A DC power distribution system (PDS) of a transport aircraft was modeled and analyzed using MATLAB/Simulink software. The multi-level modeling concept was used as a modeling approach, which assumes modeling subsystem of the PDS at three different levels of complexity. The subsystem models were implemented in Simulink and combined into the whole PDS model according to certain interconnection rules. Effective modeling of different scenarios of operation was achieved by mixing subsystem models of different levels in one PDS model. Linearized models were obtained from the nonlinear PDS model for stability analysis and control design. The PDS model was used to examine the system stability and the DC bus power quality under bidirectional power flow conditions. Small-signal analysis techniques were employed to study stability issues resulting from subsystem interactions. The DC bus stability diagram was proposed for predicting stability of the PDS with different types of loads without performing an actual stability test based on regular stability analysis tools. Certain PDS configurations and operational scenarios leading to instability were identified. An analysis of energy transfer in the PDS showed that a large energy storage capacitor in the input filter of a flight control actuator is effective for reduction of the DC bus voltage disturbances produced by regenerative action of the actuator. However, energy storage capacitors do not provide energy savings in the PDS and do not increase its overall efficiency. / Master of Science

With the development of solar energy, power conversion systems responsible for energy delivering from photovoltaic (PV) modules to ac or dc grid attract wide attentions and have significantly increased installations worldwide. Modular power conversion system has the highest efficiency of maximum power point tacking (MPPT), which can transfer more solar power to electricity. However, this system suffers the drawbacks of low power conversion efficiency and high cost due to a large number of power electronics converters. High-power density can provide potentials to reduce cost through the reduction of components and potting materials. Nowadays, the power electronics converters with the conventional silicon (Si) based power semiconductor devices are developed maturely and have limited improvements regarding in power conversion efficiency and power density. With the availability of wide bandgap devices, the power electronics converters have extended opportunities to achieve higher efficiency and higher power density due to the desirable features of wide bandgap devices, such as low on-state resistance, small junction capacitance and high switching speed. This dissertation focuses on the application of wide bandgap devices to the dc-dc power conversion for the modular PV applications in an effort to improve the power conversion efficiency and power density. Firstly, the structure of gallium-nitride (GaN) device is studied theoretically and characteristics of GaN device are evaluated under testing with both hard-switching and soft-switching conditions. The device performance during steady-state and transitions are explored under different power level conditions and compared with Si based devices. Secondly, an isolated high-efficiency GaN-based dc-dc converter with capability of wide range regulation is proposed for modular PV applications. The circuit configuration of secondary side is a proposed active-boost-rectifier, which merges a Boost circuit and a voltage-doubler rectifier. With implementation of the proposed double-pulse duty cycle modulation method, the active-boost-rectifier can not only serve for synchronous rectification but also achieve the voltage boost function. The proposed converter can achieve zero-voltage-switching (ZVS) of primary side switches and zero-current-switching (ZCS) of secondary side switches regardless of the input voltages or output power levels. Therefore, the proposed converter not only keeps the benefits of highly-efficient series resonant converter (SRC) but also achieves a higher voltage gain than SRC and a wide range regulation ability without adding additional switches while operating under the fixed-frequency condition. GaN devices are utilized in both primary and secondary sides. A 300-W hardware prototype is built to achieve a peak efficiency of 98.9% and a California Energy Commission (CEC) weighted efficiency of 98.7% under nominal input voltage condition. Finally, the proposed converter is designed and optimized at 1-MHz switching frequency to pursue the feature