Navegando por Orientadores "ROCHA, Brigida Ramati Pereira da"

Agora exibindo 1 - 20 de 21

Acesso aberto (Open Access)
Análise de sensores de descargas atmosféricas: protótipo de um detector de raios com estimativa de densidade de raios para região amazônica utilizando PSoC
(Universidade Federal do Pará, 2014-02-24) LEAL, Adônis Ferreira Raiol; ROCHA, Brigida Ramati Pereira da; http://lattes.cnpq.br/9943372249006341
This work proposes the design of a prototype for detect lightning, which will, count the number of lightning detected, calculate the density of lightning to the area of operation of the sensor and to estimate the peak of the variation of the electric field for the instant occurrence of discharge. A study of atmospheric electricity, types of lightning, emission of electromagnetic waves during the occurrence of the lightning , types of electromagnetic sensors and lightning detection networks gave subsidy to the design of the prototype . The prototype consists of two antennas, one loop antenna and a flat plate antenna , and electronic circuits , these electronic circuits are implemented mostly in PSoC device ( Programmable System -on - Chip ) , which is a relatively new technology that works with analog and digital signals and also has a CPU to perform the processing of these signals . The validation of the data obtained and estimated coverage area of the sensor, were based on data from STARNET network (sferics Timing And Ranging NETwork). The prototype was designed to be low cost, have a simple and straightforward interface and can be installed in the Amazon region.
Acesso aberto (Open Access)
Análise de um modelo energético baseado no uso da biomassa residual local em comunidades isoladas no entorno da UHE de Tucuruí, PA
(Universidade Federal do Pará, 2017-01-16) BRASILEIRO, Bruna Chaves; ROCHA, Brigida Ramati Pereira da; http://lattes.cnpq.br/9943372249006341
The Amazon region, although its great environmental and economic importance, still has a low capacity for an effective implementation of inclusive energy actions to provide greater economic and social development directed mainly to traditional Amazonian populations. The purpose of this dissertation is to study the potential of the existing resources in favor of isolated communities through of the Integrated Resource Planning, since locally available energy resources do not receive enough attention and investments because they are considered low-profit markets making it dependent on fossil fuels. The research analyzed a case study performed in Tucuruí municipality, Pará State, where the second largest Brazil hydropower plant (with an installed capacity of 8.370 MW) is located, which creates a scenario of social-spatial conflicts involving many groups, including traditional populations that are affected by the construction of the power plant. The studied area is located on islands around the lake of the Hydroelectric Plant of Tucuruí, forming the Alcobaça Sustainable Development Reserve (SDR). Resident populations in these islands face difficulties on accessing electricity, as well as precariousness of public services in health, sanitation, infrastructure and education. Most of the region's families survive on even minimum wages monthly and often rely on local trade for the outflow of production, especially fish. A research study was conducted to examine a feasible model for the region, focused on the use of the local potential of biomass (açaí lumps) for electric power generation in isolated residences.
