Current Transformer
Mostrando 1-12 de 25 artigos, teses e dissertações.
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1. A 50Ω Microstrip Line Fed Shorted Hexagonal Microstrip Antennas with Reduced Cross-Polarization
Abstract A Hexagonal Microstrip Antenna (HMSA) is an approximation to a Circular MSA (CMSA), which is not symmetrical over two principal planes, unlike a CMSA. Consequently, two types of feed positions are feasible for each X and Y-axes. When a quarter-wave transformer or inset feed is used to match the edge impedance of the HMSA, it becomes asymmetrical ove
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 19/06/2019
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2. Effect of Spun Velocities and Composition on the R‒phase and Thermomechanical Behavior in Ti‒Ni Ribbons Electrically Heated
This work deals with structural, electrical and mechanical characterization of Ti‒50.13Ni and Ti‒49.62Ni (at.%) shape memory alloys (SMAs) fabricated at different circumferential wheel velocities. The effect of wheel velocity, chemical composition and heat treatments are investigated. The characterization of crystallographic phases of the Ti‒Ni ribbons
Mat. Res.. Publicado em: 08/04/2016
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3. DEVELOPMENT OF INSULATING MAGNETIC OIL FOR TRANSFORMERS
The Centrais Elétricas do Norte do Brasil AS – Eletronorte, as well as other companies in the world energy sector, have problems of loss of the performance by excessive heat and even accidents with their transformers. The maintenance and accidents impact of energy supply, generating profit and more expensive insurance premiums. The transformers are essent
Publicado em: 20/07/2014
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4. A systematic sensitivity analysis of the performance of a transcutaneous energy transmitter for design purposes
This work studies a Transcutaneous Energy Transmitter (TET) which uses electromagnetic fields to transfer power from outside the body to an artificial organ in the body, working like a high frequency transformer with the skin being part of the magnetic coupling between the primary (external coil) and secondary (internal coil). For this reason, this project m
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2013-12
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5. Algoritmo híbrido e inteligente para o diagnóstico das condições operativas de transformadores de potência no contexto da qualidade da energia elétrica / Hybrid intelligent algorithm for the diagnosis of operating conditions of power transformers in the context of power quality
This research aimed to develop an algorithm able to diagnose the operating conditions of power transformers. The variables considered to classify the presented conditions were the normally used by differential protection logic, i.e., the differential current and the harmonic content in the signals in analysis. Moreover, the relationship between some phenomen
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 12/07/2012
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6. Projeto diferencial de geradores síncronos: o uso de redes neurais artificiais para identificação e correção da saturação dos transformadores de corrente / Differential protection for synchronous generators: the use of artificial neural networks for identification and correction of the saturation of current transformers.
Este trabalho tem como objetivo apresentar um algoritmo de proteção diferencial de geradores baseado em Redes Neurais Artificiais (RNAs), que seja robusto e confiável em situações onde os algoritmos padrões podem apresentar dificuldades, como no caso, da saturação de TCs. O algoritmo desenvolvido é constituído por dois módulos principais: a) um m�
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 09/03/2012
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7. Uma contribuição ao estudo de limitadores de corrente elétrica supercondutores usando transformador e fita supercondutora de alta temperatura crítica / A contribution to the study of superconductive fault current limiters using transformer and high critical temperature superconductive tape
Esta dissertação apresenta um estudo sobre limitadores de corrente elétrica supercondutores que funcionam com um transformador e com material supercondutor de alta temperatura crítica (HTS) em forma de fita. Neste caso utilizou-se a fita supercondutora do composto de YBCO. Neste trabalho é apresentado um resumo da evolução da supercondutividade desde
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 03/03/2011
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8. MÉTODOS PARA CORREÇÃO DAS DISTORÇÕES DA FORMA DE ONDA SECUNDÁRIA CAUSADAS PELA SATURAÇÃO DE TRANSFORMADORES DE CORRENTE PARA SERVIÇO DE PROTEÇÃO / METHODS FOR CORRECTION OF SECONDARY WAVEFORM DISTORTIONS CAUSED BY SATURATION OF CURRENT TRANSFORMERS FOR PROTECTIVE RELAYING PURPOSES
This work aims to evaluate the performance of some methods used to detect and correct the distorted portions of the secondary current signal waveform, which occur due to the core saturation of current transformers. Such methods are presented didactically divided among techniques existing in the specialized literature and new methodologies proposed. Involving
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 18/02/2011
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9. Conversor CC/CA de alta freqüência baseado em inversores ressonantes com comutação seqüencial para excitação de uma tocha indutiva a plasma térmico
This work describes the study, the analysis, the project methodology and the constructive details of a high frequency DC/AC resonant series converter using sequential commutation techniques for the excitation of an inductive coupled thermal plasma torch. The aim of this thesis is to show the new modulation technique potentialities and to present a technologi
Publicado em: 2010
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10. Single-line-to-earth fault limitation through the setting of Petersen coil in power transformer neutral / Limitação de correntes de falta fase-terra por meio do ajuste de bobina de petersen em neutro de transformadores de potência
The Petersen coil insertion on the neutral of the electrical distribution power system transformers has been a technical strategy adopted for several electrical utilities, in many countries with the purpose to reduce the earth-fault current intensities, enabling circuit disconnect decrease for intermittent faults and so to improve the electrical power qualit
Publicado em: 2009
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11. Inversor monofásico sincronizado para a conexão de um gerador eólico à rede elétrica : estudo, projeto e implementação
The aims of this work are the study, design and implementation of a dc/ac converter for the connection of a wind power generator to the electric grid. It makes use of a single-phase inverter, with three-level PWM modulation, connected to the grid through a low frequency transformer. Three distinct variables are controlled in the converter: the output current
Publicado em: 2009
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12. Nursing university faculty and the Burnout Syndrome: a health education issue / O docente universitário em Enfermagem e a Síndrome de Burnout: uma questão de educação para a saúde
The complex demands directed to the university faculty in terms of the exigencies of accomplishing teaching, research, and extension/assistance tasks, as well as administrative activities eventually make the professional fall ill due to excessive attributions. Objectives: 1) Survey the faculty of a state nursing college about the meaning they assign to their
Publicado em: 2008