Είναι γνωστό ότι τα κυκλώματα των τελεστικών ενισχυτών (Op-Amps) είναι από τις βασικότερες δομικές βαθμίδες στον χώρο της σχεδίασης αναλογικών ολοκληρωμένων κυκλωμάτων. Μια εναλλακτική δομή του τελεστικού ενισχυτή αποτελεί το κύκλωμα ενός Current Feedback Operational Amplifier (CFOA). Ένας CFOA είναι ουσιαστικά ένας μεταφορέας ρεύματος (Current Conveyor-CCII) σε σειρά με έναν ακολουθητή τάσης (Voltage Follower), και είναι ιδιαιτέρως χρήσιμος κατά την σχεδίαση κυκλωμάτων χαμηλής τάσης τροφοδοσίας. Στην εργασία αυτή μελετήθηκαν τέσσερις δομές CFOA, σχεδιασμένες για λειτουργία με χαμηλή τάση τροφοδοσίας, και χρησιμοποιήθηκαν για τον σχεδιασμό φίλτρων με τις μεθόδους Leapfrog, τοπολογικής εξομοίωσης και κυματική. Στο πρώτο κεφάλαιο αναφέρονται οι γενικές αρχές που ισχύουν στην σχεδίαση κυκλωμάτων για λειτουργία με χαμηλή τάση τροφοδοσίας καθώς και τις πιο συχνά χρησιμοποιούμενες τεχνικές σχεδίασης. Στο δεύτερο κεφάλαιο μελετώνται αναλυτικά οι τέσσερις δομές CFOA συγκρίνοντας τους βασικότερους παράγοντες απόδοσής τους. Τα κυκλώματα των CFOA που μελετώνται βασίζονται σε πρόσφατα δημοσιευμένες δομές Current Conveyor (CCII). Στο τρίτο κεφάλαιο αναλύεται η μέθοδος σχεδίασης φίλτρων Leapfrog, και χρησιμοποιείται για την σχεδίαση ενός Butterworth φίλτρου 3ης τάξης. Ως δομική βαθμίδα για την σχεδίαση αυτού του φίλτρου χρησιμοποείται ο CFOA [2]. Το τρίτο κεφάλαιο ολοκληρώνεται με την παρουσίαση των βασικότερων παραγώντων απόδοσης. Στο τέταρτο κεφάλαιο παρουσιάζεται η τοπολογική μέθοδος σχεδίασης φίλτρων, στην οποία γίνεται τοπολογική αντικατάσταση πηνίου, σε παθητικό φίλτρο, από ισοδύναμο κύκλωμα με ενεργά στοιχεία. Και στην περίπτωση αυτή η δομική μονάδα σχεδιασμού είναι ο CFOA [2]. Στο πέμπτο κεφάλαιο παρουσιάζεται η σχεδίαση ενός Butterworth φίλτρου 3ης τάξης με την κυματική μέθοδο. Η σχεδίαση πραγματοποιήθηκε χρησιμοποιώντας ως δομική βαθμίδα τον CFOA [1]. Στο έκτο κεφάλαιο παρουσιάζεται η φυσική σχεδίαση (layout) του Butterworth φίλτρου 3ης τάξης που σχεδιάστηκε με την leapfrog μέθοδο στο τρίτο κεφάλαιο. Η φυσική σχεδίαση πραγματοποιήθηκε με την χρήση του λογισμικού Cadence και του περιβάλλοντος Virtuoso που περιλαμβάνει για την φυσική σχεδίαση αναλογικών ηλεκτρονικών κυκλωμάτων . Τέλος στο έβδομο κεφάλαιο γίνεται σύγκριση των αποτελεσμάτων εξομοίωσης των δομών CFOA’s αλλά και των αποτελεσμάτων εξομοίωσης των φίλτρων που σχεδιάστηκαν στα παραπάνω κεφάλαια . Επίσης παρουσιάζονται κάποιες προτάσεις για μελλοντική και περαιτέρω έρευνα. / Operational amplifier is one of most important analog building block. An alternative structure for operational amplifier is a Current Feedback Operational Amplifier (CFOA). A CFOA is essentially consists of a current conveyor (CCII) connecting with a Voltage Follower (VF). The usage of CFOA for the low-voltage analog IC design is quite useful. In this work four different CFOA structures, designed for low-voltage operation, were considered. Also the aforementioned CFOAs were used to build a butterworth filter with Leapfrog method, topological simulation method and wave method. In first chapter the basic design rules and the most common design techniques for low-voltage IC design is presented. In chapter 2 the four structures of CFOAs circuits were considered, under the light of comparison of most critical factors of operation. The CFOAs circuits were based in most resent published topologies of Current Conveyor (CCII). In chapter 3 the Leapfrog method for filters design was discussed. Also a 3rd order butterworth filter is designed based on this method. The CFOA of ref [2] is the main building lock to construct this filter. In chapter 4 another method for filter design is presented named topological simulation method. According to