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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.
21

Sistema autônomo de bombeamento de água acionado por painéis fotovoltaicos amorfo e policristalino / Autonomous water pumping system powered by amorphous and polycristalline photovoltaic panels

Zilli, Bruno Meneghel 19 February 2018 (has links)
Submitted by Rosangela Silva (rosangela.silva3@unioeste.br) on 2018-06-26T14:28:30Z No. of bitstreams: 2 Bruno_Meneghel_Zilli.pdf: 2648925 bytes, checksum: 08fd69f79ec208d953d18a5a99774857 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-06-26T14:28:30Z (GMT). No. of bitstreams: 2 Bruno_Meneghel_Zilli.pdf: 2648925 bytes, checksum: 08fd69f79ec208d953d18a5a99774857 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-02-19 / Fundação Araucária de Apoio ao Desenvolvimento Científico e Tecnológico do Estado do Paraná (FA) / Water resources have fundamental importance both for life of living beings and for human activities. The lack of water can be a limiting factor for occupation and development of a certain region. Pumping systems are an alternative solution for these cases, with electric generation from photovoltaic panels being a locally pollutant-free option with less maintance when compared to combustion-generation engines. This work aims the analysis of a photovoltaic pumping system with two cell technologies, amorphous silicon and polycrystaline. The experiment was installed in the dependencies of the State University of West Paraná – campus Cascavel-PR. The data of voltage and electric current generated by panels, ambient and panels temperature, solar irradiation and water flow were collected. From these data, the volume pumped in the establised period, the flow as a function of the irradiation and the energy consumed, the behavior of the available and consumed energies, as well as the panel’s temperature on efficiency, were analyzed. The average volume pumped was 2,255.44 and 2,397.01 liters per day in the amorphous and polycrystalline systems, respectively. The best efficiency results in both systems were given at 800 W m-2, 4,69% for amorphous and 7,75% polycrystaline. However, the firt one presented lower voltage drop with panel’s temperature increasing. It was obtained higher flow and overall efficiency in the polycrystalline system. / Os recursos hídricos são de fundamental importância tanto para a vida dos seres vivos, quanto para as atividades antrópicas. A falta destes pode ser um fator limitante para a ocupação e desenvolvimento de uma determinada região. Sistemas de bombeamento de água são uma alternativa para solução destes casos, sendo a geração elétrica a partir de painéis fotovoltaicos uma opção localmente sem poluentes e com menos manutenção quando comparado a moto geradores à combustão. Este trabalho visa a análise de um sistema de bombeamento fotovoltaico com duas diferentes tecnologias de células, silício amorfo e policristalino. O mesmo foi instalado nas dependências da Universidade Estadual do Oeste do Paraná – campus Cascavel-PR. Coletou-se os dados da tensão e corrente elétrica gerados pelos painéis, temperatura ambiente e dos painéis, irradiação solar e vazão da bomba d’água. A partir destes, foram avaliados o volume bombeado no período estabelecido, a vazão em função da irradiação e da energia consumida, o comportamento das energias disponível e consumida, assim como a influência da irradiação e da temperatura do painel sobre a eficiência do mesmo. O volume médio bombeado foi de 2.255,44 e 2.397,01 litros por dia nos sistemas amorfo e policristalino, respectivamente. Os melhores resultados de eficiência em ambos os sistemas se deram a 800 W m-2, sendo 4,69% para o amorfo e 7,75% no policristalino. No entanto o primeiro apresentou menor queda de tensão com o aumento de temperatura. Obteve-se no sistema policristalino maior vazão, eficiência global e menores custos específicos.
22

Malá fotovoltaická elektrárna na rodinném domě / Small photovoltaic power station

Cingel, Štefan January 2018 (has links)
This diploma thesis deals with the principle of photovoltaic phenomenon and the distribution of photovoltaic systems. It also informs the reader about the possibilities of using the "Green Savings" subsidy within the program "New Green Savings" of the Ministry of the Environment. Last, but not least, it maps the energetic demands of the family house and, on the basis of it, presents the possible design of the photovoltaic system, including the estimation of the economic return.
23

Proposal of an Eco-Industrial Park based on the water desalination plant located inside the King Abdullah University of Science and Technology