Acesso aberto (Open Access)
Aproveitamento da biomassa flutuante do Rio Madeira para geração de energia elétrica
(Universidade Federal do Pará, 2010-05-24) BACELLAR, Atlas Augusto; ROCHA, Brigida Ramati Pereira da; http://lattes.cnpq.br/9943372249006341
The universal provision of electricity remains far from achieved in the Brazilian Amazon, given the geographical obstacles, the dispersion of its inhabitants, the indistinctness of appropriate technologies, and the economic obstacles. Governmental action was taken in 2003 with the creation of the Light for All Program (PLpT), with the goal of bringing electricity to all rural consumers by 2010. In addition, the National Electric Power Agency, ANEEL (Agência Nacional de Energia Elétrica), which is responsible in Brazil for the electrical sector regulation, has issued a determination of compulsory access to electricity by 2015. This study describes research conducted on the Madeira River, in the Brazilian Amazon, where the electric needs of the communities and small towns along the river can be satisfied through the gasification system, using as a renewable feedstock the wood-fuel biomass deposited on the riverbed, derived from natural processes, which the Ministry of Transport is already legally obligated to remove in order to provide safe navigation along the river. The first part of the study was dedicated to review Brazilian power system, Universal access to electricity in Brazil, renewable sources of energy in the Amazon region, technologies to produce electricity using biomass as source, Brazilian power sector subsidies, the Madeira River, its characteristics and economic importance and investment analysis tools. Next, quality and quantity information of the biomass collected from the river along the years was taken from AHIMOC, the Federal Organization responsible for the Madeira River navigability. Then a physical-chemical analysis was made at the UFAM’s laboratories, using biomass collected in a field trip. The biomass power potential and the technological power production routes using biomass were evaluated with these data after comparing the results with available literature. Subsequently information about householders and communities located at the Madeira River was obtained with the State Utility. Once the available biomass, the technology routes and the possible consumers were characterized, the study evaluated technology, economy, environment, social and legal aspects. The study results show the competitiveness of gasification comparing to diesel thermoelectric plants, along with its advantages in helping Brazilian universal electrification program, which implementation depends on public policies with the obligatory participation of the Ministry of Mines and Energy, Ministry of Transports and The Ministry of Environment, and also the attractiveness potential private capital participation which could contribute to reduce public investment. The results should help future studies in others areas with similar phenomena and the opportunity to use another types of local biomass in Gasifier systems.
Acesso aberto (Open Access)
Atendimento de energia elétrica domiciliar para comunidades isoladas de baixa potência do interior do estado do Pará através de um gaseificador de 1kw
(Universidade Federal do Pará, 2006-12-11) BRITO NETO, Osmundo Batista de; ROCHA, Brigida Ramati Pereira da; http://lattes.cnpq.br/9943372249006341
In Pará State, almost 21% of its population has no access to use of electric energy in their residence. To this universe belongs the target audience from this report, that are the isolated communities. Due the large territorial extension and hydrographic basin in Pará State, this communities will have many difficulties to be served by the extension of distribution network. The proposal of this report consists in the use of the Açaí seed as biomass to an Indian co-current and open top gasifier of 1 Kg/hour, adapted and adjusted to the specifications of this region; the gasification system is connected to a generator of 2 KVA (Diesel or Gas), to supply with electric energy for the isolated communities where already exists the biomass as a result of the Açaí seed processing that is been considered as garbage. In this context, the governmental programs were examined in order to support this proposal, using the proposed system as one of many options to serve with electric energy by alternative source.
Acesso aberto (Open Access)
Classificação automática de cobertura vegetal em imagens aéreas e orbitais para uso em planejamento energético
(Universidade Federal do Pará, 2011-01-20) SANTOS, Neuma Teixeira dos; ROCHA, Brigida Ramati Pereira da; http://lattes.cnpq.br/9943372249006341
In this work, a model of neural network for energy planning and construction of energy scenarios is presented. This model permited the identification and clustering of representative pixels of water, vegetation, and anthropic impact around Tucuruí reservoir, located in the Tocantins River basin , (State of Pará, Brazil) . The database consisted in orthorectified aerial photographs and clipping of Landsat satellite’s images. Both were obtained in August 2001 and the two set of images were classified using the method of metric of the minimum distance with Matlab 7.3.0 (Matrix Laboratory – Applied mathematics software) and Arcview 3.2a (Geographic Information Systems Program). Then a competitive neural networks of Kohonen was used to classify the different areas in Matlab. This specific network allowed to map the area in n-dimension (number of entries) for a m-dimensional space (number of outputs). The results obtained with Matlab were compared with the output of Arcview classifier software. The results obtained using the neural network in Matlab and the Arcview classifier were similar, but some differences between the images in high and medium resolution were observed; these differences can be justified by the fact that the images in high spatial resolution cause many spectral variations in some features, creating ratings problems. This automatic classifier appears to be a good tool for the identification of the biomass potential for the construction of energy scenarios. The results of this work could confirm that the images in medium-resolution are the most suitable to solve the most of problems which involve the identification of land cover for energy planning.
