Iluminação de exteriores utilizando tecnologia LED: estudo de caso

This Graduate Work aims to exhibit the analyze of the applicability of LED technology in a real outdoor lighting situation, and this project’s illumination solution is compared with the initial proposal, the sodium vapor lamps. What is studied is an outdoor area, like the roads and parking lots of a plant. A light planning software is used for this comparison, and the results are displayed instantly, allowing rapid analysis of the project through a simulation. The medium illuminance is the same in both solutions for this case study and minimum rates set as standard were observed then the analysis are appropriate in this project. Various aspects are considered in order to obtain a comprehensive analysis of this project, such as economic, environmental and quality of lighting. LED technology in outdoor lighting is presented in its infancy, but promising. Solid state lamps show great advantages when compared with other technologies, such as discharge lamps, however there are some disadvantages tied to new products that are expected to be overcome with technological development and increased production

Proteção de sistemas eletricos industriais: relés e suas aplicações em subestações

Electrical installations in industries involving high currents and voltages considered. On the other side is the common appearance of electrical failures, caused by human error, defects in electrical equipment or electrical installation aging itself. These failures are varied, those with the highest rate of occurrence and cause much damage to electrical installations, are overcurrent and overvoltage. Therefore there is a need to project a system that can detect and minimize possible effects caused by faults in electrical installations industries. Protection systems in electric industries emerge as an alternative to control especially voltage and current magnitudes. Engineered based on the functions of the relays, protection systems are an indispensable tool for any industrial substation. But the project of such systems becomes increasingly more complex, due to technological development. Electrical equipment not develop at the same speed that the protective devices (relays), making it indispensable knowledge of integration of technologies

Estudo da variação do limite de resistência à tração ao longo da bobina de vergalhão de alumínio 1350 AA

Therebar of aluminum 1350 AA produced by CBA are used inthe manufacture of wires and cables for electric power transmission, which marketshows increasingly favorableto aluminum due to itslow densityand high electrical conductivity, but to ensure that this materialmeets all specifications of projectsfor electricity transmission, it must have homogeneity in the chemicaland mechanicalproperties.One of the points of improvement in the process of rod production isreducing the high variation of the limitof tensile strengthalong the coils, therefore, this work seeks a better understanding of the factors that significantly influence the mechanical properties of rebar, specifically assessing the influence oftemperatureat the output of the coils, which can cause a recovery effect on the material andif thereare relevantdifferences between the two modes of rebar production: auto and manual.Samples of six coils have been specifically produced forthis study, which weresubsequently subjected to different annealing temperatures for one hour and ten minutes, similar to what occurs in the output of the coil from the machine. The tensile tests showed that aluminum 1350 AA is significantly influenced by temperature, whose behavior was very similar to that presented in the literature. It was found that the phenomenon of recovery occurred more significantly at high temperatures. Through the optical electron microscope Zeiss, 18 surface maps were made with 100x magnification for each sample in different conditions and the images were analyzed using entropy and fractal dimension, aiming to relate the condition of surface hardening on mechanical property of the samples in that condition. The results showed that these methods can be applied, provided they do not have any kind of imperfection on the surface, once they can influence the results. The study concluded that a more efficient cooling is required in ... (Complete abstract click electronic access below)

Análise da influência da iluminação de rodovias federais com a redução do número de acidentes

The increasing rate of traffic accidents, followed by the high rate of mortality due to these occurrences, favored to the classification of traffic accidents as a public health problem in Brazil. These accidents consume a significant portion of Gross Domestic Product (GDP), especially related to the victims. Considering this scenery with many tragedies and resources being spent only in the end, this paper seeks to examine the influence of federal highways lighting by reducing the number of accidents. Federal Highways sections that received lighting were taken up for study, therefore a survey of statistical data has been raised considering the accidents before and after the route had been illuminated. Taking advantage of the results obtained, an economic analysis has been made considering the amounts consumed by traffic accidents versus the values required for the installation of lighting on highways

