Orientador: José Angelo Cagnon / Banca: Odivaldo José Seraphim / Banca: Mário Eduardo Bordon / Banca: José Pissolato Filho / Banca: Diogenes Pereira Gonzaga / Resumo: O presente trabalho teve como objetivo a análise do sistema de armazenamento de energia elétrica gerada a partir de um sistema fotovoltaico, composto por baterias de chumbo-ácido. A crescente demanda de energia no mundo, além da necessidade de utilização de recursos renováveis de forma a preservar o nosso meio ambiente, obriga o desenvolvimento de técnicas de eficiência na produção e controle dessa energia. A escassez apresentada atualmente na área energética ao redor do mundo chama a atenção de toda a comunidade científica que se preocupa em desenvolver projetos alternativos para suprir as necessidades do ser humano de um modo produtivo, não poluente e de baixo custo. Para o desenvolvimento desse trabalho, foram utilizados dois sistemas fotovoltaicos, o primeiro, convencional, com painel solar estacionária e o segundo com um sistema de posicionamento automático com relação ao sol. Esta análise comparativa permitirá avaliar as vantagens ou não de um sistema, em relação ao outro. Além disso, foram levantadas as curvas de carga, descarga, capacidade da bateria, determinação da taxa hora-funcional, a reação de auto-descarga (através do estado de flutuação) entre outras informações relevantes que permitam entre outras coisas, obter uma maior vida útil da bateria estacionária em questão. Esse trabalho levantará as características elétricas, como tensão, corrente, potência e energia, utilizará ferramentas de modelagem através de circuitos elétricos equivalentes para simulação do comportamento da bateria, em situações de carga e descarga, e principalmente o levantamento experimental das baterias funcionando nos dois sistemas distintos. Este trabalho evidencia as diferenças comportamento da bateria, e mostra a configuração que permite a operação da bateria em condições mais favoráveis. Os resultados obtidos, indicam que a bateria ligada... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This work aimed at analyzing the electric energy storage system generated from a photovoltaic system with lead-acid batteries. The increasing claim for energy in the world in addition to the need of utilizing renewable sources of energy in order to preserve the environment makes necessary the development of efficient techniques for energy generation and control. The energy shortage experienced in today's world attracts attention from the scientific community, which is concerned about developing alternative projects towards the human being's need in a productive way, without pollution and low cost. Two photovoltaic systems were used in this work, a conventional one with stationary solar panel and another with automatic solar position system. The comparative analysis has allowed assessing the advantages of both systems. The following characteristics were obtained during the development of this work: charge, discharge, battery capacity, operating time rate, auto-discharge reaction (through fluctuation state), among other important information that allowed to attain an extended life to the stationary battery studied. The characteristics described in the references of this work have been obtained, and modeling techniques through electric circuits were used to simulate the battery behavior for charge and discharge conditions. The experimental tests of the battery operation in both systems were carried out. This research has searched for showing the main differences of the battery behavior in order to get the configuration in which the battery operation is developed in more favorable conditions. / Doutor

Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2017-01-30T09:23:03Z No. of bitstreams: 2 Dissertação - Gustavo de Souza Neves - 2016.pdf: 2403103 bytes, checksum: e89c1c7d2a7ed732e3b4cd3a17b311ce (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-01-30T09:23:52Z (GMT) No. of bitstreams: 2 Dissertação - Gustavo de Souza Neves - 2016.pdf: 2403103 bytes, checksum: e89c1c7d2a7ed732e3b4cd3a17b311ce (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-01-30T09:23:52Z (GMT). No. of bitstreams: 2 Dissertação - Gustavo de Souza Neves - 2016.pdf: 2403103 bytes, checksum: e89c1c7d2a7ed732e3b4cd3a17b311ce (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-03-16 / Conventional means of transportation have a significant impact on people's lives, which depend on the current model to perform their routine activities. Families can expend up to 20% of their income on transport. On the other hand, internal combustion vehicles emit gases that impair nature, have low efficiency reaching a maximum 30% yield. In contrast, the electric vehicle has up to 90% efficiency and does not emit harmful gases directly. These factors contribute to the increase of financial and energy waste. This study aims to contribute to minimizing these impacts through analysis of an electric propulsion system of low cost, powered by photovoltaic source to be installed in a vehicle structure of PVC (Polyvinyl Chloride). The use of this renewable energy source enables the implementation of a photovoltaic power generation system, stored in lead acid batteries used in most of vehicles. After analysis of decision matrix, it was determined the most appropriate model that supports the proposal economically and evaluated electric DC motors found in conventional vehicles. These it was found that the engine of the windshield wipers can be used in vehicle propulsion system. To control the entire electrical system was used PIC micro controller, responsible for driving the motors through H bridge, consisting of MOSFET transistors. The simulation of this control system was held at the Proteus®. / Os meios de transportes convencionais têm impacto relevante na vida das pessoas, as quais dependem do modelo atual para realização de suas atividades rotineiras. Famílias de classe média dispendem até 20% de sua renda com transportes. Por outro lado, veículos de combustão interna emitem gases que contribuem para o efeito estufa, são de baixa eficiência, com no máximo 30% de aproveitamento. Em oposição, o veículo elétrico possui até 90% de eficiência e não emite gases de efeito estufa diretamente. Esses fatores contribuem com o aumento de desperdício financeiro e energético. Este estudo visa colaborar com a minimização destes impactos, por meio da análise de um sistema propulsor elétrico de baixo custo, alimentado por fonte fotovoltaica a ser instalado em um veículo de estrutura em PVC (Policloreto de Vinila). A utilização dessa fonte de energia renovável possibilita a implantação de um sistema de geração de energia fotovoltaica, armazenada em baterias de chumbo-ácido, utilizadas em veículos ã combustão. Após anáslise por matriz de decisão, foi determinado o modelo mais adequado que atende ã proposta de forma econômica e avaliados motores elétricos de corrente contínua, encontrados em veículos convencionais. Destes se verificou que os motores de limpadores de para-brisa podem ser empregados no sistema de propulsão do veículo. Para controlar todo o sistema elétrico foi utilizado o micro controlador PIC, responsável pelo acionamento dos motores através de ponte H, constituídas por transistores MOSFET. Foi realizada a simulaço desse sistema de controle no programa Proteus®.

Este trabalho propõe caracterizar a complementaridade espacial-temporal entre energia eólica e solar fotovoltaica entre regiões do Brasil e estudar, no âmbito da comercialização de energia elétrica no Setor Elétrico Brasileiro - SEB, se um portfólio formado por estas fontes trazem vantagens econômicas relevantes para o investidor. Para atender a estes objetivos, foram estudados métodos para tratamento dos dados como a correção da irradiância solar, cálculo da energia gerada pelas fontes estudadas, o ambiente de contratação de energia elétrica no Brasil, métodos de otimização e modelos de análise de risco para contratação de energia no mercado livre de energia. A metodologia proposta para responder as questões colocadas foi aplicada em um estudo de caso envolvendo três regiões brasileiras em um horizonte de dez anos. Concluiu-se que existe a complementaridade energética entre as fontes nas diferentes regiões estudadas e em diferentes períodos de tempo. Confirmou-se que tecnicamente pode-se reduzir a oscilação na geração de energia analisando as fontes de forma complementar, porém, o custo de instalação da fonte fotovoltaica ainda é muito alto, inviabilizando até o momento investimentos em larga escala e de forma complementar a fonte eólica. Também verificou-se, dentro dos locais avaliados, que somente um dos três locais apresentou benefício econômico-financeiro com a formação de portfólio das fontes eólica e solar atuando no mercado de venda de energia e atendendo os critérios de risco limite estabelecidos quando avaliadas segundo a ótica da maximização da receita no mercado livre. / This thesis proposes to characterize the spatial-temporal complementarity between wind and solar photovoltaic energy between regions of Brazil and study, in the marketing of electricity in the Brazilian Electrical Sector - SEB, a portfolio formed by these sources bring significant economic benefits to the investor. To meet these goals, methods for data processing were studied as correction of solar irradiance calculation of the energy generated by the sources studied, the environment of contracting electricity in Brazil, optimization methods and models for risk analysis for contracting energy in the free energy market. The proposed methodology to answer the questions was applied in a case study involving three Brazilian regions with a horizon of ten years time series. It was concluded that there is complementarity between energy sources in the different regions studied and in different time periods. It was confirmed that technically can reduce the fluctuation in power generation by analyzing the complement of sources, however, the installation cost of photovoltaic power is still too high, preventing yet large-scale investments and complementary way the source wind. Also it was found within the sites evaluated, only one of the three sites presented economic and financial benefit by the portfolio of wind and solar sources acting in the sale of energy market and considering the risk criteria limit established when evaluated according to perspective of maximizing revenue in the free energy market.