Acesso aberto (Open Access)
Desafios e oportunidades para o acesso universal à energia elétrica na Amazônia
(Universidade Federal do Pará, 2015-02-20) MUNIZ, Rafael Ninno; ROCHA, Brigida Ramati Pereira da; http://lattes.cnpq.br/9943372249006341
The Brazilian energy planning has been progressively emphasizing the use of renewable energy sources, however for some initiatives such as the Light for All Program, these energy alternatives are being treated as a secondary activity and difficult to implement. This work aims to analyze how the Brazilian government has been adapting its institutional structure, technology and funding to provide universal access to electricity in remote areas. According to official information, this initiative has proven effective in its first phase, which was developed by the extension of conventional network. However, the study concludes that the program is currently not converges to full compliance with the access to electricity in remote areas in the Amazon and three main challenges were identified. There is a need for adjustment of current institutional structures, harmonize technologies to the regional context and use government funds more effectively. The research points out ways and alternatives to what is being done in isolated systems, and presents two case studies which have been applied to decentralized power generation with renewable sources of biomass in isolated community, and the energy utilization of municipal solid waste in the municipality belonging to the isolated system. These practical examples are proposed to contribute to the results of the study for the development of public policies, research projects, meet technology providers and promote energy and residuary solutions for municipalities and communities belonging to national isolated system, aiming to achieve universal access to energy electricity in remote areas in the Amazon.
Acesso aberto (Open Access)
Elementos de sensores de eletricidade atmosférica
(Universidade Federal do Pará, 2010-05-18) PEREIRA, Carlos Simões; ROCHA, Brigida Ramati Pereira da; http://lattes.cnpq.br/9943372249006341
The electromagnetic environment surrounding the planet Earth has a fundamental role in the preservation and development of the living creature, and perhaps the last frontier of human knowledge to be dominated completely, before we ventured to the space outside in search of new opportunity outside. This environment is only now being tamed and best known, and this endeavor has as lynch pin the use of appropriate sensors that can detect and quantify these electrical effects, to serve as a basis for the generation of theories, to explain the underlying phenomena, including in this, the sensors of atmospheric electricity. This work intends to make a comprehensive analysis of these sensor’s systems of atmospheric electricity in use today, evaluating their models of operation, its limitations and its intelligence, and producing a summarized basic specifications for development of better sensors and setting standards for metric types of the variables to be measured, to cope with the currents and future demands in this field of knowledge. Additionally, the processes involved in the calibration of these sensors will be addressed with a review of computational model based on the method of moments (MoM) and other that my be used for evaluation of electromagnetic fields emitted by remote charges patterns and electrical currents, which serve to support and basis for these calibrations.
Acesso aberto (Open Access)
Estimação do local de incidência da descarga atmosférica utilizando o método TOA e tempos artificiais de detecção dos sensores
(Universidade Federal do Pará, 2016-03-22) MIRANDA, Bruno Nazareno Prazeres de; MACEDO, Valquiria Gusmão; http://lattes.cnpq.br/4288739747304808; ROCHA, Brigida Ramati Pereira da; http://lattes.cnpq.br/9943372249006341
Over the years, lightning were the central point of researches in various scientific communities around the world, no doubt for its aggressive and devastating nature, but mostly for damage caused in the electricity sector, so it is necessary to clarify what is and what it is for a Lightning Location System (LLS). This work proposes to demonstrate the operation of the algorithm utilized in LLS that is used to locate in geographical terms, lightning, using the arrival times of electromagnetic signals in the sensors. In order to prepare this paper it was used the data format generated by LPATS IV sensors belonging to Amazon Protection System (SIPAM). These data were generated in an artificial way for use in the algorithm tests. The lightning location will be based on a finite sequence rules that use the intersection of hyperbolas, resulting from the difference of arrival times at each sensor. The algorithm is able to identify the lightning location incidence using a system with three sensors. Each pair of sensors defines two hyperbole forming a total of six, because each hyperbole has a bright side and a negative side, so there will be two intersections of three hyperboles. For analysis of the results is considered the nearest crossing point to the sensor that identified the electromagnetic disturbance faster. Studies about atmospheric electricity, lightning types, electromagnetic radiation during storms, types of electromagnetic sensors and lightning detection networks have given the knowledge to develop the algorithm.
