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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.
71

Design and Implementation of a Novel Control System for Four Quadrant Operation of a Two-Phase Switched Reluctance Motor

Morse, Justin C. 06 January 2004 (has links)
In the emergence of switched reluctance motors to the commercial market, two-phase motors have received relatively little attention. Higher power and industrial applications have focused on the use of three and occasionally four phase machines, while low cost applications demanding only modest performance have largely been the domain of single phase machines. By contrast, while two phase systems have been the subject of occasional studies, they have not been widely applied. Two phase systems represent a compromise between the higher cost but higher performance three phase machines, and the lower cost but lower performance single phase systems. They do not suffer from the same magnitude of peak to peak torque ripple that single phase machines experience due to their wide zero torque arcs. Yet two phase systems keep a relatively low component count in their power-converter designs. The primary drawback to two phase motors is the difficulty of torque production at startup speeds. Although sizably reduced from single phase machines, the zero torque regions in two phase machines can still result in rotor lock unless steps are taken to circumvent them. These steps can include measures such as: placement of permanent magnets or other means to ensure the rotor is positioned outside of these zero torque regions when at rest, mechanically spinning the motor before energizing the phase windings on startup, shaping of the rotor or stator poles to extend the positive torque regions of each phase, or use of the machines mutual inductance with both phases energized to produce enough torque to initiate motion. This project is intended to develop a variable speed controller for a 4:6 two-phase switched reluctance motor. The motor is to operate in all four quadrants, and is to demonstrate self starting capability. The controller is also supposed to produce signals needed to operate the motor with multiple converter designs. Two different converter designs will be built and tested with the converter. One makes use of a single switch and two diodes per phase, the other has one switch and one diode per phase plus a common switch and common diode shared by all phases. There are many possible applications of the system being developed in this project. Any application needing four quadrant operation while still being constrained by low cost requirements would be ideal. Some examples include washing machines, power tools, and low power industrial applications. / Master of Science
72

Velocity sensorless control switched reluctance motors / Commande de vitesse sans capteur du moteur à réluctance variable