this method passive elements such as inductors and capacitors are replaced by active elements. The main building block is also CFOA of ref [2]. In Chapter 5 a 3rd order butterworth filter based on wave method is designed. In this case the main building block was the CFOA circuit of ref [1]. Chapter 6 presents the layout of the 3rd order butterworth filter which designed at chapter 3 with leapfrog method. The layout design was implemented using Virtuoso environment of Cadence design framework II platform. Chapter 7 conclude this work presenting the simulated comparison results for all four CFOAs circuits and the 3rd order butterworth filters that were designed with the three different methods. Some thoughts for further research in the this subject are also presented.

Οι συνεχώς αυξανόμενες ανάγκες της σημερινής αγοράς για φορητές ηλεκτρονικές συσκευές και τηλεπικοινωνιακά συστήματα χαμηλής τάσης τροφοδοσίας και χαμηλής κατανάλωσης ισχύος, καθιστά απαραίτητη τη σχεδίαση ενεργών βαθμίδων οι οποίες θα είναι ικανές να λειτουργήσουν σε ένα περιβάλλον όπου μία απλή τάση τροφοδοσίας μικρότερη ή ίση με 1.5V είναι διαθέσιμη. Έτσι, στην εργασία αυτή θα γίνει μια μελέτη διαφορετικών ενεργών βαθμίδων που δύνανται να λειτουργήσουν στο περιβάλλον αυτό, συγκρίνοντας τις δυνατότητες τους. Η μελέτη αυτή αφορά στις ενεργές βαθμίδες CCII και CFOA, καθώς και σε παραλλαγές τους που αφορούν στη λειτουργία των βαθμίδων αυτών με διαφορική τάση εισόδου (DVCCII και DVCFOA).Απώτερος σκοπός της σύγκρισης των βαθμίδων αυτών, αποτελεί η εφαρμογή τους στη σχεδίαση και υλοποίηση μιγαδικών φίλτρων. Έτσι, έπειτα από μία πλήρη περιγραφή των μιγαδικών φίλτρων ώστε να κατανοηθεί η λειτουργία τους, αλλά και των προβλημάτων που εισάγουν την ανάγκη χρήσης τέτοιων φίλτρων, θα μελετηθεί η χρησιμότητα καθεμιάς από τις παραπάνω ενεργές βαθμίδες στη σχεδίαση μιγαδικών φίλτρων ανώτερης τάξης, τα οποία πληρούν τις προδιαγραφές της εκάστοτε τεχνολογίας. Συγκεκριμένα θα γίνει η σχεδίαση και υλοποίηση ενός μιγαδικού φίλτρου 12ης τάξης ικανού να λειτουργεί (κατ’ επιλογή) τόσο για ένα κανάλι μετάδοσης μέσω του πρωτοκόλλου Bluetooth, όσο και για ένα κανάλι μετάδοσης μέσω του πρωτοκόλλου ZigBee.Τελικό βήμα της εργασίας, αποτελεί η φυσική σχεδίαση του κυκλώματος που θα προκύψει, ώστε να επαληθευτεί η ορθή λειτουργία του σε ένα περισσότερο ρεαλιστικό περιβάλλον. / The ever-increasing needs of today's market for portable electronic devices and telecommunication systems of low voltage and low power consumption, necessitates the design of active building blocks that are likely to operate in an environment where a single supply voltage less than or equal to 1.5V is available. Thus, this work will be a study of different active building blocks that may operate in this environment, comparing their abilities. The study refers to active building blocks CCII and CFOA, as well as variations related to their operation involving differential input voltage (DVCCII and DVCFOA). The ultimate goal of comparing these blocks is their application in the design and implementation of complex filters. Thus, after a full description of complex filters to understand their functioning and the problems that introduce the need to use such filters, the usefulness of each of these blocks will be studied in the design of higher-order complex filters, which meet the specifications of each technology. In particular a 12th order complex filter able to function (optional) for both a transmission channel over Bluetooth Protocol, and a transmission channel over ZigBee Protocol, will be designed and implemented. Final step of the work is the physical layout of the circuit, so as to verify the proper functioning in a more realistic environment.

