In this thesis, a system to locate an electrostatic discharge (ESD) event within an electronic device has been developed. ESD can cause a device to fail legally required radiated emissions limits as well as disrupt intended operation. The system used a fast oscilloscope with four channels, each channel attached to a high frequency near-field antenna. These antennas were placed at known locations in three dimensional space to measure the fields radiated from the ESD event. A Time-Difference-of-Arrival technique was used to calculate the location of the ESD event. Quick determination of the ESD event location provides developers with a tool that saves them time and money by eliminating the time-consuming and tedious method of general ESD mitigation within a product.

Σε αυτή την εργασία ερευνήθηκε λεπτομερώς η ηλεκτρομαγνητική συμβατότητα (EMC) και η ασφάλεια ενός Φ/Β συστήματος. Τα συμπεράσματα από αυτές τις έρευνες θα συμβάλουν στη βελτίωση ή/και τη δημιουργία προτύπων σχετικά με την EMC και την ασφάλεια των συστημάτων . Τα κύρια θέματα που καλύπτονται από την εργασία είναι - έρευνες σχετικά με το ηλεκτρομαγνητικό περιβάλλον (π.χ. επίδραση από κεραυνό, μετρήσεις στο δίκτυο χαμηλής τάσης και υπερτάσεις) - έρευνες όσον αφορά τις εκπομπές (παρεμβολές στη περιοχή ραδιοφωνικών συχνοτήτων και περεμβολές λόγω αγωγής στις γραμμές συνεχούς.) - έρευνες που στοχεύουν στην διαμόρφωση των απαιτήσεων ασφαλείας. Οι κοινές δοκιμές ασφαλείας έναντι σε πλήγμα κεραυνού είναι βασισμένες σε ξεπερασμένα δεδομενα και δεν απεικονίζουν την πραγματική καταπόνηση. Για να υπερκεραστει αυτή η κατάσταση που διαπιστωθηκε σχετικά με την έμμεση επίδραση πλήγματος κεραυνού σε φ/β σύστημα, πραγματοποιήθηκε έρευνα σε έναν πειραματικό σταθμό που εγκαταστάθηκε σε θέση με υψηλό ποσοστό πληγμάτων από κεραυνό (Ng) (βουνό "Gaisberg", Αυστρία). Ένα σημαντικό αποτέλεσμα από τις μετρήσεις είναι ότι η κλήση του μετώπου του ρεύματος κεραυνού είναι κατά μέσον όρο 4 φορές υψηλότερη από τον τυποποιημένο παλμό ρεύματος 1.2/50 μs. Ένα σύστημα ανάλυσης αυτόνομων φ/β συστημάτων που χρησιμοποιείται στη νήσο Fuerteventura και εκτελέστηκε από την EnEtica, την arsenal research και την ISET έχει παρουσιάσει ποικιλία προβλημάτων όσον αφορά τα φ/β συστήματα. Μεταξύ αυτών, είναι προβλήματα με υπερρεύματα και βραχυκυκλώματα, ραδιο εκπομπή, αρμονικές, κλιματολογική επιρροή (κάλυψη από άμμο, διάβρωση), και άλλα. Τα αποτελέσματα από αυτές τις έρευνες χρησιμοποιήθηκαν για να υπογραμμίσουν την ανάγκη για νέες δοκιμές σε μερικά ηλεκτρονικά τμήματα των φ/β συστημάτων . ΟΙ μετρήσεις για το δίκτυο χαμηλής τάσης εκτελέσθηκαν από την EAM. Πρώτα, δίνεται μια επισκόπηση για τα χαρακτηριστικά του δικτύου χαμηλής τάσης από την άποψη των διακυμάνσεων της τάσης, της ανάλυσης αρμονικών, της σύνθετης αντίστασης, και άλλων παραμέτρων. Αφετέρου ερευνήθηκε η ανατροφοδότηση των Φ/Β συστημάτων στο δίκτυο χαμηλής τάσης . Η κύρια προσοχή της έρευνας της ISET εστιάστηκε στις έρευνες σχετικά με τη παρεμβολή των φ/β συστημάτων στις ραδιοφωνικές συχνότητες. Ένα αποτέλεσμα αυτών των ερευνών είναι χαρακτηριστικά, η σύνθετη αντίσταση και ο συντελεστής κεραίας των φ/β συστημάτων. Με βάση αυτήν την έρευνα προτείνεται μια εργαστηριακή εγκατάσταση με προσομοιωτή δικτύου με συνθετη αντίσταση γραμμής συνεχούς ρεύματος . Η έρευνα για άλλες απαιτήσεις, σχετικά με τους αντιστροφείς όσον αφορά τις παρεμβολές σε γραμμές εναλασσόμενου ρεύματος και τις αρμονικές, έχουν οδηγήσει σε πολλές νέες βελτιώσεις και προτάσεις σχετικά με την οργάνωση των δοκιμών και τα εφαρμόσιμα όρια. Οι έρευνες συνοδεύτηκαν από μια σειρά δοκιμών που διενεργήθηκαν σε διάφορους αντιστροφείς, για σύνδεση με δίκτυο, αντιστροφείς για αυτόνομα συστήματα και ρυθμιστές φόρτισης μπαταριών. Μεταξύ των άλλων θα μπορούσε να αποδειχθεί ότι ένας σημαντικός αριθμός αντιστροφέων διαθέσιμος σήμερα στην αγορά παράγει σήματα σε ραδιοσυχνότητες που ξεπερνούν τα όρια αντοχής των οικιακών συσκευών. Ένα είδος παρέμβασης είναι σήματα που εκπέμπονται στις γραμμές συνεχούς ρευματος από τους αντιστροφείς, και μπορούν να οδηγήσουν στη δημιουργεία σημαντικών ηλεκτρομαγνητικών πεδίων. Η εργασία που πραγματοποιήθηκε από την arsenal research επικεντρώθηκε γύρω από την επεξεργασία των νέων απαιτήσεων ασφάλειας για τα Φ/Β συστήματα. Ερευνήθηκαν επίσης όλες οι πιθανές διαταραχές που μπορούν να προκληθούν: υπερτάσεις λόγω βραχυκυκλωμάτων και διακοπτικών ενεργειών, υψηλές αρμονικές στο κύκλωμα εξόδου του αντιστροφέα, εργαστηριακές μετρήσεις των διαταραχών λόγω επαγωγής, κτλ. Διάφοροι μέθοδοι και μετρήσεις αναπτύχθηκαν για να αποφευχθούν αυτές οι διαταραχές ή για να επιτευχθεί το απαραίτητο επίπεδο ασφάλειας. Με βάση τις έρευνες έχουν αναπτυχθεί πλέον νέοι μέθοδοι δοκιμών και νέα κυκλώματα δοκιμών και επιπλέον προτείνονται νέες οδηγίες ασφάλειας.