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Desenvolvimento de um estator por metalurgia do pó a ser utilizado em um motor universalFernandes, 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.
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Estudo de máquina elétrica de fluxo axial aplicada a sistema de tração automotiva com acoplamento direto e frenagem regenerativaGoltz, Evandro Claiton January 2012 (has links)
Este trabalho descreve o desenvolvimento e caracterização de uma máquina elétrica para aplicação em sistemas de tração automotiva. Compreende o estudo e a análise do perfil de carga e das grandezas eletromagnéticas e eletromecânicas através da construção de modelos analíticos, numéricos e experimentais. Através destes, são propostos critérios para o dimensionamento geométrico e para a escolha dos materiais. A topologia da máquina elétrica possui fluxo axial no entreferro, duplo rotor com ímãs permanentes setoriais, núcleo estator toroidal sem ranhuras e enrolamentos setoriais. Os modelos analíticos tridimensionais para a geometria e o volume dos enrolamentos são uma contribuição relevante em termos científicos. Experimentalmente, a máquina é acionada como gerador síncrono, com um rendimento interno de até 91,75%. Como gerador em regime de frenagem regenerativa obteve-se um rendimento interno de 78,61% no barramento CC. Ao final, utilizando o modelo automotivo de perdas, é feita uma análise em regime permanente do sistema acoplado, visando à caracterização da eficiência energética global do sistema. Os resultados obtidos permitem uma avaliação adequada da máquina no modo de operação proposto. / Este trabalho descreve o desenvolvimento e caracterização de uma máquina elétrica para aplicação em sistemas de tração automotiva. Compreende o estudo e a análise do perfil de carga e das grandezas eletromagnéticas e eletromecânicas através da construção de modelos analíticos, numéricos e experimentais. Através destes, são propostos critérios para o dimensionamento geométrico e para a escolha dos materiais. A topologia da máquina elétrica possui fluxo axial no entreferro, duplo rotor com ímãs permanentes setoriais, núcleo estator toroidal sem ranhuras e enrolamentos setoriais. Os modelos analíticos tridimensionais para a geometria e o volume dos enrolamentos são uma contribuição relevante em termos científicos. Experimentalmente, a máquina é acionada como gerador síncrono, com um rendimento interno de até 91,75%. Como gerador em regime de frenagem regenerativa obteve-se um rendimento interno de 78,61% no barramento CC. Ao final, utilizando o modelo automotivo de perdas, é feita uma análise em regime permanente do sistema acoplado, visando à caracterização da eficiência energética global do sistema. Os resultados obtidos permitem uma avaliação adequada da máquina no modo de operação proposto.
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Controle preditivo não-linear baseado em multimodelos aplicado ao motor de indução / Induction motor non-linear predictive control based on a multimodeling approachFrança, Alex Pereira 08 June 2010 (has links)
Orientador: Edson Bim / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação / Made available in DSpace on 2018-08-16T22:20:50Z (GMT). No. of bitstreams: 1
Franca_AlexPereira_M.pdf: 3058764 bytes, checksum: beb5e6bdbba91505ff0ef14262e6be5c (MD5)
Previous issue date: 2010 / Resumo: Uma abordagem preditiva global-local para o controle de um motor de indução é apresentado nesta tese. O conceito de controle preditivo diz respeito a uma classe de controladores que tem se desenvolvido muito no âmbito do controle de sistemas de conversão de energia nos últimos anos, acompanhando o desenvolvimento da capacidade computacional dos sistemas microprocessados ao longo da última década. A técnica proposta é fundamentada numa lei de controle baseada em uin modelo identificado de um motor de indução. A identificação se dá de maneira experimental a partir da simulação de um motor de indução indiretamente orientado em função do fluxo do rotor, através de um modelo fuzzy do tipo Takagi-Sugeno TS com Funções de Base Ortonormal no consequente das regras.As ações de controle locais são combinadas são combinadas pela ativação das regras do modelo local devido, e a ação de controle global resultante é aplicada ao controle de velocidade do motor de indução. Este método permite ao controlador a inclusão nos parâmetros de controle das não-linearidades e restrições inerentes ao controle do máquinas elétricas / Abstract: A predictive global-local approach technic for induction motor control is presented in this thesis. Predictive control is a very wide class of controllers that have found rather recent applications in the control of electrical machines. Research on this topic has been increased in the last years due to the possibilities of today s microprocessors used for control. The proposed technique is founded on a identified model based predictive control. The identification technique applied in this method is based on the black box modeling of a Indirect Rotor Flux Oriented Induction Motor in stationary reference system through Takagi-Sugeno-TS fuzzy models with orthonormal base functions - OBF - on the rules consequents. Control actions are matched by local activation of the model rule because local and global control action is applied to speed control of an induction motor. This method allows the inclusion in the control parameters of non-linearities and constraints inherent the control of electrical machines / Mestrado / Energia Eletrica / Mestre em Engenharia Elétrica
