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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Metodologia de análise e caracterização de materiais compósitos magnéticos macios aplicados em atuador planar de indução

Mota Neto, João January 2015 (has links)
O trabalho apresenta o desenvolvimento de uma metodologia denominada modelo de núcleo reduzido, aplicada para avaliar o desempenho de máquinas elétricas no que tange a geometria e materiais empregados na fabricação do núcleo completo. Para fins de validação da metodologia utiliza-se um Atuador Planar de Indução Trifásico com dois graus de liberdade, comparando os resultados numéricos e experimentais. Através desta metodologia, pode-se realizar a análise dos fenômenos eletromagnéticos ocorridos no núcleo completo por meio da avaliação de seu modelo reduzido, composto neste caso por 33% do núcleo completo empregado no Atuador Planar de Indução Trifásico. A comprovação da metodologia do modelo de núcleo reduzido ocorreu através da fabricação de uma bancada de testes, composta por uma célula de carga para realizar aquisição da força de propulsão planar, interface de potência e os núcleos reduzidos com seguintes materiais ferromagnéticos: compósitos SMC 1P Somaloy 500®, Ferro resinado e Aço ABNT 1020. Com auxilio da estrutura de testes, validou-se o modelo numérico dos três núcleos reduzidos quanto a força de propulsão planar. Na análise dos dados experimentais e numéricos, o material Ferro resinado apresentou a diferença 14% referente a força de propulsão planar, sendo a maior diferença entre os materiais estudados. Com a convergência dos resultados experimental e numéricos, realiza-se a comparação numérica entre os núcleos reduzidos e completos utilizando-se os três materiais ferromagnéticos. A análise numérica do núcleo reduzido com o material SMC 1P Somaloy 500® apresentou o fator de relação médio da força de propulsão planar de 2,65 em relação ao núcleo completo. O núcleo completo com Aço ABNT 1020 resultou no consumo médio de 56,7Watts para gerar a força de propulsão planar de 1 Newton. Dessa forma, proporciona-se uma ferramenta de maior rapidez para fabricação e avaliação do desempenho de materiais ferromagnéticos utilizados no núcleo completo da máquina elétrica. / This paper presents the development of a methodology denominated low core model applied to evaluate the performance of electrical machines with respect to geometry and materials used in manufacturing of the complete core. For validation purposes of the methodology is used a Planar Three-phase Induction Actuator with two degrees of freedom, comparing the experimental and numerical results. Through this methodology, it is possible to perform the analysis of electromagnetic phenomena occurring in the complete core based evaluation of the reduced model, made in this case with 33% of the full core employed in the Planar Three-phase Induction Actuator. The verification of the reduced core model methodology occurred through the manufacture of a testing bench, which is composed of a load cell to realize the acquisition of the planar propulsion force, potency interface and reduced cores with the following ferromagnetic materials: SMC 1P Somaloy 500® composites, resinated Iron and Steel ABNT 1020. With the help of the test structure, it was validated the numerical model of the three reduced cores regarding to the planar propulsion force. In the analysis of experimental and numerical data, the resinated Iron material showed a 14% difference concerning the strength of the planar propulsion, which is the biggest difference between the materials studied. With the convergence of the experimental and numerical results, a numerical comparison is performed between the reduced and complete cores using the three ferromagnetic materials. The numerical analysis of the reduced core with the SMC 1P Somaloy 500® material showed the average ratio of the planar factor propulsive force of 2.65 when compared with the complete core. The complete core with ABNT 1020 Steel resulted in an average consumption of 56.7 Watts to generate a planar propulsive force of 1 Newton. Thus, it is provided a faster tool for manufacturing and evaluation of ferromagnetic materials performance used in the complete core of the electric machine.
32

On design and analysis of synchronous permanent magnet machines for field-weakening operation in hybrid electric vehicles

