Desenvolvimento de uma célula aplicada à geração de descargas parciais a partir de uma fonte de baixa tensão (original) (raw)
Related papers
2013
Large scale integration of Distributed Energy Resources, namely Distributed Generation at the Low Voltage level (LV), poses several technical challenges for distribution network operation in order to guarantee quality and interruptible service to the consumers. Especially the voltage profiles are affected by the high dispersed production. This paper presents a new application of electrical energy storage systems, demand side response (DSR) and microgeneration shedding, operating in a coordinated way to enable voltage control within LV distribution networks. A management tool developed in MATLAB ® allows to maximizing the integration of microgeneration , fulfilling the technical limits on the networks as well as ensuring the balance between production and consumption. Furthermore, the concept of smartgrid is an alternative to the current model for the LV distribution networks, allowing an integration of the distributed energy resources with increased flexibility in operation with the use of advanced control systems. This work applies a methodology for managing resources for voltage control, in the context of the smartgrid, to a real Portuguese LV distribution network. The methodology considers the control tool as one functionality of the Distribution Management System (DMS). Thus, for the application is essential to equip the network with control architectures that enable the management of different distributed energy resources. The models here developed should suit the real context, considering real scenarios, with loads, production profiles and technical operation conditions, with the fulfillment of all constraints associated with the technical limits of the LV distribution networks. The application of the models developed in this paper to the LV distribution networks is essential for validation with a practical application in the near future. In conclusion, the contribution of the work within this dissertation provides the operator with new models and management tools for the control of LV distribution networks. The application of this tool in a real LV network secured the control of the voltage profiles in all its buses for the considered time period, ensuring the balance between production and consumption and maximizing the integration of distributed energy sources, in particular based on renewable resources. vi vii Agradecimentos Um agradecimento especial ao Dr. André Guimarães Madureira, investigador sénior no Instituto de Engenharia de Sistemas e Computadores do Porto (INESC Porto), pela dedicação, orientação, acompanhamento, a boa disposição e empatia com qual me recebeu. Por fim, um agradecimento aos meus pais e à minha irmã por todo o apoio ao longo destes meses de trabalho.
Construção de uma célula de gás de baixo custo para análise no infravermelho
Química Nova, 2011
Recebido em 11/6/10; aceito em 13/11/10; publicado na web em 18/2/11 CONSTRUCTION LOW-COST GAS CELL FOR INFRARED ANALYSES. Infrared spectroscopy is a versatile technique used for qualitative and quantitative determination of all types of molecular species. As far as analysis of confined or flowing gases is concerned, different types of cell can be found in the market, but they are often very expensive. This study describes the construction of a very efficient gas cell with good reproducibility for qualitative infrared analysis of confined or flowing gases, using easily available and low-cost materials.
2020
This present scientific work refers to the development of the project of an adjustable voltage source with a range of up to 30 Volts (V) and 5 Amps (A). Which operates based on a buffer circuit, this system being microcontrolled in order to allow both manual and digital parameter adjustment, through a graphical interface. Such interface allows to adjust the operating voltage, the maximum current of the source and to receive the actual reading of these values. In addition, this project observes different modes of protection, in this sense, the output is disabled in the event of a current higher than the established maximum or a high internal temperature than can cause the system to suffer damage. However, it seeks to maintain a low value of the project so that it is accessible, taking into account the need for this instrument in teaching related to electrical or electronic engineering. In order to offer a solution to the lack of this instrument in the context of teaching electronic circuits.
Fonte de Alimentação de Baixa Tensão e Elevada Corrente para Microprocessadores
2013
This thesis entitled "Low-voltage and High-Current Power Supply for Microprocessors"focuses on the context of supply the new Microprocessors, which are increasingly being developed because of their capability and speed processing. One of the big issues in the evolution of these microprocessors is its own supply. This thesis discusses the essential blocks needed to implement a voltage source regulator, responsible for the supply of these microprocessors. For this, it begins by addressing the topologies used for this type of converters as well as the methods to control them. Then the choice is made from the available topologies and control methods. After this is done the design of passive and active elements of the converter and the simulation of them in open loop and closed loop. Finally, presents the implementation of this converter, which appears only in open loop control. This converter has the following main specifications: input voltage, V in = 5V , output voltage, V out = 1.5V , maximum variation of the load, ∆I = 50A, switching frequency, f s = 200kHz and with four phases. As a final balance, in general, satisfactory results were observed both in simulation and in the experimental part. v vi Agradecimentos Para a realização desta dissertação, foi necessária a colaboração, atenção e apoio de algumas pessoas, a quem gostaria de expressar a minha profunda gratidão. Agradeço ao Professor Doutor António José Pina Martins pela sua orientação, conselhos, constante exigência e apoio manifestado em todas as fases do trabalho. Agradeço à minha família pelo apoio e incentivo constante dado ao longo do trabalho. Finalmente, uma palavra também para os meus amigos, que de uma forma ou de outra contribuíram, com sugestões, comentários ou simplesmente pelo apoio moral. Ruben Tiago Pinto Sarmento da Costa vii viii "O mais alto de nós não é mais que um conhecedor mais próximo do oco e do incerto de tudo."
Avaliação de métodos para detecção de descargas parciais em transformadores
VI Simpósio Brasileiro de Sistemas Elétricos, 2022
In this paper, several methods for detecting partial discharges in transformers will be discussed. The occurrence of partial discharges in electrical equipment is of great concern to energy companies, as they are defects that are often not noticeable during a visual inspection. This causes the partial discharge to evolve into a more severe defect, often causing the need to remove equipment from service. The different methods for detecting partial discharges will be discussed and their characteristics and applicability will be investigated. In addition, the main advantages and disadvantages of each method will be presented. Resumo: Neste artigo diversos métodos para detecção de descargas parciais em transformadores serão abordados. A ocorrência de descargas parciais em equipamentos elétricos é de grande preocupação para empresas de energia, pois são defeitos que muitas vezes não são perceptíveis durante uma inspeção visual. Isso faz com que a descarga parcial evolua para um defeito mais severo, muitas vezes causando a necessidade de remover o equipamento de serviço. Os diferentes métodos para detecção de descargas parciais serão abordados e terão suas características e aplicabilidade investigados. Além disso, serão apresentadas as principais vantagens e desvantagens de cada método.
Impactos da geração distribuída nas redes de baixa tensão
2012
Diante da crescente demanda por energia, e considerando que sao cada vez maiores as exigencias financeiras e ambientais para implantacao de grandes empreendimentos de geracao, a geracao conectada as redes de distribuicao e proximas aos centros de consumo se apresentam como uma alternativa para o suprimento dessa demanda. Essa geracao e denominada Geracao Distribuida GD e tem como principal vantagem a reducao do transporte de energia dos centros de geracao que, na sua grande maioria, sao distantes dos centros de consumo. Do exposto acima, e gracas a movimentacao do setor industrial, o governo brasileiro atraves da ANEEL Agencia Nacional de Energia Eletrica regulamentou, por meio da resolucao 482/2012, a conexao dos empreendimentos de GD as redes de distribuicao de energia. A insercao dessas fontes de geracao distribuida representa um grande desafio, pois trata-se de uma mudanca de paradigma para as distribuidoras, uma vez que altera significativamente o seu planejamento, operacao e m...