Lopez Torres, Rodrigo 12 1900 (has links)
This thesis project is a proposal of a scenario of an industrial collaboration that could become the basis for the development of an Eco-Industrial Park inside the King Abdullah University of Science and Technology using the water desalination plant as the foundation of this network. It is defined why the university is a suitable place for a development of this type; what industrial networks can be formed and what environmental, economic and social benefits could be achieved if the Kingdom of Saudi Arabia implemented this project around the country. An Eco-Industrial Park is a collaboration between industries where they share resources and create an exchange network of wastes and by-products with the objective of obtaining positive environmental, economic and social impacts. In the proposed scenario, the initial collaboration is between a PV solar plant and the water desalination located inside the university. With the use of solar energy there are savings of CO2 emissions, which turn into positive impacts on the environment. The idea is that this initial collaboration could be extended in the future to provide the entire energy consumption of the KAUST community. The project also provides an insight into how an industrial symbiosis could be formed taking as a base this industrial collaboration. However, further studies and analysis are required in order to provide more solid information regarding the development of an Eco-Industrial Park.
24

Fotovoltaický systém pro RAPS aplikace / Photovoltaic system for RAPS applications

Nevoral, Miroslav January 2011 (has links)
The beginning of this work presents the basic principles of photovoltaic cells, their advantages and disadvantages. There is also an overview of photovoltaic systems. The next part takes a closer look on lead-acid accumulators followed by a practical part regarding the measurement of VA characteristics. The main goal of this work is to assemble an experimental PV system. It will consist of a PV module, an accumulator (consisting of two cells connected in series and producing an overall voltage of 5V) and of a variable load (assembled from nineteen resistors with resistance varying from tens to hundreds of Ohms). This system is connected to a computer that runs the control software which was created using the VEEPro 8.0 simulation environment. The measurements can be taken in two ways. Either the operator can select the load resistor combinations manually, or the operator only launches the measurement and the load is selected automatically by the software. This way we obtain an automatized workplace for measuring VA characteristics of photovoltaic panels.
25

Optimalizace návrhu velikosti PV systémů / Optimization proposal of size of PV systems

Vrzal, Martin January 2016 (has links)
The master thesis deals with proposal of size optimization of PV systems. According to results of optimization, alternative solutions of photovoltaic system were proposed for family house. From the perspective of costs efficiency were compared investment costs and savings of implementation of electricity supply directly to private consumption. Particularly for each of the proposed solution, profitability assessment of comparing purchasing costs and returns on investment was performed. Theoretical part of the master thesis consists of introduction into solar radiation principles, structure and functionality of photovoltaic systems, electronics inverters and accumulation of electric energy. The practical part is focused on measuring of electricity consumption in particular family house, calculation of sunlight intensity hitting tested house, making various solutions of photovoltaic power plants placed on the family house in order to evaluate returns on investments. In conclusion are summarized all results of investigated solutions according to economics aspects.
26

Control and Interface Design for Cost Reduction of a Low Power Grid-Connected Wind-Photovoltaic System

Musunuri, Shravana Kumar 30 April 2011 (has links)
The ever increasing demand for electricity has driven society toward the installation of new generation facilities. Concerns such as high costs associated with installation of new facilities, environmental pollution, higher transmission and distribution losses, depleting fossil fuels has created a lot of interest in exploring the renewable energy sources for generation, particularly near the load sites. Accordingly, emphasis has been put on Wind, and Photovoltaic (PV) energy systems. A study on the operational characteristics of these systems reveals that the power generation is high at certain optimal points and recognizing these optimum points and operating the system accordingly is an interesting and important part of the system design. Further, a hybrid Wind- PV system has higher reliability and generation capability when compared to either source alone, and as a result many such hybrid systems with an additional energy storage backup for increased reliability have been proposed. While the systems with energy storage are reported to have satisfactory performance, the energy storage component is typically found to incur the highest cost, requiring frequent maintenance and hence acts as a deterrent for increasing the renewable energy generation. Particularly, for small grid connected applications like shopping malls, office buildings, etc. any additional power that could not be provided by the hybrid system could be provided by the grid, and in case the power generation is higher it could be sent to the grid. For cases like this, it would be ideal if systems could be developed without energy storage, and maximum possible power could be extracted from the hybrid energy sources. Also, the power quality concerns posed due to the random nature of the power generated from the hybrid system, is an important issue that must be addressed. The conventional control methods used typically require overly sized component ratings, resulting in the degradation of the dynamic performance while adding to the cost of the system. This dissertation addresses these issues by proposing faster maximum power extraction algorithms from the hybrid renewable energy system, and proposes new control architecture for improving the output power quality to the grid.
27

Quasi Z-Source-Based Multilevel Inverter For Single Phase Photo Voltaic Applications

Gorgani, Aida, Gorgani January 2016 (has links)
No description available.
28

Avaliação de um sistema de bombeamento de água alimentado por painéis fotovoltaicos / Evaluation of a water pumping system fed by photovoltaic panels