Magnussen, Freddy January 2004 (has links)
A regular vehicle of today is equipped with an internal combustion engine that runs on either gasoline or diesel, which are fossil fuels from oil reserves that are millions of years old. In all types of combustion processes carbon dioxide and several other emissions are produced. There are none known technologies of today that can reduce the emissions of carbon dioxide from combustion, but the amount that is produced is mainly dependent on the fuel that is used. Combustion of fossil fuels increases the contamination of carbon dioxide in the atmosphere and diminishes the oil resources. The results are global warming and empty oil reserves within a few decades with the current production tempo, in addition to many other pollution effects that are harmful to the environment. A transition towards a society based on sustainable transportation is therefore urgent. The hydrogen fuel cell powered car with an electric propulsion system has the potential to be the car of the future that possesses the required characteristics of no harmful tailpipe emissions. There are some obstacles in the way for an early commercialisation, including the expensive catalysts used today and the lack of an infrastructure based on hydrogen, though. The hybrid electric vehicle, with both a conventional as well as an electric drivetrain, is a natural candidate for making the transition from the conventional car towards the car of the future. This thesis is focused on the design and analysis of permanent magnet machines for a novel hybrid electric vehicle drive system called the Four Quadrant Transducer. A number of electrical machine aspects are identified, including cores of soft magnetic composites, fractional pitch concentrated windings, core segmentation, novel machine topologies and cost effective production methods. The main objective is to analyse and judge the many unconventional machine aspects of which some may have the potential to improve the performance and reduce the cost of permanent magnet machines. Another objective is to study the effects of the use of fossil fuels and describe them with a new perspective and thereby make one small contribution to the debate about energy issues. Much focus has been spent on the theory of concentrated windings for permanent magnet machines. The potential parasitic effects and methods to improve the torque performance have been described. Other topics that have been given a high priority are material and power loss studies. An important contribution to the understanding of iron losses during field-weakening operation has been presented. A comprehensive use of finite element modeling has been done in the analysis combined with measurements on several laboratory prototypes. The Four Quadrant Transducer drivetrain and its two electrical machines intended for a midsized passenger car has been studied. The gearbox can be of a simple single stage type, which reduces the mechanical complexity and makes the traction performance of the vehicle smooth, without gear changes and drops in power. Simulations on a complete hybrid system show that fuel savings of more than 40% compared to a conventional vehicle can be achieved at citytraffic driving. The savings are modest at highway driving, since the engine is required to operate at high power during such conditions, and the support from the electrical system is negligible. The laboratory prototypes have shown that it is possible to manufacture high performance electrical machines with high material utilization and potential for automated production. The described concepts offer cost effective solutions for future drive systems in automotive and industrial applications. A number of weaknesses with the presented constructions have also been characterized, which should serve as guidelines for creating more optimized machines.
33

Casting and characterization of Fe-(Cr,Mo,Ga)-(P,C,B) soft magnetic bulk metallic glasses

Stoica, Mihai 09 November 2005 (has links) (PDF)
The ferromagnetic bulk metallic glasses (BMGs) started to be investigated only in the last 10 years.They are difficult to cast, but their properties are uniques. The work deals with casting, mechanical and soft magnetic properties of new Fe-based BMGs. Such alloys can be cast directly in samples with various geometries and they can be use as magnetic parts in different devices.
34

On design and analysis of synchronous permanent magnet machines for field-weakening operation in hybrid electric vehicles

