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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.
51

Sintonia dos controladores para aerogeradores de velocidade variável com geradores de indução de dupla alimentação utilizando um algoritmo meta-heurístico de inteligência coletiva / Tuning of controllers for variable speed wind turbines with doubly fed inductions generator using a algoritmo metaheurístico de inteligência coletiva

Aguilar, Milton Ernesto Barrios 04 August 2016 (has links)
Made available in DSpace on 2017-07-10T16:41:35Z (GMT). No. of bitstreams: 1 Dissert Milton Ernesto Barrios Aguilar 3.pdf: 9539969 bytes, checksum: 3ccd249e45fb24533b33236925ee74dc (MD5) Previous issue date: 2016-08-04 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The increase in wind power integration into power systems is currently a general trend in many countries and the Variable-Speed Wind Turbine (VSWT) Equipped with a Doubly Fed Induction Generator System with back-to-back power converters are most often used for this purpose. There is the need for its control system to operate properly to ensure stability and to achieve the desired performance when they are subjected to different transient disturbances, which is a difficult taste due to nonlinearities and strong coupling between electrical and mechanical variables in this type of wind turbine. In this context, this work aims to tune the gains of the PI controllers that make up the control system using a collective intelligence meta-heuristic algorithm for two normal perturbations in the operation of a wind farm: a wind variation and electrical fault. For that, it was modeled the wind turbine taking advantage of detailed modeling, considering the stator voltage oriented control structure, with active and reactive power control loops and their respective current controls, all equipped with PI controllers. Therefore, a set of objective functions was generated penalizing the most important variables directly from the dynamic simulation. Next, a multi-objective PSO algorithm has been enhanced, to be used as a tuning tool. Then the algorithm was applied to the VSWT for Single-machine infinite bus system for wind speed variation and electrical fault. Finally, the robustness of the tunings was tested on the in Single-machine infinite bus system and a 32 nodes feeder. The PSO showed good ability to exploitation and intensification of the search space reaching the preset tuning requirements in all cases. Stability and satisfactory performance results were obtained for transient disturbances thanks to key variables penalty in the objective functions. The tuning resulted robust enough for variations of feeder parameters and operating conditions besides the proper stiffness coefficient of the turbine generator mechanical coupling, whenever the wind turbine was subjected to disturbances considered in the tuning. It is also noted that exploring the objective functions and the algorithm itself can attain a large improvement in the performance of the tuned wind turbine control system for wind variations and electrical faults / O aumento da integração da geração eólica em sistemas elétricos de potência é atualmente uma tendência generalizada em muitos países e os Aerogeradores de Velocidade Variáveis (AVV) com Geradores de Indução de Dupla Alimentação (DFIG) com conversores de potência de tipo back-to-back são os mais empregados para este fim. Existe a necessidade de que seu sistema de controle atue corretamente para garantir a estabilidade e obter o desempenho desejado quando estes são submetidos a diferentes perturbações transitórias, o que resulta difícil devido às não-linearidades e à forte relação entre as grandezas elétricas e mecânicas deste tipo de aerogerador. Neste contexto, esta dissertação tem como objetivo a sintonia dos ganhos dos controladores PI que compõem o sistema de controle, utilizando um algoritmo meta-heurístico de inteligência coletiva, para duas perturbações normais na operação de uma usina eólica: variação de vento e falta elétrica. Para isso, foi modelado o DFIG aproveitando modelos detalhados, considerando a estrutura de controle orientada pela tensão do estator, com malhas de controle de potência ativa e reativa e seus respetivos controles de correntes, todas equipadas com controladores tipo PI. Logo foi gerado um conjunto de funções objetivos, penalizando diretamente das simulação dinâmica as variáveis de maior importância. A seguir, foi aprimorado um algoritmo PSO multi-objetivo, o qual é utilizado como ferramenta de sintonia. Em seguida, o algoritmo foi aplicado ao DFIG na configuração máquina barra-infinita para variação de vento e falta elétrica. Finalmente foi testada a robustez das sintonias obtidas no sistema de máquina barra-infinita e em um alimentador de 32 nós. O PSO apresentou uma boa capacidade de exploração e intensificação do espaço de busca alcançando os requisitos de sintonia preestabelecidos em todos os casos. Os resultados de estabilidade e desempenhos foram satisfatórios para as perturbações transitórias utilizadas graças à penalização de variáveis chaves nas funções objetivos. A sintonia resultou suficientemente robusta para variações de parâmetros do alimentador e de condições operativas, além do próprio coeficiente de rigidez do acoplamento mecânico turbina-gerador, sempre que a usina esteja submetida a perturbações consideradas na sintonia. Observa-se também que explorando as funções objetivo e o próprio algoritmo pode-se atingir uma ampla melhoria no desempenho do sistema de controle do DFIG sintonizado para as variações de vento e faltas elétricas. Palavras-chave: Geração Eólica, Aerogeradores
52