Acesso aberto (Open Access)
Estudo dos efeitos das descargas atmosféricas nos índices de desempenho da Subestação de Vila do Conde
(Universidade Federal do Pará, 2014-09-11) PEREIRA, Jorge Luiz Moreira; ROCHA, Brigida Ramati Pereira da; http://lattes.cnpq.br/9943372249006341
This work aims to present the effects of lightning performance indexes in VDC (substation of Vila do Conde), located in the northern region, in the State of Pará, in the period from 2005 to 2013, establishing the relationship between the weather information provided by the SIPAM and data provided by the center of operations for Eletronorte in order to perform and determine the harmful effects of atmospheric discharges, which are responsible for the intensification of interruptions in the supply of electricity.The analysis is restricted to the area of expertise of Eletronorte (substation of Vila do Conde) which has much of its power transmission Lines installed in northern Brazil. The results show that the incidence of lightning can cause direct and indirect surges in transmission lines and substations of high power. In this context justifies the study of efficient forms of prevention, being one of the purposes of this work, which aims to provide general information concerning the effects produced by the action of atmospheric discharges in substations of the power sector as the quality of energy, in particular in the VDC – Eletrobrás System-Eletronorte.
Acesso aberto (Open Access)
Estudos dos efeitos das descargas atmosféricas nos índices de desempenho da subestação de Vila do Conde e subestação de Marabá
(Universidade Federal do Pará, 2016-05-10) SANTOS, Luciano Silva dos; PROTAZIO, João dos Santos; http://lattes.cnpq.br/4210442535067685; ROCHA, Brigida Ramati Pereira da; http://lattes.cnpq.br/9943372249006341
This paper aims to present the effects of lightning in the performance indices in Vila do Conde substation (SE VDC) and Maraba (SE MB), which are situated in the north, in the state of Pará, integrating the North System - Eletronorte Transmission northeast, being connected to the Tucuruí Hydroelectric Power Plants (HPP Tucuruí). They were studied, establishing relations between the weather information provided by the SIPAM and data provided by central Eletronorte's operations in the period 2005-2013 in order to determine the harmful effects of lightning, which are responsible for the intensification of supply interruptions electricity. The analysis restricted to the area of operation of Eletronorte SE and SE VDC MB. The study developed evidence disconnections by lightning on transmission line VDC / CASTANHAL 230 KV and 500 KV breaker VCDJ7-08 and transmission line MB / Empress of 500 KV. The results demonstrate that a lightning strike may cause direct and indirect surges in transmission lines and high power substations. In this context it justifies the study of efficient forms of prevention, one of the purposes of this work.
