o consumo ótimo, e a minimização da potência absorvida da rede. O modelo é implementado em linguagem de programação AMPL e resolvido utilizando o solver CPLEX. A metodologia é aplicada para gerenciar um conjunto de cargas típicas residenciais e os resultados mostram sua eficiência e potencial para gerenciar de forma ótima a demanda do consumidor, considerando a tarifa de energia elétrica com preço variável, geração distribuída, armazenamento de energia em banco de baterias e veículos elétricos. / In the context of the management and conservation of electric energy, consumer support tools to manage their demand are fundamental for optimizing the use of energy resources in order to minimize energy costs and at the same time guarantee consumer comfort, considering that the consumer is inserted in a Demand Response (DR) environment. Thus, this work proposes a new mathematical model of mixed integer linear programming (MILP) to solve the problem of optimal management of electrical energy by the consumer side. The mathematical model is based on minimizing the cost of electrical energy, maximizing consumer comfort, taking into account the minimization of the difference between habitual consumption and optimal consumption, and minimizing the power consumed by the network. The model is implemented in AMPL programming language and solved using the CPLEX solver. The methodology is applied to manage a set of typical residential loads and the results show its efficiency and potential to optimally manage the consumer demand, considering the price of electricity with variable price, distributed generation, storage of energy in bank of batteries and electric vehicles.
184

Metodologia para análise e interpretação de alarmes em tempo real de sistemas de distribuição de energia elétrica /

Leão, Fábio Bertequini. January 2011 (has links)
Orientador: Jose Roberto Sanches Mantovani / Banca: Rubén Augusto Romero Lázaro / Banca: Carlos Roberto Minussi / Banca: Oriane Magela Neto / Banca: Julio Cesar Stacchini de Souza / Resumo: Neste trabalho é proposta uma metodologia para a análise e interpretação de alarmes em tempo real em sistemas de distribuição de energia elétrica, considerando o diagnóstico em nível de subestações e redes. A metodologia busca superar as dificuldades e desvantagens dos métodos já propostos na literatura especializada para resolver o diagnóstico de faltas em sistemas de potência. O método proposto emprega um modelo matemático original bem como um novo algoritmo genético para efetuar o diagnóstico dos alarmes de maneira eficiente e rápida. O modelo matemático é dividido em duas partes fundamentais: (1) modelo de operação do sistema de proteção; e (2) modelo de Programação Binária Irrestrita (PBI). A parte (1) é composta por um conjunto de equações de estados esperados das funções de proteção dos relés do sistema, modeladas com base na lógica de operação de funções de proteção tais como sobrecorrente, diferencial e distância, bem como na filosofia de proteção de sistemas de potência. A parte (2) é estabelecida através de uma função objetivo formulada com base na teoria de cobertura parcimoniosa (parcimonious set covering theory), e busca a associação ou "match" entre os relatórios de alarmes informados pelo sistema SCADA (Supervisory Control and Data Acquisition) e os estados esperados das funções de proteção formuladas na parte (1) do modelo. O novo algoritmo genético proposto é empregado para minimizar o modelo de PBI e possui como característica a utilização de dois parâmetros de controle. O algoritmo possui taxas de recombinação e mutação automática e dinamicamente calibradas, baseadas na saturação da população corrente, possuindo uma imediata resposta à possível convergência prematura para ótimos locais. A metodologia desenvolvida para o diagnóstico... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This work proposes a methodology for the analysis and interpretation of real-time alarms in electric power distribution systems in the substation level and network level. The methodology seeks to overcome the difficulties and disadvantages of the methods already proposed in the literature to solve the fault diagnosis in power systems. The proposed method employs a novel mathematical model and a genetic algorithm to carry out the diagnosis of alarms efficiently and quickly. The model is divided into two main parts: (1) a protection system operation model; and (2) Unconstrained Binary Programming (UBP) model. Part (1) provides a set of expected state equations of the protective relay functions established based on the protection operation logic such as overcurrent, differential and distance as well as the protection philosophy. Part (2) is established through an objective function formulated based on parsimonious set covering theory for associating the alarms reported by SCADA (Supervisory Control and Data Acquisition) system with the expected states of the protective relay functions. The novel genetic algorithm use only two control parameters and is employed to minimize the UBP model. In addition the algorithm has recombination and mutation rates automatically and dynamically calibrated based on the saturation of the current population and it presents an immediate response to possible premature convergence to local optima. The methodology developed for the diagnosis of substations is extended to distribution networks considering that the network has sufficient level of automation for remote monitoring of the primary feeders. In this way a new paradigm for protection of distribution networks developed based on Smart Grid concept is proposed. Extensive tests are performed with the methodology applied to distribution... (Complete abstract click electronic access below) / Doutor
185

