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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.
1

Design of high frequency operating mechatronic systems : tools and methods of characterization of electromagnetic couplings between electromechanic converters and power electronics converters / Conception d’ensembles mécatroniques à haute fréquence de fonctionnement : outils et méthodes de caractérisation des couplages électromagnétiques entre convertisseur électromécanique et électronique de puissance

Ramos Chavez, Jose Ioav 21 November 2016 (has links)
De l’avion plus électrique, en passant par l’hybridation de véhicules automobiles et jusqu’aux implants cardiaques d’assistance circulatoire, la compacité est devenue le graal de l’électrotechnique embarquée moderne. En effet, la densité de puissance des systèmes électromécaniques ne cesse de s’accroitre. Ainsi, pour répondre aux besoins de forte intégration, les convertisseurs en électronique de puissance trouvent un vecteur de développement dans l’augmentation de leur température et des fréquences de fonctionnement mais aussi dans la réduction des temps de commutation des interrupteurs, leur permettant de réduire leurs pertes thermiques et ainsi, de réduire leurs besoins en refroidissement. Les moteurs et générateurs électriques évoluent avec des topologies aussi diverses qu’innovantes pour répondre aux besoins d’intégration, robustesse et sureté de fonctionnement. Particulièrement, les bobinages des moteurs sont les premiers éléments sur le front de bataille. Au sein du bobinage s’effectuent les échanges entre moteur et convertisseur. L’augmentation des contraintes fréquentielles et transitoires sous forme de fronts de courant et tension issus des ensembles d’électronique de puissance constituent des défis en termes de compatibilité électromagnétique (CEM) pour les systèmes embarqués. Le travail présenté ici est le fruit d’une étroite collaboration entre la société NOVATEM et le laboratoire Génie de Production de l’ENIT de Tarbes au travers d’un financement CIFRE, en association avec la plateforme Labceem de l’IUT de Tarbes. Il propose d’apporter des modèles prédictifs permettant de déterminer les conséquences de ces contraintes d’intégration dans les systèmes mécatroniques de puissance dès les premières étapes de leur conception. Les perturbations conduites dont la source HF est au sein des interrupteurs de puissance du convertisseur, sont façonnées par les impédances caractérisant le chemin de couplage dont le moteur fait partie intégrante. Ce travail vise à élaborer des méthodes et outils pour contribuer à l’étude prédictive de la compatibilité électromagnétique (CEM) des ensembles mécatroniques en essayant de couvrir une plage de fréquence allant de 0 à 300 MHz. Dans une première partie, un état de l’art est détaillé afin de délimiter le contexte et les frontières de l’étude. Puis, un deuxième chapitre porte sur la modélisation analytique de bobinages concentrés de moteurs électriques. Les modèles analytiques établis permettent de déterminer les paramètres de réseaux de circuits pour effectuer des simulations dans le domaine temporel et harmonique. Contrairement aux modèles comportementaux de moteurs répandus dans la littérature, les modèles ici synthétisés prennent en compte les paramètres physiques des bobinages. Ils donnent la possibilité à l’utilisateur de paramétrer les architectures de bobinages concentrés en changeant des paramètres tels que la géométrie des bobines, les matériaux d’isolation ou encore la perméabilité des culasses. Un troisième chapitre, détaille l’établissement d’une méthode rationnelle d’extraction numérique de paramètres fonctionnels et parasites des PCB multicouches de puissance. Cette méthode, de par la prise en compte de paramètres physiques, s’inscrit dans une logique générique et prédictive. Finalement, dans le dernier chapitre, les outils et méthodes précédemment établis sont appliqués à l’étude d’un système réel de motorisation de véhicule électrique développé par la société partenaire Novatem. Le caractère physique et prédictif de ces outils vise à permettre l’expérimentation virtuelle sur l’ensemble moteur-convertisseur sans la nécessité de prototypes. Ce dernier chapitre illustre l’intérêt d’une approche physique en modélisation pour la compatibilité électromagnétique de systèmes mécatroniques. / From the more electrically operated aircraft, to the hybridization of motor vehicles, all the way to electromechanic cardiac implants, compactness has become the holy grail of modern embedded electrical engineering. Indeed, the power-to-weight ratio demands for electromechanical systems has greatly increased. To meet these high integration needs, power electronic converters find a vector of development by increasing their temperature and operating frequencies but also by reducing the switching time of power switches, thus enabling them to reduce their power losses and thereby reducing their cooling requirements. Electric motors and generators operate with various innovative topologies that meet integration, robustness and reliability needs. Motor windings, particularly, are the first motor components on the battle front. It is at the heart of the winding that occur the exchanges between motor and converter. In terms of electromagnetic compatibility (EMC) for embedded systems, the increased frequency and transient stresses in the form of current and voltage edges from the power electronic assemblies are considered steep challenges. The work presented herein is the result of a close cooperation between the company Novatem and the laboratory Génie de Production of ENIT de Tarbes, through CIFRE funding, in combination with the Labceem platform of IUT of Tarbes. Its aim is to develop predictive models that will serve to determine the consequences of such integration constraints in power mechatronic systems that are in the early stages of design. Conducted disturbances whose HF source is located at the inverter power switches are shaped by the impedances characterizing the coupling path of which the electrical machine is an integral part. This work proposes to develop methods and tools to support the predictive study of electromagnetic compatibility (EMC) of mechatronic assemblies, by attempting to cover a modeling frequency range that goes from 0 to 300 MHz’s. In the first chapter of this work, a literature review is detailed for the definition of the context and boundaries of the study. A second chapter focuses on the analytical modeling of concentrated windings in electric motors. The analytical models that are established allow determination of circuit networks settings to perform time- and frequency- domain simulations. Unlike the widespread behavioral models of electrical machine in the literature, the models that are synthesized here take into account the physical parameters of the coils. The user of such models is offered the opportunity to account for the different winding architectures, by changing core parameters such as geometry, insulation materials or permeability. A third chapter describes the establishment of a rational method for extraction of functional and parasitic parameters in multilayer Power PCBs. This method being of a generic and predictive logic aims to account for physical parameters. Finally, in the last chapter, the previously established tools and methods are applied to the study of a real electric vehicle drive system developed by the company Novatem. The physical and predictive value of these tools allows for execution of virtual experimentations on the motorconverter assembly without the need for prototypes. This chapter illustrates the value of a physical approach to modeling the electromagnetic compatibility of mechatronic systems.
2