Chumacero Polanco, Erik 10 April 2014 (has links)
Dans ce mémoire de thèse, nous présentons la conception, l'analyse de la stabilité, les simulations numériques et aussi les résultats des expérimentes concernant différents contrôleurs de vitesse mécanique du moteur à réluctance variable (MRV).Dans les deux premiers chapitres une brève description de la physique et de la construction du MRV est présenté ainsi que le problème du contrôle d'être abordé, c'est la commande de vitesse sans capteur. Il est aussi présenté l'état de l'art de ce problème et certains des solutions proposées dans d'autres travaux. On propose notre solution et on présente un petit résumé des articles scientifiques qui ont été publiés dans des magazines et des conférences.Dans le chapitre numéro trois est présenté le design du contrôleur adaptatif et sans capteur du MRV. On suppose, dans une première étape que seule la vitesse mécanique est inconnue et la stabilité exponentielle uniforme des erreurs de suivement est obtenue. Dans une deuxième étape, les conditions d'opération sont aggravées et, en plus de la vitesse, les paramètres physiques sont également supposées inconnues, la stabilité asymptotique uniforme est obtenue dans ce cas. L'estimation des paramètres du MRV est garantie grâce à la condition de persistance d'excitation. Cette commande se compose de deux boucles, une boucle interne basée sur un contrôleur de type PI2D qui est particulièrement intéressant parce qu'il est libre de modèle; cette boucle entraîne les variables mécaniques -la position et la vitesse- vers une référence désirée. Une deuxième boucle de contrôle externe prend le courant électrique vers un ' "courant de référence virtuelle" qui est généré sur la base d'une approche de partage de couple. Le contrôleur propose est testé au niveau de simulations numériques qui sont également présentés.Dans le quatrième chapitre, une nouvelle approche de modélisation du MRV est utilisée pour concevoir le contrôleur. Dans ce scénario, on suppose que l'ensemble de l'état et tous les paramètres physiques sont disponibles, cette approche est pensée pour être adapté au contrôleur basé sur observateur, recherche qui est en cours de développement. Le contrôleur est composé de deux boucles, également que celui qui a été mentionné précédemment. Ce contrôleur est sélectionné parce qu'il est approprié pour le contrôle d'équivalence vraie, qui il s'agit de remplacer les «mesures physiques» provenant d'un capteur par les «observations» provenant d'un observateur. La mise en oeuvre numérique est effectuée sur Simulink de Matlab.Enfin, dans le chapitre cinq, les résultats expérimentaux qui ont été effectués pour évaluer la performance des contrôleurs proposés -ce sont les PI2D et adaptatif PI2D pour le modèle simplifie ainsi que le PID pour le nouveau approche de modélisation- sont présentés. Dans la première partie, une brève description de la construction du banc de tests utilisé est présenté ainsi que quelques-unes caractéristiques techniques. Trois différentes profils de vitesse sont imposées à chacun des contrôleurs proposés -ce sont la tangente hyperbolique, la rampe saturée et la référence sinusoïdal- et de bonnes résultats sont obtenus en considérant que la variable contrôlée est la vitesse. Le dernier chapitre correspond aux conclusions de la recherche effectuée ainsi qu'aux travaux futurs. / In this thesis dissertation we present the design, stability analysis, numerical simulations and physical experiments of different controllers designed to drive the mechanical velocity of the switched reluctance motor (SRM). In the First and Second Chapters a brief description of the physics and construction of the SRM is presented, as well as the problem of control to be aboard, that is the velocity sensorless control of motors and the state of the art of this problem. The proposed solution is introduced and a summary of the published papers as well as the contribution are also presented.In the Chapter number three is presented the velocity sensorless and adaptive control of the SRM. It is assumed, in a first stage, that only mechanical velocity is unknown, uniform exponential stability of the errors is achieved in this scenario. In a second stage, conditions are stressed and in addition to the velocity, physical parameters are also assumed unknown, uniform asymptotical stability is achieved in this case and parameters estimation is guaranteed under a persistence of excitation condition. This controller consists of two loops, an internal loop based on a PI2D–type controller which is of particular interest given it is free-model; this loop drives the mechanical variables –that is position and velocity- towards a desired reference. An external control loop takes the electrical current towards a ‘’virtual” current reference which is generated based on a torque share approach. The controller is tested on numerical simulations, which are also presented.In the fourth chapter, a new approach on the modeling of the SRM is utilized to design the controller, in this scenario is assumed that the whole state and all the physical parameters are available, however this approach is thought to be suitable to observer based controller, whose ongoing research is being performed. The controller is composed by two loops, similarly to the one mentioned previously. This controller is selected because it is suitable for certainty equivalence control, that is, to substitute the “measurements” by the “observations” coming from a virtual sensor. Numerical implementation is performed on Simulink of Matlab.Finally, in the Chapter five, the experimental results carried out to evaluate the performance of the proposed controllers are presented, these are the PI2D and the adaptive PI2D controllers for the simplified model and the $PID$ controller for the novel modeling approach. In the first part, a brief description of the construction of the utilized bench is presented as well as the some technical characteristics. Three different velocity profiles were imposed to each of the overmentioned controllers –these are the so called smooth step, the saturated ramp and the sinusoidal reference- and good results, considering that the controlled variable is the velocity, were obtained. The last chapter corresponds to the conclusions of the performed research as well as to the future work.
73

Dimensionnement d'une machine synchro-réluctante à excitation homopolaire par réseaux de perméances / Dimensioning a homopolar synchronous reluctance machine by permeance networks