Aplica??o da t?cnica de self healing na reconfigura??o autom?tica de redes el?tricas utilizando o padr?o IEC 61850

Fonseca, Jonatha Revoredo Leite da 06 July 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2018-02-15T13:47:25Z No. of bitstreams: 1 JonathaRevoredoLeiteDaFonseca_DISSERT.pdf: 6647169 bytes, checksum: 89682e384a5fef047471acede0d629b4 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2018-02-20T21:24:35Z (GMT) No. of bitstreams: 1 JonathaRevoredoLeiteDaFonseca_DISSERT.pdf: 6647169 bytes, checksum: 89682e384a5fef047471acede0d629b4 (MD5) / Made available in DSpace on 2018-02-20T21:24:35Z (GMT). No. of bitstreams: 1 JonathaRevoredoLeiteDaFonseca_DISSERT.pdf: 6647169 bytes, checksum: 89682e384a5fef047471acede0d629b4 (MD5) Previous issue date: 2017-07-06 / Este trabalho tem como objetivo propor uma Smart Grid composta por duas subesta??es para a implanta??o da t?cnica de self healing utilizando o Simulador Digital em Tempo Real (RTDS ? Real Time Digital Simulator) e rel?s de prote??o IEDs (Intelligent Electronic Devices) com comunica??o atrav?s da padr?o IEC 61850 entre eles. Nas redes el?tricas de distribui??o, t?cnicas de recomposi??o autom?tica (self healing) podem ser usadas com o intuito de diminuir os tempos com a perda do fornecimento de energia el?trica aos consumidores ocasionado por curto-circuito, diminuindo assim os preju?zos aos consumidores e em decorr?ncia de multas. A metodologia aplicada ? baseada na modelagem do circuito proposto no RTDS, que ? monitorado em tempo real. S?o simulados v?rios tipos de curtos-circuitos em diferentes pontos do sistema e, na ocorr?ncia de cada falta gerada, o programa desenvolvido analisa os dados do sistema pr? e p?s falta, isolando o trecho do circuito afetado e ir? reconfigurar automaticamente a rede de forma a restabelecer o fornecimento de energia para as cargas afetadas. A escolha do arranjo final da rede, ap?s o processo de reconfigura??o autom?tica, ser? baseada em um processo de otimiza??o intitulado Reconfigura??o por Soma de Pot?ncias ? RSP. A comunica??o entre o RTDS e os IEDs (que fazem a prote??o de parte do sistema) utiliza o padr?o IEC 61850 com troca de mensagens GOOSE (Generic Object Oriented Substation Event) aplicando os aspectos relevantes desse padr?o. / This work aims to propose a Smart Grid composed of two substations for the implementation of the self healing technique using Real Time Digital Simulator (RTDS) and IED (Intelligent Electronic Devices) protection relays with communication through standard IEC 61850 between them. In distribution networks, self healing techniques can be used in order to reduce the times with the loss of electricity supply to consumers caused by a short circuit, thus reducing the losses to consumers and due to fines. The methodology applied is based on the proposed circuit modeling in the RTDS, which is monitored in real time. Several types of short circuits are simulated at different points in the system and, in each fault generated, the program developed analyze the pre and post fault system data, isolating the section affected and automatically reconfiguring the circuit to restore the power supply to the affected loads. The choice of the final network arrangement, after the automatic reconfiguration process, is based on an optimization process called Reconfiguration by Power Addition - RPA .Communication between RTDS and IEDs (which protect part of the system) use the IEC 61850 standard with GOOSE (Generic Object Oriented Substation Event) message exchange applying the relevant aspects of this standard.
186

