Modelagem e análise dinâmica de um sistema de conversão de energia eólica dotado de gerador síncrono de imã permanente utilizando a plataforma ATP

Human development requires a broad balance between ecological, social and economic factors in order to ensure its own sustainability. In this sense, the search for new sources of energy generation, with low deployment and operation costs, which cause the least possible impact to the environment, has been the focus of attention of all society segments. To do so, the reduction in exploration of fossil fuels and the encouragement of using renewable energy resources for distributed generation have proved interesting alternatives to the expansion of the energy matrix of various countries in the world. In this sense, the wind energy has acquired an increasingly significant role, presenting increasing rates of power grid penetration and highlighting technological innovations such as the use of permanent magnet synchronous generators (PMSG). In Brazil, this fact has also been noted and, as a result, the impact of the inclusion of this source in the distribution and sub-transmission power grid has been a major concern of utilities and agents connected to Brazilian electrical sector. Thus, it is relevant the development of appropriate computational tools that allow detailed predictive studies about the dynamic behavior of wind farms, either operating with isolated load, either connected to the main grid, taking also into account the implementation of control strategies for active/reactive power generation and the keeping of adequate levels of voltage and frequency. This work fits in this context since it comprises mathematical and computational developments of a complete wind energy conversion system (WECS) endowed with PMSG using time domain techniques of Alternative Transients Program (ATP), which prides itself a recognized reputation by scientific and academic communities as well as by electricity professionals in Brazil and elsewhere. The modeling procedures performed allowed the elaboration of blocks representing each of the elements of a real WECS, comprising the primary source (the wind), the wind turbine, the PMSG, the frequency converter, the step up transformer, the load composition and the power grid equivalent. Special attention is also given to the implementation of wind turbine control techniques, mainly the pitch control responsible for keeping the generator under the maximum power operation point, and the vector theory that aims at adjusting the active/reactive power flow between the wind turbine and the power grid. Several simulations are performed to investigate the dynamic behavior of the wind farm when subjected to different operating conditions and/or on the occurrence of wind intensity variations. The results have shown the effectiveness of both mathematical and computational modeling developed for the wind turbine and the associated controls.

A dinâmica geográfica da construção de um território para moradias sociais: estudo testemunhal do empreendimento Vitória Brasil em Uberlândia (MG)

This work describes and analyzes the situation planned with the current, according to the housing development project style of social interest (Gleba 9), named Victory Brazil at Shopping Park II neighborhood, located in the southern sector of Uberlândia (MG), built with Program resources Minha Casa, Minha Vida (PMCMV). The specific objectives are: to present the housing policy of social interest directed to the Minha Casa, Minha Vida in the city of Uberlândia, from its history to its current information; trace the environmental characterization of the housing Vitoria Brazil through the development of thematic maps; identify the impacts generated by the housing projects of social interest; and show through interviews with 25 residents of Vitoria Brazil, the structural problems of the houses. Therefore, the research became quali-quantitative with descriptive approach and use of semi- structured interviews to collect data. In addition, the iconographic sources, ie photographs of the problems raised by the residents of the whole Victory Brazil and maps of the study area, enlarged the qualitative and dialogic nature of this study, as there is opportunity to contextualize specific way what was reported the residents interviewed. We understand that the city is intrinsically related to the design of agglomeration, characterized by the production of the possessor market capitalism a public administration system that is guided by the ideals of consumption and utilization of space, and its inhabitants are high class with the construction of equipment and adequate social services. One of the important biases to solving the problems of urbanization is by the intervention of the government through public policies through the master plan so that would allow prospects to enable the population of low-income housing in locations that offer housing and decent urbanization conditions.