Acesso aberto (Open Access)
Geração de energia elétrica a partir dos resíduos do processo de beneficiamento do óleo de palma: uma abordagem sustentável para a recuperação de áreas degradadas no Estado do Pará
(Universidade Federal do Pará, 2017-01-16) KÜHL, Ricardo Marino; ROCHA, Brigida Ramati Pereira da; http://lattes.cnpq.br/9943372249006341
The deforestation, mainly verified in the Amazon region, has declined, but deforested areas, due to anthropic actions such as agriculture, or pastures opening, are still a hindrance, since the resilience process requires time to act. In this bias, the Agroecological Zoning, Production and Management of Oil Palm Culture in Amazon (ZAE-Dendê), evaluated the degraded areas in the Legal Amazon, aiming the palm plantation to recover them, based on the best practices. The present work goes beyond, evaluating the implantation of palm oil as a way of recovering degraded areas in Pará; the power generation from palm oil processing residues; as well as analyzing carbon dioxide reducing potential. The methodology used, covered the selection of degraded areas in Pará as the study area. Based on theoretical references some data were consolidate: the production of fresh fruits bunches (FFB) per hectare, the amount of waste per tonne of FFB, power generated from the residues and CO2 value fixation and emission. The results related to the CO2 emissions and fixation showed that the palm oil culture has the potential to reduce a range from 180 to 500 million tons of CO2eq., in addition to avoiding emission of 550 to 2,204 million tons of CO2eq., in a production cycle (25 years). The power generation potential verified from the anaerobic digestion of the liquid effluent range from 212 to 531 TWh during a palm oil production cycle. These data attests palm oil residues to become an alternative energy resource, as well as an alternative to degraded areas recovery. Therefore, this work is a subsidy for an Integrated Resource Planning elaboration.
Acesso aberto (Open Access)
Metodologia integrada utilizando sensoriamento remoto em redes neurais artificiais na quantificação do potencial de biomassa florestal na Amazônia
(Universidade Federal do Pará, 2008-04-08) ALMEIDA, Arthur da Costa; ROCHA, Brigida Ramati Pereira da; http://lattes.cnpq.br/9943372249006341
Pattern recognition and pattern classification in digital images is a very important skill, today. With them, it is possible to recognize and identify target objects in those images. This work proposes an integrated methodology for pattern recognition related to biomass in the Amazon tropical rainforest to extract information about bioenergetics potential for electric energy production for use with isolated Amazonian communities. To achieve this aim, information gathered about forest inventory was mixed with pattern classification and recognition in medium resolution satellite imagery such as those from LANDSAT and CBERS. The approach used in this work comes from the computational intelligence area, using artificial neural networks equipped with radial basis functions and Kohonen´s self organizing maps. The results serve as input to a geographical information system application which creates and manages a geographical database for energetic planning with renewable energy resources applicable to isolated Amazonian communities.
Acesso aberto (Open Access)
Modelagem de sistemas de detecção de descargas atmosféricas na Amazônia
(Universidade Federal do Pará, 2013-12-18) DENTEL, Laure Madeleine; ROCHA, Brigida Ramati Pereira da; http://lattes.cnpq.br/9943372249006341
Lightning is one of the greater risk factors for the Electricity Sector, especially in the Amazon, a region of the world identified with high lightning densities and peak currents. In this context, the Sferics Timing And Ranging NETwork (STARNET), which is presently the only free and continuous lightning detection system covering the whole Amazon Region was chosen to generate lightning parameter products required for the optimization of protection for transmission lines systems through continuous lightning monitoring. However, the intermittent activity observed in the Operating Diagrams of the various STARNET stations, impacted the system performances in special its detection efficiency. As a consequence, a model of standardization of lightning data was developed as a function of the network configuration (number and location of sensors in operation), with the final objective of editing reliable keraunic parameter as well as lightning densities maps. We found that there are Amazon regions which always have positive lightning density anomalies like the regions of Belém and Manaus, and the state of Tocantins. Next, the lightning incidence on transmission lines in amazon region was estimate from the peak current distribution of the Lightning Detection Network of the Amazon Protection System (SIPAM-LDN) and the standardized stroke density from the STARNET network. A comparative performance evaluation of STARNET with reference to the SIPAM-LDN also showed a strong dependence of the lightning detection efficiency of STARNET network on the peak current of lightning events.
