Orientador: Nelson Miguel Teixeira / Resumo: O presente trabalho objetiva a elaboração de um modelo matemático que, através da obtenção de parâmetros elétricos de um motor em regime de trabalho, analise a possibilidade de substituição do mesmo por um de menor potência, obtendo-se economia de energia. Elaborou-se um programa computacional, que proporciona análise da eficiência energética no uso de máquinas elétricas em uma agroindústria canavieira. A linguagem computacional Visual Basic da Microsoft, foi utilizada na elaboração de dois processos para obtenção de modelos matemáticos. Um dos métodos utiliza valores obtidos em catálogos, tais como, rendimento e fator de potência para as condições de 50%, 70% e 100% da potência nominal, que foi denominado Método Porcentagens das Cargas. Através desses valores foram possíveis obter as equações das curvas características dos motores para as condições de cargas mencionadas. O outro método utiliza um programa computacional específico para aquisição de coordenadas reais de imagens digitais, ou seja, obtenção das coordenadas das curvas características dos motores, que foi denominado Método Imagens Digitais. Ambos permitirão obter a regressão das curvas características que servirão para o desenvolvimento do programa de análise do motor. Os dados de entrada são os valores de potência nominal, número de pólos, tensão, rotação nominal e corrente de operação do motor em análise que processados, calculam os valores da potência utilizada, fator de potência, rendimento, rotação, escorregamento e fator de utilização. Caso o fator de utilização seja inferior a 70%, o programa recomenda a troca do motor, simulando seu funcionamento de maneira otimizada para as novas condições de potência. Serão calculados então: corrente de operação, potência nominal, potência utilizada, fator de potência, rendimento, rotação, escorregamento... (Resumo completo, clicar acesso eletrônico abaixo). / Abstract: This work has as main purpose the development of a mathematical model which, through the use of electrical parameter of a motor in working process, analyzes the possibility of replacement of the same one by another with lower power in order to save more energy. A computer program has been elaborated and provides the energetic efficiency of the electric machines in a sugar cane agricultural industry. The computer language Visual Basic of Microsoft has been used in two processes in order to get the mathematical model. One of the methods use values obtained in catalogs such as power output and factors to the conditions of 50%, 70% and 100% of the nominal power that was named Percentage of Charge Method. Through these values to get the equation of characteristic curves of the motors above mentioned. The other method uses a specific computer program by receiving real coordinate of digital images that was named Digital Image Method. Both processes will allow to acquire the regression of characteristic curves that will be useful to develop the program of motor analysis. The entrance data are the nominal power, quantity of poles, tension, nominal rotation e motor operation current in analysis once developed, calculate the value of the power used, power factor, output, rotation, slipping and utilization factor. But in case the utilization factor is less than 70% the plan advises to change motor, simulating its functioning in a optimized way to the new power condition. Then will be evaluate the operation current, nominal power, used power, power factor. It has been taken as a model a motor simulator with 29.6 hp power, tension 440 V, 60 Hz, 4 poles and current operation 16 A, the program shows that the motor is superdimentioned and performs the two methods described as follows... (Complete abstract, click electronic address below). / Doutor

Este trabalho teve como objetivo o desenvolvimento de um mini-motor síncrono trifásico, sem escovas e com ímãs permanentes no rotor, utilizado em aeromodelos. O núcleo do estator, usualmente construído com chapas laminadas, foi obtido a partir do processo de Metalurgia do Pó (M/P). Confeccionaram-se corpos de prova de ferro puro, Fe1%P, Fe2%P, Fe3%P, Fe1%Si, Fe3%Si e Fe50%Ni. Foram analisadas as características físicas dos materiais sinterizados que compreendem as grandezas magnéticas: curvas de histerese, resistividade elétrica. Analisaram-se as grandezas mecânicas: dureza e tensão de escoamento. Com os dados magnéticos obtidos, realizaram-se simulações computacionais de funcionamento, onde se observou o fluxo de entreferro e torque. Efetuaram-se ensaios em núcleos de transformadores para analisar as perdas por correntes parasitas. Os resultados foram comparados também com os do estator de chapas. Foi realizada a construção do núcleo do estator a partir de Fe1%P. O estator do mini-motor foi bobinado e instalado em uma carcaça de um mini-motor existente no comércio, para efetuar testes em bancada de acionamento em correntes variadas, onde pôde ser analisada sua eficiência em comparação com o mini-motor com núcleo do estator de chapas. Foi mostrado que é possível a construção de um motor elétrico com núcleo do estator em bloco único de Fe1%P por processo de Metalurgia do Pó, atingindo 74% da eficiência em relação ao mini-motor com núcleo do estator de chapas. / This study aimed to develop three-phase synchronous motor small, brushless and permanent magnets in the rotor, used in model airplanes. The stator core usually constructed of rolled sheets, was obtained from the powder metallurgy process (M / P). Crafted to pure iron specimens, Fe1% P, Fe 2% P, Fe3% P, Fe1% Si, Fe3% Si and Fe50% Ni. They analyzed the physical characteristics of the sintered materials which comprise the magnetic quantities: hysteresis curves, electrical resistivity. Hardness and yield stress: mechanical magnitudes were analyzed. With the magnetic data, computer simulations were carried out of operation where the flux of airgap observed and torque. Tests were affected in cores of transformers for analyzing eddy current losses. The results were also compared with those of the stator plates. Construction of the stator core from Fe1% P was performed. The mini-motor stator was wound and installed in an enclosure of an existing mini-motor trade, for testing in drive bench in varying currents, which could be analyzed efficiency compared to the mini-motor with stator core plates. It has been shown that the construction of an electric motor with the stator core in a single block P Fe1% by Powder Metallurgy process is possible, reaching 74% efficiency relative to the mini-core motor with stator plates.