Αυτή η εργασία ολοκληρώθηκε με πρόσθετες δοκιμές που εκτελέσθηκαν σε αναστροφείς για παράλληλη λειτουργία δικτύου και ρυθμιστές φόρτισης μπαταριών. Αποτελέσματα ορισμένων δοκιμών είναι: a) Οι υψηλές διαταραχές στις συχνότητες των γραμμών εναλλασσόμενου ρεύματος σε φάσμα συχνότητας 10kHz - 150kHz. b) Πολλοί αντιστροφείς είναι πάρα πολύ ευαίσθητοι έναντι των σημάτων ελέγχου (200Hz - 3kHz). c) Το επαγωγικό μέρος του δικτύου μπορεί να οδηγήσει σε υψηλές αρμονικές στο κύκλωμα εξόδου του αντιστροφέα. d) ρεύματα μπορούν να οδηγήσουν σε μια σημαντική μείωση της τάσης παραγωγής των αντιστροφέων κάτι που αποτελεί κίνδυνο για συνδεδεμένους καταναλωτές. / In this project electromagnetic compatibility (EMC) and safety aspects of PV systems have been investigated in detail. The conclusions from these researches will contribute in the improvement and the creation of models with regard to the EMC and the safety of systems. The main topics covered by the project are: -inquiries concerning the electromagnetic environment (e.g. impact of lightning, measurements in low-voltage network and overvoltages manipulation.) -researches concerning emissions (scrambled area radio frequencies and conducted interference on mains and DC lines). -researches aimed at the formulation of safety requirements. The common safety tests versus lightening surge are based on outdated data and do not reflect the actual force. To overcome this situation in concern with the indirect lightening surge in PV systems, a research was performed, at an experimental station installed at a location with a high natural lightening rate (Ng). An important result of the measurement is that the call of the front of the lightning surge is on average 4 times higher than the standard pulse power 1.2/50 μs. A system of analysis autonomous PV systems used on the island of Fuerteventura and carried out by the EnEtica, arsenal research and ISET has presented a variety of problems with regard to the PV systems. Among them are problems with overcurrents and short circuits, radio broadcast, Harmonics, climatic influence (covered by sand and erosion), and more. The results of these surveys used to emphasize the need for new tests in some electronic parts of PV systems. Measurements for the low-voltage network have been carried out by the EAM. At first, was given an overview of the characteristics of the low-voltage network in terms of fluctuations of the voltage, harmonic analysis, impedance, and other parameters. The main attention of the investigation of ISET focused on the interference of PV systems in radio frequencies. A result of these investigations is the impedance and the antenna factor of PV systems. In addition with this survey was proposed a lab network Simulator installation with advanced DC line impedance. The investigation of other requirements concerning inverters with regard to interferences in AC lines and harmonics, have led to many new improvements and proposals concerning the Organization of the tests and the applicable limits. The investigations have been accompanied by a series of tests carried out on various inverters, for connection to a network, inverters for stand-alone systems and regulators battery chargers. From these investigations was proved that a significant number of inverters which are available on the market today produces on radio frequencies which go beyond resistance of household appliances. A type of interference is signals emitted by inverters on the lines and can lead to important electromagnetic fields. The work performed at arsenal research was concentrated around the elaboration of new immunity and safety requirements for PV systems. Analysis was made for all the possible disturbances likely to cause: surge due to short circuits and switching actions, high harmonics in the circuit of the inverter, laboratory measurements of the disturbances due to induction, etc. Various methods and measurements were developed to avoid these disorders, or in order to achieve the necessary level of security. Using the results of the investigations have been developed new methods of testing and new testing circuits and in addition are proposed