of high-power density. Considering the ac effects under high frequency, the magnetic components and PCB structure are optimized with finite element method (FEM) simulations. Compared with 140-kHz design, the volume of 1-MHz design can reduce more than 70%, while the CEC efficiency only drops 0.8% at nominal input voltage condition. There are also key findings on circuit design techniques to reduce parasitic effects. The parasitic inductances induced from PCB layout of primary side circuit can cause the unbalanced resonant current between positive and negative half cycles if the power loops of two half cycles have asymmetrical parasitic inductances. Moreover, these parasitic inductances reflecting to secondary side should be considered into the design of resonant inductance. The parasitic capacitances of secondary side could affect ZVS transitions and increase the required magnetizing current. Because of large parasitic capacitances, the dead-time period occupies a large percentage of entire switching period in MHz operations, which should be taken into consideration when designing the resonant frequency of resonant network. / Doctor of Philosophy / Solar energy is one of the most promising renewable energies to replace the conventional fossils. Power electronics converters are necessary to transfer power from solar panels to dc or ac grid. Since the output of solar panel is low voltage with a wide range and the grid side is high voltage, this power converter should meet the basic requirements of high step up and wide range regulation. Additionally, high power conversion efficiency is an important design purpose in order to save energy. The existing solutions have limitations of narrow regulating range, low efficiency or complicated circuit structure. Recently, the third-generation power semiconductors attract more and more attentions who can help to reduce the power loss. They are named as wide band gap devices. This dissertation proposed a wide band gap devices based power converter with ability of wide regulating range, high power conversion efficiency and simple circuit structure. Moreover, this proposed converter is further designed for high power density, which reduces more than 70% of volume. In this way, small power converter can merge into the junction box of solar panel, which can reduce cost and be convenient for installations.

L’électricité prend une place de plus en plus importante dans les systèmes énergétiques embarqués. L’électricité est une forme d’énergie très malléable, facile à transporter et réglable ou transformable avec un très faible taux de pertes. L’énergie électrique, associée à des convertisseurs statiques, est plus facile à maîtriser que, par exemple, l’énergie hydraulique et/ou pneumatique, permettant un réglage plus fin et une réduction des coûts de maintenance. L’évolution de la puissance dans les modèles avioniques est marquante. Avec le nombre croissant de charges électroniques, un avion plus électrique avec un réseau à courant alternatif inclurait un grand nombre de redresseurs AC/DC qui devront respecter les normes de qualité secteur. Une solution pour la réduction de la masse serait de préférer un réseau HVDC (High Voltage DC Bus). Sur les futurs modèles avioniques plus électriques, les concepteurs envisageront des conversions HVDC/DC à partir de l’unité appelée BBCU (Buck Boost Converter Unit). Dans ce cas d’étude, un réseau de distribution en tension continue (±270Vdc) est connecté à un réseau de sécurité basse tension (28Vdc) avec un échange bidirectionnel de puissance pouvant atteindre 10kW. Le convertisseur statique assurant cette liaison représente de nouveaux défis pour l’électronique de puissance en termes de fiabilité, sûreté, détection de panne, rendement et réduction de masse et de coût. Le dimensionnement du convertisseur doit prendre en compte une conception optimale, en aéronautique ce critère est la masse. Dans le processus de dimensionnement et d’optimisation du convertisseur, il est donc impératif de prendre en compte trois facteurs principaux : 1) l’évolution des topologies de conversion, 2) l’évolution des composants actifs et passifs et 3) l’intégration de puissance. La réunion de ces trois facteurs permettra ainsi la miniaturisation des convertisseurs statiques. Dans un premier temps, nous préciserons la démarche adoptée pour le dimensionnement d’un convertisseur en prenant en compte : les topologies actives, les filtres différentiels et le système de refroidissement. Les différents éléments qui composent le convertisseur sont décrits dans un langage informatique