Acesso aberto (Open Access)
Modelagem do potencial de geração de energia hidrelétrica: uma contribuição para o planejamento energético na Amazônia
(Universidade Federal do Pará, 2019-05-08) LOPES, Márcio Nirlando Gomes; ROCHA, Brigida Ramati Pereira da; http://lattes.cnpq.br/9943372249006341
The feasibility studies for hydroelectric power plants (HPP) use observed flow data to estimate the potential for energy generation. According to the Brazilian rule, the records need to cover a minimum period of seventy years of observation. However, in some regions the flow records comprise short periods, so that the time series does not capture the natural variability of the climate and this can lead to errors in the interpretation of the information, such that the power generation of the plant can be lower than expected. To address this problem, this thesis proposes an innovative methodology to estimate the potential of power generation. The principle is to use precipitation data, which has long time series, to estimate the potential of power generation through a modeling that employs artificial intelligence techniques. Two distinct methods of machine learning were tested. The first is a deep learning technique called Group Method Data Handling (GMDH). The second uses artificial neural networks with distinct options for optimization algorithms, Levenberg-Marquardt and Bayesian regularization. The methodology was applied to the Jatobá hydroelectric project in the Tapajós river basin in Pará. The evaluation indicators showed that the models have the skill to simulate the power generation, with a better performance for the GMDH, which reached 95% correlation with the actual data and only 12% average error percentage. The simulations obtained better performance during the dry season, which is fundamental, since this critical period for the generation of hydropower defines the firm energy of the enterprise. Statistical analysis on the observed data detected a significant tendency of precipitation reduction in some sub-basins of the Tapajós River. Simulations incorporating a climate change scenario proposed by the Intergovernmental Panel on Climate Change, as well as a scenario of long-term statistical trend, both indicated a reduction in power production capacity for the next twenty years, suggesting that the HPP Jatobá may not meet the project's firm energy demand for long-term under such conditions. The success of this approach can contribute to reducing uncertainties and subsidizing preliminary studies for the implementation of hydropower plants, as well as simulating scenarios to support planning, reduce costs and generate synthetic data for time series of power generation covering periods without observational field data.
Acesso aberto (Open Access)
Otimização da detecção de formas de onda de campos eletromagnéticos emitidos por descargas atmosféricas
(Universidade Federal do Pará, 2018-01-23) LEAL, Adônis Ferreira Raiol; RAKOV, Vladimir; ROCHA, Brigida Ramati Pereira da; http://lattes.cnpq.br/9943372249006341
This work aims the application of optimization techniques to detect and record lightning electromagnetic waveforms. As a result of the optimization techniques developed on this Thesis, it is presented the “Lightning Detection and Waveform Storage System - (LDWSS)”. The main optimized points were: cost of the device; improvements of its detection dynamic range; development of a mobile device; possibility to detect in a multi-band way; and calibration in order to infer peak currents from remote measurements of lightning electric fields. The developed system was validated through comparison of a return stroke data in lightning triggered using the rocket-and-wire technique at the International Center for Lightning Research and Testing - ICLRT, of National Lightning Detection Network – NLDN data, and data from the Lightning Observatory in Gainesville - LOG. The main usage of the optimized system is on the investigation of lightning physics and effects, mainly in the Amazon region. As a result of using the system were obtained: a better understanding about Compact Intracloud Discharge - CID; the characteristics of ionosphere heights computed using intraclound and cloud-to-ground lightning electric field waveforms; the conception of a lightning electric field waveform database containing more than 8 thousand waveforms of different types of lightning; and the implementation of the first continuous lightning electric field measurement system in the amazon region, localized at CESIPAM, Belem, PA.
