Compensators
Mostrando 1-12 de 23 artigos, teses e dissertações.
-
1. Estabilidade e estabilização de uma classe de sistemas não-lineares sujeitos a saturação
This work addresses the problem of stability analysis and stabilization of nonlinear rational systems subject to saturation. The approach used in this study is based on the differential algebraic representation (DAR) of rational systems and on a modified version of the generalized sector condition to deal with saturation. First, methods to characterize the s
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 2012
-
2. Compensadores série de tensão em onda quadrada: aplicação na mitigação de afundamentos de tensão
Series voltage compensators (SVC) have become the main solution to protect electrical loads against voltage sags in recently years. Researchers have developed new technologies that aimed the reduction of the SVC size, in terms of power and voltage, and also cost. In order to achieve this purpose, some simplifications have been made, such as the absence of se
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 28/09/2011
-
3. Analysis of signal processing techniques for optical 112 Gb/s DP-QPSK receivers with experimental data
This paper evaluates several signal processing techniques for optical dual-polarization quadrature phase-shift keying (DP-QPSK) coherent receivers, using offline post-processing of experimental data. In addition to electronically separating the two polarization multiplexed signals, the investigated signal processing algorithms also compensate for chromatic d
Journal of Microwaves, Optoelectronics and Electromagnetic Applications. Publicado em: 2011-06
-
4. Projeto de um sistema fotovoltaico autônomo de suprimento de energia usando técnica MPPT e controle digital
This work presents the design and development of a battery charger aiming at applications in autonomous photovoltaic systems of low energy consumption, using a Buck type converter with digital control for the loading process based on a digital signal processor TMS320F2812 from Texas Instruments. In order help dimensioning the converter components the photovo
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 28/08/2009
-
5. Control of integrating process with dead time using auto-tuning approach
A modification of Smith predictor for controlling higher order processes with integral action and long dead-time is proposed in this paper. The controller used in this Smith predictor is an Integral-Proportional Derivative controller, where the Integrator is in the forward path and the Proportional and Derivative control are in the feedback, acting on the fe
Brazilian Journal of Chemical Engineering. Publicado em: 2009-03
-
6. AVALIAÇÃO E REFORÇO DAS CONDIÇÕES DE ESTABILIDADE DE TENSÃO EM BARRAS DE TENSÃO CONTROLADA POR GERADORES E COMPENSADORES SÍNCRONOS / VOLTAGE STABILITY ASSESSMENT AND ENHANCEMENT IN VOLTAGE-CONTROLLED BUSES BY SYNCHRONOUS GENERATORS AND COMPENSATORS
After the incidence of some voltage collapses in the energy transmission systems in the world, the voltage security became an issue of great interest in the last years due to the importance of its impact. The phenomenon of voltage stability is due to the excessive active and reactive power flow in the electrical transmission network and has been associated w
Publicado em: 2009
-
7. Controle digital de inversores monofásicos com realimentação de estados internos
This work presents a contribution to the study of PWM sinusoidal inverters. It is presented some voltage output control techniques highlighting the advantages and disadvantages. One technique using two feedback loops and compensation by proportional integral compensators, besides showing a natural short circuit protection, is implemented and evaluated by stu
Publicado em: 2009
-
8. 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
-
9. Determinação dos parâmetros de compensadores estáticos de reativos e estratégia para o projeto otimizado de reatores saturados
Due to the increasing demand of consumption, the electric energy systems have faced, in the current times, problems with its operation, being the voltage control one of the most relevant matters. To provide means to solve such problems, the use of static compensators has emerged, amongst others, as a classical alternative. Although the modern solutions are m
Publicado em: 2008
-
10. Compensação de atrito em válvulas de controle. / Friction compensation in control valves.
Friction is a nonlinearity that generally produces bad performance of a mechanical system with moving parts. In this work, the studied mechanical element is the process control valve, which is the most used final control element in process industries. The presence of friction in control valves increases control loop variability, generating impact in all plan
Publicado em: 2008
-
11. A melhoria da disponibilidade do compensador estÃtico da SE FTZ/CHESF atravÃs da anÃlise da sua Ãrvore de falhas
In the Electrical Power Systems, the Static Compensators â CE are equipment of extreme importance for tension regulation, both in a permanent regime as in a transitory one, mainly in systems where the load centers are located at great distances of the generating plant. This dissertation presents an analysis of the fault causes in the Static Compensator inst
Publicado em: 2008
-
12. The optical absorption of gamma irradiated and heat-treated natural quartz
Quartz with aluminum as impurity absorbs energy from ionizing radiation and modifies its color. Colorless quartz becomes smoky or dark smoky (morion quartz) when exposed to gamma rays. By heat-treatment, smoky quartz may become successively greenish, yellowish, or brownish as the irradiation dose increases. Natural, colorless quartz is routinely colored by i
Materials Research. Publicado em: 2005-09