Michels, Roger Nabeyama 06 June 2007 (has links)
Made available in DSpace on 2017-05-12T14:46:59Z (GMT). No. of bitstreams: 1 Roger Nabeyama Michels.pdf: 4361240 bytes, checksum: 896b2cd719d7885b070fecc71373f7e7 (MD5) Previous issue date: 2007-06-06 / The current dissertation describes an experiment to evaluate a water pumping system activated by two photovoltaic panels installed at The Federal Technological University of Paraná FTUPR, Medianeira Campus, in the State of Paraná, Brazil. The city of Medianeira s latitude and longitude are 25º17 43 south and 54º03 38 west respectively, with an altitude of 500.7 meters (1,642.72 feet). The system operated in a real working situation, pumping water to a 20 meters (65.62 feet) elevation. Data were collected, from February 2005 to November 2005, by means of a computerized data collector made by Campbell Scientific Inc that made possible collecting and applying irradiance values in the panel plane, generated current and tension, panel temperature, pressure and consume. Data readings were made at a 1-hertz frequency and stored every minute. Through calculi, the system efficiency and energy values and hydraulic strength were obtained. Winter solstice showed 9.58% efficiency with daily pumping of 2,056.44 liters (543.14 gallons) whereas summer solstice confirmed 9.07% efficiency with daily pumping of 2,377.21 liters (627.86 gallons). Winter day s highest efficiency is associated to the lowest temperature in those days compared to summer days, and the factor that prompted larger pumped water consume, during summer days, was related to solar insulation time that is longer if compared to winter days. Total water pumped during the experiment period was 435,042.20 liters (114,900.99 Gallons). / A presente dissertação descreve o experimento desenvolvido com a finalidade de avaliar um sistema de bombeamento de água acionado por dois painéis fotovoltaicos instalado nas dependências da Universidade Tecnológica Federal do Paraná UTFPR, Campus Medianeira, estado do Paraná, Brasil. O município está localizado no oeste paranaense com 25º17 43 Latitude sul, 54º03 38 Longitude oeste e com altitude de 500,7 metros. O sistema trabalhou em situação real de funcionamento, bombeando água a uma altura de 20 metros. Foram coletados dados de fevereiro de 2005 a novembro de 2005; utilizou-se um coletor de dados computadorizado da marca Campbell Scientific INC., o que possibilitou adquirir e armazenar os valores de irradiância no plano do painel, tensão e corrente gerada, temperatura no painel, pressão e vazão. A leitura dos dados foi realizada com freqüência de 1 hertz e armazenada a cada 1 minuto. Através de cálculos obtiveram-se os valores de potência e eficiência do sistema e a potência hidráulica. O solstício de inverno apresentou eficiência de 9,58% com bombeamento diário de 2.056,44 litros, enquanto que o solstício de verão apresentou eficiência de 9,07% com bombeamento diário de 2.377,21 litros. A maior eficiência nos dias de inverno está atrelada às menores temperaturas nestes dias se comparado aos dias de verão e o fator que provocou uma maior vazão de água bombeada nos dias de verão está ligado ao tempo de insolação solar que é maior se comparado aos dias de inverno. O total de água bombeada durante o período do experimento foi de 435.042,20 litros.
29

Análise comparativa de controladores MPPT aplicados a um sistema fotovoltaico / Comparative analysis of MPPT controllers applied to a photovoltaic system

Confessor, Sâmya Lorena de Medeiros 20 November 2014 (has links)
Made available in DSpace on 2016-08-31T13:33:41Z (GMT). No. of bitstreams: 1 SamyaLMC_DISSERT.pdf: 2613687 bytes, checksum: 971b2c2364adeaf29f31a7eed101a113 (MD5) Previous issue date: 2014-11-20 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The use of solar panels to generate electricity is something that is becoming more common comes in both large systems, as in autonomous systems with low power consumption. So that there is maximum utilization of energy generated, the panel must always operate at maximum power point (MPP). Based on this, this paper aim to perform a comparative study of two techniques for tracking the maximum power point MPPT (Maximum Power Point Tracking): the traditional method Perturbation and Observation (P&O) and the method by Fuzzy Logic. The photovoltaic system was modeled in ATLAB/Simulink® to represent the VI characteristic curve of the PV module, which is based on data available in the catalogs of commercial photovoltaic panels. From the results of the simulation study comparing control techniques, which showed that the fuzzy controller using the best performance and efficiency in keeping the MPP than the control technique based on the P&O was done / A utilização de painéis solares fotovoltaicos na geração de energia elétrica é algo que está se tornando cada vem mais comum, tanto em sistemas de grande porte, quanto em sistemas autônomos de baixo consumo de energia. Neste sentido, objetivando o máximo aproveitamento da energia gerada, o painel deve operar sempre no ponto de máxima potência(MPP). O presente trabalho têm como objetivo realizar um estudo comparativo entre duas técnicas de rastreamento do ponto de máxima potência MPPT (Maximum Power Point Tracking): o método tradicional Perturbação e Observação (P&O) e o método através da Lógica Fuzzy. O sistema fotovoltaico foi modelado no MATLAB/Simulink® de forma a representar a curva característica V-I do módulo PV, o qual baseia-se nos dados disponíveis nos catálogos de painéis fotovoltaicos comerciais. A partir dos resultados da simulação foi feito o estudo comparativo entre as técnicas de controle, que permitiram concluir que o controlador utilizando Fuzzy apresentou melhor desempenho e eficiência em se manter no MPP do que o controle baseado na técnica P&O
30