Magnussen, Freddy January 2004 (has links)
<p>A regular vehicle of today is equipped with an internal combustion engine that runs on either gasoline or diesel, which are fossil fuels from oil reserves that are millions of years old. In all types of combustion processes carbon dioxide and several other emissions are produced. There are none known technologies of today that can reduce the emissions of carbon dioxide from combustion, but the amount that is produced is mainly dependent on the fuel that is used. Combustion of fossil fuels increases the contamination of carbon dioxide in the atmosphere and diminishes the oil resources. The results are global warming and empty oil reserves within a few decades with the current production tempo, in addition to many other pollution effects that are harmful to the environment. A transition towards a society based on sustainable transportation is therefore urgent. The hydrogen fuel cell powered car with an electric propulsion system has the potential to be the car of the future that possesses the required characteristics of no harmful tailpipe emissions. There are some obstacles in the way for an early commercialisation, including the expensive catalysts used today and the lack of an infrastructure based on hydrogen, though. The hybrid electric vehicle, with both a conventional as well as an electric drivetrain, is a natural candidate for making the transition from the conventional car towards the car of the future. </p><p>This thesis is focused on the design and analysis of permanent magnet machines for a novel hybrid electric vehicle drive system called the Four Quadrant Transducer. A number of electrical machine aspects are identified, including cores of soft magnetic composites, fractional pitch concentrated windings, core segmentation, novel machine topologies and cost effective production methods. The main objective is to analyse and judge the many unconventional machine aspects of which some may have the potential to improve the performance and reduce the cost of permanent magnet machines. Another objective is to study the effects of the use of fossil fuels and describe them with a new perspective and thereby make one small contribution to the debate about energy issues. Much focus has been spent on the theory of concentrated windings for permanent magnet machines. The potential parasitic effects and methods to improve the torque performance have been described. Other topics that have been given a high priority are material and power loss studies. An important contribution to the understanding of iron losses during field-weakening operation has been presented. A comprehensive use of finite element modeling has been done in the analysis combined with measurements on several laboratory prototypes. </p><p>The Four Quadrant Transducer drivetrain and its two electrical machines intended for a midsized passenger car has been studied. The gearbox can be of a simple single stage type, which reduces the mechanical complexity and makes the traction performance of the vehicle smooth, without gear changes and drops in power. Simulations on a complete hybrid system show that fuel savings of more than 40% compared to a conventional vehicle can be achieved at citytraffic driving. The savings are modest at highway driving, since the engine is required to operate at high power during such conditions, and the support from the electrical system is negligible. The laboratory prototypes have shown that it is possible to manufacture high performance electrical machines with high material utilization and potential for automated production. The described concepts offer cost effective solutions for future drive systems in automotive and industrial applications. A number of weaknesses with the presented constructions have also been characterized, which should serve as guidelines for creating more optimized machines. </p>
35

Elaboration et étude des conditions de mise en forme de poudres composites métalliques pour des pièces industrielles à vocation électromagnétiques / Elaboration and shaping of composite particles for electromagnetic industrial pieces

Guicheteau, Rudy 18 March 2015 (has links)
Le développement des moteurs électromagnétiques nécessite des matériaux magnétiques possédant une forte induction à saturation, une perméabilité magnétique importante, ainsi que de faibles pertes magnétiques lorsque le matériau est utilisé à des fréquences allant jusqu’à 20 kHz.Pour réduire ces pertes, le matériau doit alors posséder une résistivité électrique la plus élevée possible. Les composites magnétiques doux ont été développés dans ce contexte, en associant du fer (ou un alliage) à un matériau isolant. Historiquement, ceux-ci étaient présents sous forme de couches laminées, mais des matériaux coeur-écorce se sont développés ces dernières années.Au cours de ces travaux, nous avons développé l’enrobage de particules de fer par un matériau isolant et magnétique : le ferrite NiZn. L’enrobage de ferrite a été réalisé par voie liquide. De cette manière, il a été possible de réaliser un enrobage homogène d’épaisseur contrôlée sur des particules de fer sphériques.L’étude de la mise en forme de ces particules coeur-écorce, par métallurgie des poudres, a montré qu’en frittant le matériau composite à une température supérieure à 580°C, une réaction d’oxydoréduction a lieu entre les deux composés. Cette réaction mène à la formation d’une phase type FexNi1-x et d’une solution solide FeO-FeZnO. Ces deux phases font alors chuter les propriétés magnétiques du matériau final.Pour éviter cette réaction d’oxydoréduction, nous avons montré qu’il est possible d’ajouter une barrière de diffusion : la silice, ou bien de fritter le matériau à l’aide de techniques type FAST. De cette manière, nous avons obtenu un matériau possédant des pertes magnétiques comparables à celles de poudres industrielles mais avec une perméabilité magnétique supérieure. / Magnetic materials with high saturation induction, high magnetic permeability and low magnetic losses, are necessary for the development of electromagnetic motors used at frequencies up to 20 kHz.The electric resistivity of these materials must be as high as possible to reduce iron losses. To increase the resistivity of ferromagnetic materials, soft magnetic composites (SMC) were developed combining a ferromagnetic material with an insulating one. Firstly, laminated steel sheets were developed but during the last years core-shell materials were investigated.In this work, we have studied the coating of iron particles by an insulating and a magnetic material: NiZn ferrite. These coatings were deposited by an aqueous solution to obtain a homogenous coating with a controlled thickness on spherical iron particles.A study of composite shaping by powder metallurgy shows a redox reaction between ferrite and iron at a sintering temperature above 580°C. This reaction leads to the formation of a FexNi1-x and a FeO-FeZnO solid solution. These two phases deteriorate the magnetic properties of the final material.To avoid this redox reaction, we have shown that a silica layer can be used as a diffusion barrier. Another solution is to sinter the composite with a Field Assisted Sintering Technique (FAST) as Spark Plasma Sintering. A material with properties similar to industrial material and with a superior magnetic permeability was obtained with Spark Plasma Sintering
36