Belalahy, Christian 14 November 2008 (has links)
Les travaux présentés ici portent sur le dimensionnement et l’étude d’une machine à réluctance variable excitée par un courant continu homopolaire de type``Lyndell´´. De telle structure connaît un regain d’intérêt avec de nouvelles topologies pour des applications spécifiques. Dans le cas des travaux présentés, l’application visée est la conversion d’énergie éolienne avec un stockage inertiel. Cette machine a une bobine d’excitation qui est solidaire du stator et située entre les pôles saillants. Le rotor est massif et comporte deux paires de pôles dont les axes polaires peuvent être parallèles ou perpendiculaires. Le stator possède deux enroulements sur deux demi-stators de machine classique dont l’un est fixe et l’autre orientable manuellement suivant l’axe de rotation du rotor. Cette possibilité d’orientation permet à la machine d’être équipée de l’un ou l’autre des deux types de rotor. Le dimensionnement et l’étude de cette machine sont basés sur le modèle des réseaux de perméances. L’élaboration du modèle, par une subdivision de la structure étudiée en zones à induction homogène, est effectuée à partir de l’analyse des lignes de champ obtenues par la méthode des éléments finis bidimensionnels pour l’ensemble « dent - entrefer - encoche », et les autres parties de la machine (culasse, rotor) sont tridimensionnels. Ces éléments finis constituent également la référence pour valider le modèle développé et pour vérifier le niveau de saturation de la machine. Le modèle par réseaux de réluctance est ensuite utilisé pour dimensionner un prototype, à pôles parallèles ou en quadrature et pour en étudier les performances à vide et en charge. Enfin, le prototype réalisé est étudié pour les deux types de rotor. Les résultats expérimentaux, comparés aux calculs de simulation, montre des concordances très satisfaisantes / The work presented here is devoted to the dimensioning and the study of a switched reluctance machine excited by a homopolar D.C. current of Lyndell type. Such structure knows a renewed interest with new topologies for specific applications. In the case of work had presented, the application concerned for is the wind energy transformation with an inertial storage. The field coil of the machine placed in the stator and is located between the rotor salient poles. The rotor is massive and comprises two pairs of poles. These poles have parallel or perpendicular axes. The stator has two windings placed on two classical half-stators, one of which is fixed and the other is manually adjustable along the axis of rotation of the rotor. This orientation allows the machine to be equipped with one or the other of two types of rotor. The dimensioning and the study of this machine are based on the model of the reluctance network. The development of the model, by a subdivision of the studied structure into homogeneous induction zones, is made from the flux lines obtained by the two-dimensional finite element method for whole tooth-air-gap-slot, and the other parts of the machine (stator breech, rotor) are three-dimensional. The finite element methods also constitute the reference to validate the developed model and check the saturation level of the machine. The reluctance network model is then used for sizing a prototype with the parallel or perpendicular poles and for studying the performances in no load and with load machine. Finally, the realised prototype is studied for both types of rotor. The experimental results compared with the simulation show very satisfactory concordances
74

Design of a reluctance synchronous machine for an electric vehicle with a multi speed gearbox

