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

Auxílio na tomada de decisão na compra de uma máquina de usinagem a laser

Decision making is one of the most important factors for growth and future, both from a business, as in people's life and attitudes in the simplest of everyday day. This work aims to assist decision making in buying a laser cut machine, a manufacturer of auto parts and wheels, and later this technique can be considered to acquisition of other equipment. In this case was used the AHP to aid the decision by multiple criteria. First we analyzed the most important criteria of the current machine for the application of the method and were later made the application and sensitivity analysis

Estudo sobre iluminação e banco de capacitores de uma típica indústria metalúrgica

The use of electricity for obtaining light has been quite an issue currently discussed, either through new technologies that are emerging, the quest for greater efficiency, reduced waste and rational use. This work comprises a lighting design applied to a metallurgical based Brazilian Standard 5413 which mentions levels of luminance for interior and, in the case of this work, for a sandblasting booth. Ways to improve the workplace and luminosity presented before the project and also after its implementation are discussed. Technologies are chosen guided by technical calculations according to the illuminance values they want to reach for the environment studied. All pertinent design features are critically analyzed and discussed, and at the end proposals are presented, relating to each other in a comparative framework, so the best solution is applied in a practical way in the enclosure. Results are also presented concerning the maintenance of a bank of capacitors to correct the power factor for the metals studied company

Simulação de contaminação de sedimentos e águas subterrâneas por gasolina e álcool: um estudo de monitoramento de variações das propriedades físico-químicas

Geophysics studies in areas impacted by petroleum derivatives describe abnormalities of both low and high electrical resistivity (the opposite of electrical conductivity), confirmed as contaminant phase by chemical analysis: this contradiction can be explained by degrading processes that naturally occur and create sub products that can change the environment conductivity. Monitoring the variation of the parameters mentioned serves as a comparative basis to the variation in geoelectrical parameters, which identified the correlation between the same contaminant parameters and the difference between their behavior studied apart, as well as its relations with the biodegradation process. The results are applied to the fuel distribution and storage sectors, leading to the diagnosis and monitoring of possible groundwater contamination scenarios, and the knowledge of the area exposure time to the contaminant, besides the better remediation alternative and impacts control. Among some conclusions, the most significant are the decrease in conductivity over time, so as the increase in Eh value in the gasoline contaminated tank, as well as the decrease in the pH value in the second tank with ethanol, which can be attributed to its degradation. Comparing the variations in both tanks, it is evident that Eh, pH and electrical conductivity do not behave temporally in a similar way, although some correlations between Eh and pH can be related.

Modelagem para identificação de indicadores de eficiência energética para edificações e plantas industriais

Pós-graduação em Engenharia Mecânica - FEG

Monitoramento da condição da ferramenta de dressagem usando sinais de vibração e modelos neurais

Pós-graduação em Engenharia Elétrica - FEB

Proposta de metodologia para aplicação de eficiência energética em uma usina hidrelétrica

Pós-graduação em Engenharia Mecânica - FEG

Estudo exploratório sobre o desempenho em aritmética utilizando o soroban como ferramenta auxiliar

Pós-graduação em Matemática em Rede Nacional - IBILCE

Estudo sobre eficiência energética em uma indústria de injeção plástica

The reason of this work is perform a study about using of electrical energy to identify the opportunities through rational use of electrical energy. For that it was necessary perform an analysis of hired energy against consumption. Based in a guide of energy analysis were found the main consumers and verified the main problems, which generate excessive use of electrical energy in a plastic injection factory. It was also analyzed the painting line because there are some thermal equipment that use electrical energy. Based on the data obtained will be proposed ways to reduce the needless consumption and energy use of rationally and efficiently, in addition to re-evaluate the contracted demand based on the new policy of supplying and charging.It were also proposed thermodynamics solutions to reduce the energy consumed in thermal process

Estudo das principais políticas para melhoria da eficiência energética no setor elétrico