Estudo de um atuador planar de indução

Baggio Filho, Nolvi Francisco January 2012 (has links)
O presente trabalho trata do estudo, análise, construção e teste de uma nova configuração para um atuador planar. O dispositivo, que apresenta uma movimentação sobre o plano com dois graus de liberdade a partir de um único dispositivo de tração, é formado por um carro, também chamado de primário, que apresenta dois enrolamentos trifásicos independentes, ortogonais entre si, montados em um núcleo ranhurado de material compósito magneticamente macio de grão isolado; e por um estator, também chamado de secundário, formado por uma chapa de alumínio plana montada sobre um núcleo ferromagnético igualmente plano, formando a área de trabalho ou de movimentação do primário. Através de um acionamento trifásico, os enrolamentos produzem campos magnéticos viajantes, fazendo com que correntes elétricas induzidas apareçam nos materiais eletricamente condutores do secundário. A interação entre os campos magnéticos e as correntes induzidas proporciona o aparecimento de uma força planar de propulsão na direção do campo magnético viajante, responsável pelo deslocamento do primário sobre a área de trabalho, definida pelo secundário. O atuador apresenta uma distribuição espacial da densidade de fluxo magnético em toda a sua estrutura. Este trabalho preocupa-se em analisar analítica, numérica e experimentalmente os fenômenos eletromagnéticos envolvidos, tanto em regime estático como dinâmico. O emprego de duas configurações para o secundário, utilizados separadamente, é investigado: no caso 1 é montado um núcleo de material ferromagnético sobre o qual é colocada uma chapa de alumínio; já no caso 2, é retirado o alumínio do conjunto, mantendo-se o mesmo material ferromagnético, a saber, aço maciço 1020. Uma análise estática e dinâmica, a partir do método dos elementos finitos tornou possível a verificação da densidade de fluxo magnético no entreferro e da distribuição da densidade de corrente elétrica induzidas nos materiais do secundário em função da excitação trifásica dos enrolamentos do primário, bem como a obtenção dos seus efeitos sobre a força planar de propulsão, considerando as duas configurações propostas para o estator. Além disso, pode-se comparar esses resultados, direta ou indiretamente, como os resultados analíticos e experimentais obtidos. Esses resultados apontam que existem diferenças significativas na utilização das duas configurações, indicando que o caso 1, quando utilizado de maneira adequada no sistema, produz uma melhor resposta de força em função da excitação elétrica. / The present work presents the study, analysis, implementation and test of a new type of planar actuator, the induction planar actuator with orthogonal windings. The device, which presents movement over the plan with two degrees of freedom from a unique traction device, is formed by a car, also called primary, which presents two three-phase independent winding, orthogonal among each other, assembled on a slotted core made of grain insulated soft magnetic composite material and by a stator, also called secondary, formed by an aluminum plate assembled over a plan ferromagnetic core equally plan, forming a work area or of primary movement. Through the three-phase operation drive, the windings produce traveling magnetic fields, having the electric induced current to appear at the electrically conductor materials of the secondary. The interaction between the magnetic fields and the induced currents provides the appearance of a planar traction force towards the traveling magnetic field, responsible for the displacement of the primary over the work area, defined by the secondary. The actuator presents magnetic flow density spatial distribution in all its structure. This paper is concerned about analyzing analytically, numerically and experimentally the phenomena involved as in steady as dynamic state. The employment of two settings to the secondary used separately is argued: in case 1 a ferromagnetic core is assembled over which is placed an aluminum plate; in case 2 the aluminum is taken off the setting, maintaining the same ferromagnetic material (steel 1020). Dynamic and statics analysis, from the finite elements method, made the verification of the magnetic flux density possible in the air gap and the distribution of the electric current density induced on the material of the secondary due to the three-phase excitation of the winding of the primary, as well as the obtainment of its effects over the planar traction force, regarding the two settings proposed for the stator. Besides, it’s possible to compare these results, direct or indirectly as analytical and experimental results obtained. These results point the there are meaningful differences at both settings, indicating that case 1, when used adequately in the system, produces better force response due to the electric excitation.
37