Uma proposta de arquitetura extensível para micro medição em Smart Appliances

Torri, Lucas Bortolaso January 2012 (has links)
O sistema de energia atual passou por poucas alterações desde sua concepção original, há mais de 100 anos. No entanto, a crescente complexidade da infraestrutura e da demanda global por energia vem criando diversos desafios que a sua constituição original não previa, culminando em problemas como apagões e outras falhas no seu fornecimento. Além disso, nota-se nos últimos anos, principalmente nos países desenvolvidos, uma certa diversificação na matriz energética, incentivando a utilização de fontes de energia renováveis e distribuídas. Isto se deve não apenas ao potencial energético das, mas também visando uma menor utilização de combustíveis fósseis, devido tanto a volatilidade e tendência de alta dos preços do petróleo, mas também pela necessidade de contenção do volume de emissões de gases causadores do efeito estufa. Apesar desta defasagem do sistema de energia contemporâneo, avanços nas áreas de informática, eletrônica embarcada, além das tecnologias empregadas na construção de sensores e atuadores, têm possibilitado a criação de uma rede de energia moderna, automatizada e distribuída. Esta rede, conhecida como Mart Grid, traz novas perspectivas no gerenciamento e na operação dos sistemas de geração, transmissão e distribuição de energia elétrica, inserindo propostas que visam melhorar diversos fatores da rede de energia atual, aumentado sua eficiência, segurança e confiabilidade de transmissão, além da eliminação de obstáculos para a integração em larga escala de fontes de energia distribuídas e renováveis. Este novo paradigma é caracterizado por um fluxo bidirecional de eletricidade e de informações, afim de criar uma rede automatizada e distribuída de energia. Ele incorpora à grade os benefícios da computação distribuída e de comunicações para fornecer informações em tempo real e permitir o equilíbrio quase instantâneo da oferta e da procura dos bens energéticos. Dentro do contexto de Smart Grids, Smart Appliances são uma modernização dos aparelhos eletrodomésticos quanto a sua utilização de energia, de forma que estes sejam capazes de monitorar, proteger e ajustar automaticamente o seu funcionamento às necessidades do proprietário e a disponibilidade deste recurso. Ou seja, estes possuem não apenas características de inteligência, mas também a capacidade de utilizarem as informações disponibilizados no Smart Grid para adaptar seu funcionamento. Apesar do grande interesse despertado em torno destes conceitos, há ainda uma enorme carência de padrões e tecnologias que permitam a criação de tais aparelhos inteligentes inseridos nos ambientes domésticos e prediais. Este trabalho tem por objetivo estudar e conceituar o Smart Grid, pesquisando os grupos existentes que buscam uma padronização deste, bem como conceituar Smart Appliances, avaliando projetos e pesquisas existentes, e, principalmente, propondo uma arquitetura que permita a construção de tais dispositivos. Os requisitos necessários para a criação desta arquitetura são discutidos ao longo da dissertação, bem como as tecnologias necessárias e existentes para permitir sua proposta. Finalmente, o funcionamento bem sucedido, através de uma implementação da mesma, é demonstrado através de diferentes experimentos, avaliando como as características do Smart Grid podem ser utilizadas para criar aparelhos eletrodomésticos capazes de usarem as informações disponíveis para melhorar seu funcionamento. / Since its original conception, for over 100 years, the current energy system has experienced little changes. However, the increasing complexity of the infrastructure, together with the growing global demand for energy, have imposed many challenges that its original constitution did not foresee, which has resulted in problems such as blackouts along with other energy supply failures. Moreover, over the last few years, some diversification in energy generation has been seen, especially in developed countries, encouraging the use of distributed and renewable energy sources. Apart from the energetic potential offered by those sources, it aims to decrease the greenhouse gases emission volume, in addition to reduce dependency on fossil fuels, which tend to increase in price. Despite the lack of upgrades, improvements in the areas of computing, embedded electronics, and technologies employed in sensors and actuators assembly have enabled the creation of a modern automated and distributed power grid. This grid, better known as Smart Grid, enhances several factors of the current power network, bringing new perspectives in electricity management, operation, generation, transmission and distribution. That result in increased efficiency, transmission safety and reliability, additionally eliminating obstacles in large-scale integration of renewable and distributed energy sources. This new paradigm also features a bi-directional electricity and information flow, enabling an automated and distributed energy network that incorporates the grid benefits of distributed computing and communications to provide real-time information and allowing almost instantaneous supply and demand balance of energy goods. Within the context of Smart Grids, Smart Appliances proposes an extension of regular appliances with intelligence and self-awareness of their energy use, so that they are able to monitor, protect and automatically adjust its operation according to the owner's needs and availability of this resource. That is, besides of being smart, they feature ability to use the information available on the Smart Grid to adapt its running behavior. Even though the increased interest around these concepts, there is still a gap of standards and technologies enabling the creation and embedding of intelligent devices in residences and buildings. The present projects attempts to study and conceptualize Smart Grid, surveying existing standardization groups, as well as conceptualize Smart Appliances, evaluating existing projects and research, proposing an architecture allowing the building of such devices. The requirements for this architecture, together with the required and existing technologies to make the implementation feasible, are discussed throughout the project development. Finally, the architecture's successful functioning is demonstrated through an implementation of it, together with different experiments, relying on them to evaluate the Smart Grid characteristics and how appliances can improve their operation based on the information shared throughout the Smart Grid.
187

