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Método de sincronização aplicado a conversores PWM trifásicos
(Universidade Federal de Santa Maria, 2006-07-17)
In the last decade, disturbances in the electrical system have been increased, mainly due to proliferation of nonlinear loads. As a result harmonic distortion, voltage unbalance and frequency variations are becoming a ...
Desenvolvimento e implementação de uma micro-rede avançada de alta freqüência para integração de fontes alternativas de energia
(Universidade Federal de Santa Maria, 2006-03-17)
This Thesis presents a distributed generation system, which works as a Microgrid, suitable to integrate alternative energy sources, using a high frequency AC link (HFAC) as a means of connecting sources and loads. The ...
Contribuição ao estudo da máquina assíncrona trifásica duplamente alimentada aplicada a aerogeradores de velocidade variável
(Universidade Federal de Santa Maria, 2006-07-28)
This work presents the analysis and implementation of a vector control applied to Doubly-Fed Induction Generators (DFIG) used in grid connected wind turbines. DFIG s are
nowadays the more widely used concept for grid ...
Sistema para aproveitamento de energia vibracional baseados em transdutores acústicos piezelétricos de baixo custo
(Universidade Federal de Santa Maria, 2006-03-08)
This dissertation presents the development of a system for converting the mechanical energy from vibrations into electrical energy. The conversion is performed in a low-cost piezoelectric transducer, commonly known as ...
Novos métodos para reconfiguração das redes de distribuição a partir de algoritmos de tomadas de decisão multicriteriais
(Universidade Federal de Santa Maria, 2007-12-14)
The electric networks reconfiguration has as purpose: to reduce the energy losses, to improve the voltage profile for the customers, to increase the reliability levels or to re-establish the energy supply in contingency ...
Metodologia para a análise dos efeitos da geração distribuída sobre as características operacionais dos sistemas de distribuição utilizando técnicas multicriteriais
(Universidade Federal de Santa Maria, 2007-11-08)
Nowadays, the Brazilian electric systems need the development of new researches and tools, in order to obtain a logic solution to maintain and improve the reliability and the quality of the power delivered to customers. ...
Metodologia de projeto de conversores boost para correção de fator de potência apliocada a sistemas ininterruptos de energia
(Universidade Federal de Santa Maria, 2006-04-20)
This Master Thesis presents a design methodology to a boost PFC converter operating as an Uninterruptible Power Supply rectifier input stage. This methodology defines, making use of a group of current ripples and switching ...
Uma contribuição ao controle de motores de indução trifásicos sem o uso de sensores mecânicos
(Universidade Federal de Santa Maria, 2007-06-01)
This work presents contributions to encoderless speed servo study using three phase induction motor. Initially, a general overview on the literature is presented about control
techniques applied to encoderless speed servo ...
Contribuições ao estudo de conexão de geração eólica à rede elétrica
(Universidade Federal de Santa Maria, 2007-08-24)
Distribution systems have not been designed to receive distributed generation (DG) units. The electric energy injection in these systems is safe and reliable if the characteristics regarding of DG interconnection in ...
Desenvolvimento de conversores estáticos para sistemas fotovoltaicos autônomos
(Universidade Federal de Santa Maria, 2007-07-12)
This work presents a new energy conditioning system for application in stand-alone photovoltaic systems with battery bank. Firstly, the characteristics of solar photovoltaic energy, the modeling of a photovoltaic cell and ...