Vorster, Christiaan Willem 12 1900 (has links)
Thesis (MEng)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Conventional electrical vehicles (EVs) favour mostly permanent magnet machines with single speed gearboxes. This is understandable, the PM machine has a high power density making the electrical machine smaller in size. The PM machine also has a favourable field weakening capability combining this with a single speed gearbox nearly perfectly matches the required traction curve. However the dependency of rare earth metals from China and the environmental issues raised by mining these metals raise concern. Therefore alternatives should be considered. Induction -, switch reluctance - and wound rotor machines are all gaining ground as favourable traction machines to power vehicles. The reluctance synchronous machine (RSM) is known for it’s robustness and high efficiency, however the machine has a limited field-weakening capability. To overcome this short coming a multi gearbox from an internal combustion engine (ICE) is suggested. By combining the RSM and multi speed gearbox it is possible to match the traction curve. There are numerous advantages offered by using this system, especially from an performance and efficiency point of view. However there are also numerous challenges faced by using the suggested powertrain, however the focus of this study is mainly on performance and efficiency of the motor and the powertrain. As a case study a Corsa 140i is used and the design specifications is taken from the ICE. The aim is to design a RSM that meets the specifications of the ICE. The RSM structure is mathematically modelled then optimized using commercial optimization and 2D finite element software. To evaluate the design of the RSM, the motor is then tested. The powertrain is then tested by connecting the motor onto the gearbox of the Corsa and the efficiency of the powertrain is evaluated. The test results it shown that the RSM can be used as a traction motor. There are two motors built one with NO20 and the other with M530-65A lamination steel. Both motors perform well throughout the speed and torque spectrum. The measured efficiency at the rated condition for the motor with the NO20 steel is above 91% and the motor with the M530-65A laminations above 89%. The power train is is tested in 4th and 5th gear. The efficiency of 4th and 5th gear is approximated and the efficiency is above 90% . This high efficiency makes the multi speed gearbox a competitor for the EV power train. / AFRIKAANSE OPSOMMING: Elektrisie voertuie (EVe) het meestal permanent magneet motors met ’n enkel spoed ratkas. Dit is verstaanbaar, die PMS masjien het ’n hoë krag digtigheid wat die masjien kleiner maak in grote. Die PMS masjien het ’n baie goeie vloed veld verswakkings gebied en as dit gekombineer word met ’n enkel spoed ratkas, volg dit die velangde traksie kurwe amper perfek. Die nadeel is dat die PMS motor skaars aard metale nodig het vir die magnete van China af. Die probleem is dat daar baie omgewings probleme gepaard gaan om die metale te myn en China beheer die mark. As gevolg hiervan moet ander tipe motors oorweeg word as traksie motors vir voertuie. Skakel reluktansie, induksie en ’n wikkel rotor motors is almal besig om vordering te maak as traksie motors vir EV’e. Die sinchroon reluktansie motor (RSM) is bekend as ’n robuuste en effektiewe motor. Die probleem met die RSM is dat dit nie ’n goeie vloed veld verswakkings gebied het nie. Om die probleem te oorkom, word ’n veranderlike spoed ratkas van ’n binnebrand engin voorgestel. Deur om die RSM en die veranderlike spoed ratkas as ’n dryfstelsel te gebruik kan die verlangde traksie kurwe ook verkry word. Daar is talle voordele om ’n veranderlike spoed ratkas te gebruik, veral van af ’n draaimoment verrigting en effektiwiteits oogpunt. Daar is ongelukkig ook baie uitdagings wat gepaard gaan as ’n veranderlike spoed ratkas gebruik wil word in die dryfstelsel. Alhoewel daar baie uitdagings is kyk die studie slegs na die draaimoment verrigting en die effektiwiteit van die dryfstelsel. ’n Corsa 140i word as ’n gevallestudie gebruik en die spesifikasies vir die elektrisie motor word vanaf die spesifikasies van die binnebrand engin geneem. Die doel is om ’n motor te ontwerp wat dieselfde spesifikasies het as die binnebrand engin. Die RSM strukstuur word wiskundig gemodelleer en dan geoptimeer deur gebruik te maak van kommersiele optimering en 2D eindige element sagteware. Om die ontwerp te verifieer word die motor getoets. Die dryfstelsel word dan getoets deur om die motor met die raktas te konnekteer. Die draaimoment verrigting en die effektiwiteit word dan ge-evalueer. Twee motors word gebou, een met NO20 laminasies en een met M530-65A laminasies. Beide motors het goeie verrigting deur die spoed en draaimoment gebied. Die gemeete effektiwiteit van die motor met die NO20 laminasies is bo 91% en die motor met die M530-65A laminasies het ’n gemeete effektiwiteit bo 89%. Die toets resultate wys dat die RSM as ’n traksie motor gebruik kan word. Die dryfstelsel word in 4de en 5de rat ge-evalueer. Die effektiwiteit van die ratkas in 4de en 5de word benader en ’n effektiwiteit bo 90% is verkry. Hierdie hoë effektiwiteit maak die veranderlike spoed ratkas ’n lewensvatbare mededinger in die EV dryfstelsel.
75

Optimisation des performances des machines synchro-réluctantes par réseaux de perméances / Performance Optization of Synchronous Reluctance Machine Using Reluctance Network

