Regulador eletromagnético de frequência aplicado no controle de velocidade de geradores eólicos

The constant necessity for new sources of renewable energy is increasingly promoting the increase of investments in this area. Among other sources, the wind power has been becoming prominent. It is important to promote the search for the improvement of the technologies involved in the topologies of the wind turbines, seeking for alternatives which enhance the gotten performance, despite the irregularity of the wind speed. This study presents a new system for speed control, in this case applied to the wind turbines - the Electromagnetic Frequency Regulator (EFR). One of the most used devices in some topologies is the mechanical gearboxes which, along with a short service life, often represent sources of noise and defects. The EFR does not need these transmission boxes, representing a technological advancement, using for that an adapted induction machine, in which the stator becomes mobile, supportive to the axis of the turbine. In the topology used in this study, the EFR also allows us to leave out the usage of the eletronic converters to establish the coupling between the generator and the electrical grid. It also the reason why it provides the possibility of obtaining the generation in alternating current, with constant voltage and frequency, where there is no electrical grid. Responsable for the mechanical speed control of the generator, the EFR can be useful in other transmission systems in which the mechanical speed control output is the objective. In addition, the EFR operates through the combination of two inputs, a mechanical and other electrical. It multiplies the possibilities of application because it is able to synergistic coupling between different arrays of energy, and, for such reasons, it enables the various sources of energy involved to be uncoupled from the network, being the synchronous generator responsible for the system connection with the electrical grid, simplifying the control strategies on the power injected in it. Experimental and simulation results are presented through this study, about a wind turbine, validating the proposal related to the efficience in the speed control of the system for different wind conditions.

Estudo de viabilidade técnico-ambiental para implantação de parques eólicos: um estudo de caso em um fragmento do litoral setentrional do Rio Grande do Norte/Brasil

The use of energy from renewable sources is increasingly demanded by society, especially aeolian - whose raw material is wind. Investments in wind power have become significant in Brazil with emphasis on the Northeast and in particular the Rio Grande do Norte state. According to the Empresa de Pesquisa Energética (Energy Research Company) (2012 ) , investments in the state grew significantly since 2002 with a total accumulated power, by 2013, of approximately 3,400 MW . Even with the early experiences of exploitation of wind energy in 2002, it is still considered new and requires further study referring to the likely changes in the environment and society. In this case, it is of growing and urgent importance to deeply study the wind still in the survey phase of the project, ie , at the beginning of decision making on the most feasible to implement these parks site. Given the above, the question is: from a technical and environmental analysis, how to identify viable areas to install Aeolian parks, taking into account the factors of the environmental dynamics that are relevant to minimize the negative results to the environment and the society? Thus, this study conducted a study on technical and environmental feasibility, proposing a methodology of exploration of feasible wind farms in coastal areas. The study area was a fragment of the northern coast of Rio Grande do Norte and its natural landscape units were identified through the environmental characterization of the area, as well as it was elaborated the map of the land cover, restriction homes and urban areas and Permanent Preservation Areas - PPAs. The environmental fragility was subdivided in the fragility of the natural dynamic, mapped through relief, soils and geology of natural units, and the fragility of the ecosystem, originated by the land cover map. In addition to these maps, it was generated the wind resource for an area from a height of 50 and 100 meters. The intersection between the fragility maps, PPAs and Restriction of homes superimposed on maps of wind potential, provided the map of feasibility of Aeolian parks, resulting in the most favorable areas for its facilities in a technical and environmental point of view. From this study, the entrepreneur can evaluate whether or not to proceed with the studies in this area and especially decrease potential conflicts with society.

Aplicação do exame da proporcionalidade diante da implantação de empreendimentos eólicos em áreas de preservação permanente

The setting up of wind power enterprises at Permanent Preservation Areas reflects the obvious conflict and necessary convergence between free market and energy security on the one hand, and the promotion of environmental quality on the other. From the perspective of energy sustainability, and in order to achieve development (in its complex meaning, which converges economic, social, environmental and cultural aspects), the harmonization between free market and an ecologically sustainable environment is required. This work aims to identify the link between the protection system of the Permanent Preservation Areas and the current constitutional order, by analyzing the implementation of wind power enterprises in these protected zones focusing on the proportionality aspects. A legal and purposeful research was developed, from a theoretical method, followed by collecting and analyzing both primary and secondary data. From these data, the law, the legal literature and judicial decisions were cross-examined, under the light of the Constitution and guided by the theory of proportionality and related development imperatives. In this context, the present study identified the link between the principles of the economic order, environment and energy law, finding their basis under the Federal Constitution and development. By reproducing this interrelationship and by means of post-crisis institutional reforms, the guiding objectives of the Brazilian electric sector began to corroborate the precepts of development, although issues regarding its sustainability still persist. The appraisal of proportionality indicates that the Permanent Preservation Areas protection system is insufficient to materialize the right to a healthy quality of life upon the implementation of wind projects at Permanent Preservation Areas, albeit seeking the harmonization between free market and environmental protection.

Aplicação do exame da proporcionalidade diante da implantação de empreendimentos eólicos em áreas de preservação permanente

The setting up of wind power enterprises at Permanent Preservation Areas reflects the obvious conflict and necessary convergence between free market and energy security on the one hand, and the promotion of environmental quality on the other. From the perspective of energy sustainability, and in order to achieve development (in its complex meaning, which converges economic, social, environmental and cultural aspects), the harmonization between free market and an ecologically sustainable environment is required. This work aims to identify the link between the protection system of the Permanent Preservation Areas and the current constitutional order, by analyzing the implementation of wind power enterprises in these protected zones focusing on the proportionality aspects. A legal and purposeful research was developed, from a theoretical method, followed by collecting and analyzing both primary and secondary data. From these data, the law, the legal literature and judicial decisions were cross-examined, under the light of the Constitution and guided by the theory of proportionality and related development imperatives. In this context, the present study identified the link between the principles of the economic order, environment and energy law, finding their basis under the Federal Constitution and development. By reproducing this interrelationship and by means of post-crisis institutional reforms, the guiding objectives of the Brazilian electric sector began to corroborate the precepts of development, although issues regarding its sustainability still persist. The appraisal of proportionality indicates that the Permanent Preservation Areas protection system is insufficient to materialize the right to a healthy quality of life upon the implementation of wind projects at Permanent Preservation Areas, albeit seeking the harmonization between free market and environmental protection.

Precificação da energia eólica offshore no Brasil

Offshore wind power emits low amounts of gases, is renewable and has better performance than onshore due to its greater stability and higher wind power density, less visual and noise impact, among others. Brazil has a high capacity of generation, but has not yet developed any offshore projects. High costs are a strong impediment. This study is an effort towards pricing offshore resources through Livelized Cost of Energy - LCOE, which represents the minimum return to cover the costs of development, production and maintenance of a wind project. Initially LCOE was calculated for all Brazilian onshore wind farms listed at Bloomberg New Energy Finance R○, accounting for 71 farms. Then hypothetical offshore wind farms were created from the onshore farms, tripling the cost of generation, which is consistent with the literature, and estimating the offshore energy for two locations off the Brazilian coast using satellite data extracted from National Oceanic and Atmospheric Administration. The results demonstrate that offshore resources have the potential to significantly reduce the energy price due to the better performance of the wind at sea