Wind energy and power system interconnection, control, and operation for high penetration of wind power

Liang, Jiaqi 08 March 2012 (has links)
High penetration of wind energy requires innovations in different areas of power engineering. Methods for improving wind energy and power system interconnection, control, and operation are proposed in this dissertation. A feed-forward transient compensation control scheme is proposed to enhance the low-voltage ride-through capability of wind turbines equipped with doubly fed induction generators. Stator-voltage transient compensation terms are introduced to suppress rotor-current overshoots and torque ripples during grid faults. A dynamic stochastic optimal power flow control scheme is proposed to optimally reroute real-time active and reactive power flow in the presence of high variability and uncertainty. The performance of the proposed power flow control scheme is demonstrated in test power systems with large wind plants. A combined energy-and-reserve wind market scheme is proposed to reduce wind production uncertainty. Variable wind reserve products are created to absorb part of the wind production variation. These fast wind reserve products can then be used to regulate system frequency and improve system security.
53

Ανάλυση και σχεδίαση απευθείας ελέγχου πραγματικής και άεργου ισχύος σε αιολικό σύστημα με επαγωγική γεννήτρια διπλής τροφοδοσίας

Κεραμίδας, Αθανάσιος 03 April 2015 (has links)
Η παρούσα διπλωματική εργασία πραγματεύεται την ανάλυση και σχεδίαση απευθείας ελέγχου πραγματικής και άεργου ισχύος σε αιολικό σύστημα με επαγωγική γεννήτρια διπλής τροφοδοσίας (Doubly-Fed Induction Generator, DFIG). Κύριος σκοπός της εργασίας είναι η εξαγωγή ενός κατάλληλου δυναμικού μοντέλου του συστήματος, το οποίο περιέχει ως καταστάσεις τις ισχείς. Επιπλέον, μέσω του διανυσματικού ελέγχου με προσανατολισμό στην τάση του δικτύου (Voltage-Oriented Control, VOC) επιτυγχάνεται ο απευθείας έλεγχος των ισχύων χρησιμοποιώντας αναλογικό-ολοκληρωτικούς (Proportional-Integral, PI) ελεγκτές, επιβάλλοντας με αυτόν τον τρόπο την επιθυμητή μεταβατική συμπεριφορά. Τελικά, η ανάλυση και η συμπεριφορά του αιολικού συστήματος επιβεβαιώνεται με τα αποτελέσματα της εξομοίωσης σε περιβάλλον MATLAB/Simulink. Ειδικότερα, στο κεφάλαιο 1 παρουσιάζονται το ενεργειακό πρόβλημα και τα διάφορα είδη ανανεώσιμων πηγών ενέργειας. Στο κεφάλαιο 2 αναφέρονται τα συστήματα αιολικής ενέργειας. Πιο συγκεκριμένα, περιγράφονται οι κυριότεροι τύποι ανεμογεννητριών και η δομή της, οι γεννήτριες και οι συσκευές ηλεκτρονικών ισχύος που χρησιμοποιούνται σε ένα αιολικό σύστημα, καθώς και ο μηχανικός έλεγχος ισχύος που μπορεί να εφαρμοστεί. Στη συνέχεια, στο κεφάλαιο 3 πραγματοποιείται η ανάλυση του αιολικού συστήματος με την DFIG όπου εξάγεται με την βοήθεια του μετασχηματισμού Park, το ζητούμενο μαθηματικό μοντέλο. Έπειτα, στο κεφάλαιο 4 αναφέρονται οι μέθοδοι ελέγχου που χρησιμοποιούνται στις ανεμογεννήτριες, εφαρμόζεται ο VOC στο αιολικό σύστημα που μελετάται και σχεδιάζονται οι απαιτούμενοι ελεγκτές PI ώστε να ελεγχθεί η ισχύς μέσω των δύο μετατροπέων ισχύος. Τέλος, στο κεφάλαιο 5 παρουσιάζεται η εξομοίωση του συστήματος και τα αποτελέσματα που προέκυψαν. / This diploma thesis deals with the analysis and design of a direct active and reactive power control system for a Doubly-Fed Induction Generator (DFIG) wind power system. The main purpose of this thesis is to extract a suitable dynamic model of the system that contains as states the active and reactive power. In addition, the direct control of the active and reactive power is achieved through voltage-oriented control (VOC) and the use of PI controllers, imposing the desirable transient behavior. Finally, the analysis and the performance of the wind system are verified through simulation results in MATLAB/Simulink. Specifically, in chapter 1 the energy problem and the different types of renewable energy sources are presented. The second chapter deals with the wind energy systems. In particular, the main types and the structure of wind turbines, the generators, the power electronic devices and the mechanic power control used in a wind power system are presented. Then, in chapter 3 the DFIG wind system is analysed and the required mathematical model is extracted using Park’s transformation. Next, in the fourth chapter the control methods for a wind turbine are presented and, using the VOC in the wind power system studied, the required PI controllers for the two power converters are designed. Finally, in chapter 5 the simulation results are presented and conclusions are drawn.
54

