Switching Circuits
Mostrando 1-12 de 25 artigos, teses e dissertações.
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1. Análise do comportamento de uma linha de um pouco mais de meio comprimento de onda sob diferentes condições de operação em regime permanente e durante a manobra de energização / Analysis of the behavior of an isolated transmission line with a little more than half wave lenght for different operating conditions in steady state and during the energization manouver
This work presents an analysis of the behavior of an isolated transmission line with a little more than half-wave length (2600 km) on fundamental frequency, 60 Hz, connected to an infinite busbar for different operating conditions. The voltage and current profiles for different loading conditions are monitored along the line. An analysis of the influence of
Publicado em: 2010
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2. EXPLORAÇÃO DE OPERADORES ARITMÉTICOS NA TRANSFORMADA RÁPIDA DE FOURIER / ARITHMETICS OPERATORS EXPLORATION IN FAST FOURIER TRANSFORM
The power consumption reduction in the fast Fourier transform (FFT) is important because applications in battery-powered embedded systems grows daily. Thus this work focuses on the application of techniques to reduce power in specific projects of FFT algorithms. The goal is to achieve an architectural exploration in the FFT core, the decimation in time butte
Publicado em: 2010
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3. SYNTHESIS METHODOLOGY FOR SIMPLIFIED ZVT TOPOLOGIES APPLIED TO BIDIRECTIONAL PWM POLES / METODOLOGIA DE SÍNTESE DE TOPOLOGIAS ZVT SIMPLIFICADAS APLICADAS A PÓLOS PWM BIDIRECIONAIS
Among the soft-switching techniques, the zero-voltage-transition (ZVT) technique has been accepted well by the industry due its attractive characteristics, such as simplicity, low losses in the auxiliary commutation circuit (ACC), operation with soft-switching for a wide load range, and closest operation to the PWM converter counterpart. In three-phase volta
Publicado em: 2009
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4. Antenas e superfícies seletivas de freqüência reconfiguráveis para sistemas de comunicação sem fio
Este trabalho tem como objetivo apresentar como as antenas de microfita e as superfícies seletivas de frequência reconfiguráveis podem ser alternativas para operar em sistemas de comunicação sem fio que necessitem alterar sua frequência de operação de acordo com os requisitos impostos a este sistema ou condições do meio. O propósito central é apr
Publicado em: 2009
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5. CONTRIBUTION TO THE CONTROL OF ELECTRODYNAMIC VIBRATION MACHINES / CONTRIBUIÇÃO AO CONTROLE DE MÁQUINAS DE VIBRAÇÃO ELETRODINÂMICAS
This work presents contributions to the sinusoidal acceleration control of electrodynamic shakers applied in vibration testing. Considering the importance of sine tests to identify critical frequencies of operation and to determine mechanical weakness in the specified performance of specimens, vibration controllers are designed to reproduce the amplitude and
Publicado em: 2009
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6. Combinational digital circuit in multi-valued logic / Circuitos digitais combinacionais na lógica de múltiplos valores
The combinational digital circuits are designed in binary logic known as Switching Algebra, and depending of the complexity have limitations, some of them are consumption of energy and the size of the circuits generated by the number of interconnections, one alternative to solve this problem is the use of Multilevel Logic also known as Multi-valued Logic (MV
Publicado em: 2008
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7. Circuitos integrados de radio-recepção para a operação de multiplexação espacial de antenas em tempo real / Integrated circuits of radio-reception for spatial multiplexing of antennas in real time
This research aims the conception of new topologies of integrated circuits and its characterizations for operation in radio-receiver systems. The design and fabrication of RF switches, LNAs, mixer, and VCOs are presented. The SMILE - Spatial MultIplexing of Local Elements - technique was adopted due to its advantages and functionality for the intelligent ant
Publicado em: 2008
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8. INVERSORES ZCZVT COM ACOPLAMENTO MAGNÉTICO: SÍNTESE E ANÁLISE.
This Ph. D. Thesis presents a in deep study of the mechanism of resonant transition soft-switching techniques. By means of the principles that rules the PWM resonant transition converters, a novel tool for analysis and synthesis have been developed. This novel tool also permit to be verified some of the main factors that made possible to he ZVT technique to
Publicado em: 2008
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9. Medição de impedância utilizando sistemas digitais
Conducting measurements is, in the most part of practical situations, essential for scientific research. It is so important, that it can be said, that all areas in engineering are dependent of it. As well known, impedance measurement is a subject of great interest in many application fields, each of which has different demands in terms of accuracy, range, me
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 12/06/2007
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10. Projeto de um inversor trifásico com snubber de undeland regenerativo e controle digital implementado no DSP TMS320F2812
This work deals with the design and implementation of the digital instantaneous averaged values control for output voltages of the three-phase inverter with Underlands snubber, using the Buck-Boost converter for regeneration of the snubbers energy. The qualitative and quantitative analysis of the inverter power structure, snubber and auxiliary converter, as
Publicado em: 2007
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11. Sensitivity analysis of secondary arc current for different transmission lines / Analise de sensibilidade da corrente de arco secundario para diferentes linhas de transmissão
The secondary arc appears in single-phase switching during clearing of non-permanent ground single-phase to ground faults. The problem happens especially on EHV lines, on aerial isolation, in faults with non permanent characteristics. In this work different transmission lines with voltage levels of 345 kV up to 765 kV and with 150 km up to 900 km length are
Publicado em: 2007
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12. Duble forward converter with two main and auxiliary switches and soft switching / Conversor duplo Forward PWM a duas chaves principais e duas chaves auxiliares com comutação suave
Converting a constant voltage in another constant voltage is necessary in many technological applications, starting from charging a cell phone battery to feed a DC motor in industrial plants. This work presents one more way to convert a Constant voltage based on a new circuit topology. This topology has its embryo in the simplest step-down configuration, the
Publicado em: 2006