Στην παρούσα διπλωματική εργασία εκπονείται μελέτη που αφορά την σχεδίαση αναλογικών ηλεκτρονικών κυκλωμάτων για βιοϊατρικές εφαρμογές. Δίνεται μεγαλύτερη βαρύτητα στην υλοποίηση διαγωγών χαμηλής τροφοδοσίας και ενισχυτών ρεύματος οδηγούμενων από το υπόστρωμα. Όπως σε όλα τα διαφορικά κυκλώματα, έτσι και στους διαφορικούς διαγωγούς κύριο μέλημα των σχεδιαστών είναι η γραμμικότητα τους και οι παράμετροι που την επηρεάζουν. Προτείνεται ένας διαγωγός χαμηλής τροφοδοσίας που βασίζεται στην βαθμίδα ακόλουθου τάσης με αναστροφή και προσομοιώνεται για να μελετηθεί το εύρος της γραμμικότητας του, η απόκριση συχνότητας και η συμπεριφορά του σε χρονικά μεταβαλλόμενο ημιτονοειδές σήμα. Ο ενισχυτής ρεύματος οδηγούμενος από το υπόστρωμα που παρουσιάζεται σε αυτήν την εργασία εκμεταλλεύεται όλους τους βαθμούς ελευθερίας ενός MOS τρανζίστορ πολωμένου στην ασθενή αναστροφή και στον κόρο. Η τεχνική οδήγησης από το υπόστρωμα χρησιμοποιείται ευρέως στην σχεδίαση κυκλωμάτων χαμηλής τροφοδοσίας, αφού έχει μειωμένες απαιτήσεις τάσης, ενώ είναι και ανεξάρτητη από περιορισμούς σχετικούς με την τάση κατωφλίου. Επιπρόσθετα, τα τρανζίστορ με οδήγηση από το υπόστρωμα διατηρούνται στην περιοχή κόρου για αρνητικές, μηδενικές και σχετικά μικρές θετικές τιμές της τάσης πόλωσης VBS. Έτσι, μπορούν να επεξεργάζονται σήματα εισόδου κοινού τρόπου (common-mode input range) μεγάλης τιμής και με μεγάλο εύρος κυμάτωσης κάτι που δεν θα μπορούσε να επιτευχθεί με συμβατικές κυκλωματικές τεχνικές σε τόσο χαμηλή τάση τροφοδοσίας. Όμως, τα τρανζίστορ με οδήγηση από το υπόστρωμα έχουν μικρή τιμή διαγωγιμότητας και είναι ευαίσθητα στον θόρυβο. Άλλο μειονέκτημα της τεχνικής με οδήγηση από το υπόστρωμα είναι ότι η πόλωση των τρανζίστορ εξαρτάται από την τεχνολογία ολοκλήρωσης. Το κέρδος του ενισχυτή ρεύματος οδηγούμενου από το υπόστρωμα μεταβάλλεται με εκθετικό τρόπο. Αυτή η ιδιότητα είναι σημαντική και χρησιμοποιείται ευρέως σε συστήματα αυτομάτου ελέγχου κέρδους όπου το σήμα εισόδου μεταβάλλεται αρκετές τάξεις μεγέθους. Σε ένα παρόμοιο σύστημα χρησιμοποιούμε και τα προαναφερθέντα κυκλώματα και εξετάζουμε την συνολική συμπεριφορά του. Οι προδιαγραφές αυτών των κυκλωμάτων επιτρέπουν την εφαρμογή τους στην βιοϊατρική, αφού εμφυτεύσιμα συστήματα, βίο-αισθητήρες και βοηθητικά ακοής επεξεργάζονται σήματα σχετικά χαμηλών συχνοτήτων με χαμηλή τάση τροφοδοσίας. / This diploma thesis forms a study on the design of analog circuits for biomedical applications. We focus on the realization of low voltage transconductors and Bulk-Driven current amplifiers. Like all the differential circuits, the designers’ main concern for a differential transconductor is its linearity and the parameters that affect it. We propose a low voltage transconductor based on Flipped Voltage Follower topology and we simulate it in order to study the range of the linearity, frequency response and its behavior in temporally varying sinusoidal signal. The Bulk-Driven current amplifier presented in this thesis takes advantage of all degrees of freedom of a MOS transistor biased in weak inversion and in saturation. The Bulk-Driven technique is widely