Advances in power system small signal stability analysis considering load modeling and emerging generation resource

Yateendra Mishra Unknown Date (has links)
With the increasing complexity of the power system, electromechanical oscillations are becoming one of the major problem. Several blackouts have been reported in the past due to insufficient damping of the oscillatory modes. The starting point to avoid catastrophic behaviors would be to simulate actual power system and study the response of the system under various outages leading to blackouts. Recently, it has been identified that appropriate modeling of the load is necessary to match the actual system behavior with the computer simulated response. This research throws some insight into the detailed load modeling and its impact on the system small signal stability. In particular, Composite load model is proposed and its effect on the system small signal stability is investigated. Modeling all the loads in a large power system would be a cumbersome job and hence the method for identifying the most sensitive load location is also proposed in the thesis. The effect of load modeling on the eigenvalue movement is also investigated. The low damped electromechanical modes are always undesirable in the large inter-connected power systems as they might get excited under some event leading to growing oscillations. Proper damping of these modes is essential for effective and reliable system operation. Power system stabilizers have been proved to be an effective way of damping these electromechanical modes. The optimal number and location of PSS to effectively damp the modes via improved Differential algorithm is proposed. Moreover, the effect of TCSC, series compensated FACTs device, on enhancing the system damping is investigated. A fixed order model matching technique is presented to design a damping controller for the TCSC. With the increasing global pressure for reducing carbon emissions, there is a great amount of interest in the renewable sources of energy, particularly Wind Energy Conversion Systems. Of all the present methods of wind generation systems, Doubly Fed Induction Generation (DFIG) based wind farms are gaining popularity. The comparison of various methods of wind generation techniques is presented. In particular, the impact of DFIG based wind farms on the system small signal stability is investigated in this work. Co-ordinated tuning of the controllers is performed using Bacterial Foraging Technique, which is another member of Evolutionary algorithms. Damping controller for the DFIG system is proposed to enhance the damping of the electromechanical modes. Results have proved the effectiveness of the control methodology. The contributions made in this thesis could be utilized to promote the further development of the damping controllers for large power systems.
55

Advances in power system small signal stability analysis considering load modeling and emerging generation resource

Yateendra Mishra Unknown Date (has links)
With the increasing complexity of the power system, electromechanical oscillations are becoming one of the major problem. Several blackouts have been reported in the past due to insufficient damping of the oscillatory modes. The starting point to avoid catastrophic behaviors would be to simulate actual power system and study the response of the system under various outages leading to blackouts. Recently, it has been identified that appropriate modeling of the load is necessary to match the actual system behavior with the computer simulated response. This research throws some insight into the detailed load modeling and its impact on the system small signal stability. In particular, Composite load model is proposed and its effect on the system small signal stability is investigated. Modeling all the loads in a large power system would be a cumbersome job and hence the method for identifying the most sensitive load location is also proposed in the thesis. The effect of load modeling on the eigenvalue movement is also investigated. The low damped electromechanical modes are always undesirable in the large inter-connected power systems as they might get excited under some event leading to growing oscillations. Proper damping of these modes is essential for effective and reliable system operation. Power system stabilizers have been proved to be an effective way of damping these electromechanical modes. The optimal number and location of PSS to effectively damp the modes via improved Differential algorithm is proposed. Moreover, the effect of TCSC, series compensated FACTs device, on enhancing the system damping is investigated. A fixed order model matching technique is presented to design a damping controller for the TCSC. With the increasing global pressure for reducing carbon emissions, there is a great amount of interest in the renewable sources of energy, particularly Wind Energy Conversion Systems. Of all the present methods of wind generation systems, Doubly Fed Induction Generation (DFIG) based wind farms are gaining popularity. The comparison of various methods of wind generation techniques is presented. In particular, the impact of DFIG based wind farms on the system small signal stability is investigated in this work. Co-ordinated tuning of the controllers is performed using Bacterial Foraging Technique, which is another member of Evolutionary algorithms. Damping controller for the DFIG system is proposed to enhance the damping of the electromechanical modes. Results have proved the effectiveness of the control methodology. The contributions made in this thesis could be utilized to promote the further development of the damping controllers for large power systems.
56