Acesso aberto (Open Access)
Planejamento de sistemas de proteção contra descargas atmosféricas para unidades habitacionais de baixa renda
(Universidade Federal do Pará, 2014-02-24) SANTOS, Diego Guimarães dos; ROCHA, Brigida Ramati Pereira da; http://lattes.cnpq.br/9943372249006341
This research have the purpose to realize a study about the lightning occurrence profile over the municipalities of Belém, Ananindeua and Marituba, in the period of 1991 to 2011 with the objective to establish the lightning occurrence profile in these municipalities, as well as identify what kind of factors need to be observed and/or identified with the finality to realize an appropriate planning of protection systems against lightning in low income housing builded by the acceleration program of development from the federal government, more precisely in Taboquinha housing, located on the district of Cruzeiro in Icoaraci. After the realization of the comparative analysis with lightning occurrence data proceeding from the lightning detection network STARNET, lightning occurrence data from LIS sensor installed on board of the TRMM satellite, as well as lightning data acquired by the Brazilian Association of Technical Standards NBR 5419, it was possible to conclude that the Taboquinha housing need an appropriate protection system against lightning due to sinister occurrence records involving direct incidence of atmospheric discharges, as well as your secondary effects. In the end of this research will be presented some discussion topics related with some conclusions about the lightning occurrence profile in the present region presented by the NBR 5419 standard, because this incoherent conclusion may harm the public patrimony, as well as the common citizen and their construction.
Acesso aberto (Open Access)
Planejamento energético para pequenas comunidades da Amazônia: um estudo de caso da comunidade quilombola de Genipaúba - Abaetetuba - Pará
(Universidade Federal do Pará, 2008-12-09) MONTEIRO, José Humberto Araújo; ROCHA, Brigida Ramati Pereira da; http://lattes.cnpq.br/9943372249006341
The energy assistance to isolated communities has always been an activity difficult to implement and has been the target of criticism by the authorities in energy planning. This dissertation aims to contribute for to the discussions on the issue of electrification of remote areas through the presentation of social diagnosis and energy planning to the community of Genipaúba, located in the islands of Abaetetuba, municipality of the State of Pará A discussion on the relationship between energy and development starts the dissertation, which is followed by a successful completion of an inventory of energy resources in the region, based on existing literature. Government programs for rural electrification (Luz no Campo, Ribeirinhas, PRODEEM, and Luz para Todos) is showed. Management models investigated surveyed (PRISMA and ROSA) were idealized by observations from the implementation of projects for electrification. Social and energetic diagnosis for the community of Genipaúba was accomplished through the use of questionnaires filled in the field. The implementation process of the energy project for Genipaúba is presented and then compared with the models studied in order to give consistency to it.
Acesso aberto (Open Access)
Planejamento para minimização de fatores de riscos relacionados a descargas elétricas em programas de habitação e urbanização no Estado do Pará
(Universidade Federal do Pará, 2014-08-27) MELO, Rezerneide Guimarães; ROCHA, Brigida Ramati Pereira da; http://lattes.cnpq.br/9943372249006341
The homeownership represents family security for many Brazilians. It is a durable and transferable, therefore is need to maximize safety for the prevention of accidents involving people or structure. Reduce the housing deficit is part of the mission of housing programs in Brazil. These are financed with public money, is also defined the electrical safety of the property. National statistics indicate that electrical accidents can lead to serious and irreversible situations. Faced the context, planning for minimization of risk factors related electrical discharges in residential units of housing and urban development programs in the State of Pará is justified. This work, are discussed the circumstances of electrical accidents in the Pará, in order to direct prevention measures and techniques of electrical safety recommendations for affordable housing. A sample was purposively selected, among the enterprises of housing provision of the PAC Phase 1 and PMCMV Track 1 located in the municipalities of Belém and Santa Isabel do Pará, for to be the object of study, by to represent the electrical needs of a large city and of the a municipality with less than seventy thousand inhabitants. The instrumentation of the questionnaire on "Risk Factors Electric" among beneficiaries of affordable housing, at least with one year of residence, between the months of October and December 2013. Allowed the discussion related the verification of residential electrical design and analysis of the circumstances of the occurrence of electrical accidents on Pará (retroactive period of ten years). Resulting in technical recommendations on residential electrical safety, for which we considered the literature review and the economic, social and environmental characteristics of the Amazon Region. During the technical analysis were not found serious non-conformities with NBR 5410:2004 and NBR 5419:2005, but it was evident the need to think of popular models of home, principally, electrical safety projects that consider the needs and socio-environmental characteristics of the Amazon Region.