Desenvolvimento de um rotor por metalurgia do pó a ser utilizado em um motor universal

Cas, Roberto Luis Ribeiro Da January 2015 (has links)
O objetivo principal deste trabalho foi o desenvolvimento de um núcleo do rotor de um motor universal a partir dos processos da metalurgia do pó (M/P). O rotor desta máquina, cujo núcleo é originalmente fabricado em chapas laminadas, foi substituído por um rotor com núcleo em bloco maciço, mantendo-se as demais partes como eixo e escovas. A partir de simulações no software FEMM e dados existentes referentes ao desempenho de ligas metálicas sinterizadas como Fe-P, Fe-Si e Fe-Ni, foi selecionado o Fe1%P, que apresentou os melhores resultados para a aplicação na máquina elétrica em questão. Foram feitas simulações relacionadas às características eletromagnéticas e a partir dos resultados obtidos puderam-se fazer comparações entre um rotor convencional, fabricado com núcleo de chapas laminadas e o rotor com o núcleo maciço fabricado utilizando-se a metalurgia do pó. As etapas de fabricação consistem em mistura da liga, compactação, sinterização e forma final através de eletroerosão. A máquina foi montada utilizando a estrutura de um motor de furadeira manual comercial, mantendo-se todas as partes da máquina original com exceção do núcleo do rotor, e posteriormente foi testada em bancada, comparativamente a uma máquina convencional para análise dos resultados. Foi possível a substituição do rotor oriundo de placas laminadas por um rotor oriundo de metalurgia do pó. Os resultados dos ensaios com a máquina fabricada comprovaram que a liga Fe1%P é, comparativamente ao núcleo de chapas convencional, tecnicamente inferior para a fabricação de motores universais. Utilizando a liga Fe1%P seu rendimento foi de 7% contra 27% do motor convencional assim como torque e demais parâmetros ficaram abaixo do motor padrão. / The main objective of this work was the development of a rotor core of a universal motor from the processes of powder metallurgy (M/P). The rotor of this machine, whose core is originally manufactured in laminated plates, was replaced by a rotor core with solid block, keeping the other parts like shaft and brushes. From the software FEMM simulations and existing data regarding the performance of sintered alloys such as Fe-P, Fe-Si and Fe-Ni, was selected Fe1%P, which showed the best results for application in electric machine in question. Simulations were made related to the electromagnetic characteristics and from the results of comparisons could be made between a conventional rotor, made of rolled core and the solid core rotor is manufactured using powder metallurgy. The manufacturing steps comprise of mixing the alloy, compacting, sintering and final form by electro erosion. The machine structure was assembled using a hand drill motor trade, keeping all parts of the original machine except the rotor core, and thereafter the machine was tested on bench, compared to a conventional machine to analyze the results. It was possible to replace the rotor coming from a rotor laminated plates derived from powder metallurgy. The results of the tests made with the machine shown that the alloy Fe1% P is compared to a conventional core plates, technically inferior to manufacture universal motors. Using the league Fe1%P its yield was 7% versus 27% of the conventional engine as well as torque and other parameters were below the standard engine.
38