Este trabalho propõe um procedimento para qualificar sistemas fotovoltaicos conectados à rede, o qual possui dois focos principais: o comissionamento e a caracterização da produção de energia. Também resume alguns aspectos normativos relacionados aos sistemas fotovoltaicos, apresenta os principais parâmetros de desempenho utilizados para caracterizar um sistema fotovoltaico, propõe uma metodologia para calcular a energia injetada na rede, a qual incorpora modelos matemáticos e procedimentos de medição, tanto novos quanto convencionais, e aplica essa metodologia em um estudo de caso de um sistema fotovoltaico real. / This work proposes a procedure for qualifying grid-connected photovoltaic systems, which has two main focuses: the commissioning and the characterization of energy production. The work also summarizes some regulatory aspects related to photovoltaic systems, presents the main parameters used to characterize the performance of a photovoltaic system, proposes a methodology to calculate the energy injected into the grid, which incorporates both new and conventional mathematical models and measurement procedures, and applies this methodology to a case of study of a real photovoltaic system.

Made available in DSpace on 2017-07-10T17:11:45Z (GMT). No. of bitstreams: 1 DAVID RODRIGO FRANCO LEON2.pdf: 2087252 bytes, checksum: a70bd4795d62e855f534a86b2beafa7b (MD5) Previous issue date: 2013-11-29 / The increasing use of renewable energy to produce electricity, including photovoltaic, is an alternative used to meet growing electricity demand. Particularly, has been discussed the possibility of inserting these sources associated to loads, which is related with the concept of micro grids. A simulation model that allows to determine the behavior of the PV system, connected to the micro grid in different weather conditions, is essential to validate and predict future problems that may exist. Thus, this paper proposes a simulation model of a photovoltaic system, which includes the representation of the inverter and a bidirectional converter with storage unit, allowing the insertion of photovoltaic in a micro grid in steady state under different conditions of solar irradiation. The results show the behavior of the micro grid to different environment conditions of irradiation, different values of loadsconnected to the node generation and behavior of bidirectional converter, as in the storage of electrical for the conditions simulated. The behavior of the PV system as a source of energy within a micro grid was analyzed by simulating different load values, irradiation and electrical characteristics of the micro grid. / As fontes renováveis de energia para produção de energia elétrica, entre elas a que utiliza a tecnologia fotovoltaica, são alternativas utilizadas para atender a crescente demanda de energia elétrica. Particularmente vem sendo discutida a possibilidade de inserção dessas fontes junto às cargas, ao qual está associado o conceito de microrredes. Um modelo de simulação que permita determinar o comportamento do sistema fotovoltaico ao ser ligado à microrrede, em distintas condições ambientas, é fundamental para validar e prever futuros problemas que possam existir. Desta forma, o presente trabalho propõe um modelo de simulação de um sistema fotovoltaico, que inclui a representação do inversor e de um conversor bidirecional com unidade de armazenamento, que permite inserir a energia fotovoltaica numa microrrede elétrica em regime estacionário em distintas condições de irradiação solar. Os resultados mostram o comportamento da microrrede para distintas condições ambientais de irradiação, diferentes valores de cargas ligadas ao nó de geração e o comportamento do conversor bidirecional, quanto ao armazenamento ou não de energia para as condições simuladas. O comportamento do sistema fotovoltaico, como fonte de energia dentro de uma microrrede, foi analisado simulando diferentes valores de carga, irradição e características elétricas da microrrede.

Genetic algorithm has been widely used in different areas of optimization problems. Ithas been combined with renewable energy domain, photovoltaic system, in this thesis.To participate and win the solar boat race, a control program is needed and C++ hasbeen chosen for programming. To implement the program, the mathematic model hasbeen built. Besides, the approaches to calculate the boundaries related to conditionhave been explained. Afterward, the processing of the prediction and real time controlfunction are offered. The program has been simulated and the results proved thatgenetic algorithm is helpful to get the good results but it does not improve the resultstoo much since the particularity of the solar driven boat project such as the limitationof energy production