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Méthode de conception des bobinages des actionneurs électriques adaptés aux nouvelles contraintes de l'avionique / Deisgn method for electrical actuators windings for new aeronautical requirementsMoeneclaey, Julien 23 February 2015 (has links)
Le développement d’avions plus électriques se traduit par une plus grande utilisation d'actionneurs électriques qui remplacent des systèmes hydrauliques et pneumatiques existants ou répondent à de nouveaux besoins. La distribution de l'énergie à bord est basée sur un réseau continu 540V connecté à des convertisseurs électroniques de puissance. Les composants électroniques de puissance à grands gaps (SiC, GaN) améliorent les performances des convertisseurs mais les fronts de tension très raides sont imposés aux bobinages des actionneurs électriques. Chaque front excite un régime transitoire comportant une surtension importante et donc des champs électriques intenses dans l’isolation inter-spires des bobines. Lorsque cette contrainte électrique répétitive dépasse le seuil d'apparition des décharges partielles (PDIV), la durée de vie des couches organiques qui isolent les spires est fortement réduite. L'étude détaillée des décharges partielles (DP) dans l'espace qui sépare les fils émaillés des bobinages permet de situer les zones dans lesquelles les DP se produisent. Elle montre que le thermocollage, avec des surépaisseurs adaptées de thermocolle, permet d'élever le PDIV au-delà des pointes répétitives de tension pour les actionneurs qui fonctionnent dans les parties pressurisées des avions. Des solutions ordonnées de bobinages ont été expérimentées sur des bobines cylindriques imprégnées. Cette analyse montre que l'imprégnation augmente légèrement le PDIV de l'isolation inter-spires dans des proportions qui ne correspondent pas totalement aux caractéristiques intrinsèques du vernis utilisé. Par conséquent, les bobines imprégnées doivent être conçues sur la base des performances de l'isolation primaire du fil émaillé. L’arrangement des spires dans une bobine ordonnée permet de répartir les contraintes et donc de concevoir des bobines qui résistent aux pointes de tension répétitives imposées par l'onduleur aux basses pressions correspondant aux zones non pressurisées d'un avion en vol. Un modèle, basé sur un schéma équivalent HF prenant en considération les deux premières résonances des bobines élémentaires, permet d'analyser la répartition des contraintes entre les bobines connectées en série d'une phase. / The More Electric Aircraft development is reflected by a bigger use of the electrical actuators, which replace the hydraulic or pneumatic system existing or they can also answer to new needs. The energy distribution on board is based on a high voltage continuous bus of 540V connected to electrical power converter. The electric power wide band gap components (SiC, GaN) improve the converters performances but very steep of voltage edge is imposed on the windings of the electric actuators. Each edge excites a transitory regime including an important surge which corresponds to intense electric fields in the inter-turns insulation of coils. When this repetitive electrical constraint exceeds the partial discharges inception voltage (PDIV), the life time of the organic layer between the turns is strongly reduced. The detailed study of the partial discharges (PD) in the area which separate the enamel wire of the windings allows to locate the area where the PD appears. The use of thermo-bonding, with a bonding thickness adapted, allows to raise PDIV beyond the repetitive edge of voltage for the actuators which work in the pressurized parts of the planes. The orderly windings solutions were tested on impregnated cylindrical coils. This analysis shows that the impregnation increases slightly the PDIV from the inter-turns insulation in proportions that do not totally correspond to the intrinsic characteristics of the used varnish. Therefore, the impregnated coils must be conceived on the basis of the primary insulation performance of the enamelled wire. The turn’s arrangement in an orderly coil allows to distribute the constraints and so to conceive the windings which can resist the compulsory repetitive of voltage spikes by the inverter in low pressures corresponding to not pressurized zones in a plane during the flight. A model, based on HF equivalent schema taking in consideration the first two resonances of the elementary coils, allows to analyse the constraints distribution between the coils connected in series of a machine phase.