orienté objet. Des facteurs de performances seront également introduits afin de faciliter le choix des semi-conducteurs, des condensateurs et du dissipateur pour un convertisseur statique. Dans un deuxième temps, nous présenterons le fonctionnement d’une topologie multicellulaire DC/DC, isolée pour l’application proposée. Nous présenterons les avantages du couplage de différentes phases de ce convertisseur. Nous introduirons les différentes associations des cellules et leurs avantages, possibles grâce à l’isolement, comme la mise en série et en parallèle. Puisque la caractérisation des pertes des semi-conducteurs est essentielle pour le dimensionnement du convertisseur statique, nous proposerons deux approches : un modèle de simulation relativement simple et paramétré à l’aide de seules notices constructeurs ; et une méthode de mesure des pertes dans les semi-conducteurs qui est à la fois précise et compatible avec les composants les plus rapides. En ce qui concerne les composants magnétiques, une surface de réponse des matériaux ferrites sera présentée. Nous allons décrire, par le biais analytique et de simulation, des modèles pour la détermination du champ magnétique à l’intérieur du noyau et des ondulations de courant engendrés. Finalement, en profitant des modèles et des résultats obtenus dans les sections précédentes, nous montrerons le dimensionnement et la réalisation de chaque partie du convertisseur BBCU 100kHz / 10kW. Une perspective d’un design idéal est également présentée. / The electricity is taking a more important place in the embedded systems. The electricity is a very moldable form of energy, easy to transport and adjustable or transformed with a very low losses. The electrical energy, associated with power converters, is easier to control than hydraulic and/or pneumatic energies for example, allowing a finer regulation and a cost cutting of maintenance. The installed power in the avionic models is growing fast. With the increasing number of electronic loads, a more electrical aircraft with an AC network would include a large number of rectifiers AC/DC which will have to respect the quality standards. A solution for the reduction of the mass would be to prefer a HVDC network (High Voltage DC BUS). On the future more electrical aircrafts, the designers will be facing a HVDC/DC power conversion. This is the role of the unit called BBCU (Buck Boost Converter Unit). In our case of study, a distribution network in DC voltage (± 270Vdc) is connected to a security low-voltage network (28Vdc) which includes a bidirectional power exchanges achieving 10kW. The power converter for this connection gives new challenges for the power electronics in terms of reliability, safety, failure detection, efficiency and reduction of mass and cost. The design of the power converter needs to take into account for an optimal design. It is thus imperative to take into account three main factors: 1) the evolution of the power topologies 2) the evolution of the active and passive devices and 3) the power integration. The meeting of these three factors will allow the miniaturization of the power converters. At first, the adopted approach for designing power converters, taking into account the power topology, the differential filters and the cooling system are presented. The various elements which compose the power converter are described in an Object-Oriented Programming. The performance factors will be introduced to facilitate the choice of semiconductors, capacitors and heat-sinks. Secondly, the operation phases of a multicellular isolated DC/DC topology for the proposed application are presented. A discussion of the advantages of the magnetic coupling is also introduced. Thanks to the isolation, different associations of switching cells, series or/and parallel connection, are possible. Knowing the losses of power semiconductors is an essential step to design a power converter, thus two approaches are proposed: 1) a simulation model using a relatively simple model with the datasheets information; and 2) a losses measurement method which is precise and compatible with the fastest devices. As regards the magnetic components, a response surface of ferrite materials will be presented. Some models for the determination of the magnetic field inside the core and the current ripple are also described. Finally, by taking advantage of models and results obtained in the previous sections, the design and the realization of each party of the BBCU power converter 100kHz / 10kW is showed. A perspective of an ideal design is also presented.

