Orientador: Anna Diva Plasencia Lotufo / Resumo: This work analysis load data from desegregated levels that presented difficulties to load forecasting with several methods due to variation in electrical energy consumption. The application proposed in this work is short-term load forecasting to a university building by GRNN (General Regression Neural Network) considering the bottom up approach and using a moving average filter to deal with the missing or wrong data. It is presented the system that provides the data as well as the methods used for pre-processing and realize the forecasting. The results are evaluated by MAPE (Mean Absolute Perceptual Error) and are considered good when compared with other methods. / Mestre

Submitted by ANDRÉ LUIZ LATANSIO DE OLIVEIRA null (andrelatansio@gmail.com) on 2017-08-03T12:48:20Z No. of bitstreams: 1 dissertacao_final_submeter.pdf: 6036596 bytes, checksum: debf9708c542db4157e83657c0859084 (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-08-03T17:52:18Z (GMT) No. of bitstreams: 1 oliveira_all_me_ilha.pdf: 6036596 bytes, checksum: debf9708c542db4157e83657c0859084 (MD5) / Made available in DSpace on 2017-08-03T17:52:18Z (GMT). No. of bitstreams: 1 oliveira_all_me_ilha.pdf: 6036596 bytes, checksum: debf9708c542db4157e83657c0859084 (MD5) Previous issue date: 2017-07-07 / A simulação de ambientes computacionais é uma das principais técnicas para estudo de protocolos, seu comportamento em redes de computadores e análise da segurança da informação. O acesso a ambientes reais para simulação de smart grids está restrito a poucas universidades e empresas assim como existem poucas ferramentas disponíveis para sua simulação computacional, o que dificulta a realização de pesquisas nesta linha. Neste trabalho objetiva-se a configuração de um ambiente para simulação do protocolo DNP3 utilizando exclusivamente ferramentas open source, utilizando-se técnicas de segurança ofensiva para realizar ataques a rede e então validar o comportamento da simulação e por fim realizar a integração do ambiente de simulação com equipamentos reais. Para isso, foi desenvolvido um testbed virtual através da integração e configuração de diversas ferramentas e softwares open source e posteriormente utilizados os equipamentos do Laboratório de Proteção do Campus III na UNESP de Ilha Solteira, expandindo as funcionalidades do simulador e obtendo um testbed misto com resultados promissores em todos os testes realizados. / The simulation of computational environments is one of the main techniques applied in the study of protocols, the behavior of those protocols in computer networks, and the analysis of information security procedures. Research in the area of smart grid simulation is hampered by the fact that few universities and companies have access to real environments, and further, that the number of computational tools available is limited. This paper therefore aims to configure an environment for the simulation of the DNP3 protocol using exclusively open source tools and by applying offensive security techniques including attacks which seek to exploit network vulnerabilities; subsequently, the proposed simulation behavior is validated. For this purpose, a virtual testbed was developed by integrating and configuring various open source software and tools and later using the Campus III Protection Laboratory equipments at UNESP Ilha Solteira, expanding the simulator functionalities and obtaining a mixed testbed with results promising in all tests performed.