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Méthodes d’évaluation du risque de décharges partielles dans le bobinage de machines électriques destinées à la traction automobile / Methods for assessing the risk of partial discharges in windings of electrical machines used in electric vehiclesBenmamas, Loucif 30 November 2017 (has links)
Une machine électrique utilisée pour un entraînement à vitesse variable est généralement alimentée par un convertisseur statique dont les composants électroniques de puissance commutent extrêmement rapidement. De ce fait, chaque enroulement statorique de la machine est soumis à des fronts raides de tension dont la répartition sur les différentes spires qui le constituent dépend notamment des capacités parasites entre spires ou entre spires et carcasse. Des zones locales de fort champ électrique apparaissent dans le bobinage conduisant souvent la création d'une activité de décharges partielles. Ce travail de thèse a pour but de fournir des informations quantifiées et précises quant aux risques encourus lorsque divers paramètres liés à l'alimentation de la machine et la topologie du bobinage varient permettant de contribuer à acquérir une expertise vis à vis des problèmes liés à l’apparition de décharges partielles au sein des bobinages, et à en déduire des règles de conception. / Electrical machine used in variable speed drives are usually fed by a converter using fast switching power electronics devices. Thus, each stator winding of the machine is subjected to steep-fronted voltage pulses whose distribution over its various turns depends on the parasitic capacitances between turns or between turns and slot walls. Therefore, local areas of high electric field appear within the coil, often resulting in partial discharges activity. This thesis aims to provide accurate and quantified information regarding partial discharge inception when various parameters related to the machine power supply and winding topology so as to help develop expertise with respect to problems related to partial discharges, as well as to deduce machine design rules in this regard.
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Partial discharges of epoxy-mica-insulation under harmonic distorted voltagesLinde, Thomas, Backhaus, Karsten, Schlegel, Stephan 02 March 2022 (has links)
The increasing propagation of power electronics technologies and the related operational equipment such as inverter-fed drives and solid-state transformers in electrical grids lead to growing harmonic distortion of the
voltage waveform. Harmonics modify the shape of a voltage waveform but also affect the peak voltage despite constant RMS voltage. Resulting from this, it was previously found that harmonics not only have an influence
on the partial discharge patterns and characteristics but also the lifetime of model insulations. The epoxy-mica main wall insulation of rotating electrical machines is partial discharge-resistant to certain extent. Nonetheless,
severe production faults should be detected by partial discharge measurements as they may lead to accelerated ageing. The purpose of this contribution is to investigate the impact of harmonics on the partial discharge
characteristics of the insulation system of rotating electrical machines in general and especially on a test object with an artificial void fault. An assessment of the partial discharge pattern and apparent charge measurement
is given by analyzing the characteristics to harmonic waveform parameters that incoporate peak alteration and shape modification. It is shown that the voltage shape and gradients play a subordinate role compared to the
voltage peak altering effect of harmonics. The effects are more pronounced with the test object with an artificially introduced fault.