Raminosoa, Tsarafidy 05 October 2006 (has links)
Du fait de sa robustesse et de son faible coût, la machine synchro-réluctante (MSR) constitue une alternative intéressante à la machine asynchrone. A pertes égales, une MSR bien optimisée offre un couple et par suite un rendement plus élevés. Ainsi, la MSR est très compétitive pour les applications à haute vitesse, à forte puissance ou à haute température. Cette thèse se propose d’optimiser les machines synchro-réluctantes à rotor massif et avec barrières de flux pour produire le maximum de couple avec un facteur de puissance le plus élevé possible. Pour cela, une modélisation originale utilisant des réseaux de perméances non linéaires a été mise au point pour les deux types de MSR. Les modèles proposés sont significativement plus rapides et aussi précis que les modèles par éléments finis. De plus, la réalisation d’un prototype à barrières de flux a permis de les valider expérimentalement. / Because of its robustness and its low cost, the synchronous reluctance motor (SynRM) is an interesting alternative to the induction motor. At equal losses, a correctly optimized SynRM offers a higher torque and then a higher efficiency. Thus, the SynRM is very comptetitive for high speed, high power or high temperature applications. This thesis intends to optimize massive rotor and flux barrier rotor SynRM to produce the maximum torque with the highest possible power factor. For this purpose, an original non linear reluctance network modeling of synchronous reluctance motors with a massive or a flux barrier rotor was developed. The proposed models are significantly faster than the finite element ones and take accurately into account the saturation of all ferromagnetic parts of the motor. The construction of a flux barrier rotor prototype allowed an experimental validation of the modeling approach.
76

Aspectos de projeto, simulação e operação de geradores e motores de relutância chaveados. / Aspects of design, simulation and operation of switched reluctance generators and motors.

Paula, Pedro Pereira de 03 August 2000 (has links)
A finalidade deste trabalho é desenvolver uma contribuição ao projeto de geradores e motores de relutância chaveados. A primeira etapa do projeto consiste no dimensionamento inicial da máquina através de métodos analíticos convencionais [01]para, em seguida, desenvolver o seu refinamento usando o Método dos Elementos Finitos acoplado com as equações de circuitos elétricos. Inicialmente, é apresentada uma abordagem atualizada dos aspectos construtivos e operacionais deste equipamento, comuns aos dois modos de funcionamento, bem como dos aspectos relevantes da metodologia computacional utilizada. Apresentam-se, em seguida, os resultados das simulações conduzidas para a obtenção das características de torque estático, do fluxo concatenado e das indutâncias, em função da posição angular do rotor e da corrente, as suas implicações no projeto e a sua utilização para a definição das condições operacionais dinâmicas a serem simuladas. Em seguida, são apresentados os resultados das simulações em regime permanente e em transitórios operacionais da máquina elétrica funcionando de uma forma integrada com o seu conversor eletrônico dedicado. No fechamento deste trabalho, estes resultados são discutidos e comparados com alguns ensaios realizados. Apresenta-se também os possíveis desdobramentos para a continuidade do projeto deste tipo de equipamento. O enfoque essencial deste trabalho é a máquina elétrica e os seus resultados propiciam também uma orientação para a definição dos requisitos de projeto do conversor eletrônico e do sistema de controle. / This work aims to provide a contribution to the project of switched reluctance generators and motors. The first stage of the project consists of initial dimensioning of the machine through conventional analytical methods[1] followed by its refinement by using the Finite-element Method coupled with circuit equations. An updated approach on the constructive and operational aspects common to both the ways of the equipment, as well as relevant aspects of the computational methodology used are initially presented. Results of simulations carried out to obtain torque characteristics, flux-linkage and inductance, as a function of angular position of rotor and current, their implications in the project and their use to define dynamic operational condition to be simulated are then showed. Sequentially, results of the steady-state and transients operational simulations of the electric machine working in an integrated way with its dedicated electronic converter are presented. In the closing of this work, these results are discussed and compared to some of the tests performed. Related subjects for continuation of the project of this type of equipment are also presented. The main focus of this work is the electric machine and its results also provide an orientation to the definition of requirements to the project of electronic converter and control system.
77

Aspectos de projeto, simulação e operação de geradores e motores de relutância chaveados. / Aspects of design, simulation and operation of switched reluctance generators and motors.