This Master’s thesis is dedicated to innovative structural design of the supporting frame rear axle of a small urban utility vehicle. The frame allows you to change the wheel base by sliding rear axle so the car can be used in its short or long version. The main part begins with description of the design solutions and continues with selection of a solution and description of its main parts. The work is finished by description of the current state of production and a list of expected expenses.

O trabalho tem como objetivo abordar e investigar a viabilidade técnica e econômica da proposta de substituição de um motor de corrente continua, por um motor síncrono com imãs permanentes. O passo inicial foi a análise de dados referentes à manutenção preventiva do motor em operação comparado ao motor de indução e o resultado foi que se teria grande vantagens. Foi observado que o mercado oferecia uma solução inovadora, que mudou a trajetória dos estudos. Esta solução é o motor síncrono de imã permanentes, que é um motor brushless de corrente alternada, com dimensões reduzidas para a mesma potência de um motor indução trifásico. As perdas por efeito Joule no rotor que praticamente são as maiores, neste caso são desprezíveis, pois o rotor é equipado internamente com imãs de Terras Raras, o Neodímio Ferro Boro de alta energia, que desta forma minimizam também a temperatura no motor aumentando sua vida útil. Além disso, para aplicações onde se tem a necessidade de controle de torque com velocidades baixas é a melhor solução. Estas e outras qualidades fizeram a diferença na escolha deste motor para a aplicação, onde é necessário o controle de torque com a velocidade baixa. Neste trabalho se descreve todas as etapas do retrofiting, incluindo as comparações do sistema atual com duas propostas, através de simulações no software MATLAB, que demonstraram que as expectativas iniciais foram alcançadas, identificando o motor síncrono de imãs permanentes mais indicado nos dias de hoje para a substituição. / The work had as objective approach and investigate the technical and economic viability of the proposed replacement of a DC motor, by a permanent magnets synchronous motor. The initial step was the analysis of data on preventive maintenance of the motor in operation compared to the induction motor and the result was that it would have great advantages. It was observed that the market offered an innovative solution, which changed the course of the studies. This solution is permanent magnet synchronous motor, which is a brushless AC motor with reduced dimensions at the same power of a three phase induction motor. The Joule losses in the rotor which practically are the biggest. this case are not important, because the rotor is fitted internally with Rare Earths Magnets Neodymium Iron Boron the high energy, which thus also minimize the temperature in the motor increasing its lifetime. Also, for application where there is the need to control torque at low speeds is the best solution. These and other qualities made the difference in the choice of this motor to the application, where it is necessary to control torque with low speed. We describe all stages of Retrofitting, including comparisons of the current system with two proposals, through simulations in MATLAB, which have shown that initial expectations were met, identifying the permanent magnet synchronous motor best suited these days for the replacement.

This master's thesis considers by single-phase asynchronous motor. The first part discuss about construction, principle of operation and basic parameters of this motor type. It also discussed the emergence of torque and torque characteristics of the different types of engines. The second part explains the basic ways of obtaining grip moment including outline the principles of functions particulars constructions types, which is produce in practice. In the third part is minutely analyse single-phase asynchronous motor with auxiliary phase and permanently conect capacitor, including method of assign size of a capacitor. Fourth part section provides the principles of the procedure for calculating basic parameters of the single asynchronous motor with auxiliary phase. At the last part is accomplished a calculation of single-phase asynchronous motor with permanently conect capacitor at auxiliary phase including comparation with already manufacturing motor.

The current processing of electric motor feet and centering collars has been focusing on two main production methods. The production transfer from Germany allowed the introduction of a new enhanced technology. Cutting conditions values, cutting process operating forces , tool life criteria for a maximum productivity and a minimum costs were calculated. Control measurements of the required collar and stator pack concentricity provided the necessary feedback.

This thesis deals with rebuilding of combustion engine powered go-kart for rent to electric powered go-kart. Main goal of work is choose fitting electric engine and electric accessories for reliable working of electric go-kart, put the whole electric drive to rear construction of go-kart and check mechanical part of electric drive.

The goal of this master’s thesis is a construction design of an electric kick bike with the motor builded in the axle of the rear wheel. The thesis consists of theoretical part, which is describing electric kick bikes used today and the possibility of motorization. The next part is a construction design with necessary calculations and formulas.

This Master’s thesis is dedicated to innovative structural design of the supporting frame rear axle of a small urban utility vehicle. The frame allows you to change the wheel base by sliding rear axle so the car can be used in its short or long version. The main part begins with description of the design solutions and continues with selection of a solution and description of its main parts. The work is finished by description of the production the rear axle.

Thesis Methodology of electromobile and hybrid vehicle valuation focuses on these types of vehicles and their specifics in terms of valuation. It attends to the current state of technological advancement in this field, the structural differences from conventional vehicles and the current valuation methods. The aim is to propose a methodology for the valuation of this types of vehicles and its subsequent application to concrete examples.