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.
3

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>
4

Modeling of a PMSynRel stator with concentrated windings using FEM and non-linear reluctance networks

Pablos Rabano, Alejandro January 2013 (has links)
Permanent magnets synchronous reluctance (PMSynRel) motors are attractive due to their high torque density and because a lower quantity of permanent magnets is necessary in comparison with other permanent magnet machines. This thesis deals with the analysis of PMSynRel machines using a finite element method (FEM) and reluctance networks. First, a PMSynRel machine model is built in order to carry out simulations using a finite element method package. The effect of different design parameters such as the combination of the number of poles and slots, the number of flux barriers or the number of magnets can be studied since the implementation provides the possibility to change those variables. Next, a reluctance networks model, aimed to enable lower computation times than corresponding finite element models, is implemented for analysing the flux density distributions along the air gap of the machine disregarding the magnetic influence of the rotor. Finally, the results are compared with FEM simulations. It is concluded that the agreement reached is satisfactory in most of the cases analysed.
5

Design of a Permanent-Magnet Synchronous Machine with Non-Overlapping Concentrated Windings for the Shell Eco Marathon Urban Prototype

Martínez, Daniel January 2012 (has links)
This thesis deals with the design of a permanent-magnet synchronous inner rotor motor for an in-wheel application for the Shell Eco Marathon Urban concept vehicle. First of all, concepts related to permanent magnet motors are studied. Likewise, different features of permanent magnet motors are qualitatively evaluated in order to choose the most suitable. A radial flux motor is selected based on its solid, economic and acceptable characteristics. Next, a detailed study of concentrated windings is carried out. Through this investigation, undesirable configurations of pole and slot numbers due to unbalanced magnetic pull or a low fundamental winding factor will be avoided and how to determine the different winding layouts for different pole and slots configuration will be explained. As well, based on this study, and the magnetic and electric behavior of the machine, an analytical model is created. This model calculates the optimum size and characteristics of a machine in order to obtain lightweight design. After that, the design of a program based on a finite element method that simulates different situations for the machine is accomplished, dealing with the difficulties that entails the concentrated windings. Finally, through the use of this program, the machine calculated by the analytical model is analyzed, specially regarding that it does not surpass some important margin in order not to be demagnetized or not to surpass the maximum phase voltage supplied by the batteries.
6

Dimensionnement vibro-acoustique des machines synchrones à aimants permanents pour la traction ferroviaire : Règles de conception silencieuse / Vibro-acoustic design of permanent magnets synchronous machines for railways application : Low-noise design rules