Pedro Pereira de Paula 03 August 2000 (has links)
A finalidade deste trabalho é desenvolver uma contribuição ao projeto de geradores e motores de relutância chaveados. A primeira etapa do projeto consiste no dimensionamento inicial da máquina através de métodos analíticos convencionais [01]para, em seguida, desenvolver o seu refinamento usando o Método dos Elementos Finitos acoplado com as equações de circuitos elétricos. Inicialmente, é apresentada uma abordagem atualizada dos aspectos construtivos e operacionais deste equipamento, comuns aos dois modos de funcionamento, bem como dos aspectos relevantes da metodologia computacional utilizada. Apresentam-se, em seguida, os resultados das simulações conduzidas para a obtenção das características de torque estático, do fluxo concatenado e das indutâncias, em função da posição angular do rotor e da corrente, as suas implicações no projeto e a sua utilização para a definição das condições operacionais dinâmicas a serem simuladas. Em seguida, são apresentados os resultados das simulações em regime permanente e em transitórios operacionais da máquina elétrica funcionando de uma forma integrada com o seu conversor eletrônico dedicado. No fechamento deste trabalho, estes resultados são discutidos e comparados com alguns ensaios realizados. Apresenta-se também os possíveis desdobramentos para a continuidade do projeto deste tipo de equipamento. O enfoque essencial deste trabalho é a máquina elétrica e os seus resultados propiciam também uma orientação para a definição dos requisitos de projeto do conversor eletrônico e do sistema de controle. / This work aims to provide a contribution to the project of switched reluctance generators and motors. The first stage of the project consists of initial dimensioning of the machine through conventional analytical methods[1] followed by its refinement by using the Finite-element Method coupled with circuit equations. An updated approach on the constructive and operational aspects common to both the ways of the equipment, as well as relevant aspects of the computational methodology used are initially presented. Results of simulations carried out to obtain torque characteristics, flux-linkage and inductance, as a function of angular position of rotor and current, their implications in the project and their use to define dynamic operational condition to be simulated are then showed. Sequentially, results of the steady-state and transients operational simulations of the electric machine working in an integrated way with its dedicated electronic converter are presented. In the closing of this work, these results are discussed and compared to some of the tests performed. Related subjects for continuation of the project of this type of equipment are also presented. The main focus of this work is the electric machine and its results also provide an orientation to the definition of requirements to the project of electronic converter and control system.
78