Reconfiguration du dispositif de commande d’une éolienne en cas de creux de tension / Control reconfiguration of a doubly fed induction machine based wind generator to increase the low voltage ride through capability

Peng, Ling 17 June 2010 (has links)
Avec le développement de l’éolien, les prescriptions techniques de raccordement de cette technologie obligeront le maintient de sa connexion lors d’incidents sur la tension du réseau électrique. L’enjeu pour le gestionnaire du réseau est de pouvoir utiliser tous les générateurs pour garantir la stabilité du système électrique.A partir d’un modèle dynamique d’une éolienne à base de Machine Asynchrone à Double Alimentation (MADA), une commande vectorielle améliorée a été proposée en prenant en compte la dynamique du flux statorique engendrée par la chute de tension. Les performances supérieures en terme de maintient de la production ont été établies par comparaison avec la méthode de commande classique. Son domaine d’utilisation a été également déterminé.Pendant les creux de tension importants, une protection matérielle (crowbar) est implémentée avec un contrôle de la démagnétisation de la MADA. En outre, de la puissance réactive peut être produite à la fois par la MADA et par le convertisseur connecté au réseau électrique au cours de la défaillance du réseau.Un contrôle vectoriel à hystérésis des courants pour les deux convertisseurs électroniques multiniveaux est proposé et évalué pour améliorer la réponse dynamique de ces convertisseurs et pour réduire les effets des variations des paramètres sur les performances de la commande. Selon la durée du défaut, des objectifs différents de contrôle doivent être réalisés en priorité pour empêcher des surintensités rotoriques et pour fournir de la puissance réactive. Une reconfiguration complète du dispositif de commande de cette éolienne est détaillée pour renforcer le maintient de la production éolienne lors de défaillances / With the massive development of wind energy, the technical requirements for connecting this technology will require the improvement of the fault ride-through capability of grid-connected wind turbines. The task for the grid system operator is to use all generators to ensure the stability of the electrical system.From a dynamic model of a Doubly Fed Induction Generator (DFIG) based wind generator, an improved vector control has been proposed by taking into account the dynamics of the magnetic flux, which are generated by the voltage dip. The higher performances have been established by comparison with the conventional control method. The operation domain was also determined.During serious voltage dips, a hysteresis control scheme of the active Crowbar is proposed to protect the system within a demagnetization method of the DFIG. Moreover, additional reactive power can be produced both by the MADA and the grid-side converter in order to support the electric network during the grid fault.A space vector hysteresis current control strategy of both three-level converters is proposed to improve the dynamic response of the system and to reduce the parameter variation effects on the control performanceDepending on the grid fault duration, different control objectives have to be achieved with priority to restrain the rotor over-current or to supply reactive power. Then the reconfiguration scheme of the control strategies of high power DFIG wind turbine system is proposed to enhance the fault ride-through capability of the DFIG system. With this specific methodology, the DFIG can stay connected and can supply maximal reactive current during voltage dips to help voltage recovery
57