new directives for security. This task was completed with additional tests carried out in inverters for parallel network operation and regulators battery chargers. Results of certain tests are: a) High disturbances in the frequencies of AC lines in range of frequency 10 kHz-150kHz b) Many inverters are very sensitive to the trade signals (200Hz-3 kHz) c) The inductive part of the net may lead to high harmonics in the output of the inverter circuit. d) impact currents can lead to a significant reduction in the production of the inverter’s voltage which constitutes a risk for linked consumers. Pilot PV systems have been created by the cooperation of ISET, and EnEtica. These systems are used to demonstrate and to investigate the EMC of PV systems (System ISET), the safety requirements (arsenal system) and problems that are created specifically for distributed PV systems in different areas. (System EnEtica).

The master´s thesis describes the design of the remote control, which is used as accessories for motor circuit-breaker. The work is based on the concept of control realized in the bachelor´s thesis. Master’s thesis contains a literature review of management method stepper motors with integrated circuits. standards relating to the control and switching low voltage devices were rehearsed. It was compiled schema of an entire unit after designing optimal control section of a stepper motor with integrated circuits, which consists of four parts (power supply, power section for driving an coils of stepper motor, control section and section for driving external devices). Design and realization of PCB are based on compiled schema, PCB was mounted with components and final PCB was recovered. The last part of thesis is about verification a functionality with using measurement of a prototype parameters.

Orientador: Prof. Dr. Álvaro Batista Dietrich / Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Engenharia Elétrica, 2014. / Com a crescente utilização da eletrônica embarcada nos veículos atuais em produção, surgiu uma preocupação sobre os efeitos causados por campos eletromagnéticos em módulos e sistemas eletrônicos. Esses campos podem ser gerados por fontes intencionais, como por exemplo, uma emissora de rádio ou devido a uma fonte não intencional, isto é, um campo gerado pelo funcionamento de outro sistema eletrônico, pelo próprio módulo ou pelo cabeamento utilizado para a conexão elétrica desses dispositivos. Desta forma, o objetivo desse trabalho é avaliar a intensidade de um campo eletromagnético irradiado pelo próprio veículo em seu interior, na região onde geralmente é instalado o rádio/GPS ou sistema multimídia e verificar a possibilidade deste campo interferir no funcionamento do Bluetooth. Alguns ensaios foram conduzidos e os campos irradiados pelo veículo em determinadas situações de funcionamento foram medidos. Ademais, utilizando o software de simulação CST (Computer Simulation Technology), realizou-se uma proposta para a abordagem de modelamento computacional dessas medidas na região do painel de instrumentos do veículo. Os resultados obtidos nos ensaios mostraram que o sistema elétrico do veículo não produz campos ou ruídos eletromagnéticas que possam interferir no funcionamento do Bluetooth. Também verificou-se que o CST pode ser utilizado como uma importante ferramenta de modelagem computacional. Portanto, esse trabalho fornece requisitos para um refinamento dos processos de medição e simulação dos efeitos de EMC (Electromagnetic Compatibility) e constata que há alternativas para redução de recursos financeiros de forma direta e na agilidade de se obter diferentes cenários de simulação. / With the increasing use of electronics in current production vehicles, a concern about the effects caused by electromagnetic fields in modules and electronic systems emerged. These fields can be generated by intentional sources, such as a broadscast transmitter or due to an unintentional source, i.e., a field generated by the operating system, for itself or other electronic cabling used for the electrical connection of these devices. Thus, the aim of this study is to evaluate the intensity of an electromagnetic field radiated by the vehicle itself within, the region where the radio / GPS or multimedia system is usually installed and consequently the possibility of this field interfered with Bluetooth. Tests were conducted and the radiated fields in certain operating situations were