used in the design of low voltage supply, because it has reduced demands on voltage and is independent of restrictions related to the threshold voltage. Moreover, Bulk-Driven transistors are maintained in saturation for negative, zero and even small positive values of the bias voltage VBS. Consequently, they can process large input common mode signals and signals with large swing voltage range, a property that could not be achieved with conventional circuit techniques at low power supply voltages. However, the transconductance of a Bulk –Driven transistor is smaller and is sensitive to noise. Another disadvantage of the Bulk-Driven technique is that the polarity of the transistor is process related. The gain of the Bulk-Driven current amplifier varies exponentially. This property is important and it is used widely in systems of automatic gain control where input signals can range several orders of magnitude. The specifications of these circuits allow their appliance in biomedicine, because implanted systems, biosensors and hearing aids process signals of relatively small frequencies with low voltage supply.

Os métodos convencionais para o controle de tensão concentram-se na média tensão. Em alguns casos não são suficientes para a correção da tensão na rede secundária. Este trabalho apresenta os problemas relacionados à regulação de tensão na baixa tensão, os métodos convencionais para correção da tensão e uma estratégia para o controle de tensão na rede secundária de sistema de distribuição de energia elétrica. A solução final proposta é um conjunto de transformador com taps no lado de baixa tensão, hardware e software que promovem a comutação das derivações do transformador de forma automática. Para o desenvolvimento dessa estratégia será abordada a aplicação de sistemas inteligentes, o sistema fuzzy, e a estimação de modelos elétricos dos transformadores de distribuição. O objetivo desse produto é ser uma solução prática, viável técnica e economicamente para a regulação da tensão em cenários onde os métodos convencionais não o são. Os protótipos dessa solução foram montados e testados em laboratório e em campo e os resultados atenderam ao objetivo proposto. / The conventional methods for voltage control concentrated in medium voltage. In some case, they are not enough to correct the voltage on secondary grid of distribuition. This paper presents a strategy to control the voltage on the low voltage of the distribution grid. As proposed for dealing of this problem is made the presentation of an architecture for the intelligent automatic control, that is composed of distribuition transformer with tap on the low side, hardware and software. For the development of this strategy will be approached the application the intelligent systems, Fuzzy Systems, and the estimation of electrical model of distribuition transformers. The goal with this design is to provide grants to set up a system for regulating the voltage on the low side which is technically and economically feasible to be deployed where conventional solutions, with the inclusion of line regulators, are not.