Modeling and Analysis of Grid Connected Variable Speed Wind Generators

Seshadri Sravan Kumar, V January 2015 (has links) (PDF)
The growing demand for power and increased environmental concerns gave an impetus to the growth of clean and renewable energy sources like wind, solar etc. There is a remarkable increase in the penetration of wind energy systems in the last decade and this trend is bound to increase at a much faster pace in future. This ever increasing penetration of wind power generating systems pose multi-fold challenges related to operational and stability aspects of the grid. Present day wind energy systems mostly comprise of variable speed wind generators. A large fraction of present day variable speed wind turbine generators use doubly fed induction machine (DFIM). This thesis deals with modeling and grid coordination aspects of variable speed wind gener- ators. In particular, the short coming of the existing steady state equivalent circuit of a DFIM is identified and subsequently, an accurate equivalent circuit of a DFIM is proposed. Relevant mathematical basis for the proposed model is presented. The proposed steady state equivalent circuit of a doubly fed induction machine is further validated using dynamic simulations of a standalone machine. Based on the proposed equivalent circuit, two approaches for computing the initial values of state variables of a DFIM is proposed. The first approach is a linear formulation where the losses due to resistance of the stator and rotor windings are neglected. The second approach is a non-linear formulation which takes the losses into consideration. Further, analysis is carried out on grid connected doubly fed induction generators (DFIG). A framework to incorporate DFIG based variable speed wind farms in the steady state power flow analysis is proposed. The proposed framework takes into consideration important aspects such as voltage dependent reactive power limits and mode of reactive power control of associated converters. Some of the challenges in a grid connected DFIG especially during su- persynchronous mode of operation are identified. The advantages of a non-Maximum Power Point Tracking (MPPT) mode of operation under certain operating conditions is highlighted. Finally, aspects pertaining to coordination of grid connected variable speed wind generators are studied. A trust region framework to determine the reference values to the control loops of converters in a variable speed wind generator is proposed. The proposed framework identifies the reference values considering other reactive power controllers in the grid. Moreover, the proposed framework ensures that the steady state voltage stability margin is maximized. On the computational front, trust region algorithms ensure global convergence. The mathematical models and initialization algorithms proposed in this thesis are tested on standalone systems under various control scenarios. The algorithms proposed to incorporate a grid connected DFIG in steady state analysis tools have been tested on a sample 6-bus system and a practical 418-bus equivalent system of Indian southern grid.
58

Proposta de projeto de ganhos de controladores PI empregados no controle de geradores de indução com rotor bobinado aplicados a sistemas eólicos

Murari, André Luiz de Lacerda Ferreira January 2015 (has links)
Orientador: Prof. Dr. Alfeu Joãozinho Sguarezi Filho / Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Engenharia Elétrica, 2015. / Inicialmente, este trabalho apresenta aspectos de viabilidade e técnicos para a construção de sistemas de geração eólicos. Nele é disposto uma breve literatura de alguns dos conversores elétricos utilizados para diferentes tipos de geradores. Por fim, este trabalho propõe um método de ajuste de ganhos dos controladores proporcionais-integrais através do emprego do método por compensação de polos da função de transferência do sistema em malha fechada, para o conversor do lado do rotor, com objetivo de garantir controle estável do fluxo das potências ativa e reativa de estator do GIRB. Também, serão apresentadas as malhas de controle do conversor conectado à rede elétrica. Resultados obtidos através de simulação computacional deste sistema de controle são apresentados para validar a proposta. / This work includes feasibility and technical aspects for the construction of wind generation systems. In it, there is disposed a brief literature some electrical converters used for different types of generators. It also presents a design method for the gains of the proportional-integral controllers used in power vector control of DFIG connected to the grid in wind power generation systems where GIRB is connected directly to the power grid and its rotor through a converter called "back to back". The rotor controllers will be adjusted with the use of the method for compensating poles of the system's transfer function in closed loop. Also, the converter control loops connected to the grid will be displayed. Results from computer simulation of this control system are presented to validate the proposal.
59

Contribuição ao estudo do gerador de indução duplamente alimentado: operação durante distúrbios na rede elétrica / Contribution to study of doubly-fed induction generators: operation under network disturbances