State Estimation for Enhanced Monitoring, Reliability, Restoration and Control of Smart Distribution Systems

January 2012 (has links)
abstract: The Smart Grid initiative describes the collaborative effort to modernize the U.S. electric power infrastructure. Modernization efforts incorporate digital data and information technology to effectuate control, enhance reliability, encourage small customer sited distributed generation (DG), and better utilize assets. The Smart Grid environment is envisioned to include distributed generation, flexible and controllable loads, bidirectional communications using smart meters and other technologies. Sensory technology may be utilized as a tool that enhances operation including operation of the distribution system. Addressing this point, a distribution system state estimation algorithm is developed in this thesis. The state estimation algorithm developed here utilizes distribution system modeling techniques to calculate a vector of state variables for a given set of measurements. Measurements include active and reactive power flows, voltage and current magnitudes, phasor voltages with magnitude and angle information. The state estimator is envisioned as a tool embedded in distribution substation computers as part of distribution management systems (DMS); the estimator acts as a supervisory layer for a number of applications including automation (DA), energy management, control and switching. The distribution system state estimator is developed in full three-phase detail, and the effect of mutual coupling and single-phase laterals and loads on the solution is calculated. The network model comprises a full three-phase admittance matrix and a subset of equations that relates measurements to system states. Network equations and variables are represented in rectangular form. Thus a linear calculation procedure may be employed. When initialized to the vector of measured quantities and approximated non-metered load values, the calculation procedure is non-iterative. This dissertation presents background information used to develop the state estimation algorithm, considerations for distribution system modeling, and the formulation of the state estimator. Estimator performance for various power system test beds is investigated. Sample applications of the estimator to Smart Grid systems are presented. Applications include monitoring, enabling demand response (DR), voltage unbalance mitigation, and enhancing voltage control. Illustrations of these applications are shown. Also, examples of enhanced reliability and restoration using a sensory based automation infrastructure are shown. / Dissertation/Thesis / Ph.D. Electrical Engineering 2012
188

The future of sustainable society – The state of the art of renewable energy and distribution systems