Μελέτη και κατασκευή συστήματος ελέγχου μηχανής Reluctance

Κατσιγιάννης, Αναστάσιος 27 January 2014 (has links)
Η παρούσα διπλωματική εργασία πραγματεύεται την μελέτη και κατασκευή ενός συστήματος ελέγχου για έναν κινητήρα μαγνητικής αντίδρασης (Reluctance). Η εργασία αυτή εκπονήθηκε στο Εργαστήριο Ηλεκτρομηχανικής Μετατροπής Ενέργειας του Τμήματος Ηλεκτρολόγων Μηχανικών της πολυτεχνικής σχολής του Πανεπιστημίου Πατρών. Σκοπός της εργασίας αυτής, είναι η μελέτη και η κατασκευή ενός τριφασικού αντιστροφέα πηγής τάσης, ο οποίος θα επιτρέπει την υλοποίηση βαθμωτού και διανυσματικού ελέγχου για έναν σύγχρονο κινητήρα μαγνητικής αντίδρασης χωρίς έκτυπους πόλους στο στάτη. Ο σύγχρονος κινητήρας μαγνητικής αντίδρασης χωρίς έκτυπους πόλους στο στάτη, όπως και οποιοσδήποτε άλλος κινητήρας μαγνητικής αντίδρασης, βασίζει τη λειτουργία του στη ροπή αντίδρασης, γεγονός από το οποίο προέρχεται και η ονομασία των κινητήρων αυτού του είδους (ReluctanceMotors). Το κύριο χαρακτηριστικό των κινητήρων μαγνητικής αντίδρασης είναι η έλλειψη οποιασδήποτε πηγής διέγερσης στο δρομέα. Τα τελευταία χρόνια έχει αναπτυχθεί έντονο επιστημονικό ενδιαφέρον σχετικά με τη βελτιστοποίηση της κατασκευής των σύγχρονων κινητήρων μαγνητικής αντίδρασης χωρίς έκτυπους πόλους στο στάτη, καθώς και των μεθόδων ελέγχου, που μπορούν να εφαρμοστούν για βελτιστοποίηση της λειτουργίας τους. Αρχικά μελετήθηκαν οι βασικές αρχές λειτουργίας των μηχανών εναλλασσόμενου ρεύματος και η ανάλυση επικεντρώθηκε στο σύγχρονο κινητήρα μαγνητικής αντίδρασης. Μελετήθηκαν τα κατασκευαστικά χαρακτηριστικά του σύγχρονου κινητήρα μαγνητικής αντίδρασης χωρίς έκτυπους πόλους στο στάτη, το μαθηματικό μοντέλο που περιγράφει τη λειτουργία του, συγκρίθηκε με άλλους τύπους κινητήρων εναλλασσόμενου ρεύματος και παρουσιάστηκαν οι μέθοδοι ελέγχου που μπορούν να εφαρμοστούν σε έναν σύγχρονο κινητήρα μαγνητικής αντίδρασης χωρίς έκτυπους πόλους στο στάτη. Επιπλέον μελετήθηκε ο τριφασικός αντιστροφέας πηγής τάσης, ο οποίος είναι απαραίτητος για την οδήγηση ενός σύγχρονου κινητήρα μαγνητικής αντίδρασης, καθώς και διάφορες τεχνικές για την παλμοδότησή του. Τέλος προσομοιώθηκε ο σύγχρονος κινητήρας μαγνητικής αντίδρασης με το πρόγραμμα προσομοίωσης Matlab/Simulink για διάφορες καταστάσεις λειτουργίας του, και ακολούθησε η κατασκευή του τριφασικού αντιστροφέα για την πειραματική διερεύνηση και επιβεβαίωση των αποτελεσμάτων της προσομοίωσης. / The present diploma thesis deals with the design and manufacture of a control system for a Reluctance Motor. This work was developed in the Laboratory of Electromechanical Energy Conversion at the Department of Electrical Engineering and Computer Technology of the School of Engineering in the University of Patras, Greece. The purpose of this thesis is the design and manufacture of a three-phase voltage source inverter for the control of the performance of a Synchronous Reluctance Motor by the implementation of Scalar and Vector control. The operation of Synchronous Reluctance Motor, like any other type of Reluctance Motors, is based on reluctance torque. The main characteristic of Reluctance Motors is that the rotor does not have any field winding. During the last years, a great interest has emerged around the Synchronous Reluctance Motor, which mainly focuses on the optimization of its construction and control. At first, an introduction to the operation principles of the AC motor is done, while the main interest is focused on Synchronous Reluctance Motor. The analysis of Synchronous Reluctance Motor covers many aspects, such as its construction characteristics, its dynamic model, its control strategies, as well as a comparison with other AC motors. Furthermore the three phase inverter is studied and its modulation techniques, since it is used for the driving of the motor. Finally the Synchronous Reluctance Motor is simulated in Matlab/Simulink for some operating conditions, and a three phase voltage source inverter is constructed for the experimental investigation and to see the relationship between the results of the simulation and the experiment.
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Simulação, projeto e teste de um gerador a relutância chaveado trifásico 6 x 4 / Simulation, design and test of a three-phase switched reluctance generator 6 x 4

Coelho, Alexandre 13 June 2011 (has links)
A máquina a relutância chaveada ganhou considerável atenção da comunidade científica com o desenvolvimento da eletrônica de potência e é considerada hoje uma máquina elétrica promissora para algumas aplicações, principalmente aquelas onde há a necessidade de operação em velocidade variável seja como motor ou como gerador. Sendo assim, este trabalho apresenta a dinâmica de funcionamento de uma máquina a relutância chaveada, com uma estrutura 6 x 4, ou seja contendo seis pólos no estator e quatro pólos no rotor, operando no modo gerador. A dinâmica de funcionamento é apresentada e comparada através de resultados experimentais e resultados simulados em ambiente Matlab/Simulink. Os resultados experimentais foram possíveis devido a construção de um protótipo da máquina e da montagem de uma bancada de testes. O projeto desenvolvido para construção do protótipo e da bancada de testes é apresentado neste trabalho. / Switched reluctance machines have received considerable attention from the scientific community due to advances in power electronics, and now is considered a promising electric machine for some applications, especially where variable speed operations are needed for motor or generator. Therefore, this work presents the dynamics of a switched reluctance machine, operating as a generator, with 6 x 4 structure, i.e., six stator poles and four poles in the rotor. Experimental results, which were obtained from a machine prototype installed on a test bench, were compared with Matlab/Simulink computational simulations. The designing aspects for the prototype construction are also discussed in this work.
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Développement d'un modèle de prédimensionnement d'un ensemble alternateur - machine Stirling à pistons libres / Development of a preliminary design of a free piston Stirling engine coupled with a linear electrical alternator