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DFIG-BASED SPLIT-SHAFT WIND ENERGY CONVERSION SYSTEMSRasoul Akbari (13157394) 27 July 2022 (has links)
<p>In this research, a Split-Shaft Wind Energy Conversion System (SS-WECS) is investigated</p>
<p>to improve the performance and cost of the system and reduce the wind power</p>
<p>uncertainty influences on the power grid. This system utilizes a lightweight Hydraulic Transmission</p>
<p>System (HTS) instead of the traditional gearbox and uses a Doubly-Fed Induction</p>
<p>Generator (DFIG) instead of a synchronous generator. This type of wind turbine provides</p>
<p>several benefits, including decoupling the shaft speed controls at the turbine and the generator.</p>
<p>Hence, maintaining the generator’s frequency and seeking maximum power point</p>
<p>can be accomplished independently. The frequency control relies on the mechanical torque</p>
<p>adjustment on the hydraulic motor that is coupled with the generator. This research provides</p>
<p>modeling of an SS-WECS to show its dependence on mechanical torque and a control</p>
<p>technique to realize the mechanical torque adjustments utilizing a Doubly-Fed Induction</p>
<p>Generator (DFIG). To this end, a vector control technique is employed, and the generator</p>
<p>electrical torque is controlled to adjust the frequency while the wind turbine dynamics</p>
<p>influence the system operation. The results demonstrate that the generator’s frequency is</p>
<p>maintained under any wind speed experienced at the turbine.</p>
<p>Next, to reduce the size of power converters required for controlling DFIG, this research</p>
<p>introduces a control technique that allows achieving MPPT in a narrow window of generator</p>
<p>speed in an SS-WECS. Consequently, the size of the power converters is reduced</p>
<p>significantly. The proposed configuration is investigated by analytical calculations and simulations</p>
<p>to demonstrate the reduced size of the converter and dynamic performance of the</p>
<p>power generation. Furthermore, a new configuration is proposed to eliminate the Grid-</p>
<p>Side Converter (GSC). This configuration employs only a reduced-size Rotor-Side Converter</p>
<p>(RSC) in tandem with a supercapacitor. This is accomplished by employing the hydraulic</p>
<p>transmission system (HTS) as a continuously variable and shaft decoupling transmission</p>
<p>unit. In this configuration, the speed of the DFIG is controlled by the RSC to regulate the</p>
<p>supercapacitor voltage without GSC. The proposed system is investigated and simulated in</p>
<p>MATLAB Simulink at various wind speeds to validate the results.</p>
<p>Next, to reduce the wind power uncertainty, this research introduces an SS-WECS where the system’s inertia is adjusted to store the energy. Accordingly, a flywheel is mechanically</p>
<p>coupled with the rotor of the DFIG. Employing the HTS in such a configuration allows the</p>
<p>turbine controller to track the point of maximum power (MPPT) while the generator controller</p>
<p>can adjust the generator speed. As a result, the flywheel, which is directly connected</p>
<p>to the shaft of the generator, can be charged and discharged by controlling the generator</p>
<p>speed. In this process, the flywheel energy can be used to modify the electric power generation</p>
<p>of the generator on-demand. This improves the quality of injected power to the</p>
<p>grid. Furthermore, the structure of the flywheel energy storage is simplified by removing</p>
<p>its dedicated motor/generator and the power electronics driver. Two separate supervisory</p>
<p>controllers are developed using fuzzy logic regulators to generate a real-time output power</p>
<p>reference. Furthermore, small-signal models are developed to analyze and improve the MPPT</p>
<p>controller. Extensive simulation results demonstrate the feasibility of such a system and its</p>
<p>improved quality of power generation.</p>
<p>Next, an integrated Hybrid Energy Storage System (HESS) is developed to support the</p>
<p>new DFIG excitation system in the SS-WECS. The goal is to improve the power quality</p>
<p>while significantly reducing the generator excitation power rating and component counts.</p>
<p>Therefore, the rotor excitation circuit is modified to add the storage to its DC link directly.</p>
<p>In this configuration, the output power fluctuation is attenuated solely by utilizing the RSC,</p>