Monitoramento hidrossedimentlógico da bacia hidrográfica do alto rio Sucuriú (MS) contribuinte da PCH Costa Rica

The growing demand for electricity in Brazil has stimulated the implementation of Small Hydro Power (PCH) in various regions of the country. However, the silting of reservoirs is a major problem faced by power plants and power plants. In this context, this study aimed to evaluate the data hydrosedimentological strategic points of the watershed of the Alto Rio Sucuriú (MS) to identify the possible causes siltation of the reservoir PCH Costa Rica and suggest mitigation measures. Hydrosedimentological surveys were conducted during the rainy season (February / March 2012) and drought (August 2012), and obtained data flow, discharge liquid, suspended solids and bottom and organic matter content. Based on these results it was determined that the points 2, 4, 7 and 9 are the largest contributors to sedimentation, and point 4 got most liquid discharge (38,20 m3s-1), point 7 largest discharge of solid suspension (906,3 mg L-1), points 2 and 4 major discharges solid totals (231,59 t dia-1 and 238,185 t dia-1 respectively) and point 9 higher organic matter content (22,18%) . Found greater fraction of fine sand and very fine suspended solids and solid medium sand in the background. As mitigation measures for the process of silting of the reservoir PCH Costa Rica (MS) highlights the orientation of landowners in adopting conservation measures and planting of leguminous species native to the region in symbiosis with nitrogen-fixing bacteria

Projeto elétrico básico de uma subestação industrial típica na classe 15 kV

The electrical substations have the goal to transmit, distribute and change the characteristics of electrical energy transmission networks of dealers to the end user with a high rate of reliability and continuously. For this it’s necessary to accomplish a gathering of datas from the local dealers where will be installed the substation to make a good electric project. This work has the objective to gather all the contents relatives to electric project of substation that are scattered in the literature, in order to organize and develop a basic guide that presents a methodology to dimension electrical equipments that belong to an industrial substation at 15 kV. In addition to elaborate a basic guide, this work aids to specify electrical equipments installed in the substation, bringing information and comparisons to know and determinate the kind of equipments that will be used, in a correct and coherent way with the national and international rules. Ultimately, after determined, got and specified all the equipments that belongs to an industrial substation, the work mention in global manner how to calculate the dimension of substation physical arrangement, determining all the least and required dimensions of each cubicle

Um estudo de novos paradigmas na realização de projetos de instalação elétrica residencial (automação)

Through awareness of new trends of consumption of the population with regard to housing, comfort, entertainment, security and sustainability, it was crafted a work that set out to study and develop the concept of home automation and how it will revolutionize the electrical installation projects and energy savings. A pre-wiring project, taking into account, basically, the installed load, is presented as a basis for comparison. The protocols for communication between intelligent devices in an automation environment, used in the work, are the X-10, LonWorks and UPnP. The home network is studied and divided into subsystems, for a better understanding, which are the lighting, audio, video and multimedia system, security, air conditioning and central vacuum system, and the idea of integrated design and system integrator is introduced, showing the change necessity in the design philosophy of electrical installations. The main means of energy savings in an automated home, such as dimerization, master off and smart meters are presented and, finally, it was concluded that there is a need to structure electrical installation projects more comprehensive with regard to home automation, in order to become more efficient and useful to users

Anteprojeto de um sistema digital de proteção e controle aplicado em uma subestação elétrica industrial

With the growth of the demand on electric energy in the last decades, the urban distribution and transmission systems have experienced a bigger necessity to improve on the substations, the automation procedures and techniques on the operation maneuvers of such systems, in a sense that better attends the quality levels, availability, continuity and operational reliability. In this way, the objective of the present paper is to perform a study of protection and control on an electrical industrial system involving the procedures of digitizing and maneuvers automatism utilizing operational techniques and other pertinent information used in a typical high-voltage Industrial Electrical System. Analysis were made on short-circuits to specify the main components of the 138 [kV] substation, in addition, there were used digital MiCOM relays to make the protection of the present elements. With that, a program was developed to allow the user to monitor the condition of circuit-breakers through a supervision screen being able to simulate some kinds of faults, as well as observing the characteristics of each device. This way, the importance of having a fast and reliable system that ensures the equipment’s protection and the industrial process continuity due to faults on the electrical system is noticeable. It’s important to highlight that all this digitizing was mainly favored by the development of digital technology on the last years, mainly on microelectronics, also with the appearance of supervision gadgets allowing the development of complex systems in supervision and electric energy control