Redes elétricas desempenham um papel fundamental no que tange à distribuição de energia elétrica. Entretanto, as redes elétricas convencionais são muito antigas, apresentando uma série de deficiências e inseguranças. Neste cenário surgem as redes elétricas inteligentes, mais conhecidas como smart grids. Smart grids são uma evolução para as redes elétricas tradicionais, apresentando como grande diferencial a presença intensiva de tecnologia de ponta para monitorar cada elemento que a compõe. Uma das principais características de smart grids é seu fluxo bidirecional de energia e informação, que permite a qualquer elemento tanto consumir quanto fornecer energia para a rede, seja um aerogerador ou mesmo uma residência. Tal característica vai de encontro à necessidade de se distribuir a produção energética, tornando-a mais robusta e tolerante a falhas. Uma tecnologia que surgiu em meio ao desenvolvimento de smart grids denomina-se Veículo-Para-Rede (V2G, do inglês Vehicle-To-Grid). Através de sessões V2G, veículos elétricos (EVs, em inglês electric vehicles) podem vender a energia de suas baterias para a rede, obtendo lucro com este procedimento. Existem duas vantagens nesta tecnologia. Por um lado, proprietários de EVs podem obter lucro com a venda de energia, reduzindo os custos de se manter seu veículo. Por outro lado, a rede como um todo se beneficia, pois as baterias podem ser utilizadas para aumentar a estabilidade da rede. Entretanto, para que estas vantagens sejam expressivas, é necessário utilizar-se de mecanismos para aumentar a eficiência do processo V2G, uma vez que baterias são muito caras. Uma alternativa que tem sido muito explorada é a formação de coalizões entre os EVs. A proposta deste trabalho é utilizar informações sobre o domínio de smart grids de modo a impor restrições no processo de formação de coalizões de EVs, visando à redução do espaço de busca de estruturas de coalizão. Especificamente, estabelece-se a distância máxima que pode haver entre dois EVs de uma mesma coalizão, através da qual é possível identificar e podar porções inválidas do espaço de busca. Para tanto, é proposto o algoritmo CPCSG, capaz de identificar restrições entre os EVs e de podar o espaço de busca. A abordagem proposta pode ser utilizada em conjunto com algoritmos de geração de estruturas de coalizão para torná-los mais rápidos e eficientes. Com base em experimentos, percebe-se que a abordagem proposta proporciona um ganho notável de desempenho e uma redução expressiva no uso de memória em relação a outros algoritmos para geração de estruturas de coalizão. Em geral, quanto mais restritiva a rede e quanto maior o número de agentes, maior será o percentual do espaço de busca passível de ser podado. Resultados mostram, ainda, que quando comparada com outros algoritmos de geração de estruturas de coalizão, a técnica proposta chega a superar o tempo dos demais em diversas ordens de magnitude. / Electric grids play a key role in the energy distribution process. However, conventional grids are very old, which causes the onset of weaknesses and uncertainties. In such a scenario the smart grid concept arises. Smart grids are an evolution to the ageing electric grids, whose major breakthrough is the intensive use of technology to monitor every element that comprises it. One of the main features of smart grids is its bi-directional flow of electricity and information, which allows any element to consume and even supply energy to the grid, regardless of being a wind turbine or even a residence. Such a characteristic meets the need to make the energy production more distributed, making it more robust and fault tolerant. Amidst the development of smart grids emerged the concept of Vehicle-To-Grid (V2G). Through V2G sessions, electric vehicles (EVs) can sell the surplus energy of their batteries to the grid, making a profit. Two advantages arise from this technology. First, EVs’ owners can make a profit from the sale of energy, reducing their vehicles’ maintenance cost. Second, the network as a whole is benefited as batteries could be used to increase the network stability. However, in order to benefit from such advantages, it is necessary the use mechanisms to increase the efficiency of the V2G process, since batteries are very expensive. One way that has been explored is the coalition formation among EVs. The proposal of this work is to use smart grids’ domain information to impose constraints on the coalition formation process in order to reduce the coalition structures’ search space. Specifically, we define a maximum distance that can exist between two EVs of a given coalition, through which it is possible to identify and prune invalid portions of the search space. To this end, we propose the CPCSG algorithm, which has the capability of identifying constraints among EVs and pruning the search space. The proposed approach can be used together with coalition structure generation algorithms to make them faster and more efficient. Based on experiments, it can be seen that our approach provides a noticeable performance gain and a significant memory usage reduction compared to other coalition structure generation algorithms. In general, the more restrictive the grid and the greater the number of agents, the greater the percentage of the search space that can be pruned. Results also show that when compared with other coalition structure generation algorithms, the proposed technique is able to overcome the other in time by several orders of magnitude.