Costa, Jean Patric da 30 August 2010 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / The Doubly Fed Induction Generator (DFIG) is one of the most frequently deployed large grid connected Wind Turbines (WT) concept. The implementation of classical vector control techniques, have been proven to work well for considering the initial grid code requirements. However, recently many grid operators are requiring WT to remain connected during grid faults, resulting in low voltage fault ride through capability (LVRT). In addition, it is required for WTs to contribute with reactive support during the fault. As a result, the improvements of the transient behavior of the DFIG, the power converter protection and the controller design have become a challenge for WT manufactures. This work presents a high performance stationary frame non-linear controller for doubly fed induction generator, which improves the steady state and transient behavior of the grid connected wind turbines especially under unbalance voltage dips resulting from network unbalance faults. A controller design procedure that guarantees the DFIG stability under uncertainties and disturbances at grid side is presented in details. Furthermore, it is demonstrated in the thesis that with the proposed controller different goals such as control of grid side active and reactive power, minimization of torque pulsation under unbalance operation and improvement of the low voltage ride through capability can be easily achieved. Simulations and experimental results are given to illustrate the good performance of a grid connected DFIG with the proposed controller. / Turbinas eólicas modernas que utilizam o Gerador de Indução Duplamente Alimentado (GIDA) são amplamente empregadas para geração de energia elétrica. Essa grande parcela de aero-geradores baseados na tecnologia GIDA e técnicas de controle vetorial clássicas já comprovaram ao longo dos últimos anos que este conceito apresenta méritos e foi capaz de satisfazer requisitos de conexão de turbinas eólicas com a rede elétrica inicialmente elaborados. No entanto, atualmente, os operadores do sistema estão revisando os códigos de rede em muitos países, introduzindo novos requisitos e estreitando os limites definidos inicialmente. Basicamente, os geradores eólicos estão assumindo maiores responsabilidades no sistema de potência. A capacidade de sobrevivência e suporte de reativos durante afundamentos de tensão, introduzidos nos novos códigos de rede, tornaram-se os maiores desafios para os fabricantes de aero-geradores com tecnologia GIDA. Essa tese de doutorado tem como principal objetivo desenvolver estratégias de controle para melhorar o desempenho dinâmico do Gerador de Indução Duplamente Alimentado conectado a rede elétrica frente aos requisitos de sobrevivência aos afundamentos de tensão no Ponto de Conexão (PC). Para isso, essa tese propõe um controlador não linear de alto desempenho baseado em modos deslizantes para o controle do GIDA em eixos estacionários. O controlador proposto melhora o comportamento transitório do GIDA principalmente durante distúrbios na tensão no PC. O projeto do controlador é desenvolvido de forma a garantir a estabilidade do GIDA conectado à rede elétrica mesmo considerando incertezas associadas ao modelo nominal. Outras características do controlador proposto, além da robustez, são a sua simplicidade de implementação e a sua excelente resposta transitória. Ainda, dois modos de operação são propostos para geração de referência do GIDA, MODO 1 para operação em condições normais da tensão da rede elétrica, MODO 2 com uma metodologia para o cálculo das referências de corrente de forma a dar suporte de reativos durante faltas próximas ao PC. O comportamento dinâmico do sistema e o desempenho da estratégia de controle são verificadas através de simulações e também experimentalmente.
60

Fault-tolerance and noise and vibration aspects of electrical drives: Application to wind turbines and electrical vehicle traction