Considerando condições anormais que o Sistema Elétrico de Potência (SEP) está sujeito, a proteção de seus elementos é um tópico importante. Dentre os equipamentos a serem protegidos, destacam-se os geradores devido a representarem elevado custo de investimento e estarem sujeitos a multas por paradas não programadas. Desta forma, com base em pesquisa bibliográfica, observa-se que não existem estudos abrangentes para a proteção individual de máquinas síncronas aplicadas à geração eólica. Além disso, considerando o contexto das smart grids, a presença de baterias e a possibilidade da operação ilhada podem alterar a dinâmica das situações de falta. Portanto, faz-se necessário um estudo do comportamento dos aerogeradores em situações de falha, sabendo que o esquema de proteção depende do tipo de gerador e da maneira como este está conectado ao SEP. Neste sentido, esta pesquisa propôs incluir uma bateria para operar com um gerador eólico de velocidade variável de forma complementar, suavizando a potência de saída e tornando o sistema de conversão de energia eólica forte o suficiente para operar no modo ilhado. A metodologia estabelece vários tipos de falhas para investigar o comportamento da turbina eólica em tais condições. Para realizar as simulações de falta, foi utilizado um simulador digital de tempo real (RTDS®). Com base nisso, um esquema composto por funções de proteção convencionais foi especificado e testado usando o software MATLAB®. Além disso, simulações em laço fechado foram realizadas com relés comercial e universal. Os resultados obtidos com o esquema proposto são bastante promissores. / Considering abnormal conditions to which the Electric Power System (EPS) may be subjected, the protection of its elements is an important topic. Among the equipments to be protected, the generators are highlighted, because they represent a high investment cost and are subjected to penalties for unscheduled stoppages. Hence, based on literature, it is observed that there are no comprehensive studies and standards for individual protection of Synchronous Generators (SGs) applied to Wind Energy Conversion System (WECS). Furthermore, considering the smart grids context, the presence of batteries and the possibility of island operation may change the dynamic of fault situations. Therefore, it is necessary to study and analyse the behavior of wind turbines in fault situations, knowing that the protection scheme is dependent on the generator type and the way it is connected to the EPS. In order to study these issues, this research proposed to include a battery to operate with a full-variable speed wind generator in a complementary way, smoothing the output power and making the WECS strong enough to operate in the island mode. The methodology establishes several fault types to investigate the wind turbine behavior in such conditions. In order to conduct the fault simulations, a real time digital simulator (RTDS®) was used. Based on this, a scheme composed by conventional protection functions were specified and tested using the MATLAB® software. Furthermore, hardware-in-the-loop simulations were performed with commercial and universal relays. Very good results in favor of the proposed scheme are presented.

Considerando condições anormais que o Sistema Elétrico de Potência (SEP) está sujeito, a proteção de seus elementos é um tópico importante. Dentre os equipamentos a serem protegidos, destacam-se os geradores devido a representarem elevado custo de investimento e estarem sujeitos a multas por paradas não programadas. Desta forma, com base em pesquisa bibliográfica, observa-se que não existem estudos abrangentes para a proteção individual de máquinas síncronas aplicadas à geração eólica. Além disso, considerando o contexto das smart grids, a presença de baterias e a possibilidade da operação ilhada podem alterar a dinâmica das situações de falta. Portanto, faz-se necessário um estudo do comportamento dos aerogeradores em situações de falha, sabendo que o esquema de proteção depende do tipo de gerador e da maneira como este está conectado ao SEP. Neste sentido, esta pesquisa propôs incluir uma bateria para operar com um gerador eólico de velocidade variável de forma complementar, suavizando a potência de saída e tornando o sistema de conversão de energia eólica forte o suficiente para operar no modo ilhado. A metodologia estabelece vários tipos de falhas para investigar o comportamento da turbina eólica em tais condições. Para realizar as simulações de falta, foi utilizado um simulador digital de tempo real (RTDS®). Com base nisso, um esquema composto por funções de proteção convencionais foi especificado e testado usando o software MATLAB®. Além disso, simulações em laço fechado foram realizadas com relés comercial e universal. Os resultados obtidos com o esquema proposto são bastante promissores. / Considering abnormal conditions to which the Electric Power System (EPS) may be subjected, the protection of its elements is an important topic. Among the equipments to be protected, the generators are highlighted, because they represent a high investment cost and are subjected to penalties for unscheduled stoppages. Hence, based on literature, it is observed that there are no comprehensive studies and standards for individual protection of Synchronous Generators (SGs) applied to Wind Energy Conversion System (WECS). Furthermore, considering the smart grids context, the presence of batteries and the possibility of island operation may change the dynamic of fault situations. Therefore, it is necessary to study and analyse the behavior of wind turbines in fault situations, knowing that the protection scheme is dependent on the generator type and the way it is connected to the EPS. In order to study these issues, this research proposed to include a battery to operate with a full-variable speed wind generator in a complementary way, smoothing the output power and making the WECS strong enough to operate in the island mode. The methodology establishes several fault types to investigate the wind turbine behavior in such conditions. In order to conduct the fault simulations, a real time digital simulator (RTDS®) was used. Based on this, a scheme composed by conventional protection functions were specified and tested using the MATLAB® software. Furthermore, hardware-in-the-loop simulations were performed with commercial and universal relays. Very good results in favor of the proposed scheme are presented.