CoordenaÃÃo de AperfeiÃoamento de NÃvel Superior / In the context of the current modernization process through which the electrical power systems go through, the concept of Smart Grids and their foundations serve as guidelines. In the search for interoperability, communication between heterogeneous systems has been the subject of constant and increasing developments. Under this scenario, the work presented in this dissertation focuses primarily on the study and application of the data model contained in the IEC 61970 series of standards, best known as the Common Information Model (CIM). With this purpose, the general aspects of the standard are exposed and assisted by the concepts of UML and XML, which are essential for a complete understanding of the model. Certain features of the CIM, as its extensibility and generality are emphasized, which qualify it as ideal data model for the establishment of interoperability. In order to exemplify the use of the model, a case study was performed which modeled an electrical distribution network in medium voltage so as to make it suitable for integration with a multi-agent system in a standardized format and, consequently, adequate to interoperability. The complete process of modeling an electrical network using the CIM is shown. Finally, the development of an interface is proposed as a mechanism that enables human intervention in the data flow between the integrated systems. The use of PHP with a MySQL database, are justified because of their suitability in various usage environments. / No processo atual de modernizaÃÃo pelo qual passam os sistemas de energia elÃtrica, o conceito de Redes ElÃtricas Inteligentes e seus fundamentos tÃm servido de diretrizes. Na busca pela interoperabilidade, a comunicaÃÃo entre sistemas heterogÃneos tem sido objeto de constantes e crescentes avanÃos. Este trabalho tem como objetivo o estudo e a aplicaÃÃo do modelo de dados da sÃrie de normas IEC 61970, denominado Common Information Model (CIM). Com esse objetivo, os aspectos gerais da norma sÃo apresentados, auxiliados pelos conceitos de UML (Unified Modeling Language) e XML (eXtensible Markup Language), essenciais para a compreensÃo integral do modelo. Determinadas caracterÃsticas do modelo CIM, como sua extensibilidade e generalidade, sÃo enfatizadas, as quais o credenciam como modelo com excelentes caracterÃsticas para o estabelecimento da interoperabilidade. Com o intuito de exemplificar a utilizaÃÃo do modelo, realizou-se um estudo de caso em que se modelou uma rede elÃtrica de distribuiÃÃo em mÃdia tensÃo de maneira a tornÃ-la prÃpria para integraÃÃo com um sistema multiagente em um formato padronizado e, consequentemente, adequado à interoperabilidade. O processo completo de modelagem da rede elÃtrica utilizando o CIM foi demonstrado. Por fim, uma interface foi desenvolvida como mecanismo de manipulaÃÃo dos dados nos documentos XML que possam fazer parte do fluxo de informaÃÃes. A utilizaÃÃo do PHP, juntamente com um banco de dados MySQL, à justificada em decorrÃncia de sua adequaÃÃo de uso em ambientes diversos. Os conjuntos formados pela interface, simulador da rede elÃtrica e sistema multiagente para recomposiÃÃo automÃtica, constituÃram um sistema cujas informaÃÃes foram plenamente integradas.

The goal of the Master´s thesis is to map the actual situation of transformation of power energy sector to smart grid, find answers to some of the major questions concerning the implementation of smart metering systems, evaluate societal and economic costs and benefits, evaluate trends in legislation, compare the situation in Slovakia with other peer countries from the European Union, and create a follow-up recommendations for Slovakia based on this assessment. The thesis includes detailed critical analysis of the CBA, originally created for Slovakia, using benchmarking with countries with a different calculation approach. The used methodology in this work is a research of available resources, qualitative research of case studies, break-down of the CBA, and expert research through interviewing. The outcome is evaluation of economic and societal contributions of smart metering systems and mapping the process and state of the implementation.

The doctoral thesis proposes a synchronization event detection method suitable for establishing a common time base across devices using power-line communication. The technique facilitates the creation of a synchronization procedure for smart grid terminal devices, thus bringing to the low-voltage segment new functionalities already known from the higher voltage levels of the distribution network. High-precision, zero-cross line voltage detection was employed as the synchronization event. The use of the PLL (phase-locked loop) was considered and analyzed as a potentially applicable option; however, such a solution proved to be insufficiently robust against interference. Further, an FFT-based approach was designed and reviewed. The technique performs zero-cross detection, but only for the fundamental harmonic component that remains the same across the entire network. The influence of incoherent sampling on the FFT, too, was tested during the development of the method; in this context, coherent sampling was found to constitute an essential prerequisite for accurate detection as it allows us to eliminate the spectral leakage error. The impact of an AD converter on the detection accuracy was also evaluated. The proposed approach ensures the accuracy required for all common measurements and operations to improve the production, distribution, and consumption of electricity through smart grids.

Electric grid as we now it has been without significant change for a long time. Along with the human population grows demand for electricity, which leads to need to create more energy. Bigger interest is in ecology and use of renewable sources, although these do not have constant output which often stresses the grid. These problems are to be solved by smart grids. Smart grids are capable of adjusting energy generation to immediate demand including renewable sources to compensate energy fluctuations in grid. They provide demand response and other applications interesting for end users. Smart grids are combination of achievements in energy, informatics and communication technology. Communication, which is key part of smart grids, has to met certain requirements and can be executed by various technologies. There are described various communication technologies and a design concept of data communication in this paper.