Bhatti, Harrison John January 2018 (has links)
Today society is facing numerous challenges associated with energy management system. The centralized power generation system is depending on the fossil fuels to generate energy which is harmful to the environment, and it is unable to fulfill the rising demand for electricity. The decentralized power generation system could easily be integrated with renewable energy sources which could satisfy the growing demand for electricity without damaging the environment. This thesis explores the proper energy distribution system (smart grid) which could be fully equipped with the digitalized technology and be integrated with renewable energy sources and decentralized system. Peer-reviewed articles and government reports have been reviewed in order to get the impact of digitalized technology on overall energy management system, as well as the smart grid services commercialized through the business models. The result shows that the cost of transmission lines is reduced by using decentralized power generation system which helps to provide clean energy at low price to the end consumers. Furthermore, the thesis claims that smart grid is a disruptive technology which encourages energy producers and distributors to adopt a rapid change in the energy market along with changing their business model.  Finally, it has been explored that smart grid could provide three services, such as demand response, integration of renewable energy, and grid to vehicle services. These services could successfully be commercialized through business model innovation which enables energy providing and distributing firms to create and capture value regarding profit. / <p>Thanks for the great support who were involved in the completion of this project.</p>
189

Uma proposta de arquitetura extensível para micro medição em Smart Appliances

Torri, Lucas Bortolaso January 2012 (has links)
O sistema de energia atual passou por poucas alterações desde sua concepção original, há mais de 100 anos. No entanto, a crescente complexidade da infraestrutura e da demanda global por energia vem criando diversos desafios que a sua constituição original não previa, culminando em problemas como apagões e outras falhas no seu fornecimento. Além disso, nota-se nos últimos anos, principalmente nos países desenvolvidos, uma certa diversificação na matriz energética, incentivando a utilização de fontes de energia renováveis e distribuídas. Isto se deve não apenas ao potencial energético das, mas também visando uma menor utilização de combustíveis fósseis, devido tanto a volatilidade e tendência de alta dos preços do petróleo, mas também pela necessidade de contenção do volume de emissões de gases causadores do efeito estufa. Apesar desta defasagem do sistema de energia contemporâneo, avanços nas áreas de informática, eletrônica embarcada, além das tecnologias empregadas na construção de sensores e atuadores, têm possibilitado a criação de uma rede de energia moderna, automatizada e distribuída. Esta rede, conhecida como Mart Grid, traz novas perspectivas no gerenciamento e na operação dos sistemas de geração, transmissão e distribuição de energia elétrica, inserindo propostas que visam melhorar diversos fatores da rede de energia atual, aumentado sua eficiência, segurança e confiabilidade de transmissão, além da eliminação de obstáculos para a integração em larga escala de fontes de energia distribuídas e renováveis. Este novo paradigma é caracterizado por um fluxo bidirecional de eletricidade e de informações, afim de criar uma rede automatizada e distribuída de energia. Ele incorpora à grade os benefícios da computação distribuída e de comunicações para fornecer informações em tempo real e permitir o equilíbrio quase instantâneo da oferta e da procura dos bens energéticos. Dentro do contexto de Smart Grids, Smart Appliances são uma modernização dos aparelhos eletrodomésticos quanto a sua utilização de energia, de forma que estes sejam capazes de monitorar, proteger e ajustar automaticamente o seu funcionamento às necessidades do proprietário e a disponibilidade deste recurso. Ou seja, estes possuem não apenas características de inteligência, mas também a capacidade de utilizarem as informações disponibilizados no Smart Grid para adaptar seu funcionamento. Apesar do grande interesse despertado em torno destes conceitos, há ainda uma enorme carência de padrões e tecnologias que permitam a criação de tais aparelhos inteligentes inseridos nos ambientes domésticos e prediais. Este trabalho tem por objetivo estudar e conceituar o Smart Grid, pesquisando os grupos existentes que buscam uma padronização deste, bem como conceituar Smart Appliances, avaliando projetos e pesquisas existentes, e, principalmente, propondo uma arquitetura que permita a construção de tais dispositivos. Os requisitos necessários para a criação desta arquitetura são discutidos ao longo da dissertação, bem como as tecnologias necessárias e existentes para permitir sua proposta. Finalmente, o funcionamento bem sucedido, através de uma implementação da mesma, é demonstrado através de diferentes experimentos, avaliando como as características do Smart Grid podem ser utilizadas para criar aparelhos eletrodomésticos capazes de usarem as informações disponíveis para melhorar seu funcionamento. / Since its original conception, for over 100 years, the current energy system has experienced little changes. However, the increasing complexity of the infrastructure, together with the growing global demand for energy, have imposed many challenges that its original constitution did not foresee, which has resulted in problems such as blackouts along with other energy supply failures. Moreover, over the last few years, some diversification in energy generation has been seen, especially in developed countries, encouraging the use of distributed and renewable energy sources. Apart from the energetic potential offered by those sources, it aims to decrease the greenhouse gases emission volume, in addition to reduce dependency on fossil fuels, which tend to increase in price. Despite the lack of upgrades, improvements in the areas of computing, embedded electronics, and technologies employed in sensors and actuators assembly have enabled the creation of a modern automated and distributed power grid. This grid, better known as Smart Grid, enhances several factors of the current power network, bringing new perspectives in electricity management, operation, generation, transmission and distribution. That result in increased efficiency, transmission safety and reliability, additionally eliminating obstacles in large-scale integration of renewable and distributed energy sources. This new paradigm also features a bi-directional electricity and information flow, enabling an automated and distributed energy network that incorporates the grid benefits of distributed computing and communications to provide real-time information and allowing almost instantaneous supply and demand balance of energy goods. Within the context of Smart Grids, Smart Appliances proposes an extension of regular appliances with intelligence and self-awareness of their energy use, so that they are able to monitor, protect and automatically adjust its operation according to the owner's needs and availability of this resource. That is, besides of being smart, they feature ability to use the information available on the Smart Grid to adapt its running behavior. Even though the increased interest around these concepts, there is still a gap of standards and technologies enabling the creation and embedding of intelligent devices in residences and buildings. The present projects attempts to study and conceptualize Smart Grid, surveying existing standardization groups, as well as conceptualize Smart Appliances, evaluating existing projects and research, proposing an architecture allowing the building of such devices. The requirements for this architecture, together with the required and existing technologies to make the implementation feasible, are discussed throughout the project development. Finally, the architecture's successful functioning is demonstrated through an implementation of it, together with different experiments, relying on them to evaluate the Smart Grid characteristics and how appliances can improve their operation based on the information shared throughout the Smart Grid.
190

