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

Analysis and Control Aspects of a PMSynRel Drive in a Hybrid Electric Vehicle Application

Zhao, Shuang January 2013 (has links)
This thesis deals withmodeling and control of an electric drive equipped with a permanentmagnet assisted synchronous reluctance (PMSynRel) machine for a plug-in hybrid electric vehicle application. In the first part of the thesis, a special use of the PMSynRel machine in consideration, known as an integrated charger concept, is investigated. The integrated charger feature allows using the PMSynRel machine as a part of the vehicle’s on-board charging system when charging the battery from the grid. A finite-element based analysis is performed providing important insights into the machine operation during the charging process. Dynamic models are developed that facilitate the controller development and the estimation of the efficiency during charging. In the second part of the thesis, position sensorless control of the PMSynRel drive when applied in an automotive application is considered and analyzed thoroughly. First, a fundamental-excitation based rotor-position estimation technique is investigated. The study shows that the impact of current dynamics on the resulting torque dynamics has to be considered in some very demanding applications. Second, focus is put on signalinjection based sensorless control methods. Impacts of nonlinearities, such as magnetic saturation, cross-saturation and inductance spatial harmonics, on sensorless control performance are investigated and methods to improve the sensorless control quality are summarized and presented. An approach to determine the feasible region for operating sensorless at low-speeds without directly measuring the differential inductances is proposed. For the PMSynRel drive in consideration, the achievable maximum torque is limited when operating sensorless following the maximum-torque-per-ampere (MTPA) current reference trajectory at low-speeds. An optimization approach is therefore proposed which extends the output torque when operating sensorless while still maintaining a relatively high efficiency. To initialize the sensorless control correctly from standstill, the impact of the saturated magnetic bridges in the rotor is also investigated. Finally, torsional drive-train oscillations and active damping schemes are considered. An off-vehicle setup for implementing and evaluating different active damping schemes is proposed. Of particular interest for sensorless operation in automotive applications, the impact of slow speed estimation on the possibility to achieve good active damping control is investigated and a design approach that allows the implementation of an active damping scheme using estimated speed is suggested. / <p>QC 20140114</p>
32

Contributions à l’étude des machines à reluctance variable pour application alterno-démarreur automobile / Contributions to the study of Switched reluctance machine for automotive integrated starter-alternator application

Zaharia, Mihai Valentin 15 December 2016 (has links)
Ce travail de recherche est réalisé dans le cadre d'une collaboration internationale entre l'Université Technique de Cluj-Napoca en Roumanie et l'Ecole Centrale de Lille en France. Cette thèse a comme premier objectif, de réduire l’ondulation de couple d’une machine triphasée 6/8 à réluctance variable grâce aux paramètres de contrôle dans le mode de fonctionnement moteur et générateur. Par conséquent, un modèle analytique a été développé et mis en œuvre dans un environnement de calcul numérique. Un outil d'optimisation permettant de trouver les meilleurs paramètres de contrôle a été utilisé. Toutefois, le processus d’optimisation est très lent.En conséquence, une stratégie pour réduire le temps du processus d'optimisation sans abaisser la précision des résultats est proposée. Une stratégie de ‘mapping’ est utilisée entre un modèle grossier mais rapide et un modèle fin mais lent. Un travail est mené sur le choix du modèle grossier, dans le cadre d’un modèle fournissant des valeurs en fonction du temps. Deux stratégies de ‘mapping’ ont été utilisées dans cette thèse : l’‘Output Space Mapping Proportional’(OSMP) et le Manifold Mapping (MM). Ces deux stratégies sont utilisées pour déterminer les paramètres de contrôle optimaux. Le problème d’optimisation est ensuite complété en ajoutant des variables géométriques au processus d’optimisation du contrôle. Les outils développés sont ensuite utilisés dans le cadre du dimensionnement par optimisation d’un alterno-démarreur automobile. Finalement, des expériences et des essais sur un prototype de Machine à RV sont menés afin de valider les résultats du processus d'optimisation en mode moteur et générateur. / The switched reluctance machine has a simple construction making it cheaper in execution but one of the drawbacks of this machine is the torque ripple. This thesis had as first target, the usage of an optimization tool to calculate the best control parameters to correct this major drawback in motor and generator operation modes. Hence, an analytical model that takes into account the machine geometry and that is able to be simulated in both operation modes by adjusting the commutation angles was provided and implemented in a calculation environment. The second target of this work is to investigate a method to reduce the optimization time without lowering the accuracy of the results. The strategy used in the optimization process is known in literature as the space mapping technique, more precisely for this thesis output space mapping proportional and manifold mapping were studied. After testing them on a mathematical model it was possible to continue the investigation on defining the optimal control parameters of a three-phases 6/8 SR machine prototype, being able that further to use this strategy in a much complicated process, i.e. defining the right geometry and control of a SR machine to be used in automotive integrated starter alternator systems. The final target of the thesis was to conduct experiments and tests on the existing prototype in order to partially validate the results of the optimization process.
33