Dans ce mémoire, nous avons étudié les convertisseurs d’interface permettant l’interconnexion d’une source basse tension non linéaire et d’un bus DC moyenne tension. La source choisie, pour l’étude, était une pile à combustible de type PEM. La structure de puissance retenue correspondant à la mise en cascade d’un convertisseur entrelacé en entrée et d’un convertisseur trois niveaux en sortie. Afin de dimensionner au mieux le convertisseur global, nous avons proposé un modèle analytique permettant de connaitre l’ensemble des pertes dans le système en fonction du point de fonctionnement et de ses paramètres. Nous avons montré que l’ensemble des pertes dans le convertisseur peut être modélisé par deux résistances non linéaires dont l’estimation est possible à partir des modèles moyens du convertisseur. Une commande basée sur le concept de platitude des systèmes différentiels a été utilisée pour assurer les différentes contraintes du système tout en obtenant des propriétés dynamiques élevées en asservissement et en régulation. Dans la dernière partie du mémoire, nous nous sommes intéressés aux solutions permettant de satisfaire les contraintes sur le taux d’ondulation de courant en entrée du convertisseur. Nous avons proposé et dimensionné une nouvelle structure de convertisseur permettant de supprimer les ondulations de courant générées par le convertisseur de puissance. Ce filtre actif se connecte en parallèle avec le convertisseur de puissance. Des résultats expérimentaux ont permis de montrer que le taux d’ondulation de courant d’un convertisseur élévateur a été réduit, le taux d’ondulation de courant passant de 23.3% à 1.9% / In this thesis, we studied interface converters enabling the interconnection of a low voltage nonlinear source and a medium voltage DC bus. The source selected for the study was a fuel cell PEM. The chosen power architecture corresponds to a cascaded structure constituted with an interleaved Boost converter at input stage and a three-level Boost converter at output stage. To design the converter, we proposed an analytical model to know the total losses in the system according to the operating point and its parameters. We showed that all losses in the converter can be modeled by two nonlinear resistors. An estimation of these resistors, deduced from average model of the converter, is developed. A control based on the concept of differential systems flatness has been used for the proposed converter structure. It allows taking into account the different system constraints. High dynamic properties as regard to external perturbations or parameters variations are achieved. In the last part of the thesis, we investigate solutions to respect the constraints on the rate of input current ripple. We propose a new active filtering converter connected in parallel with the power one. We have shown that the ripple current of a boost converter was reduced, the ripple current being reduced from 23.3% to 1.9%

Les systèmes piles à combustible de type PEM pour des applications de transport reposent sur un ensemble d’auxiliaires (stockage d’hydrogène, compresseur d’air, convertisseur de puissance, humidificateur, etc) qui assurent le bon fonctionnement du système pile. La mise en place d’observateurs permet de disposer d’un outil pour reconstruire les états non mesurés de ce système; cela permet de mettre en place un contrôle par retour de sortie en vue d’optimiser les performances du système pile et ainsi d'améliorer la détection et l’isolation de défauts (FDI). Cette thèse est basée sur l’étude et la synthèse d'observateurs adaptatifs par mode glissant d’ordre supérieur, pour deux principaux auxiliaires de la pile que sont, le système d'alimentation en air et les convertisseurs de puissance associés à la pile. La première partie de la thèse est consacrée à la synthèse d’observateurs pour la reconstruction des états et à la détection et l’isolation des défauts sur le système d’alimentation en air de la PEMFC. Dans un premier temps, un observateur algébrique par mode glissant d’ordre supérieur est synthétisé pour la reconstruction