measured. Moreover, using the simulation software CST (Computer Simulation Technology), there was a proposal for early computational modeling of such measures on the vehicle instrument panel area. The test obtained results showed that the vehicle's electrical system does not produce noise or electromagnetic fields that can interfere with existing Bluetooth operation. Furthermore, it was found that the CST could be used as an important tool of computer modeling. Therefore, this work provides requirements for a refinement of current procedures on the measurement and simulations. It points out directions for alternatives on the cost reduction related to these studies, as well as agility different simulation scenarios.

Made available in DSpace on 2014-06-11T19:22:34Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-01-27Bitstream added on 2014-06-13T20:49:15Z : No. of bitstreams: 1 sartin_acp_me_bauru.pdf: 2377399 bytes, checksum: d4b29001d0dcb0173350d8175fba63b3 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O presente trabalho possui como foco principal a apresentação de proposições técnicas para a avaliação da suscetibilidade eletromagnética de cabos metálicos isolados, blindados ou não, para atender aos sistemas de supervisão, proteção, comunicação e controle de subestações de alta tensão frente às interferências eletromagnéticas provocadas pelas descargas atmosféricas, manobras de chaveamento, campo magnético na frequência de 60Hz e do efeito corona. Para a realização destas proposições foram analisados e estudados diversos cabos usados em uma subestação de 440kV. A diretriz metodológica adotada nesta pesquisa incorporou simulações de modelo computacional, ensaios laboratoriais recomendados pelas normas e publicações técnicas correlatas com a finalidade de identificar os efeitos provocados pelas interferências eletromagnéticas nesses cabos. Os resultados obtidos conduziram a uma análise da interferência eletromagnética nos diversos cabos avaliados fornecendo, assim, um valor de imunidade de cada cabo estudado. Constatou-se que os cabos sem blindagem devem ser usados com reservas e podem ser instalados em sistemas poucos sujeitos a interferências eletromagnéticas ou promover uma blindagem adicional. Os cabos blindados, menos suscetível a interferências eletromagnéticas, podem ser instalados em pátios de subestações, entretanto devem-se tomar os devidos cuidados com o aterramento da blindagem. Desta forma, a pesquisa realizada contribuiu para o desenvolvimento de um procedimento técnico para o uso adequado de cabos em questão visando minimizar os efeitos provocados pelas interferências eletromagnéticas nos sistemas de supervisão, proteção, comunicação e controle presentes em subestações de alta tensão. / The main focus of this work is the presentation of technical propositions to assessing the electromagnetic susceptibility of isolated metallic cable, shielded or not, in order to comply with the supervision, protection, communication and control systems of high voltage substations in the presence of electromagnetic interferences caused by lightning discharge, switching maneuver, electromagnetic field at 60Hz and corona effect. Several cables used in 440 kV substation were analyzed and studied for accomplishing these propositions. The methodological guideline adopted in this research has included simulations of computational models, laboratorial tests recommended by standards and technical publications correlated in order to identifying the effects provoked by electromagnetic interferences to these cables. The obtained results led to an analysis of the electromagnetic interference in the several cables assessed, thus providing a value of immunity for each cable studied. It was verified that cable without shielding must be employed with restrictions and can be installed in systems which are little subject to electromagnetic interference or to promote an additional shielding. The shielding cables less susceptible to the electromagnetic interference can be installed in substation courtyard; however, it is important to pay special attention to the grounding of the shielding. Thus, this research contributed to the development of a technical proceeding for employing the mentioned cables suitably, aiming at minimizing the effects provoked by the electromagnetic interferences in the supervision, protection, communication and control systems which are present at the high voltage substations.