Mollet, Yves 06 November 2017 (has links)
The awareness of the human responsibility in global warming has led to various private and public initiatives to reduce the emission of greenhouse gases, up to international level. In this context the development of renewable technologies in two sectors having an important ecological footprint, i.e. production of electricity and transportation, is targeted.In the firstly mentioned sector, the progression of wind energy is at present the most rapid among all renewable energies. But wind turbines still suffer from a global lack of reliability and accessibility compared to classical power plants, leading to potentially important production losses and repair costs. The first part of the present work focuses on the improvement of the electrical chain reliability by the combination of an estimator and a fault-detection algorithm to achieve sensor-fault tolerance, taking benefit from the already available measurement redundancies on doubly-fed-induction-machine (DFIG) drives.Estimators and sensor-fault detection and isolation (FDI) in DFIGs have been the object of many research papers. However, most of them only consider one unique type of measurement and only a few works consider magnetic saturation. A new combination of a closed-loop observer with a cumulative-sum-based FDI technique, considering magnetic saturation and using limited computational resources is proposed here to estimate electromagnetic torque, rotor currents and position for sensor-fault detection and tolerance. This algorithm is then validated in steady state and in case of moderate transients, unbalanced conditions and misestimation of DFIG parameters. The estimator can also start on the fly during the start-up process of the generator.In the transportation sector, new hybrid and full-electric vehicles start to be visible on the roads, but still need important technological improvements in terms of autonomy, performances, but also produced noise and vibrations. The objectives of the second part of this doctoral thesis are related to this last challenge and consist of the experimental investigation of noise, vibration and harshness (NVH) aspects of an 8/6 switched-reluctance machine (SRM) designed for an electrical vehicle (EV).The NVH issues of SRMs, limiting their usage in automotive and other domains, have been the subject of various papers. However, most of them focus on modal analysis or detailed phenomena, while a global evaluation of NVH aspects of SRMs in normal working conditions is rarely made, as well as the use of reproducible sound metrics. A global and relatively fast experimental method to assess the evolution of noise and vibration is proposed. Tests are performed in transient regime, using continuously varying working conditions when possible, for the excitation of a large band of frequencies. The resulting current, radial vibration and acoustic noise are presented as spectrograms for an easy distinction of affected and unaffected frequencies and compared with the associated loudness and sharpness.Furthermore, the implementation of a new faster-sampled current-hysteresis controller has allowed to improve the quality of the control and of the acoustic noise by reducing the current-ripple amplitude and the excitation of resonances. The various tests show that the switching frequency has to be high enough to avoid exciting the ovalization mode of the SRM, but not too high to avoid producing a too sharp noise. The ripple amplitude also has to be considered to limit the loudness. Therefore, soft chopping, or a reduced DC-bus voltage at low speeds, has to be preferred with a relative small hysteresis bandwidth. Finally, the case of an open-phase fault has been investigated showing amplified even current orders in the vibration and acoustic-noise plots. / La prise de conscience de la responsabilité humaine dans le réchauffement climatique est à la source de nombreuses initiatives publiques et privées parfois internationales pour réduire les émissions de gaz à effet de serre. Dans ce contexte, le développement de technologies durables dans deux secteurs à forte empreinte écologique est visé: la production d'énergie électrique et les transports. Dans le premier secteur, la progression de l'éolien est à présent la plus rapide parmi toutes les énergies renouvelables. Cependant, les éoliennes souffrent d'un manque global de fiabilité et d'accessibilité par rapport aux centrales électriques classiques, ce qui conduit potentiellement à des pertes de production et des coûts de réparation importants. La première partie de ce travail se focalise sur l'amélioration de la chaîne électrique en la rendant tolérante aux défauts de capteurs au moyen de la combinaison d'un estimateur et d'un algorithme de détection de défauts, tirant avantage de la redondance de mesures déjà présente sur les entraînements à machines asynchrones à double alimentation (MADA). Les estimateurs et la détection et l'isolation de défauts de capteurs sur les MADA a fait l'objet de nombreuses publications scientifiques. Cependant, la plupart d'entre elles considèrent un seul type de mesure et peu de travaux prennent en compte la saturation magnétique. Une nouvelle combinaison d'un observateur et d'un algorithme de détection de défauts de type ‘CUSUM', considérant la saturation magnétique et nécessitant une puissance de calcul limitée, est proposée dans cette thèse pour l'estimation du couple électromagnétique, des courants et de la position rotoriques en vue d'obtenir la tolérance aux défauts de capteurs. Cet algorithme est validé en régime permanent et cas de transitoires modérés, de tensions du réseau déséquilibrées et d'erreurs d'estimation des paramètres de laMADA. L'estimateur est aussi capable de démarrer seul lors du démarrage de la génératrice. Dans le secteur des transports, des véhicules hybrides et électriques commencent à être visibles sur les routes, malgré que des progrès technologiques importants en termes d'autonomie, de performances, mais aussi de bruits et vibrations soient encore nécessaires pour une utilisation plus intensive. L'objectif de la deuxième partie de cette thèse se rapporte à ce dernier défi et consiste à analyser les aspects acoustiques et vibratoires d'une machine