O uso de software para estudo de seletividade e coordenação

The present work aims to prepare a study of selectivity and coordination in an isolated electrical system with the aid of computer software PTW (Power Tools for Windows). Based on appropriate protection standards, on equipment data and the survey of the curves of “time versus current” (Time Current Curve – TCC), may be defined protection settings to leave the system selective, coordinated and properly protected. Definitions of adjustments are made taking into account the data of, so called, thermal curves of the equipment, which take into account the rated current and the supportability of short-circuit current of the equipment and cables involved in the installation in question. For that we use the tools provided by the PTW in which an industrial electrical circuit is simulated, presenting and discussing the results. With that validates the software PTW, taking it as a great tool helper implementation the coordination and selectivity study

Dispositivo de microdescargas em gases na pressão atmosférica

Neste trabalho foi desenvolvido um dispositivo de microdescargas em gases à pressão atmosférica para geração de plasma a fim de ser utilizado no tratamento de superfícies. O trabalho foi baseado em um estudo de iniciação científica que aconteceu em duas etapas. Na introdução apresentam-se as motivações do estudo, o dispositivo desenvolvido na primeira etapa do trabalho bem como os primeiros resultados e propostas de melhorias. Definem-se os objetivos da segunda etapa, que contemplam modificações no dispositivo de descarga e na fonte de alimentação. Em seguida são explanados os métodos utilizados para confecção do dispositivo, construção da fonte de alimentação e circuito de fotodetecção para observar as descargas. Apresenta-se o modelo e configurações dos experimentos, os resultados obtidos são expostos e debatidos brevemente. Colocam-se as conclusões do trabalho e novas propostas de investigação e melhoramentos para o estudo das microdescargas. Seguem-se os agradecimentos aos envolvidos no projeto e, por fim, a bibliografia utilizada

A influência da temperatura nas impedâncias de sequência de condutores utilizados na rede primária de distribuição

Distribution networks are formed by long lines that carry electricity substations to homes and industries. These lines have associated impedance and depending on operating conditions of the network these impedances may vary. This paper provides a detailed analysis of the effects observed in studies of voltage drop, short circuit and electrical losses, when considered the drivers sequence impedances used in primary distribution network at different temperatures. Therefore, it is initially presented a calculation methodology and details the factors that influence the final values. The methodology presented tackles in a practical way the main factors that directly or indirectly influence the values of the impedances as an emblematic example and will be properly dealt with throughout the paper is the effect of temperature on the values of the sequence impedances. More specifically is dealt with the case of XLPE cables protected, by having a higher maximum operating temperature than the operating temperature of the network. The effects observed in the power flow generated when considering the impedance values at both temperatures were analyzed. The impedance drivers tend to increase with increasing temperature. Thus the impedance of the conductor XLPE protected will tend to be greater for the maximum operating temperature for which the operating temperature of the network, resulting in greater voltage drop and higher electrical losses

Caracterização de plasmas a partir do monômero digime através da espectrometria de massa: deposição polimérica

Pós-graduação em Engenharia Mecânica - FEG

epresentação de linhas de transmissão por meio do modelo de bergeron: inclusão do efeito da frequência nos parâmetros longitudinais

Pós-graduação em Engenharia Elétrica - FEIS

Estudo da condutividade elétrica em filmes finos de derivados de politiofeno

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estudo dos efeitos do tamanho e comensurabilidade nas correntes críticas em fitas supercondutoras do tipo II com redes periódicas de pinnings à temperatura finita

Pós-graduação em Ciência e Tecnologia de Materiais - FC