Orientador: José Alfredo Covolan Ulson / Banca: Paulo Roberto de Aguiar / Banca: José Carlos de Melo Vieira Junior / Resumo: O presente trabalho possui como foco principal a apresentação de proposições técnicas para a avaliação da suscetibilidade eletromagnética de cabos metálicos isolados, blindados ou não, para atender aos sistemas de supervisão, proteção, comunicação e controle de subestações de alta tensão frente às interferências eletromagnéticas provocadas pelas descargas atmosféricas, manobras de chaveamento, campo magnético na frequência de 60Hz e do efeito corona. Para a realização destas proposições foram analisados e estudados diversos cabos usados em uma subestação de 440kV. A diretriz metodológica adotada nesta pesquisa incorporou simulações de modelo computacional, ensaios laboratoriais recomendados pelas normas e publicações técnicas correlatas com a finalidade de identificar os efeitos provocados pelas interferências eletromagnéticas nesses cabos. Os resultados obtidos conduziram a uma análise da interferência eletromagnética nos diversos cabos avaliados fornecendo, assim, um valor de imunidade de cada cabo estudado. Constatou-se que os cabos sem blindagem devem ser usados com reservas e podem ser instalados em sistemas poucos sujeitos a interferências eletromagnéticas ou promover uma blindagem adicional. Os cabos blindados, menos suscetível a interferências eletromagnéticas, podem ser instalados em pátios de subestações, entretanto devem-se tomar os devidos cuidados com o aterramento da blindagem. Desta forma, a pesquisa realizada contribuiu para o desenvolvimento de um procedimento técnico para o uso adequado de cabos em questão visando minimizar os efeitos provocados pelas interferências eletromagnéticas nos sistemas de supervisão, proteção, comunicação e controle presentes em subestações de alta tensão. / Abstract: The main focus of this work is the presentation of technical propositions to assessing the electromagnetic susceptibility of isolated metallic cable, shielded or not, in order to comply with the supervision, protection, communication and control systems of high voltage substations in the presence of electromagnetic interferences caused by lightning discharge, switching maneuver, electromagnetic field at 60Hz and corona effect. Several cables used in 440 kV substation were analyzed and studied for accomplishing these propositions. The methodological guideline adopted in this research has included simulations of computational models, laboratorial tests recommended by standards and technical publications correlated in order to identifying the effects provoked by electromagnetic interferences to these cables. The obtained results led to an analysis of the electromagnetic interference in the several cables assessed, thus providing a value of immunity for each cable studied. It was verified that cable without shielding must be employed with restrictions and can be installed in systems which are little subject to electromagnetic interference or to promote an additional shielding. The shielding cables less susceptible to the electromagnetic interference can be installed in substation courtyard; however, it is important to pay special attention to the grounding of the shielding. Thus, this research contributed to the development of a technical proceeding for employing the mentioned cables suitably, aiming at minimizing the effects provoked by the electromagnetic interferences in the supervision, protection, communication and control systems which are present at the high voltage substations. / Mestre

La compatibilité électromagnétique (CEM) est l’une des contraintes majeures de la conception des structures de l’électronique de puissance. Pour le cas des convertisseurs statiques, la commutation des semi-conducteurs et leurs interactions avec les éléments parasites liés à l’environnement sont la source principale des perturbations conduites. Cette interaction ne cesse d’augmenter notamment avec l’industrialisation des nouvelles générations de semi-conducteurs à grand gap qui deviennent de plus en plus impressionnantes grâces à leurs faibles pertes en commutation et à leur rapidité croissante. Malheureusement, l’étude de ces perturbations est souvent considérée comme le dernier obstacle à la commercialisation et elle n’est pas prise comme contrainte de conception. L’estimation a priori de ces perturbations par la simulation peut permettre un gain considérable tant sur le plan économique que sur le temps de traitement. Dans ce mémoire, nous mettons l’accent sur les modèles de composants semi-conducteurs et leurs effets sur les perturbations conduites dans les convertisseurs statiques. Cette étude mettra aussi en évidence les problèmes liés aux simulations temporelles ou fréquentielles et l’utilité de chacune. Ensuite, nous proposons des modèles pour le MOSFET et pour la diode Shottky en technologie carbure de silicium et nous analysons l’influence de leurs paramètres sur les perturbations conduites dans un circuit de hacheur. Nous