Salquebre, Quentin 21 March 2019 (has links)
Le moteur Stirling a été développé il y’a 200 ans. Cependant son développement n’a jamais connu un grand essor. Le contexte énergétique actuel a relancé l’intérêt porté à ces machines. En effet la possibilité de le faire fonctionner à partir de n’importe quelle source de chaleur externe lui permet d’être associé à des sources d’énergie renouvelable comme l’énergie solaire. Au-delà des avantages écologiques, le développement par W. Beale à la fin des années 1960 d’un moteur Stirling à pistons libres (ou FPSE pour Free Piston Stirling Engine) a ajouté de nouveaux intérêts à un tel moteur. Cette nouvelle architecture permet au moteur de fonctionner sans système d’entrainement des pistons. Dans de telles machines, le mouvement des pistons n’est plus déterminé par la géométrie du système d’entrainement. Ces derniers sont mis en mouvement par les forces de pressions occurrents à l’intérieur du moteur. La dynamique des pistons et la thermodynamique du système sont alors couplées, rendant plus complexe la modélisation complète du système.Cette thèse présente une nouvelle technique de modélisation des machines Stirling à pistons libres, intitulée LHA5V pour Linear Harmonic Analysis 5 Volumes, permettant de coupler la thermodynamique du système et la réponse mécanique des pistons libres. Celle-ci repose alors sur la décomposition du moteur Stirling en cinq sous systèmes ouverts : deux espaces à volume variables, deux échangeurs de chaleur et le régénérateur. Nous supposons que les variables d’état varient périodiquement et le modèle détermine comment celles-ci varient en valeur moyenne, en amplitude et en phase afin de satisfaire les équations de conservation de la masse et de l’énergie. L’aspect innovant du modèle thermique repose sur la prise en compte implicite des pertes inhérentes au fonctionnement. Celles-ci ont en effet un impact direct sur le mouvement des pistons. Par ailleurs cette thèse présente également un modèle de génératrice électrique linéaire pouvant être couplé à la partie thermique. Le modèle électrique repose sur un calcul analytique de la force de poussée du stator sur la partie mobile. Le calcul des flux et du niveau d’induction dans le circuit magnétique est effectué à partir d’un réseau de perméances judicieusement paramétré.Que ce soit pour la modélisation thermique ou la modélisation électrique, chacun des modèles a été conçu pour avoir un temps de calcul faible, tout en restant le plus précis possible sur la prédiction des performances. Ceux-ci ont à chaque fois été confrontés à des données expérimentales, ou à d’autres techniques de modélisation plus fines de façon concluante. / Though the Stirling engine was invented two centuries ago, it has never really grown to a fully marketable level. The current energy context has renewed the interest in this engine. Their ability to work with any external source of heat allow them to be associated with renewable energy such as solar energy. Beyond its ecological benefits, the invention of the free piston Stirling engine by W. Beale at the end of the 1960’s further increased the interest in Stirling engines. This novel structure allows the engine to operate without mechanical interface between pistons, which are driven entirely by the gas or other spring forces. In such engines, the pistons kinematics and the system thermodynamics are intimately coupled, thus increasing the complexity of the complete system computer modelling.This PhD presents an innovative technique to model a free piston Stirling engine that takes into account the coupling between the system thermodynamics and the mechanical response of the free pistons. This technique has been named LHA5V standing for Linear Harmonic Analysis 5 Volumes. It consists in splitting the engine in five open sub-systems: the compression and expansion spaces, the heater, the cooler and the regenerator. We hypothesize that the state variables are periodic, and the model then determines the variations of their mean, amplitude and phase values in order to satisfy the mass and energy conservation equations. This PhD also presents a model for a linear electric alternator, which can be coupled to the power piston. This electrical model is based on an analytical calculation of the thrust between the stator and the magnets. Magnetic flux and induction in the iron are determined by a carefully tuned reluctance network.Both thermal and electrical models have been designed to optimize both computing time and accuracy. The models generated have systematically been compared to experimental data or finite element analysis, with satisfactory results.

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