Desenvolvimento de um sistema de posicionamento automático para painéis fotovoltaicos

Alves, Alceu Ferreira [UNESP] 01 December 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:36Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-12-01Bitstream added on 2014-06-13T20:22:32Z : No. of bitstreams: 1 alves_af_dr_botfca.pdf: 3009487 bytes, checksum: 7d842f6597ccf4cbd7f7ebb8d5925852 (MD5) / A necessidade de oferecer alternativas para energização de propriedades rurais de pequeno porte com eficiência, confiabilidade e custo acessível, motivou a realização desta pesquisa, cujo enfoque principal foram os sistemas fotovoltaicos e a busca por um melhor desempenho destes sistemas a partir de estratégias de posicionamento dos painéis solares em direção ao Sol. Este trabalho apresenta o desenvolvimento experimental de um conjunto posicionador automático para módulos fotovoltaicos e a avaliação do funcionamento deste conjunto considerando-se o aumento na geração de energia elétrica em função da complexidade de implementação e do consumo de energia pelo próprio sistema de movimentação, além de seus custos de implantação. Foi projetado e implementado um dispositivo eletromecânico simplificado, capaz de sustentar e movimentar um módulo fotovoltaico ao longo do dia e ao longo do ano, sempre mantendo sua superfície direcionada em posição perpendicular aos raios solares incidentes. Utilizaram-se motores de passo, controlador lógico programável e componentes de baixo custo, que resultaram em um conjunto de manutenção simplificada,sem uso de sensores e com otimização dos movimentos, devido ao ajuste de inclinação do painel ser realizado somente uma vez ao dia. A avaliação do ganho na geração de energia elétrica baseou-se na coleta dos dados elétricos (tensão e corrente) e ambientais (insolação e temperatura) de dois sistemas fotovoltaicos com as mesmas características, instalados lado a lado, sujeitos às mesmas condições de insolação, temperatura e carga elétrica, sendo um fixo e outro móvel. A partir dos resultados obtidos concluiu-se pela viabilidade da proposta, não apenas pelo êxito no aumento da geração de energia, mas também pela boa relação custo/benefício, indicando que o sistema posicionador desenvolvido mostra-se vantajoso... / The need to offer alternatives of electricity supply to the small rural properties, providing them with efficiency, reliability and accessible cost, has motivated the development of this research, whose main approach was photovoltaic systems and the search for better performance of these systems with the solar panels positioning toward the sun. This work presents the experimental development of an automatic positioning system for photovoltaic modules and the evaluation of this system’s behavior taking in account the increase in generation of electric energy as a function of the complexity of implementation and the consumption of energy by the movement system itself, and its costs of implantation also. It was designed and built a simplified electromechanical device, which is able to support and to move a photovoltaic module along the day and along the year, always keeping its surface aimed to the sun rays. Stepper motors, programmable logic controller and low cost components were used, and these have resulted on a simplified maintenance set, with no sensors and optimization of movements, due the adjustment of panel’s inclination take place only once a day. The methodology adopted to evaluate the gain in the electricity generation was based on the acquisition of electrical data (voltage and current) and environmental data (insolation and temperature) from two photovoltaic systems whose have identical physical and electrical characteristics and were installed side by side, submitted to the same conditions of insolation, temperature and electric load. One of the solar panels was mounted on a fixed mechanical structure, and the other one on a mobile structure.The obtained results demonstrate the feasibility of the proposed mobile system, not only because of the real increase observed in electric energy generation, but also by the excellent cost effectiveness obtained... (Complete abstract click electronic access below)

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