Today agriculture sector has a big contribution to the development of economy for many countries. Irrigation is a method which supplies amount of water required in proper time to the cropped land and contributes to the increases of agriculture productivity. Using diesel pump to deliver water to the place of use causes problems both in terms of profitability and environmental perspectives. Higher price of diesel increases operation costs of diesel water pumping system thereby reducing the incomes. In addition the use of diesel pump emits a huge amount of CO2 emissions which cause global warming. A possible solution to those problems is to use solar energy, a source of energy which is environmental friend and available for free. The main target of this thesis is to design and optimize a cost effective PVWPs considering three alternatives with tank storage, battery storage and a system without storages medium. The two areas in Eastern province of Rwanda were taken as case study to grow coffee and cassava with five hectares each. To run simulations, different tools have been used. Those includes CROPWAT to determine water requirements for two crops; MS Excel to design a PVWPs directly connected to irrigation system, make economic analysis, evaluate CO2 emissions and calculate other parameters. Furthermore in PVsyst software the design and simulation for PVWPs with storages medium has been carried out.  Results showed that using PVWPs directly connected to irrigation system is the most profitable way when compared to the rest two alternatives.  They also showed that systems designed to irrigate coffee becomes the most profitable due to huge amount of electricity surplus and higher price per kilogram of coffee. Finally fully replacement of DWPs results in annual reduction of CO2 emissions by 6.6 tonnes. Keywords: Photovoltaic system, storages medium, pumping system, economic analysis, reduction in CO2 emissions.

This research proposes an efficient reliability modeling and simulation methodology in power systems to include photovoltaic units, wind farms and storage. Energy losses by wake effect in a wind farm are incorporated. Using the wake model, wind shade, shear effect and wind direction are also reflected. For solar modules with titled surface, more accurate hourly photovoltaic power in a specific location is calculated with the physical specifications. There exists a certain level of correlation between renewable energy and load. This work uses clustering algorithms to consider those correlated variables. Different approaches are presented and applied to the composite power system, and compared with different scenarios using reliability analysis and simulation. To verify the results, reliability indices are compared with those from original data. As the penetration of renewables increases, the reliability issues will become more important because of the intermittent and non-dispatchable nature of these sources of power. Storage can provide the ability to regulate these fluctuations. The use of storage is investigated in this research. To determine the operating states and transition times of all turbines, Monte Carlo is used for system simulation in the thesis. A conventional power system from IEEE Reliability Test Systems is used with transmission line capacity, and wind and solar data are from National Climatic Data Center and National Renewal Energy Laboratory. The results show that the proposed technique is effective and efficient in practical applications for reliability analysis.

No description available.

Η εμπειρία έχει δείξει ότι στα αυτόνομα φωτοβολταϊκά συστήματα, η μπαταρία είναι το πιο αδύναμο στοιχείο αφού το προσδόκιμο ζωής της είναι συνήθως αρκετά μικρότερο από ότι όλων των άλλων στοιχείων του συστήματος και για το λόγο αυτό είναι και το πιο ακριβό στοιχείο με το 30% ή και περισσότερο του κόστους ενός αυτόνομου φωτοβολταϊκού συστήματος καθ’όλη τη διάρκεια της ζωής του να οφείλεται στο σύστημα αποθήκευσης. Αντικείμενο αυτής της εργασίας είναι η μελέτη των προβλημάτων που αντιμετωπίζουν οι μπαταρίες μολύβδου οξέος (που είναι ο βασικός τύπος μπαταριών που χρησιμοποιείται για την αποθήκευση στα φωτοβολταϊκά συστήματα) και οι τρόποι αντιμετώπισής τους με σκοπό αφενός την επέκταση της διάρκειας της χρήσιμης ζωής των μπαταριών αυτών και αφετέρου τη μείωση του κόστους συντήρησης και αντικατάστασής τους. Ιδιαίτερη βαρύτητα δίνεται στο πρόβλημα της θειίκωσης, το οποίο έχει αποδειχθεί ο σημαντικότερος παράγοντας γήρανσης και τελικά καταστροφής της πλειοψηφίας των μπαταριών μολύβδου οξέος που χρησιμοποιούνται στα φωτοβολταϊκά συστήματα και παρουσιάζονται τεχνικές που μπορούν να χρησιμοποιηθούν για την πρόληψη και την αντιμετώπιση του πολύ σοβαρού αυτού προβλήματος. / Experience has shown that in stand alone photovoltaic systems, battery is the weakest element since its expected lifetime is usually considerably smaller than those of other elements. Thus its cost is the most expensive with 30% or above of the total cost of stand alone photovoltaic system throughout its whole lifespan. Subject of this dissertation is the study of problems that lead acid batteries face and the way to treat them. The aim is to extend their useful lifetime and the reduction of the cost of maintenance and replacement. The problem of sulphation is given special importance, since it has been proved that it constitutes the main aging factor for the majority of lead acid batteries used in photovoltaic systems. Suggestions for treatment are given.