Controlador PI FUZZY aplicado ao controle direto de potência do gerador de relutância variável de 12/8 conectado à rede elétrica

Catata, Elmer Osman Hancco January 2016 (has links)
Orientador: Prof. Dr. José Luis Azcue Puma / Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Engenharia Elétrica, 2016. / Este trabalho apresenta o controle direto de potencia do gerador de relutancia variavel de 12/8 utilizando o controlador fuzzy PI auto-ajustavel e o controle vetorial do inversor conectado à rede eletrica. Inicialmente são estudados os principios de operação da maquina e a topologia do conversor eletronico de potencia que sera utilizado para aciona-lo. Usando o software de simulaçãoMatlab/Simulink é implementado o modelo da maquina de relutancia variavel utilizando as curvas caracteristicas, de corrente e torque, que foram extraídas utilizando dados experimentais. Utilizando o modelo da maquina é projetado o controlador de velocidade para sua operação no modo motor. Tambem sera projetado o controlador de potência PI utilizando o modelo estimado do sistema de conversão de energia eólica. A partir dos ganhos do controlador PI é projetado o controlador fuzzy PI autoajustavel com o objetivo de melhorar a resposta em regime permanente da potencia controlada. A potencia gerada pelo gerador de relutancia variavel é injetada à rede eletrica, atraves do controle independente das potencias ativa e reativa, para este proposito é utilizado um conversor trifasico de dois níveis. Na parte experimental deste trabalho foi implementado o controle de corrente por histerese para maquina operando no modo motor, posteriormente foi implementado o controle de corrente e controle da tens~ao no barramento CC para a máquina operando no modo gerador. Os resultados de simulação e experimentais se mostraram coerentes validando os controladores propostos. / This work presents the direct power control of the switched reluctance generator of 12/8 using the self-tuning fuzzy PI controller and the vector control for inverter connected to the grid. Initially, the machine's operating principles and the topology of the power electronics converter used to drive this machine are studied. The model of switched reluctance machine is implemented in Matlab/Simulink simulation software using the characteristic curves of current and torque extracted using experimental data. Using the machine's model, It is designed the speed controller for its operation in motor mode. Also, the PI controller is designed for the power control loop based on the estimation of the wind energy conversion system. Using the gains of the PI controller, It is designed the self-tuning fuzzy PI controller, in order to improve the steady state response of the power control loop. The power generated by the switched reluctance generator is injected into the power grid through the independent control of active and reactive power, for this purpose is used a three-phase two level converter. In the experimental part of this work was implemented the hysteresis current control for machine operating in motor mode, also, It was implemented the current and DC bus voltage control for the machine operating in generator mode. The simulation and experimental results were proved consistent and these results validate the proposed controllers.
34

Estudo do gerador de relutância variável 12/8 conectado à rede elétrica aplicado em sistemas de geração eólica

Oliveira, André Luiz de January 2017 (has links)
Orientador: Prof. Dr. Alfeu Joãozinho Sguarezi Filho / Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Engenharia Elétrica, 2017. / Neste trabalho é estudado o gerador de relutância variável 12/8 aplicado em sistemas de geração eólica. Para a conexão do gerador com a rede elétrica será empregado o conversor em ponte assimétrico que compartilha o barramento de corrente contínua com um inversor. O conversor assimétrico tem a função de controlar a tensão no elo de corrente contínua e emprega controladores PIs para este fim. Já, o inversor conectado à rede elétrica controla as potências injetadas na rede por meio da técnica de controle orientado por tensão empregando controladores PIs. Analisou-se também as condições da máquina em termos de indução magnética através de simulações computacionais, pelo Método dos Elementos Finitos, com intuito de verificar e estimar os níveis de indução garantindo que a operação do controle atue de fato em condição de não saturação da máquina. Resultados das simulações de operação do gerador conectado à rede elétrica trifásica e dos níveis de indução magnética são apresentados para validar a proposta. / This academic work examines the switched reluctance generator 12/8 applied in wind power generation systems. A asymmetric bridge converter shares the DC link with an inverter that allows generator connection to the power grid. The asymmetric half bridge converter has the function of controlling the voltage of the DC link and uses PI controllers for this purpose. Already, the inverter connected to the grid controls the power injected into the grid across voltage oriented controle by employing PIs voltage controllers. It was also analyzed the machine conditions in terms of magnetic induction through computational simulations, by the Finite Element Method, in order to verify and estimate the induction levels, ensuring that the operation of the control actually acts in the condition of non-saturation of the machine. Results of the operation simulations of the generator connected to the three-phase electric grid and the magnetic induction levels are presented to validate the proposal
35