Orientador: Teófilo Miguel de Souza / Resumo: Esta Tese de Doutorado apresentou o estudo dos problemas de tensão originados no ponto comum de conexão de uma rede experimental para fornecer até 1.000 kWh/mês de energia solar com a rede de baixa tensão da Universidade de Ibagué, na Colômbia. Inicialmente foi feita uma introdução, onde destacou-se a importância da geração distribuída, os problemas gerados e os objetivos propostos. Em seguida, foi realizado o estudo da qualidade da energia na rede de baixa tensão, conforme as normas NTC 5001. Foi dimensionada, montada e colocada em operação uma rede experimental, utilizando a metodologia proposta nesta Tese, composta de 30 painéis solares de 260 W marca IBC solar, um inversor marca Fronius de 7,6 kW e um contador bidirecional ligados diretamente à rede através com fio de seção transversal de 6,0 mm2. A energia máxima produzida pela rede experimental foi de 850 kWh/mês, equivalente a 72,65% do total da capacidade instalada. Os painéis solares apresentaram uma eficiência média de 15,7%, a eficiência do inversor foi obtida na faixa de 75 a 94% e o desempenho global, PR, entre 0,83 e 1,30. Depois de avaliar a rede experimental seguiu-se com a análise da qualidade da energia no ponto comum de ligação registrando, em relação às perturbações de longa duração, um aumento de 2%; o desequilíbrio da tensão diminuiu 3,5%, as harmônicas de tensão aumentaram 7% na linha U1, 0,8% na linha U2 e 3% na linha U3. Em relação à corrente harmônica foi evidenciado um incremento de 22% na linha U1.... (Resumo completo, clicar acesso eletrônico abaixo) / Doutor

Orientador: Antonio Padilha Feltrin / Resumo: Este trabalho apresenta uma proposta de estratégia global de controle de tensão que emprega programação não linear e duas extensões de estratégias de controle de tensão, encontrados na literatura. O principal objetivo destas estratégias é solucionar o problema de aumento de tensão nas redes de distribuição de baixa tensão, causado pela injeção de potência do gerador fotovoltaico distribuído. Estas estratégias de controle de tensão foram implementadas e analisadas a fim de verificar a sua eficácia e comparar os seus comportamentos. Para os testes, foram considerados a operação de geradores fotovoltaicos monofásicos e trifásicos distribuídos em um sistema teste de distribuição em baixa tensão. Os resultados mostraram que depois da aplicação das estratégias de controle, os perfis de tensão em regime permanente ficaram dentro da faixa de tensão permitida, obtendo-se uma mínima redução de potência ativa injetada dos geradores fotovoltaicos com os seus correspondentes fatores de potência. / Abstract: This work presents a proposal of a global voltage control strategy that use nonlinear programming and two extensions of voltage control strategies that are found in the literature. The main objective of these strategies is to solve the problem of voltage increase in low voltage distribution networks, caused by the power injection of the distributed photovoltaic generator. These voltage control strategies have been implemented and analyzed in order to verify their effectiveness and compare their behaviors. For the test, the operation of single-phase and three-phase photovoltaic generators distributed in a low voltage distribution test system were considered. The results showed that after the application of the control strategies, the steady-state voltage profiles were whihin the allowed voltage range, obtaining a minimum reduction of the active power injection of the photovoltaic generators with their corresponding powe factors. / Mestre

La consommation d'énergie augmente d'année en année en raison de la croissance de la population et des conditions économiques. Afin de répondre aux besoins de la population et de la société d'utiliser l'électricité, le Gouvernement Cambodgien a mis en place la politique de promotion et d'encouragement du développement de l’électrification ; tous les villages auront de l'électricité d'ici 2020 et au moins 70% des domiciles auront accès à la bonne qualité du réseau électrique d'ici 2030. Pour réussir ces objectifs, l'étude et le développement de la méthodologie du réseau de distribution basse tension (BT) sont étudiés. Cette thèse étudie la planification du réseau de distribution BT avec intégration de Photovoltaïque (PV) et de stockage d’énergie de batterie (BES). La première partie est développée la méthode de planification à long terme pour tacler le défi de l'incertitude sur la charge en zone urbaine ;le nouvel algorithme a été développé pour rechercher l'architecture optimale de minimisation du coût d’investissement (CAPEX) et d’exploitation (OPEX) qui respecte l'ensemble de contraintes topologies et électriques (courant et tension) grâce à la programmation linéaire mixte en nombres entiers à contraintes quadratiques (PLMNECQ), le plus court chemin , first-fit bin-packing, et la méthode de Monte-Carlo. La deuxième partie est traité de l'extension de la zone de couverture de l'électricité avec deux solutions possibles, sont le renforcement du réseau et l'intégration de PV-BES pour le village rural ; l'algorithme génétique (GA) et la technique itérative ont été codés pour rechercher l’emplacement et la capacité. La dernière partie du travail est concentrée sur la planification du réseau de distribution résidentielle BT pour les zones non électrifiées aux rural et urbain grâce à l'architecture optimale et l'intégration de PV-BES sur l'horizon de planification. / The energy consumption is increasing year by year due to the growth of population and the economic conditions. In order to meet the need of population and society to use electricity, the Cambodian government has established the policy to promote and encourage the development of electrification; all the villages will have electricity by the year 2020, and at least 70% of households will have access to grid quality by the year 2030. To achieve these goals, the study and development of methodology on the Low-Voltage (LV) distribution system are investigated. This thesis studies the planning of LV distribution system with integration of Photovoltaic (PV) and Battery Energy Storage (BES). The first part is developed the long-term planning method to tackle the challenge of load demand uncertainty in urban area; the novel algorithm was developed to search for the optimal architecture of minimizing the capital expenditure (CAPEX) and the operation expenditure (OPEX) which respects to the set of topology and electrical (current and voltage) thank to mixed integer quadratically constrained programming (MIQCP), shortest-path, first-fit bin-packing, and Monte-Carlo method. The second part is dealt with the extension of electricity coverage area with two possible solutions which are grid reinforcement and integration of PV-BES for rural village; the Genetic algorithm (GA) and iterative technique were coded to search for location and sizing. The last part is concentrated on the planning of residential low-voltage distribution system in both rural and urban for non-electrified area thanks to the optimal architecture and PV-BES integration over the planning horizon.

Les îles Galápagos sont un archipel d'îles volcaniques situées dans l'océan Pacifique, à 926 km à l'ouest de l'Equateur continental, dont elles font partie. Depuis 1978, les îles Galápagos sont déclarées patrimoine mondial. En raison de la croissance de la population, il existe plusieurs problèmes sociaux, économiques et environnementaux qui risquent la conservation de l'environnement des îles. Dans ce contexte, le gouvernement équatorien veut préserver son patrimoine écologique. Par conséquence, avec la participation de divers acteurs, principalement le ministère de l'Énergie et des Énergies renouvelables, il effectue plusieurs initiatives. Afin d'améliorer les services fournis sur les îles, cet objectif sera accompli grâce à la réduction de la consommation de carburants fossiles et donc des émissions de CO2. Donc, cette thèse a analysé l'impact des nouveaux services sur le réseau électrique, comme le remplacement obligatoire des véhicules conventionnels et des cuisinières pour des solutions efficaces et la proposition des solutions pour réduire les problèmes négatifs sur le réseau. En outre, une forte intégration de la génération distribuée a été considérée dans l'analyse. De plus, des solutions innovantes pour basse et moyenne tension ont été conçues et testées afin d’améliorer le service électrique sans affecter l'environnement et conserver ce patrimoine mondial. Par exemple, un programme DSM intelligent composé d'un schéma de temps d'utilisation (TOU) combiné avec la réponse de la demande (DR) a montré des résultats intéressants, l'installation d'un système de stockage d'énergie de batterie a également été testée, et les résultats de moyenne tension sont prometteurs. Un système de commutation automatique de phase a été adapté comme une solution pour réduire le déséquilibre en basse tension avec des résultats impressionnants. Le déploiement des réenclencheurs a démontré une amélioration considérable de la fiabilité avec un retour d’investissement très court. Considérant les technologies de l'information et de la communication, une pièce clé pour déployer Smart Grids, l'architecture de communication des réseaux de NAN/FAN/HAN a été abordée. Enfin, un Système de Gestion d’Energie pour la gestion optimale de l'énergie à Galápagos a été conçu. Toutes ces études représentent un