<p>making it self-sufficient from the grid connection. The storage characteristics are identified</p>
<p>based on several system design parameters, including the system inertia, inverter capacity,</p>
<p>and energy storage capacity. The obtained power generation characteristics suggest an energy</p>
<p>storage system as a mix of fast-acting types and a high energy capacity with moderate</p>
<p>acting time. Then, a feedback controller is designed to maintain the charge in the storage</p>
<p>within the required limits. Additionally, an adaptive model-predictive controller is developed</p>
<p>to reduce power generation fluctuations. The proposed system is investigated and simulated</p>
<p>in MATLAB Simulink at various wind speeds to validate the results and demonstrate the</p>
<p>system’s dynamic performance. It is shown that the system’s inertia is critical to damping</p>
<p>the high-frequency oscillations of the wind power fluctuations. Then, an optimization approach</p>
<p>using the Response Surface Method (RSM) is conducted to minimize the annualized</p>
<p>cost of the Hybrid Energy Storage System (HESS); consisting of a flywheel, supercapacitor, and battery. The goal is to smooth out the output power fluctuations by the optimal</p>
<p>size of the HESS. Thus, a 1.5 MW hydraulic wind turbine is simulated, and the HESS is</p>
<p>configured and optimized. The direct connection of the flywheel allows reaching a suitable</p>
<p>level of smoothness at a reasonable cost. The proposed configuration is compared with the</p>
<p>conventional storage, and the results demonstrate that the proposed integrated HESS can</p>
<p>decrease the annualized storage cost by 71 %.</p>
<p>Finally, this research investigates the effects of the reduced-size RSC on the Low Voltage</p>
<p>Ride Through (LVRT) capabilities required from all wind turbines. One of the significant</p>
<p>achievements of an SS-WECS is the reduced size excitation circuit. The grid side converter is</p>
<p>eliminated, and the size of the rotor side converter (RSC) can be safely reduced to a fraction</p>
<p>of a full-size excitation. Therefore, this low-power-rated converter operates at low voltage</p>
<p>and handles the regular operation well. However, the fault conditions may expose conditions</p>
<p>on the converter and push it to its limits. Therefore, four different protection circuits are</p>
<p>employed, and their effects are investigated and compared to evaluate their performance.</p>
<p>These four protection circuits include the active crowbar, active crowbar along a resistorinductor</p>
<p>circuit (C-RL), series dynamic resistor (SDR), and new-bridge fault current limiter</p>
<p>(NBFCL). The wind turbine controllers are also adapted to reduce the impact of the fault</p>
<p>on the power electronic converters. One of the effective methods is to store the excess energy</p>
<p>in the generator’s rotor. Finally, the proposed LVRT strategies are simulated in MATLAB</p>
<p>Simulink to validate the results and demonstrate their effectiveness and functionality.</p>
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Terminal Behavioral Modeling of Electric Machines for Real-time Emulation and System-level AnalysisNazari, Arash 20 September 2022 (has links)
Stability and sustainability of operation of interconnected power converter systems has been an important focus of study in the field of power electronics and power systems. With ever-increasing application of electrical machines by means of electrification of vehicles, airplanes and shipboards, detailed study of the relating dynamics is very important to ensure the proper implementation and stable behavior of the overall system. In this work, the application of the black box approach study of the power converters has been expanded to the electrical machines. Using this modeling method, it is possible of have accurate behavior of electrical and mechanical terminals of the machine without the detailed information about the internal structure of the machine, material characteristics or topology of the machine. Instead, accurate model of electrical and mechanical terminals of the machine are achieved by measuring specific frequency responses of the machine to distinguish dynamic relation of the various electrical and mechanical quantities of the machine. The directly measured frequency responses, are coupled with the dynamics of the source and load in the electrical and mechanical terminals of the machine thus in order to decoupled the described couplings a mathematical