El objetivo de la Tesis es mostrar, a partir de un balance energético dimensionable y contrastable, la viabilidad de un sistema de recarga de baterías de tracción de Vehículos Eléctricos de manera simultánea a la producción dentro de la llamada “ventana fotovoltaica”, como garantía de que la electricidad producida para la movilidad eléctrica no dependa de los combustibles fósiles que están inevitablemente presentes en el “share” energético global para, de esta manera, reducir el nivel de emisiones de CO2 a la atmósfera por parte del sector del transporte. Y el intercambio de baterías es presentado como la alternativa para resolver el problema de la simultaneidad entre la producción fotovoltaica y la utilización del vehículo, y para vencer la barrera del tiempo de recarga. Si el vehículo eléctrico está llamado a ser el sustituto natural del convencional y las energías renovables están llamadas a ser las sustitutas naturales de las convencionales, es necesario comprobar la viabilidad del binomio “Vehículo Eléctrico - Energías Renovables” y el desarrollo conjunto de ambas. Siendo una realidad que el Vehículo Eléctrico ya es un producto al alcance del gran público, no es menos cierto que el grado de penetración del mismo está teniendo lugar a un nivel infinitamente inferior al esperado, en parte como consecuencia del elevado coste del VE y la situación económica global, en parte porque la usabilidad del VE y el vehículo convencional no es la misma al no disponer el VE de autonomía, tiempo de recarga e infraestructura de recarga comparables a su homólogo convencional, y en parte como consecuencia del mantenimiento del status-quo existente entre los fabricantes de vehículos y las empresas suministradoras de combustibles fósiles que intentan frenar lo máximo posible el proceso de electrificación del sector de transporte. Por otro lado, es también una realidad el drástico descenso en los costes de los equipos de producción de electricidad fotovoltaica en los últimos años, sobre todo los paneles solares y los onduladores DC-AC, de forma que cada Watio instalado viene a costar, en promedio, 5 veces menos que en 2007 y las instalaciones son rentables por sí mismas sin necesidad de mecanismos de subvención externos. Todo ello ha facilitado que a día de hoy dispongamos de un escenario de Balance Neto (Autoconsumo con intercambio con la red) viable que ha abierto la puerta a las Smart Grids en las cuales el punto de recarga del Vehículo Eléctrico es sin duda uno de los protagonistas del escenario futuro. Y puesto que tanto las instalaciones fotovoltaicas a pequeña escala como el vehículo eléctrico son 2 campos emergentes con mucho desarrollo todavía por delante, el autor ha querido relacionar ambos a nivel dimensional y justificar que el futuro crecimiento conjunto de ambos puede contribuir enormemente a la reducción progresiva de la emisión de gases contaminantes a la atmósfera por parte del sector del transporte.

The size and composition of the Swedish electricity generation are changing. This, in combination with new legal requirements from regulatory entities including the EU Directive 2019/944, creates several challenges for the design of the future system. Among other things, the directive suggests that flexibility solutions are to be integrated into grids to increase the degree of utilization and avoid congestions, when socio-economically profitable. This thesis evaluates what this could mean in a Swedish context, in combination with providing a basic understanding of the contradictions that can arise between a desired efficient grid use in an energy system that goes towards more distributed and intermittent energy generation sources. The work is carried out in collaboration with Vattenfall Eldistribution AB, focusing on the geographical area of Uppsala and Stockholm, the Swedish region hit hardest by local congestions. The work assumes that the economic value of a flexibility solution is at most equivalent to the cost of a conventional new construction aimed at capacity strengthening, or the Value of Lost Load (VoLL). The report’s most important deliverable is a model based on this view. The model is used to evaluate the economic value of flexibility per kWh, in three regional grid construction projects within the mentioned region.  The results show that there is a great potential for using flexibility resources to increase utilization in grids and also to optimize the costs that society pays for this infrastructure by such methods. However, the work concludes that the usage of flexible technologies primarily is to adapt electric consumption with intermittent energy generation, rather than being used to solve local grid capacity shortages.

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