Desenvolvimento de um estator por metalurgia do pó a ser utilizado em um motor universal

Fernandes, Fernando Martins January 2015 (has links)
Este estudo identifica as vantagens do uso de um estator fabricado usando a tecnologia da metalurgia do pó, identificando suas vantagens e desvantagens. O motor elétrico utilizado é um motor do tipo universal originalmente o estator desta máquina, possui o núcleo fabricado em chapas laminadas, este foi substituído por um estator com núcleo em bloco maciço, mantendo-se as demais partes do motor originais, ou seja, nestes testes o rotor bobinado continuará a utilizar chapas laminadas e escovas originais. Motores elétricos foram desenvolvidos no início do século XIX e desde então vem sendo utilizado em larga escala com mudanças pouco significativas na sua forma construtiva, materiais e processo de fabricação. Neste trabalho o principal objetivo foi o desenvolvimento de um núcleo do estator para motor universal a partir dos processos da metalurgia do pó (M/P). Simulações com o software FEMM identificaram o comportamento de várias ligas (Fe-P, Fe-Si e Fe-Ni). Após análise dos dados da simulação foi selecionado o Fe1%P, por ter apresentado os melhores resultados para a aplicação na máquina elétrica em questão. As simulações permitiram comparações dos parâmetros eletromagnéticos e torque, entre estatores utilizando chapas de silício do motor original e estatores de núcleo maciço com dados das ligas experimentadas fabricadas através da metalurgia do pó. A fabricação destes núcleos consiste nas misturas da liga, compactação utilizando matriz para formato desejado, sinterização e acabamentos através de usinagem e eletroerosão. Foi utilizada uma furadeira manual comercial, testada em bancada para levantamento detalhado a fim de caracterizar as propriedades que definem a eficiência do equipamento com o estator original. Os mesmos testes foram conduzidos apenas substituindo o estator, agora de núcleo maciço. Processo de fabricação através da metalurgia do pó permite um menor consumo de material e energia, sendo este um processo muito mais eficiente quando comparado ao processo de fabricação das chapas laminadas de ferro silício. / This study will identify the advantages of using a fabricated stator using the technology of powder metallurgy, identifying its advantages and disadvantages. The electric motor used is a universal type motor, originally the stator core of this machine are made of laminated plates, this was replaced by a stator core with solid block , keeping the remaining parts of the original machine, ie these tests the wound rotor continued to use rolled sheet and original brushes. Electric motors were developed in the early of 19th century, and has since been used in large scale with little significant changes in its constructive form, materials and manufacturing process. This work has as main goal the development of a stator core for universal motor from the processes of powder metallurgy (M/P). Simulations with the FEMM software identified the behavior of various alloys (Fe-P, Fe -Si and Fe-Ni) .After data analysis of the simulation was selected Fe1%P, for having presented the best results for the application in the electric machine in question. The computer simulations of electromagnetic parameters and comparisons torque between stator plates using the original silicon motor stators and solid core of data experienced alloys manufactured by powder metallurgy. The manufacture of these core constitutes mix league, using compression matrix to desired shape, sintering and finishing by machining and EDM. Trade manual drill was used, tested on bench for detailed study to characterize the properties that define the efficiency of the equipment to the original stator. The same tests were conducted just by replacing the stator, now solid core. Manufacturing process by powder metallurgy allow less consumption of material and energy, this is a much more efficient process compared to the process of manufacturing the laminated silicon iron sheets.
39