Acesso aberto (Open Access)
Processo de attachment, densidade de raios e a ocorrência de flashover em linhas de transmissão de eletricidade
(Universidade Federal do Pará, 2014-12-19) PEREIRA, Carlos Simões; ROCHA, Brigida Ramati Pereira da; http://lattes.cnpq.br/9943372249006341
This thesis refers to the use of leaders attachment model (Leader Progression Model - LPM) in the estimation of striking distance values and jointly use of lightning density data gathered by a LLS System to estimate the flashover rate of electricity transmission lines in the Amazon region. The leader progression model developed here is called ModSalto, and to estimate the striking distance, it: integrate the linear density of the leader electric charge proportional to the prospective lightning first stroke (Ip) to estimate the electric field produced by the descending leader, in the tip of the structure under study (arrester, electric conductor, etc.); makes integration of the image leader charge distribution and makes use of the power of tips as a stimulus and intensification factor for the electric field due to the streamers on the edge of the structure under study, to time the attachment process. The trigger of the descending leader is hypothesized to be on behalf of packets of charges turbulent domains in cloud, and the leader's behavior on the descending path is hypothesized to obey the equation of the Lorentz force in the space of movement of electric charges of the leader, influenced by crossed electric field due to the electrification of the clouds and the Earth's magnetic field, which imprints a cycloid motion on the leader’ tip electric charges which may explain the stepped and tortuous nature of the downward leader. The LFR parameters (Lightning Flashover Rate) is presented as an estimate of the probability of occurrence of flashover induced by lightning on an electric transmission line, that may be derived by a defined parameter Jv (Vulnerability Window) as a quantifying factor to the probability of insufficient protection provided by the EGM model to the transmission line, protected against lightning with use of shielding conductors (shield wire). With the aim to get a usable lightning density data, we do a reanalyze of the dataset of occurrence of lightning collected by LLS SIPAM, from October 2006 to July 2008 in the amazon region, with over 3 million hits, comparing them with data from instrumented towers allowing an assessment of the quality of such data. Terrain elevation data (SRTM) from NASA are used to generate attraction radius (Ra) formulas that takes into account the height of the structures and jointly with Log Normal distribution parameters describing the statistical behavior of first pulse current values (stroke) of the lightning, as estimated by LLS SIPAM, to generate a summation or integration area of attraction formula, used in the quantification of the number of lightning which are likely to hit a given structure, depending on the density of lightning (lightning / km2 / year) at the study site.
Acesso aberto (Open Access)
Um simulador para avaliação da influência das características locais das descargas atmosféricas nuvem-solo em sistemas de detecção indireta
(Universidade Federal do Pará, 2017-01-10) SHINKAI, Ricardo de Andrade; ROCHA, Brigida Ramati Pereira da; http://lattes.cnpq.br/9943372249006341
The monitoring of the phenomenon of atmospheric discharges has been fundamental to prevent incidents in the infrastructure of companies that operate in large areas, such as energy, telecommunications and information technology. In addition, it provides data for the planning of lightning protection systems, thus avoiding further damage to life on Earth, and more recently providing information for weather warning systems such as short-term storm forecasting. Therefore, it is no longer a matter of choice, but rather the need to install and maintain systems that supervise these events on a local, regional and even national scale. Among the possible types, the Lightning Location Systems are the ones that provide more accurate information in the mentioned scales, because they work with the perception of the electromagnetic impulse generated by the lightning. This signal has the property of propagating at medium and long distances in certain frequency bands, maintaining good the information quality of the phenomenon that originated it. However, the phenomenological characteristic of the lightning is intrinsic to the monitored area, making fundamental the understanding of these specificities to better benefit the mentioned systems. This work presents a computational tool to simulate the influence of local characteristics on the propagation of electromagnetic waves caused by cloud-to-ground lightning. The methodology was used to simulate the propagation of these waves through the MATLAB® program, using as model of return current in the discharge channel the model of engineering type the Transmission Line (TL) to represent the electric phenomenon generated by thelightning.