défi important : la gestion optimale de l'électricité de réseau isolée sans énergie fossile. / The Galápagos Islands are an archipelago of volcanic islands located in the Pacific Ocean, 926 km west of continental Ecuador, of which they are a part. Since 1978, Galapagos Islands are accepted as Heritage World, due to the growth of the population, there are several social, economic and environmental problems, which endanger the environment conservation of the Islands.In this context, the Ecuadorian government desires to preserve its ecological heritage. Hence, with the participation of several stakeholders mainly the Ministry of Energy and Renewable Energy, it is releasing a lot of initiatives. In order to improve the general services that are provided in the islands, this goal will be achieved by means of reducing fossil fuel consumption and therefore CO2 emissions. Thus, this thesis has analyzed the impact of new services on the grid such as the mandatory replacement of conventional vehicles and cookers for efficient ones and to propose solutions for reducing negative issues originated on the network. Also, a strong integration of distributed generation is considered in the analysis.In addition, innovative solutions for both low and medium voltage have been designed and tested for improving the electrical service without affecting the environment and conserving this world heritage. For instance, a smart DSM program composed of Time of Use scheme combined with Demand Response has shown interesting results, the installation of a Battery Energy Storage System has been studied as well; the results in Medium Voltage are promising. An Automatic Phase Switching system is adapted like a solution for reducing unbalance in low voltage with impressive results. The deployment of reclosers has demonstrated a considerable improvement in the reliability with a Return on Investment very short.Considering the Information and Communication Technologies a key piece to deploy Smart Grids, the communication architecture of the Neighbor, Field and Home Area Networks is addressed. As last, an Energy Management System for performing optimal energy management within Galapagos is designed. All these studies have a significant challenge: the optimal management of electricity of isolated grid with zero fossil energy.

L’ouverture des marchés de l’énergie et les nouveaux usages ont induit à des changements significatifs sur les réseaux de distribution (le réseau basse tension – BT – notamment), comme : l’augmentation des interconnections de production à partir de sources d’énergies renouvelables (EnR), l’accroissement de la pointe de consommation, entre autres. Ces derniers créent des contraintes électriques. Dans l’optique d’une gestion pragmatique des réseaux électriques intelligents, des gisements de flexibilité comme le pilotage des charges/sources ou le stockage sont recherchés pour offrir des nouvelles solutions à ces contraintes. Cette thèse étudie ainsi les enjeux de la gestion du stockage et son impact dans les méthodes de planification des réseaux BT. Ainsi, dans un premier temps, les impacts du stockage et de la production photovoltaïque sur des grandeurs utilisées dans la planification des réseaux de distribution sont étudiés. Dans un second temps, une méthode de calcul des coûts des pertes est adaptée à la présence du stockage et/ou de la production PV. Dans une dernière partie, des algorithmes de fonctions avancées de conduite sont développés afin d’illustrer la valeur économique du stockage dans la planification des réseaux BT, et comparés à une planification classique plus couteuse. / The opening up of energy markets and new uses have led to significant changes in distribution grids, in particular low-voltage grids. Notably, it has led to an augmentation in the integration of renewable energy production, an increase in the peak consumption, among others. This is accompanied by the appearance of the electrical constraints with which power systems must cope. This has resulted in the development multiple flexibility capabilities such as load/source management or energy storage, providing new solutions, now to be considered in planning methods. This thesis studies the issue of energy storage in the low-voltage grid planning. The first part of this thesis studies the impact of storage and photovoltaic production on variables involved in distribution grid planning. In the second part, a method for calculating the cost of losses is adapted to the presence of energy storage and/or PV production. Finally, advanced d operation algorithms are developed to illustrate the economic value of energy storage in LV distribution grid planning, compared to a more expensive conventional planning method.