à réluctance variable 8/6 conçue pour propulser un véhicule électrique. Ces problèmes acoustiques et vibratoires, qui limitent notamment l'usage de telles machines dans des applications de propulsion, ont été l'objet de divers articles scientifiques. Cependant, la plupart d'entre eux sont focalisés sur des analyses modales ou de phénomènes particuliers, alors qu'une évaluation globale des problèmes de bruit et de vibration des machines à réluctance variable en conditions normales de fonctionnement est rarement proposée, de même que l'utilisation de critères de qualité sonore. Une méthode expérimentale globale et relativement rapide pour évaluer l'évolution du bruit et des vibrations est proposée dans ce travail. Les essais sont réalisés en régime transitoire pour exciter une large bande de fréquences et en faisant varier continuellement, quand cela est possible, les conditions de fonctionnement. Les courants, vibrations radiales et bruits acoustiques résultants sont présentés sous formes de cartographies couleur pour une distinction aisée des fréquences affectées et non-affectées et comparés aux niveaux calculés de bruyance et d'acuité correspondants. Par ailleurs, la mise en place d'un nouveau régulateur à hystérèse en courant à plus grande fréquence d'échantillonnage a permis d'améliorer la qualité de la commande et du bruit acoustique associé en réduisant l'amplitude des oscillations de courant et l'excitation des fréquences de résonance. Les essais montrent que la fréquence de commutation doit être suffisamment élevée pour éviter l'excitation du mode d'ovalisation de la machine, mais pas trop pour éviter une trop grande acuité du son produit. L'amplitude des oscillations doit aussi être considérée pour limiter la bruyance. En conséquence, une commande en ‘soft chopping', ou une tension réduite du bus continu à basse vitesse, doit être combinée à une bande d'hystérèse relativement faible. Enfin, le cas d'un défaut de phase ouverte a été étudié et a montré une amplification des ordres pairs du courant dans les spectres vibratoires et acoustiques. / De bewustwording van de menselijke verantwoordelijkheid in de opwarming van de aarde heeft tot verschillende private en publieke initiatieven geleid om de uitstoot van broeikasgassen te verminderen. In deze context is de ontwikkeling van hernieuwbare technologieën hoofdzakelijk gericht op twee sectoren met een belangrijke ecologische impact: elektriciteitsproductie en transport.In de eerste sector ontwikkelt windenergie zich op dit moment sneller dan alle andere hernieuwbare energieën. Maar windturbines lijden nog steeds aan een gebrek aan betrouwbaarheid en toegankelijkheid, en dus aan potentieel hogere productieverliezen en herstelkosten, als ze met klassieke krachtcentrales worden vergeleken. In het eerste deel van deze doctoraatsthesis wordt op de verbetering van de elektrische keten geconcentreerd door de combinatie van een schatter en een foutdetectie- en -isolatiealgoritme (FDI-algoritme) om sensorfouttolerantie te verkrijgen dankzij de reeds aanwezige meetovertolligheid op dubbelgevoede inductiemachine (DFIG) aandrijvingen.Schatters en sensor-FDI-algoritmen zijn het onderwerp van vele wetenschappelijke artikelen geweest. Meestal wordt maar één sensortype beschouwd en met de magnetische verzadiging wordt niet vaak rekening gehouden. Een nieuwe combinatie van een schatter met gesloten terugkoppeling en een FDI-techniek gebaseerd op het ‘cumulative-sum' principe is voorgesteld. Zo kan het elektromagnetische koppel, de rotorstromen en positie worden geschat voor sensor FDI en fouttolerantie met beperkte rekenkosten en zonder de magnetische verzadering te verwaarlozen. Het algoritme wordt in stabiele toestand gevalideerd, maar ook in het geval van gematigde transiënte situaties, onevenwichtige netwerkomstandigheden en een verkeerde schatting van DFIG parameters. Het kan ook vanzelf starten tijdens de startprocedure van de generator.In de vervoersector beginnen hybride en elektrische voertuigen op de wegen te rijden. Maar vooreen intensiever gebruik van zo'n wagens zijn er nog technologische verbeteringen nodig met betrekking tot autonomie, prestaties en ook geluid en trillingen (NVH). Het tweede deel van de thesis betreft die laatste uitdaging en bestaat uit het experimentele onderzoek van geluid en trillingen op een 8/6 variabelereluctantiemachine (SRM) ontwikkeld voor elektrische voertuigen.De NVH-problemen van SRM's beperken hun gebruik in automobiele en andere toepassingen enonderzoek wordt erover voortgezet. Vele wetenschappelijke artikelen focussen toch op modale analyse of gedetailleerde fenomenen terwijl een globale evaluatie van NVH aspecten in SRM's in gewone operatiecondities nauwelijks wordt gemaakt. Hetzelfde geldt voor het gebruik van reproduceerbare geluidsmetrieken. Een globale en vrij vlugge experimentele methode is hier voorgesteld om het NVH gedrag te schatten. Testen worden in transiënte situaties uitgevoerd om een brede frequentieband te exciteren, indien mogelijk met voortdurend variërende condities. De gemeten fasestroom, trilling en geluid worden als kleurmappen geplot om het verschil tussen beïnvloede en niet geaffecteerde frequenties te vergemakkelijken en met de berekende akoestische luidheid en scherpte vergeleken.Bovendien heeft de implementatie van een sneller bemonsterd stroomhysteresisregelaar geleid tot een verbetering van de regulatie- en akoestische kwaliteit door de amplitude van de stroomrimpeling en de excitatie van resonantiefrequenties te verminderen. De testresultaten tonen dat de schakelfrequentie voldoende hoog moet zijn om de excitatie van de ovale vervormingsmode te vermijden, maar niet te hoog om de scherpte van het geluid te beperken. De amplitude van de rimpel beïnvloedt ook de luidheid en daarvoor moet in aanmerking worden genomen. Bijgevolg zou ‘soft chopping'mode, of een lagere spanning op de DC-bus bij lage toerentallen, met een relatief klein hysteresisband beter worden gebruikt. Uiteindelijk wordt het geval van een openfasefout bestudeerd en onthult versterkte gelijke frequentievolgorden in de trilling- en geluidplots. / Doctorat en Sciences de l'ingénieur et technologie / info:eu-repo/semantics/nonPublished

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