process is used that results in decoupling of the controller and drive on the electrical side and the dynamics of the mechanical load and mechanical shaft at the mechanical terminal of the machine. Resulting model is the linear time invariant representation of the electrical machine at a specific operating point. Additionally, this work represents the application of this modeling method for accurate measurement of internal parameters of the machine such as inductances and mechanical inertia and characterization of the mechanical shaft coupler. Resulting unterminated model of the machine is a very important matter of information for system integrators and electrical and mechanical designs related to the application of the machine, to ensure the stable and sustainable operation of the machine. This work for the first time, represents the experimental implementation of this terminal behavioral modeling method for studying electrical machines as well as describes some of the practical limitations of this methodology. By incorporating and integrating a combination of commercially available devices such as frequency response analyzer, Hardware-In-The-Loop (HIL), Power-Hardware-In-The-Loop (PHIL), a test setup has been developed that is capable of control, operate and study arbitrary frame small-signal related measurements required for terminal behavioral study of the electrical machines. Resulting model of the machine that has been extracted from this modeling method is then used to compare in time domain with the real machine in the case of transient change in the mechanical load on the shaft to discover the validity of this modeling procedure. / Master of Science / According to the data from the International Energy Agency, around half of the electricity used globally is consumed by electric motors. Moreover, the growth in the electrical vehicle industry will increase their application even further, hence the development of high-fidelity models of electric machines for real-time emulation, system-level analyses, and stability studies still stands out as an important and needed research focus. New modeling concepts that go beyond the standard industry practice can be used at the design and integration stage to ensure the stable behavior of the overall system. Furthermore, convenient testing and identification pressures can help ensure the long-term operation of the system. Aligned with this trend, this thesis is studying permanent magnet synchronous machines (PMSM) using small-signal terminal-behavioral three-port networks. Having such a behavioral model of the machine available provides many opportunities for system integrators, and even enables an in-situ system observation and stability assessment at both the machine's electrical and mechanical interfaces. This capability can undoubtedly be of high importance in practice, as it is offering new insights into dynamic interactions of the electro-mechanical systems, the governor or turbine control design in ships, aircrafts, electrical vehicles, and even large synchronous machines in power plants. A so-called characterization testbed has been built that combines Hardware-In-The-Loop (HIL) and Power-Hardware-In-The-Loop (PHIL) environments, with sensor-interface boards that are used to properly scale measured signals for machine control. The Frequency-Response-Analyzer is used to sweep the proper electrical or mechanical terminal of the machine by perturbing the proper control signal within the machine controller running in PHIL and reading d-q currents, voltages, torque, and speed variables whose dynamic ratios are then obtained without the need for interrupting the normal operation of the electrical machine. The capability of acquiring such a detailed model of the machine while the machine is in operation is an important benefit of this modeling method, in comparison to the conventional identification methods widely applied in the industry. The resulting model is a linearized time invariant representation of the electrical machine at a specific operating point of interest, and can be used by system integrators to ensure the stability of the system using well known stability assessment methodologies. Furthermore, this modeling strategy has been experimentally verified for the first time on electrical machines, and the resulting model has been compared with the transient behavior of the machine in the presence of a step change in the mechanical load of the machine.