de la pression partielle de l'oxygène et de l'azote. Dans un deuxième temps, un nouvel observateur adaptatif par mode glissant d’ordre deux est synthétisé pour assurer l'observation simultanée des états, l'identification des paramètres, la surveillance et la reconstruction de défaut dans le circuit d’air. Les performances des observateurs proposées ont été validées grâce à un simulateur Hardware-In-Loop (HIL) du système pile à combustible.Dans la deuxième partie, nous nous sommes intéressés à l’élaboration d’observateurs et de commande par retour de sortie pour les convertisseurs associé au système pile dans une application transport. Ainsi, une commande novatrice par mode glissant d’ordre deux, de type retour de sortie, a été élaborée pour le convertisseur AC/DC. Dans un second temps, un observateur de type modes glissants d’ordre 2 adaptatif est synthétisé pour un convertisseur de type multicellulaire. / Automotive PEM Fuel Cell systems rely upon a set of auxiliary systems for proper operation, such as humidifier, air-feed compressor, power converter etc. The internal physical states of the latter are often unmeasurable, yet required for their precise control. Observers provide a means of obtaining the unmeasured states of these auxiliary systems for feedback control, optimal energy consumption and Fault Diagnosis and Isolation (FDI). This thesis is based on higher order sliding mode observer design studies for two major PEMFC auxiliary systems found in modern automobiles, the air-feed system and the power electronics system.The first part is focused on robust observation and FDI of the PEMFC air-feed systems. Sliding mode observer design and their applications to FDI have been studied in detail for this purpose and the key observation problems in this system have been identified. Based on this study, two solutions are proposed, a sliding mode algebraic observer for oxygen and nitrogen partial pressures and a novel robust adaptive-gain Second Order Sliding Mode (SOSM) observer based FDI for simultaneous state observation, parameter identification, health monitoring and fault reconstruction of the PEMFC air-feed system. The performance of the proposed observers has been validated on an instrumented Hardware-In-Loop (HIL) test bench.The observation and output feedback control problems of different power electronic converters, commonly found in fuel cell vehicles, are addressed in the next part. Robust output feedback SOSM control for three phase AC/DC converters have been presented. A robust SOSM observer for multi-cell converters has also been designed. The performance of all these designs has been demonstrated through a multi-rate simulation approach. The results highlight the robustness of the observers and controllers against parametric uncertainty, measurement noise and external disturbance.

L'intérêt pour les véhicules électriques ne cesse de croitre au sein de la société contemporaine compte tenu de ses nombreuses interrogations sur l’environnement et la dépendance énergétique. Dans ce travail de thèse, nous essayons d’améliorer l’acceptabtabilité sociétale du véhicule électrique en essayant de faire avancer la recherche sur le diagnostique des défauts d’une chaine de traction électrique. Les résultats escomptés devraient permettre à terme d’améliorer la fiabilité et la durabilité de ces systèmes.Nous commençons par une revue des problèmes des défauts déjà apparus dans les véhicules hybrides séries qui disposent de l’architecture la plus proche du véhicule électrique. Une étude approfondie sur le diagnostic des défauts d’un convertisseur de puissance statique (AC-DC) ainsi que celle du moteur synchrone à aimants permanents est menée. Quatre types de défauts majeurs ont été répertoriés concernant le moteur (court-circuit au stator, démagnétisation, excentricité du rotor et défaut des roulements). Au niveau du convertisseur, nous avons considéré le défaut d’ouverture des interrupteurs. Afin d’être dans les mêmes conditions d’utilisation réelle, nous avons effectué des tests expérimentaux à vitesse et charge variables. Ce