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

Alexandre Coelho 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.
36

Contribution to multi-physical studies of small synchronous-reluctance machine for automotive equipment / Contribution à l'étude multiphysique de la machine synchro-réluctante pour application automobile

Rasid, Mohd Azri Hizami 11 February 2016 (has links)
Dans une application d’équipement automobile, la conception optimale d’un actionneur nécessite la prise en compte simultané des différents phénomènes physiques ; tant qu’en termes de performances attendues ainsi que les contraintes à respectées. Ces physiques comprennent la performance électromagnétique / électromécanique, comportement thermique et le comportement vibro-acoustique. En prenant en compte le coût et la faisabilité en matières de fabrications, la machine synchro-réluctante (Syncrel) à rotor segmenté a été démontré intéressante pour une application avec des fortes contraintes d’encombrement et thermique. Cette étude a donc pour objective d’évaluer la capacité de la machine Syncrel dans ces différents physiques et démontre les interactions entre eux, qui peuvent affecter les performances de la machine en fonctionnement. Des modèles multi-physiques ont été développés et validés en utilisant une machine prototype conçu précédemment pour un actionneur d’embrayage électrique. En se servant des modèles validés, différents critères de performances des différentes topologies de rotor de la machine Syncrel ont été aussi comparés. A l’issue de l’étude, les modèles électromagnétiques, électromécaniques, thermiques et vibro-acoustiques valides sont à nos dispositions pour être utilisés dans la conception de machine Syncrel en future. La machine Syncrel avec rotor segmenté a été démontrée capable pour être utilisé dans l'application de l'embrayage électrique étudié en particulier. Suite à des évaluations de performance en physique différente, des pistes d'améliorations ont également été proposées. / In an on-board automotive environment, machines optimal design requires simultaneous consideration of numerous physical phenomena; both in terms of expected performance or in terms of constraints to be respected. The physics that can be affected includes the electromagnetic / electromechanical performance, thermal behavior and vibro-acoustic behavior. Among a large choice of machine, with the manufacturer cost and manufacturing concern taken en into account, the synchronous reluctance machine with segmented has been found to be particularly interesting for application with severe ambient temperature and encumbrance limitation. This study has therefore as objectives to evaluate the capacity of the synchronous reluctance machine in ail physics mentioned and eventually shows the interaction between these physics, thus performance alteration of the machine in operated in the automobile equipment environment. Multi-physics model were developed and confronted to experimental validations using a prototype machine that was developed for an electrical clutch. Using the validated model, different performance figures of synchronous reluctance machines with different rotor topologies were compared. Resulting from the study, valid electromagnetic, electromechanical, thermal and vibro-acoustic models are now available to be used as tools in future machine design. The synchronous reluctance with segmented rotor prototype machine has been shown to be capable to be used in the electrical clutch application studied in particular. Following performance evaluations in different physics, suggestions of improvements have also been proposed.
37

Návrh a optimalizace synchronního reluktančního motoru / Design and optimalisation of synchronous reluctance machine

Bárta, Jan January 2014 (has links)
This theses is related to design of synchronous reluctance motors of the transverse-laminated type. The first part describes synchronous reluctance machine via space-vector theory. Furthermore this part briefly discuss the main design aspects of synchronous reluctance machines. The main part of this thesis is related to practical electromagnetic rotor design for synchronous reluctance machine by means of finite element method. On this base the rotor has been fabricated and placed inside of induction motor instead of his original rotor. On this prototype was made several measurements which were compared with results from finite element method analysis. The last part of this theses is related to short study of synchronous reluctance machine dynamical behaviour under scalar and vector control.
38

Commande intermittente de la machine à réluctance variable à double saillance / Intermittent control of the switched reluctance machine

