Uma metodologia de diagnóstico de distúrbios em sistemas de distribuição baseada nos sinais de corrente

With a growth in demand for electrical energy, it is noticed that the Brazilian power system tends to become more complex, as well as more susceptible to the occurrence of various types of failures. Disturbances that cause interruptions in the power supply, for example, are monitored daily through r...

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Detalles Bibliográficos
Autor: Chagas, Talita Santos Alves
Tipo de recurso: tesis de maestría
Estado:Versión publicada
Fecha de publicación:2020
País:Brasil
Institución:Universidade Federal de Sergipe (UFS)
Repositorio:Repositório Institucional da UFS
Idioma:portugués
OAI Identifier:oai:oai:ri.ufs.br:repo_01:riufs/16211
Acceso en línea:http://ri.ufs.br/jspui/handle/riufs/16211
Access Level:acceso abierto
Palabra clave:Engenharia elétrica
Transformada wavelet discreta
Análise multirresolução
Transformada de Fourier
Método dos mínimos quadrados
Wavelet Daubechies
Decomposição
Distúrbios de qualidade de energia
Faltas
Discrete wavelet transform
Multiresolution analysis
Fourier transform
Ordinary least squares
Daubechies wavelet
Decomposition
Power quality disturbances
Faults
ENGENHARIAS::ENGENHARIA ELETRICA
Descripción
Sumario:With a growth in demand for electrical energy, it is noticed that the Brazilian power system tends to become more complex, as well as more susceptible to the occurrence of various types of failures. Disturbances that cause interruptions in the power supply, for example, are monitored daily through regulations on energy distribution services. However, there is still a need to automate the distribution systems so their equipment, such as automatic reclosers, act swiftly, safely and effectively during the disturbance classification processes. With the information stemming from the identification and classification of disturbances, the electric power companies can act to minimize their frequency of occurrence. In order to achieve this objective, this work presents a set of methods able to classify certain disturbances and faults in the distribution system - short circuits, inrush current, connection of large loads, harmonic distortion, current unbalance and frequency variation - based only on the analysis of the behavior of current signal oscillographs. This classification occurs through the segmentation of the signals employing, mostly the discrete wavelet transform, via multiresolution analysis. Other techniques, such as the Fourier transform and the ordinary least squares, are used in the background in order to assist in some decisions. A database with 510 synthetic signals (simulated in a test system, parameterized with real data from a distribution system and built in the Alternative Transients Program software), and 41 real currents signals from short-circuit have been applied in order to validate the methods. The results indicate to feasibility of using the algorithm as a tool for classifying disturbances.