https://repositorio.ufpb.br/jspui/handle/123456789/13354 2026-04-15T11:26:43Z 2026-04-15T11:26:43Z Silva, Filype Anastácio Nascimento https://repositorio.ufpb.br/jspui/handle/123456789/13381 2019-02-12T06:03:06Z 2017-11-24T00:00:00Z

Título: Conversor CA-CC-CA Monofásico de Três Braços Conectado em Paralelo Aplicado ao Melhoramento da Qualidade de Energia João Pessoa Autor(es): Silva, Filype Anastácio Nascimento Orientador: Rocha, Nady Abstract: Power quality is a theme that has been widely discussed inside industrial and academic environments. In fact, it is one of the big challenges of modern engineering. Problems related to electric power quality have ... Editor: Universidade Federal da Paraíba Tipo: TCC

2017-11-24T00:00:00Z Siqueira, Luanna Maria Silva de https://repositorio.ufpb.br/jspui/handle/123456789/13359 2019-02-09T06:04:55Z 2017-11-24T00:00:00Z

Título: Sistema de Geração Eólica Baseado em um Gerador de Indução de Rotor Bobinado com Conversor Série no Lado da Rede Elétrica sem Transformador Autor(es): Siqueira, Luanna Maria Silva de Orientador: Rocha, Nady Abstract: This work presents the study of a system of wind generation connected to the electrical grid using Doubly Fed Induction Generator (DFIG). The proposed configuration presents the DFIG with the stator windings connected directly to the three-phase grid and connected to a serial converter, the rotor windings are fed by a AC-DC-AC converter. The series inverter is added to this topology in order to ensure a balanced three-phase sine-wave voltage to the generator terminals even if the grid voltage has some voltage sag. It is presented a comparison between the proposed and the conventional topology, which presents the use of transformer. For the development of this work, the model of the system, the model of the wind turbine and the dynamic model of the machine is presented as well. The Power Width Modulation (PWM) and control of the converters strategies are presented. Control of the reactive power, rotor speed, DC bus voltage and circulation current was performed for better system performance. Finally, simulations were performed in a computational environment, through the software PSIM ®. Editor: Universidade Federal da Paraíba Tipo: TCC

2017-11-24T00:00:00Z Leandro, Guilherme Cirilo https://repositorio.ufpb.br/jspui/handle/123456789/13358 2019-02-09T06:04:25Z 2017-11-16T00:00:00Z

Título: Conexão de Gerador de Indução com Rotor Bobinado à Micro-Rede CC com Conversor Multinível Modular com Submódulos em Ponte Completa Autor(es): Leandro, Guilherme Cirilo Orientador: Rocha, Nady Abstract: In this undergraduate thesis a wind power generation system based on a doubly-fed induction generator connected to a DC microgrid using a modular multilevel converter was proposed. The proposed system was composed by: a stator-side converter, a rotor-side converter, a doubly-fed induction generator and a wind turbine. The topology of modular multilevel converter with full-bridge submodules was adopted as the stator-side converter, connecting the generator’s stator to the DC microgrid. Since a low voltage DC microgrid was considered, the connected wind power generators can have a line voltage higher than the microgrid, which makes necessary the voltage step-down rectifier operation of the modular multilevel converter. For the variable speed operation of the generator, a three-phase voltage source converter with three arms was used as the rotor-side converter, connected to the DC microgrid, performing the vector control of the generator. In order to increase the accuracy of the generation system, a wind turbine described by the two mass model was considered. A control system was proposed to balance the voltage of the capacitors of the modular multilevel converter, to ensure three-phase symmetrical voltages with a waveform close to a sinusoidal wave in the generator’s stator terminals, and to obtain the value of the torque applied on the generator’s shaft for a wind velocity by the wind turbine. The modulation strategies for each submodule and for each leg of the modular multilevel converter were also discussed. To prove the operation of the control system, simulation results were acquired and analyzed. Editor: Universidade Federal da Paraíba Tipo: TCC

2017-11-16T00:00:00Z Freitas, Caio Augusto Fonseca de https://repositorio.ufpb.br/jspui/handle/123456789/13356 2019-02-09T06:04:08Z 2017-11-24T00:00:00Z

Título: Software Baseado em MATLAB® para Cálculo e Análise Tridimensional de Campos Elétricos e Magnéticos em Linhas de Transmissão Autor(es): Freitas, Caio Augusto Fonseca de Orientador: Braz, Helon David de Macêdo Abstract: With the publication of the report presented by Wertheimer and Leeper (1979) pointing to a possible association between childhood cancer and the electric and magnetic fields generated by power transmission lines, the concern about those fields has increased, leading to a number of studies on the subject. Although concrete evidence of this relationship was not found, rules were created establishing limits for human exposure to the fields generated by the transmission system. In order to comply with these standards, even at the designing stage, the fields are calculated and analyzed. The objective of this process is to verify whether the results meet the regulations or not. This work proposes a MATLAB® based software, which aims to facilitate this analysis. It calculates the fields generated by single and double circuit lines, and presents three-dimensional graphs as a result. The validation of the proposed software was made through case studies, in which three transmission lines of the Companhia Hidro Elétrica do São Francisco were analyzed, and the results were compared with reports about studies previously made by the company. Editor: Universidade Federal da Paraíba Tipo: TCC

2017-11-24T00:00:00Z