Development of Operational Strategies for a Heating Pump System with Photovoltaic, Electrical and Thermal Storage / Utveckling av operativa strategier för ett värmepumpsystem med PV, elektrisk och termisk lagring

Leppin, Lorenz January 2017 (has links)
This study describes the development of operational strategies for an exhaust air heat pump system that supplies space heating and domestic hot water. The system combines photovoltaic power production with two different storage types. These are electrical storage using batteries and thermal storage in using a domestic hot water tank and in form of the thermal capacity of the building. The investigation of the control strategies is carried out for a detailed single family house model in Sweden in the simulation software TRNSYS. The overall aim of the control strategies is to improve the performance of the energy system in terms of self-consumption, self-sufficiency, final energy and seasonal performance factor. Three algorithms are developed and compared to a base case without additional control. The first algorithm only uses the thermal storage in the hot water tank and the building. The second uses only the battery to store the photovoltaic electricity. The third control algorithm combines both storage types, electrical and thermal. The simulation results show that for the studied system the energetic improvement is higher with the use of electrical storage compared to using thermal storage. The biggest improvement however is reached with the third algorithm, using both storage types in combination. For the case of a photovoltaic-system with 9 kW and battery store with 10.8 kWh and a 180 l hot water store the self-consumption reaches up to 51% with a solar fraction of 41 %. The reduction in final energy consumption for this case is 3057 kWh (31 %) with the heat pump having a seasonal performance factor of 2.6. The highest self-consumption is reached with a photovoltaic-system of 3 kW and battery store with 3.6 kWh, which comes to 71 %.

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