• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 2
  • Tagged with
  • 2
  • 2
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 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.
1

Uma an??lise da din??mica do setor el??trico brasileiro utilizando VAR em painel

Brand??o, Lucas Guimar??es Lins 06 March 2017 (has links)
Submitted by Sara Ribeiro (sara.ribeiro@ucb.br) on 2017-06-12T13:18:37Z No. of bitstreams: 1 LucasGuimaraesLinsBrandaoDissertacao2017.pdf: 2537420 bytes, checksum: b4b5f382d28719b591da3a8cecc26002 (MD5) / Approved for entry into archive by Sara Ribeiro (sara.ribeiro@ucb.br) on 2017-06-12T13:18:44Z (GMT) No. of bitstreams: 1 LucasGuimaraesLinsBrandaoDissertacao2017.pdf: 2537420 bytes, checksum: b4b5f382d28719b591da3a8cecc26002 (MD5) / Made available in DSpace on 2017-06-12T13:18:44Z (GMT). No. of bitstreams: 1 LucasGuimaraesLinsBrandaoDissertacao2017.pdf: 2537420 bytes, checksum: b4b5f382d28719b591da3a8cecc26002 (MD5) Previous issue date: 2017-03-06 / This study estimates the interrelation between selected variables of the Brazilian electric sector and the Brazilian economy. Using monthly data from the submarkets (Southeast / Center-West, South, Northeast and North) and the Brazilian economy, these qualify these relationships through the panel vector autoregression (PVAR) methodology and impulse response. This method has the quality to evaluate the response of the several variables to the disturbances, without giving focus to a mathematical modeling. It is identified that the Brazilian energy market has a rigidity of the distributors' energy tariff, which can be explained by the state's regulatory intervention. Futhermore there is a relationship between consumption and energy tariff, however, this is not directly related to the short-term market price. / Esta disserta????o tem o objetivo de avaliar a inter-rela????o entre vari??veis selecionadas do setor el??trico brasileiro e da economia. Utilizando dados mensais em painel dos submercados (Sudeste/Centro-Oeste, Sul, Nordeste e Norte) e da economia brasileira, de forma qualificar essas rela????es por meio da metodologia de vari??vel autorregressiva em painel (PVAR) e de impulso resposta. Este m??todo possui a qualidade de avaliar a resposta das diversas vari??veis a dist??rbios, sem dar foco ?? uma modelagem matem??tica. Identifica-se que o mercado de energia el??trica brasileiro possui uma rigidez da tarifa de energia el??trica das distribuidoras, que pode ser explicada pela interven????o regulat??ria do Estado. E que existe uma rela????o entre consumo e tarifa m??dia de energia el??trica, no entanto, esta n??o est?? diretamente relacionada ao pre??o do mercado de curto prazo.
2

Localiza??o de faltas em linhas de transmiss?o usando morfologia matem?tica / Location of Fault Lines Transmission using Mathematical Morphology

Cavalcante, Paulo Anderson Holanda 19 April 2011 (has links)
Made available in DSpace on 2015-03-03T15:07:33Z (GMT). No. of bitstreams: 1 PauloAHC_DISSERT.pdf: 3758465 bytes, checksum: 6b6aaaf4f22bae19573b264eb2e88629 (MD5) Previous issue date: 2011-04-19 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This work an algorithm for fault location is proposed. It contains the following functions: fault detection, fault classification and fault location. Mathematical Morphology is used to process currents obtained in the monitored terminals. Unlike Fourier and Wavelet transforms that are usually applied to fault location, the Mathematical Morphology is a non-linear operation that uses only basic operation (sum, subtraction, maximum and minimum). Thus, Mathematical Morphology is computationally very efficient. For detection and classification functions, the Morphological Wavelet was used. On fault location module the Multiresolution Morphological Gradient was used to detect the traveling waves and their polarities. Hence, recorded the arrival in the two first traveling waves incident at the measured terminal and knowing the velocity of propagation, pinpoint the fault location can be estimated. The algorithm was applied in a 440 kV power transmission system, simulated on ATP. Several fault conditions where studied and the following parameters were evaluated: fault location, fault type, fault resistance, fault inception angle, noise level and sampling rate. The results show that the application of Mathematical Morphology in faults location is very promising / Neste trabalho, um algoritmo de localiza??o de faltas ? desenvolvido, consistindo dos m?dulos de detec??o, classi ca??o e localiza??o da falta. Na implementa??o do algoritmo a Morfologia Matem?tica ser? a ferramenta utilizada para analisar os sinais das correntes obtidas em um dos terminais da linha. Diferente das Transformadas de Fourier e Wavelet que s?o normalmente aplicadas ? localiza??o de faltas, a Morfologia Matem?tica ? uma transforma??o n?o linear baseada apenas em opera??es de adi??o e subtra??o acompanhadas da extra??o de m?ximos e m?nimos de conjuntos discretos. Portanto, a Morfologia Matem?tica apresenta a vantagem de ser computacionalmente bastante e ciente. Nos m?dulos de detec??o e classi ca??o a Wavelet Morfol?gica foi usada na extra??o de informa??es contidas nas baixas e nas altas frequ?ncias. No m?dulo de localiza??o da falta o ltro Gradiente Morfol?gico Multirresolu??o foi utilizado na detec??o dos instantes de chegada das ondas viajantes e na determina??o de suas polaridades. A partir dos instantes de chegada das duas primeiras ondas viajantes incidentes no terminal de medi??o e da velocidade de propaga??o dessas ondas, a localiza??o da falta pode ser estimada com precis?o. Para analisar o desempenho do algoritmo, um sistema de transmiss?o de 440 kV simulado no software ATP foi submetido ? diversas circunst?ncias de falta, variandose par?metros como: dist?ncia da falta, tipo da falta, resist?ncia da falta, ?ngulo de incid?ncia da falta, n?vel de ru?dos e frequ?ncia de amostragem dos sinais. Os resultados obtidos mostram que a aplica??o da Morfologia Matem?tica na localiza??o de faltas ? bastante promissora

Page generated in 0.2832 seconds