travail est basé aussi bien sur l’expérimentation que sur la modélisation. Comme par exemple, la méthode des éléments finis pour l’étude de la démagnétisation de la machine. De même, l’essai en court-circuit du stator du moteur en présence d’un contrôle vectoriel.Afin de réaliser un diagnostic en ligne des défauts, nous avons développé un modèle basé sur les réseaux de neurones. L’apprentissage de ce réseau de neurone a été effectué sur la base des résultats expérimentaux et de simulations, que nous avons réalisées. Le réseau de neurones est capable d'assimiler beaucoup de données. Ceci nous permet de classifier les défauts en termes de sévérité et de les localiser. Il permet ainsi d'évaluer le degré de performance de la chaine de traction électrique en ligne en présence des défauts et nous renseigner ainsi sur l'état de santé du système. Ces résultats devraient aboutir à l’élaboration d’une stratégie de contrôle tolérant aux défauts auto-reconfigurable pour prendre en compte les modes dégradés permettant une continuité de service du véhicule ce qui améliorera sa disponibilité. / The interest in the electric vehicles rose recently due both to environmental questions and to energetic dependence of the contemporary society. Accordingly, it is necessary to study and implement in these vehicle fault diagnosis systems which enable them to be more reliable and safe enhancing its sustainability. In this work after a review on problem of faults in the drivetrain of series hybrid electric vehicles (SHEV), a deep investigation on fault diagnosis of AC-DC power converter and permanent magnet synchronous motor (PMSM) have been done as two important parts of traction chains in SHEVs. In other major part of this work, four types of faults (stator winding inter turn short circuit, demagnetization, eccentricity ant bearing faults) of a PMSM have been studied. Inter turn short circuit of stator winding of PMSM in different speeds and loads has been considered to identify fault feature in all operation aspects, as it is expected by electric vehicle application. Experimental results aiming short circuits, bearing and eccentricity fault detection has been presented. Analytical and finite element method (FEM) aiming demagnetization fault investigation has been developed. The AC-DC converter switches are generally exposed to the possibility of outbreak open phase faults because of troubles of the switching devices. This work proposes a robust and efficient identification method for data acquisition selection aiming fault analysis and detection. Two new patterns under AC-DC converter failure are identified and presented. To achieve this goal, four different level of switches fault are considered on the basis of both simulation and experimental results. For accuracy needs of the identified pattern for SHEV application, several parameters have been considered namely: capacitor size changes, load and speed variations. On the basis of the developed fault sensitive models above, an ANN based fault detection, diagnosis strategy and the related algorithm have been developed to show the way of using the identified patterns in the supervision and the diagnosis of the PMSM drivetrain of SHEVs. ANN method have been used to develop three diagnosis based models for : the vector controlled PMSM under inter turn short circuit, the AC/DC power converter under an open phase fault and also the PMSM under unbalanced voltage caused by open phase DC/AC inverter. These models allow supervising the main components of the PMSM drivetrains used to propel the SHEV. The ANN advantages of ability to include a lot of data mad possible to classify the faults in terms of their type and severity. This allows estimating the performance degree of that drivetrains during faulty conditions through the parameter state of health (SOH). The latter can be used in a global control strategy of PMSM control in degraded mode in which the control is auto-adjusted when a defect occurs on the system. The goal is to ensure a continuity of service of the SHEV in faulty conditions to improve its reliability.