Nguyen, Duy-Minh 08 July 2019 (has links)
La commande intermittente a pour but principal d'augmenter le rendement de l'ensemble machine-convertisseur par une réduction des pertes. Dans le but de maintenir le couple moyen de la machine requis par la charge, cette commande augmente le couple de référence et éteint quelques phases pendant chaque période électrique ou chaque période mécanique. Par ce fait, elle réduit les pertes du convertisseur et les pertes ferromagnétiques de la machine. Elle dispose également d'une liberté de sélection des phases activées qui influence des fréquences générées du courant, de la force radiale et du couple. Par conséquent, cette stratégie de la commande intermittente, qui est appelée le glissement, peut éviter l'excitation de fréquences naturelles du stator, ou bien celles de la chaine cinématique. Elle a pour but de réduire les effets négatifs de la commande intermittente vis-à-vis de comportements vibratoire du stator et pulsatoire de la chaine cinématique qui sont respectivement à l'origine du bruit acoustique et des à-coups mécaniques. En fin, la commande intermittente est validée sur des cycles de conduite et peut économiser jusqu’à 5,17 % de l’énergie électrique consommée. / The intermittent control aims to increase the efficiency of the machine-converter system by reducing the losses. In the purpose to maintain the average torque of the machine required by the load, this control increases the reference torque and turns off some phases during each electrical period or each mechanical period. By this fact, it reduces the converter losses and the ferromagnetic losses of the machine. It also has a freedom in the selection of the activated phases which influences the generated frequencies of the current, the radial force and the torque. Therefore, this strategy of the intermittent control, which is called sliding strategy, can avoid the excitation of the natural frequencies of the stator, or those of the drivetrain. It aims to reduce the negative effects of the intermittent control vis-à-vis the vibration of the stator and the pulsation of the drivetrain which are respectively at the origins of acoustic noise and mechanical jerks. Finally, the intermittent control is validated on driving cycles and can save up to 5.17 % of the consumed electrical energy.
39

Stratégies de contrôle et analyse des défauts d'une machine à réluctance variable pour une chaîne de traction électrique / Control strategies and faults analysis of the Switched Reluctance Machine (SRM) for an electric vehicle application

Saadi, Yakoub 08 July 2019 (has links)
De nos jours, les véhicules électriques et hybrides ont suscité un très grand intérêt en raison de préoccupations environnementales et énergétiques. Dans ces véhicules, les machines électriques utilisées sont des machines conventionnelles asynchrones et synchrones à aimants permanents. La machine à réluctance variable est une technologie candidate potentielle pour les chaînes de traction électriques et hybrides. Cette machine conçue sans aimants et redondante peut réunir la robustesse et le faible coût de la machine asynchrone aux bonnes performances de la machine synchrone à aimants permanents. Dans ce contexte, le premier objectif de cette thèse est de proposer des stratégies de commandes robustes de la machine à réluctance variable par la prise en compte des contraintes des chaînes de traction électriques en vue de réaliser une étude comparative des performances. Dans cette étude, les commandes proposées sont les commandes classiques de type PI, les commandes par mode glissant et les commandes par mode glissant d'ordre supérieur. Le deuxième objectif consiste à développer des observateurs d'état pour la commande sans capteur de position mécanique de la machine à réluctance variable. Des observateurs robustes basés sur la théorie du filtre de Kalman étendu et les modes glissants sont synthétisés pour atteindre cet objectif. Enfin, le troisième objectif est de faire une analyse des défauts électriques de type circuit ouvert de l'étage électronique de puissance par l'approche signal afin de développer une méthodologie de détection et de localisation automatique de ces défauts. / Nowadays, electric and hybrid vehicles are gaining increased attention due to environmental and energy concerns. In these vehicles, the electrical machines used are the conventional machines, namely induction and permanent magnet synchronous machines. The switched reluctance machine is a potential candidate technology for electric and hybrid drivetrains. This machine designed without magnets and redundant windings, can combine the robustness and low cost of induction machines to the good performance of permanent magnet synchronous machines. In this context, the first objective of this thesis is to propose robust control strategies of the switched reluctance machine, taking into account the constraints of electric vehicles in order to make a comparative performance study. In this study, PI control, sliding mode control and higher order sliding mode control are proposed. The second objective is to develop state observers for sensorless control. Robust observers based on extended Kalman filter theory and sliding modes are synthesized to achieve this goal. Finally, the third objective is to make an analysis of electrical open-circuit faults of the electronic power stage using the signal approach in order to develop a methodology of automatic fault isolation.
40

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.

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