Fakam Tchakoue, Mathias 07 March 2014 (has links)
Cette thèse de doctorat s'inscrit dans un projet pour le développement du transport ferroviaire piloté par la société ALSTOM Transport. Il répond aux prévisions de quadruplement des déplacements interurbains et régionaux en France à l'horizon 2020 en respectant les contraintes environnementales très sévères, dont les normes restrictives du niveau de bruit émis par les trains. Une réduction importante du bruit émis par le moteur est donc nécessaire. Notre mission dans ce projet a été de développer un outil capable de prédire le bruit d'origine électromagnétique produit par les moteurs synchrones à aimants permanents, équipés d'un bobinage distribué ou concentré, et alimentés par des tensions MLI. Pour cela, un modèle multi-physique a été développé.Un couplage numérique - analytique a été mis en place pour calculer les forces magnétiques dans l'entrefer. La perméance globale d'entrefer et les inductances synchrones sont ainsi calculées grâce à des simulations éléments finis en statique, et très rapides. Un niveau de précision et de rapidité de résolution inégalé est obtenu pour le calcul des forces magnétiques. L'alimentation MLI, la perméabilité des clavettes, la saillance du rotor et l'asymétrie des dents du stator sont pris en compte. La rapidité de l'outil permet un couplage avec un superviseur d'optimisation. Deux prototypes ont été dimensionnés et fabriqués dans le but de valider le modèle multi-physique / This thesis is part of a project for the development of rail transportation piloted by ALSTOM TRANSPORT. It meets the forecasts of fourfold increase of the interurban and regional travels in France before 2020, by respecting very severe environmental requirements, among which the restrictive standards of noise level emitted by trains. An important reduction of the noise radiated by motors is required. Our mission in this project was to develop a tool capable of predicting the electromagnetic noise produced by permanent magnet synchronous motors equipped with distributed or concentrated windings, and fed by a PWM converter. For that purpose, a multi-physics model was developed.A numerical - analytical coupling was set up to calculate the airgap magnetic pressures. Global airgap permeance and synchronous inductances are thus calculated thanks to statics finite element simulations. An unequalled level of precision and speed of resolution is obtained for the computation of airgap magnetic pressures. The PWM supply, the wedge permeability, the rotor shape and the asymmetry of stator teeth are taken into account. The quickness of the resolution allows coupling our tool with an optimization supervisor. Two prototypes were designed and built in order to validate the multi-physics model
7

Contributions à l’étude de machines multi-enroulements pour l’aéronautique : machine synchrone à aimants permanents pour la tolérance aux défauts : machine asynchrone pour la traction / Contributions to the study of multi-winding machines for aeronautic : Permanent Magnet synchronous Motor for fault tolerant applications : Asynchronous motor for Taxiing

Velly, Nicolas 06 April 2011 (has links)
Le projet d'avion électrique vise à remplacer les vecteurs énergétiques que sont les fluides hydrauliques et l'air comprimé par le courant électrique et d'obtenir en conséquence une diminution significative de la consommation en carburant Dans cette thèse, nous proposons deux solutions : la première dans un souci d'accroitre la disponibilités des actionneurs électriques et la seconde pour la traction au sol (taxiage d'avion). Dans la première étude, nous nous plaçons dans le cadre d'un actionneur pour lequel il est demandé une redondance électrique. Ceci peut être le cas d'un actionneur de mode « normal », redondé par un actionneur de type secours, mais où les fiabilités cumulées ne sont pas suffisantes, et où la partie électrique et la commande du système dit normal est redondé. Nous proposons une topologie de moteur synchrone à aimants permanents à bobinage à plots à deux étoiles découplées magnétiquement et à courant de court-circuit limité. Pour les machines à plots, nous avons établi un modèle semi analytique dans le but de prédire l'amplitude de la résultante des forces radiales agissant sur le rotor de cette machine en cas de fonctionnement en modes sain et dégradé. Nous avons établi le modèle de cette machine en vue de la commande et nous avons validé expérimentalement ce principe de conception sur un prototype dimensionné au laboratoire et réalisé par une société du groupe SAFRAN. Dans la seconde étude, nous avons investigué sur l'utilisation de moteurs multi-enroulements permettant de répondre au mieux à un cahier des charges exigeant pour une application de traction d'aéronefs: le « green taxiing ». Le principe est de permettre de faire varier le coefficient de couple d'un moteur de manière à optimiser la masse du moteur mais aussi les contraintes sur le convertisseur qui l'alimente permettant d'atteindre de larges plages de vitesse. Le modèle en vue de l'alimentation a été développé et validé par une comparaison à une résolution par éléments finis en magnétodynamique / The more electrical aircraft project aims at replacing most of current power generation sources by electrical ones. Consequently this replacement might generate a significant decrease of the fuel consumption. Through this thesis we determine two electrical solutions allowing on the one hand the increase of disponibility level of the actuators and on the other handthe aircraft taxiing by electrical means. We firstly focused on electrical actuators that require electrical redundancy. A first mean to achieve this redundancy is to use two actuators. Nevertheless this solution is not relevant under the reliability constraint because the global failure rate is increased. A double star permanent magnet synchronous motor with concentrated winding is proposed in which a special care was taken to the short circuit current limitation and the magnetic decoupling between the two star winding. We established a semi-analytic model for this kind of motors to predict the amplitude of the resultant of the radial forces acting on the rotor of the machine when operating under normal and faulty operation. We established the model of the machine in order to determine the command strategy. We experimentally validated all of the design principles mentioned above through a prototype designed in the laboratory and built by one of the SAFRAN group company. We secondly investigated on the way to apply the multi winding principles to a brand new project linked to the aircraft taxiing called “green taxiing”. The goal is to obtain a motor topology that allows operating on a wide speed range thanks to the command strategy and the change of its torque coefficient. We established the model of the machine and we compared the results given by this ingenious model to the results given by a finite element resolution using a transient magnetic application
8