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Modélisation et optimisation d’un alterno-démarreur synchrone à griffes pour l’application « mild-hybrid » / Modeling and optimization of a claw-pole synchronous starter generator for a mild-hybrid applicationDevornique, Geoffrey 16 October 2017 (has links)
Les travaux de recherches menés dans cette thèse concernent la modélisation et l’optimisation de l’alternateur synchrone à griffes utilisé dans les véhicules mild-hybrid. Ce dernier voit son utilisation élargie à la fonction d’assistance de traction au moteur thermique et de récupération d’énergie dans les phases de freinage. La structure spéciale du rotor rend nécessaire l’utilisation de modèles éléments finis 3D pour modéliser finement les effets tridimensionnels. Ces derniers requièrent une utilisation intensive des ressources informatiques (RAM, temps CPU) qu’il est crucial de réduire pour envisager une démarche d’optimisation de dispositifs magnétiques. Dans ce contexte, l’utilisation d’une plateforme de modélisation ouverte Gmsh et GetDP, permettant l’implémentation de géométries et de formulations appropriées, a abouti au développement de modèles précis et suffisamment rapides pour être intégrés dans des algorithmes d’optimisation. L’originalité de cette démarche de modélisation consiste à hybrider une approche numérique (éléments finis 3D) et une approche semi-analytique (réseau de perméances) de sorte que l’usage des éléments finis 3D soit réduit aux zones où le champ magnétique est tridimensionnel. Enfin, le choix d’un algorithme d’optimisation adapté aux modèles numériques (boîte noire à fort coût d’évaluation) a permis de développer un outil de pré-dimensionnement et de dimensionnement des machines synchrones à griffes en vue de l’obtention d’une géométrie optimisée en réponse à un cahier des charges industriel / The research work carried out in this thesis concerns the modeling and optimization of claw-pole synchronous alternator used in mild-hybrid vehicles. The use of this machine is extended to assistit traction engine and energy recovery in the braking phases. The special structure of the rotor makes it necessary to use 3D finite element models to analyse efficiently the three-dimensional effects, which requires an intensive use of computing resources (RAM, CPU time). The latter must be reduced in order to consider an optimization process on such magnetic devices. In this context, the use of a Gmsh and GetDP, open modeling platform, led to the development of precise models, fast enough to be integrated into optimization algorithms. The originality of this modeling approach is based on the hybridization of a numerical approach (3D finite elements) and a semi-analytical approach (permeance network) so that the use of 3D finite elements is reduced to areas where The magnetic field is three-dimensional. Finally, the choice of an optimization algorithm adapted to numerical models (black box with high evaluation cost) allows to develop a pre-design and a design tools for claw-pole synchronous machines in order to obtain an optimized geometry achieving an industrial specification
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Transformação dq não senoidal para máquinas síncronas com imã permanente no rotor / Non-sinusoidal dq transformation for rotor permanent magnet synchronous machinesMonteiro, José Roberto Boffino de Almeida 19 December 2002 (has links)
O presente trabalho apresenta uma transformação dq não senoidal e sua aplicação em máquinas síncronas com ímã permanente na superfície do rotor (MSIP) e forma de onda de FEM não senoidal. O modelo resultante da aplicação dessa transformação permite o controle direto do torque eletromagnético, permitindo reduzir as ondulações do torque produzido nesse tipo de máquina. A redução dessas ondulações em MSIPs não senoidais possibilita que esse tipo de máquina seja empregado em aplicações onde somente MSIPs senoidais, que possuem custo mais elevado, poderiam ser usadas. Simulações e resultados práticos, obtidos pela implementação do sistema de controle vetorial não senoidal desenvolvido, são apresentados no trabalho. Pelos resultados obtidos, pode-se verificar que o método proposto é eficaz na redução das ondulações do torque eletromagnético em MSIPs não senoidais. / This work presents a non-sinusoidal dq transformation and its application in permanent- magnet synchronous machines (PMSM) with a non-sinusoidal back-EMF waveform. The resulting model of the application of such transformation permits direct control of machine electromagnetic torque, which achieves the reduction of torque ripple. The reduction of torque ripple in non-sinusoidal PMSMs makes possible the use of this kind of PMSM instead of sinusoidal PMSMs, which are more expensive. Simulation and practical results, obtained by the implementation of such non-sinusoidal vectorial control system, are shown in this work. Those results show that the method presented is efficacious in the torque ripple reduction in non-sinusoidal PM synchronous machines.
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