Metodologia de análise e caracterização de materiais compósitos magnéticos macios aplicados em atuador planar de indução

Mota Neto, João January 2015 (has links)
O trabalho apresenta o desenvolvimento de uma metodologia denominada modelo de núcleo reduzido, aplicada para avaliar o desempenho de máquinas elétricas no que tange a geometria e materiais empregados na fabricação do núcleo completo. Para fins de validação da metodologia utiliza-se um Atuador Planar de Indução Trifásico com dois graus de liberdade, comparando os resultados numéricos e experimentais. Através desta metodologia, pode-se realizar a análise dos fenômenos eletromagnéticos ocorridos no núcleo completo por meio da avaliação de seu modelo reduzido, composto neste caso por 33% do núcleo completo empregado no Atuador Planar de Indução Trifásico. A comprovação da metodologia do modelo de núcleo reduzido ocorreu através da fabricação de uma bancada de testes, composta por uma célula de carga para realizar aquisição da força de propulsão planar, interface de potência e os núcleos reduzidos com seguintes materiais ferromagnéticos: compósitos SMC 1P Somaloy 500®, Ferro resinado e Aço ABNT 1020. Com auxilio da estrutura de testes, validou-se o modelo numérico dos três núcleos reduzidos quanto a força de propulsão planar. Na análise dos dados experimentais e numéricos, o material Ferro resinado apresentou a diferença 14% referente a força de propulsão planar, sendo a maior diferença entre os materiais estudados. Com a convergência dos resultados experimental e numéricos, realiza-se a comparação numérica entre os núcleos reduzidos e completos utilizando-se os três materiais ferromagnéticos. A análise numérica do núcleo reduzido com o material SMC 1P Somaloy 500® apresentou o fator de relação médio da força de propulsão planar de 2,65 em relação ao núcleo completo. O núcleo completo com Aço ABNT 1020 resultou no consumo médio de 56,7Watts para gerar a força de propulsão planar de 1 Newton. Dessa forma, proporciona-se uma ferramenta de maior rapidez para fabricação e avaliação do desempenho de materiais ferromagnéticos utilizados no núcleo completo da máquina elétrica. / This paper presents the development of a methodology denominated low core model applied to evaluate the performance of electrical machines with respect to geometry and materials used in manufacturing of the complete core. For validation purposes of the methodology is used a Planar Three-phase Induction Actuator with two degrees of freedom, comparing the experimental and numerical results. Through this methodology, it is possible to perform the analysis of electromagnetic phenomena occurring in the complete core based evaluation of the reduced model, made in this case with 33% of the full core employed in the Planar Three-phase Induction Actuator. The verification of the reduced core model methodology occurred through the manufacture of a testing bench, which is composed of a load cell to realize the acquisition of the planar propulsion force, potency interface and reduced cores with the following ferromagnetic materials: SMC 1P Somaloy 500® composites, resinated Iron and Steel ABNT 1020. With the help of the test structure, it was validated the numerical model of the three reduced cores regarding to the planar propulsion force. In the analysis of experimental and numerical data, the resinated Iron material showed a 14% difference concerning the strength of the planar propulsion, which is the biggest difference between the materials studied. With the convergence of the experimental and numerical results, a numerical comparison is performed between the reduced and complete cores using the three ferromagnetic materials. The numerical analysis of the reduced core with the SMC 1P Somaloy 500® material showed the average ratio of the planar factor propulsive force of 2.65 when compared with the complete core. The complete core with ABNT 1020 Steel resulted in an average consumption of 56.7 Watts to generate a planar propulsive force of 1 Newton. Thus, it is provided a faster tool for manufacturing and evaluation of ferromagnetic materials performance used in the complete core of the electric machine.
40