Design and Analysis of a Fractional-Slot Concentrated-Wound PM-Assisted Reluctance Motor / Konstruktion och analys av en permanent magnetiserade synkronreluktans motor med koncentrerad lindning

Marino, Luigi January 2015 (has links)
The aim of this master thesis is to design and analyse a FSCW PMaSynRM (Permanent Magnet assisted Synchronous Reluctance Motor) for industrial applications. The design process includes analytical calculations (initial design and PM amount minimization) and nite element method (FEM) based design optimization. An overcompensated design is proved to be advantageous for a 10-pole reluctance motor. A comparative analysis with other rotor topologies was made, where motor performance, temperature e ects and production costs are taken into account. Detailed curves which describe eciency, power factor and current with respect to ambient temperature are studied for the proposed motor designs at di erent working points. The demagnetization risk is also taken into account and the safe working temperature ranges have been dened for all the considered motors. The results show that the initial motor design with 10 poles/12 slots PMaSynRM with NdFeB magnets has poor performance in terms of eciency and power factor, with huge amount of PM inserted. This is mainly due to the lack of reluctance torque for this relatively higher number of poles solution. Moreover, it has been found in literature and conrmed in this investigation that this negative e ect for the 10-pole motor is amplied due to the presence of the concentrated winding. Indeed, it is shown by simulations that the motor performance is improved by employing 8 poles/12 slots PMaSynRM conguration with a relatively lower NdFeB magnet amount, thanks to the improved rotor anisotropy. The 10 poles/12 slots interior permanent magnet (IPM) and surface mounted permanent magnet (SMPM) topologies present higher performance due to the e ective utilization of PM, mainly or completely producing the torque. Hence, IPM and SMPM do not su er the lack of anisotropy. / Syftet med detta examensarbete ar att utforma och analysera en FSCW PMaSynRM (Permanent Magnet assisted Synchronous Reluctance Motor) for industriella applikationer. Designprocessen omfattar analytiska berakningar (ursprungliga konstruktion och PM belopp minimering) och nita elementmetoden (FEM) baserad design optimering. En overkompenserad design visat sig vara fordelaktigt for en 10-polig reluktansmotor. En jamforande analys med andra rotor topologier gjordes, dar motor prestanda, temperature ekter och produktionskostnader beaktas. Detaljerade kurvor som beskriver e ektivitet, e ektfaktor och strom med avseende pa omgivningstemperatur studeras for de foreslagna motorn for vid olika arbetspunkter. Den avmagnetisering risken ocksa beaktas och sakerhetstemperaturomraden har denierats for alla ansag motorerna. Resultaten visar att den initiala motordesign med 10-polig/12 spar PMaSynRM med NdFeB magneter har daliga e ektivitet och e ektfaktor, med enorma mangder PM insatt. Detta ar framst pa grund av bristen pa reluktansvridmomentet for denna relativt hogre poltal losning. Dessutom har man funnit i litteraturen och bekraftat i denna unders okning att denna negativa e ekt for 10-polig motorn forstarks pa grund av narvaron av den koncentrerade lindningen. Faktum ar att det framgar av simuleringar att motorprestanda forbattras med en 8-polig/12 spar PMaSynRM konguration med en relativt lagre NdFeB magnet belopp, tack vare den forbattrade rotor anisotropi. Den 10-polig/12 spar interior permanentmagnet (IPM) och ytmonterade permanent magnet (SMPM) topologier presentera hogre prestanda tack vare ett e ektivt utnyttjande av PM och deras produktion vridmoment, huvudsakligen eller helt anfortrotts PM effekten.

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