Conselho Nacional de Desenvolvimento Científico e Tecnológico / This thesis addresses the main issues regarding the operation of full power converters wind turbines connected to the grid under balanced and unbalanced voltage sags. In the past, the grid codes allowed wind turbines to be disconnected during voltage and frequency disturbances. However, recently, grid codes updates often require that wind turbines remain connected during voltage sags aiming to provide voltage back-up support. Furthermore, some specific criteria establish that wind turbines should be able to utilize part of its current capability to promote the voltage back-up during unbalanced voltage sags. To guarantee the grid connected converter operation, even with voltage sags that lead to zero-voltage situations and unbalanced voltage conditions, a synchronous frame PLL with a very low time constant is designed and adapted with a Kalmam filter synchronization system. This thesis propose a two stages synchronization for grid connected converters that is able to ensure proper operation of the converter even when voltage on the converter terminals has temporarily falling down to zero. This goal is meet with a synchronous frame PLL with a very low time constant adapted with a Kalmam filter synchronization system. This composed synchronization system allows the converter control system to get the positive and negative sequences voltages components, that are necessary to the output power control even under severe voltage dips. Moreover, an anti windup is adapted to operate with a resonant current controller enabling the minimization of the saturation in the control action during voltage transients. During unbalanced voltage dips, the injection of unbalanced currents to the voltage back-up support becomes a good alternative to reduce the imbalance factor of the grid voltages. However, it is necessary to limit the maximum current output of the converter to avoid undesirable protection trips. This thesis proposes a strategy that limite the output currents allowing the use of the converter full current capacity during unbalanced voltage sags support. To achieve this goal, the current references are divided into three parts. The former is associated with the active power reference synchronized with the positive sequence voltage. The second is the reactive power synchronized with the positive sequence voltage and the third is the reactive power synchronized with the negative sequence voltage. The strategy propose the computation of th reactive power references by the positive and negative sequence voltages on the PPC in order to not overpass the converter current limits. Experimental and simulation results corroborate the contributions of this thesis. / Esta tese trata do problema de operação de aerogeradores com conversores plenos conectados à rede durante afundamentos de tensão equilibrados e desequilibrados. Inicialmente, os códigos de rede permitiam a desconexão dos aerogeradores durante distúrbios de frequência ou durante afundamentos de tensão. Entretanto, a presente tendência dos requisitos de conexão em diversos países obriga os aerogeradores a permanecerem conectados a contribuição destes com injeção de corrente reativa visando dar suporte à tensão. Além disso, alguns critérios especifícos estabelecem que aerogeradores devem ser capazes de utilizar parte de sua capacidade de corrente para promover o suporte de reativos também durante afundamentos desequilibrados. Nesta tese é apresentado um método de sincronismo composto baseado em filtro de Kalman e aplicado para conversores conectados à rede durante afundamentos de tensão que possam levar a tensão a zero no ponto de conexão. Este possibilita a obtenção das componentes de sequência e as suas tensões em quadratura de maneira simples, além de apresentar um bom desempenho dinâmico durante afundamentos desequilibrados. Além disso, uma estrutura anti windup é adaptada para operar com um controlador ressonante de corrente possibilitando a minimização da saturação da ação de controle na síntese das correntes de saída. Uma vez que o conversor do lado da rede é capaz de operar em condições severas de maneira adequada, a injeção de corrente reativa de forma a minimizar a tensão se sequência negativa no ponto de conexão é uma possibilidade para a diminuição do fator de desequilíbrio. Entretanto é necessário limitar as correntes máximas de saída do conversor. Esta tese propõem uma estratégia de limitação de corrente para conversores conectados à rede que possibilita o uso da plena capacidade de corrente do conversor na injeção de correntes desequilibradas para o suporte de tensão. Para atingir esse objetivo, as referências de corrente são dividas em três partes e com objetivos distintos. A primeira é associada a potência ativa sincronizada com a tensão de sequência positiva. A segunda representa a parcela de potência reativa sincronizada com a tensão de sequência positiva e a terceira parcela representa a potência reativa sincronizada com a tensão de sequência negativa. Pelo cômputo da norma máxima das correntes por uma expressão genérica é possível determinar as correntes de referência que respeitam os limites de corrente do conversor. Resultados de simulação e experimentais corroboram as contribuições desta tese.