Estudo de um atuador planar de indução

Baggio Filho, Nolvi Francisco January 2012 (has links)
O presente trabalho trata do estudo, análise, construção e teste de uma nova configuração para um atuador planar. O dispositivo, que apresenta uma movimentação sobre o plano com dois graus de liberdade a partir de um único dispositivo de tração, é formado por um carro, também chamado de primário, que apresenta dois enrolamentos trifásicos independentes, ortogonais entre si, montados em um núcleo ranhurado de material compósito magneticamente macio de grão isolado; e por um estator, também chamado de secundário, formado por uma chapa de alumínio plana montada sobre um núcleo ferromagnético igualmente plano, formando a área de trabalho ou de movimentação do primário. Através de um acionamento trifásico, os enrolamentos produzem campos magnéticos viajantes, fazendo com que correntes elétricas induzidas apareçam nos materiais eletricamente condutores do secundário. A interação entre os campos magnéticos e as correntes induzidas proporciona o aparecimento de uma força planar de propulsão na direção do campo magnético viajante, responsável pelo deslocamento do primário sobre a área de trabalho, definida pelo secundário. O atuador apresenta uma distribuição espacial da densidade de fluxo magnético em toda a sua estrutura. Este trabalho preocupa-se em analisar analítica, numérica e experimentalmente os fenômenos eletromagnéticos envolvidos, tanto em regime estático como dinâmico. O emprego de duas configurações para o secundário, utilizados separadamente, é investigado: no caso 1 é montado um núcleo de material ferromagnético sobre o qual é colocada uma chapa de alumínio; já no caso 2, é retirado o alumínio do conjunto, mantendo-se o mesmo material ferromagnético, a saber, aço maciço 1020. Uma análise estática e dinâmica, a partir do método dos elementos finitos tornou possível a verificação da densidade de fluxo magnético no entreferro e da distribuição da densidade de corrente elétrica induzidas nos materiais do secundário em função da excitação trifásica dos enrolamentos do primário, bem como a obtenção dos seus efeitos sobre a força planar de propulsão, considerando as duas configurações propostas para o estator. Além disso, pode-se comparar esses resultados, direta ou indiretamente, como os resultados analíticos e experimentais obtidos. Esses resultados apontam que existem diferenças significativas na utilização das duas configurações, indicando que o caso 1, quando utilizado de maneira adequada no sistema, produz uma melhor resposta de força em função da excitação elétrica. / The present work presents the study, analysis, implementation and test of a new type of planar actuator, the induction planar actuator with orthogonal windings. The device, which presents movement over the plan with two degrees of freedom from a unique traction device, is formed by a car, also called primary, which presents two three-phase independent winding, orthogonal among each other, assembled on a slotted core made of grain insulated soft magnetic composite material and by a stator, also called secondary, formed by an aluminum plate assembled over a plan ferromagnetic core equally plan, forming a work area or of primary movement. Through the three-phase operation drive, the windings produce traveling magnetic fields, having the electric induced current to appear at the electrically conductor materials of the secondary. The interaction between the magnetic fields and the induced currents provides the appearance of a planar traction force towards the traveling magnetic field, responsible for the displacement of the primary over the work area, defined by the secondary. The actuator presents magnetic flow density spatial distribution in all its structure. This paper is concerned about analyzing analytically, numerically and experimentally the phenomena involved as in steady as dynamic state. The employment of two settings to the secondary used separately is argued: in case 1 a ferromagnetic core is assembled over which is placed an aluminum plate; in case 2 the aluminum is taken off the setting, maintaining the same ferromagnetic material (steel 1020). Dynamic and statics analysis, from the finite elements method, made the verification of the magnetic flux density possible in the air gap and the distribution of the electric current density induced on the material of the secondary due to the three-phase excitation of the winding of the primary, as well as the obtainment of its effects over the planar traction force, regarding the two settings proposed for the stator. Besides, it’s possible to compare these results, direct or indirectly as analytical and experimental results obtained. These results point the there are meaningful differences at both settings, indicating that case 1, when used adequately in the system, produces better force response due to the electric excitation.

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