This paper aims at comparing the national and international incentive policies in energy efficiency investment and presenting the main trends, measures adopted and economical and environmental results obtained, as well as possible improvements and expansions of these programs. This analysis is justified by the current moment, not only of the Brazilian Power Systems (SEB) but also of the global power systems with the constant increase of demand and depletion of natural resources implying in a need of a better use of them and of the power they generate, which directly affects the losses on the generation, transmission, distribution and consumption of energy, in addition to reducing the impacts on the environment. At last but not least, through this study it was possible to gleam not only at new possible ways for these programs, but also failures and inefficiencies that can be improved in the measures currently being used

Estudo de impacto de ações de eficiência energética em instalações elétricas residenciais

This paper addresses methods of reducing the electric energy consumption on residences by the means of constructive measures and replacement of electric devices. Analyzing their impacts on residential and national level based on data issued by IBGE (Brazilian Institute of Geography and Statistics) and PROCEL (National Program for Electricity Conservation).

Utilização do cavaco de madeira como combustível alternativo para a produção de vapor de água em uma caldeira aquatubular com grelha fixa do tipo PIN HOLE

The steady increase in the price of oil and its derivatives, carbon credits, the concern with the environment combined with the precipitation of rain water and lack of water resources that Brazil has suffered in 2014 caused a migration of participation sources of energy in the Brazilian energy matrix. The hydropower sector suffered big drop at 2013 and is suffering so far, contributing thus to the generation and cogeneration of thermal energy using renewable energy sources such as: sugarcane bagasse, wood chips, rice husks, among others. The selling price of the electricity market reached the level of R$ 807, 00 MWh in January 2014 (Source: ANEEL), heating the Brazilian thermoelectric sector. Although thermoelectric use in bulk water as vaporizing fluid to produce electricity and use in various processes, water reuse plans have become an important factor in these industries. The increased use of biomass has been the bagasse which is allied to the sugarcane sector, strong market in Brazil, and consists basically use the rest of sugar cane, sugarcane industries that would play out. The sugar and ethanol industry is very unstable and only lasts for 6-8 months a year, and the remaining time in the period known as between crop that corresponds to the planting and harvesting of sugarcane and then enter the period of vintage which is the constant cane harvesting and crushing it. This instability of the market and the thermoelectric idle period leads the thermoelectric industries to seek other sources of renewable energy, such as wood chips (pine, Eucalyptus, Orange), rice husk, sorghum among others, to not be dependent on alcohol sector. The present work aims to study the use of wood chips as an alternative biomass for burning a fuel that essentially uses bagasse, the thermoelectric in question consists of two boilers that produce together 350 t / h ... (Complete Abstract click electronic access below)

O papel do gás de petróleo na matriz de energia elétrica brasileira - presente e futuro

This paper presents a study based on literature and examples found on literature of the potential of petroleum gas to be used as a primary source to generate electricity. The steady increase electricity demand in Brazil makes desirable an effective use of all available primary sources, combined with this need the momentum of the country with the discovery of the presalt reserves becomes interesting the use of this gas, often wasted, for generating electricity. The electricity generation in this work is illustrated by the cogeneration in oil refining plants that have the combined cycle thermal operation. The ultimate goal is to provide a text to identify the advantages, disadvantages and trends of this type of generation

Desenvolvimento de um conversor estático PWM para o acionamento de LED’S para iluminação publica

This work deals with the development of a switched-mode power supply circuit based on a Buck topology converter with a Boost Rectifier One-Cycle Control with Power Factor Correction developing, thus, a source of direct current for a module of 50 power LEDs that will be used in a lamp for public street lightning. It is presented, at first, some aspects about the most common technologies used in lamps of public street lightning in Brazil and a comparison with the White LED high power, which is the one that presents itself as the most promising among the existing market. Then it is presented the detailed development of the static converter switched PWM, consisting of a Boost rectifier with power factor correction and methodology of control One-Cycle Control associated with a Buck converter controlled by a PI method that operates as a direct current source . At the end of the simulation results of the circuit through the PSIM software are presented to verify the design behavior

Sistema de gerenciamento de energia para controle de carga/descarga entre baterias de lítio e ultracapacitores, envolvendo sistema de tração elétrica com frenagem regenerativa

Pós-graduação em Engenharia Elétrica - FEIS