Submitted by ALESSANDRO LUCINDO DA LUZ null (aledaluz@hotmail.com) on 2018-01-10T01:24:32Z No. of bitstreams: 1 Operacao flexivel conversores_ALuz.pdf: 10997918 bytes, checksum: 18fe1f6d3eba73d11bf63fab8cf0a0be (MD5) / Approved for entry into archive by Maria Marlene Zaniboni null (zaniboni@bauru.unesp.br) on 2018-01-10T11:41:48Z (GMT) No. of bitstreams: 1 luz_al_me_bauru.pdf: 10997918 bytes, checksum: 18fe1f6d3eba73d11bf63fab8cf0a0be (MD5) / Made available in DSpace on 2018-01-10T11:41:48Z (GMT). No. of bitstreams: 1 luz_al_me_bauru.pdf: 10997918 bytes, checksum: 18fe1f6d3eba73d11bf63fab8cf0a0be (MD5) Previous issue date: 2017-11-13 / Este trabalho de mestrado descreve uma estratégia de operação multifuncional e flexível aplicado a conversores trifásicos CC-CA (inversores) conectados à rede de distribuição de energia elétrica. A estratégia proposta é capaz de injetar potência ativa na rede e compensar correntes de distúrbios (reativos, desbalanço e harmônicos) simultaneamente. O maior objetivo desta operação flexível é de melhorar a Qualidade de Energia Elétrica em um ponto de acoplamento comum (PAC) permitindo a compensação total ou parcial destes distúrbios ou fatores que degradam a Qualidade de Energia Elétrica. O fator de potência é o principal fator de qualidade a ser observado e ele é calculado através da Teoria da Potência Conservativa – CPT. Entretanto, com base no fator de potência medido pelo lado da rede de distribuição e o fator de potência desejado, um coeficiente de compensação – k é calculado para o ajuste das correntes de compensação dos distúrbios que geram a potência não ativa. / This paper depicts a multifunctional and flexible control strategy applied in three-phase inverters, which are connected to the distribution network. The proposed strategy is able to inject active power into the electrical grid and compensate current disturbances (reactive, harmonics and unbalance) simultaneously. The main goal of this flexible strategy is to improve the Power Quality at the point of common coupling (PCC) allowing full or partial compensation of disturbances. Power factor is the main quality index observed and it is calculated according to Conservative Power Theory - CPT. Therefore, based on the power factor measured in the grid side and the desired value for the power factor, a compensation coefficient - k is calculated continuously adjusting the amplitude of the compensation current.

Ces travaux de thèse s’inscrivent dans la problématique de développement de transformateurs planar pour l’intégration de puissance, dans le contexte de l’avion plus électrique (More Electric Aircraft – MEA) où les contraintes de volume et de poids sont primordiales. Les composants magnétiques restent en effet un frein à l’intégration des systèmes d’Electronique de Puissance et les composants planar (transformateurs et inductances) offrent une alternative intéressante aux composants bobinés pour la réduction de la taille des convertisseurs.Dans ce manuscrit, des méthodes, un outil de dimensionnement et des prototypes de transformateurs planar (2 et 3 enroulements) en technologie feuillard et PCB sont développés pour des applications de convertisseur DC/DC aéronautique. Dans un premier temps, les modèles permettant le calcul des pertes, l'estimation de l'élévation de température et le calcul de l’inductance de fuite sont présentés et comparés afin de concevoir des outils de calculs pour la conception. Dans un deuxième temps, il est montré que la modification de la forme des angles des spires rectangulaires permet de réduire significativement les pertes cuivre HF. Sur la base de ces outils et résultats, des prototypes de transformateurs planar à 3 enroulements en PCB multicouches sont développés. De nombreux prototypes sont caractérisés et valident les modèles de dimensionnement proposés. Enfin, l’un de ces prototypes est intégré et testé dans un convertisseur de puissance DC/DC de 3.75kW mettant en évidence les gains obtenus. / These thesis works deal with the issue of the planar transformers development for power integration, in the context of the More Electric Aircraft (MEA), where the constraints of volume and weight are paramount. Magnetic components remain a hindrance to the integration of Power Electronics systems and planar components (transformers and inductors) offer an interesting alternative to wound components for reducing the size of converters.In these works, methods, a sizing tool and prototypes of planar transformers (2 and 3 windings) in strip and PCB technology are developed for aeronautical DC / DC converter applications. Firstly, the models allowing the calculation of the losses, the estimation of the temperature rise and the calculation of the leakage inductance are presented and compared in order to design calculation tools for engineers. In a second step, it is shown that the modification of the shape of the angles of rectangular turns makes it possible to significantly reduce the HF copper losses.Based on these tools and results, prototypes of 3-windings planar transformers in multilayer PCBs are developed. Many prototypes are characterized and validate the proposed designing models. Finally, one of these prototypes is integrated and tested in a DC / DC power converter of 3.75kW highlighting the gains obtained.