exposons aussi une approche permettant d’obtenir des temps de simulation plus raisonnables en introduisant le principe de contrôle des signaux parasites et des cycles de fonctionnement. Finalement, nous introduisons une nouvelle méthode de description des commutations par des sources équivalentes. Nous montrons qu’il est possible à partir de l’étude de la loi de commande de proposer une méthode de synthèse d’une cellule de commutation permettant de reconstruire ses grandeurs électriques de sortie. / Electromagnetic compatibility (EMC) is one of the major constraints involved in the design of power electronics structures. In the case of static power converters, the switching of semiconductors and their interactions with the parasitic elements related to the environment are the main source of conducted disturbances. This interaction is increasing especially with the industrialization of new generations of wide band gap semiconductors that become increasingly impressive thanks to their low switching losses and their rapidity. Unfortunately, the study of the disturbances is often considered as the last obstacle to the marketing and it is not taken as a design constraint. An early estimation of these disturbances by simulation can provide a reduction in processing time and a considerable economic gain. In this manuscript, we focus on semiconductors models and their effects on conducted interference in static converters. This study will also reveal problems related to time or frequency simulations and usefulness of each one. Then, we propose models for silicon-carbide MOSFET and Schottky diode and we analyze the influence of their parameters on the conducted disturbances in a chopper circuit. We also expose an approach to obtain more reasonable simulation time by controlling parasitic signals and operating cycles. Finally, we introduce a new method to describe switching’s by using equivalent sources. We show that by studying the command law, it is possible to propose a synthesizing method of a switching cell able to rebuild its electrical outputs.

Les systèmes de communication à bord de certains navires ou véhicules terrestres peuvent être très nombreux. Il en résulte des architectures de systèmes rayonnants particulièrement élaborées. La compacité de ces systèmes et leur compatibilité radioélectrique représentent des enjeux importants. Dans le cadre du projet SAMCOM, les partenaires de projet s'attachent à exploiter l'avantage des parois porteuses en composite en termes d’intégration des antennes en paroi et de découplage électromagnétique entre éléments rayonnants. Cette thèse porte essentiellement sur deux volets. La première partie porte sur la question d'intégration des antennes en paroi. Il s'agit pour l'essentiel de s'assurer que les caractéristiques de fonctionnement intrinsèque de l'antenne associée à la paroi puissent être maintenues lorsque celle-ci est fixée sur une paroi composite. Le second volet de cette thèse concerne le découplage d'antennes associées à une même paroi composite. Il s'agit de rechercher les moyens qui permettraient d'augmenter les performances de découplage entre antennes et par conséquent de limiter l’espacement entre elles. Les solutions d'intégration examinées dans la thèse concernent la mise en oeuvre de matériaux de type ferrite, d’absorbants ou encore l’utilisation de surfaces haute impédance (SHI). Dans le premier cas, nous nous sommes attachés à optimiser la localisation de ferrites de sorte à minimiser leur volume pour des questions de coût et de poids. Les surface artificielles de type SHI ont été examinées et une procédure de dimensionnement adaptée à la paroi composite de la surface SHI a été élaborée. Nous abordons ensuite les solutions de découplage d'antennes hébergées sur une même paroi composite. La première solution de découplage étudiée concerne l'utilisation d'absorbants électromagnétiques. Nous montrons qu'il s'agit d'une solution très adaptée si nous disposons d’un absorbant dont le contraste d’impédance avec l’onde incidente est faible sur toute la bande de fréquence sous peine de subir les effets de bord. La deuxième solution envisagée concerne les surfaces à bande interdite électromagnétique (BIE). Nous montrons en particulier qu’une surface de type BIE peut présenter d’excellentes performances de découplage si toutefois cette surface est adaptée suivant sa hauteur. Une partie importante de ce travail a été consacrée à l'évaluation de solutions de découplages originales basées sur l'emploi d'une simple tige conductrice cylindrique puis d'un ensemble de tiges cylindriques. Nous montrons en particulier qu'une simple tige peut apporter un découplage significatif en bande étroite tandis qu'une forêt de tige contribue à assurer un découplage sur une plus large bande de fréquence. / Communication systems on board modern military ships or land vehicles can be numerous. This results in particularly developed radiating systems. The compacity of these systems and radio compatibility are major challenges. Under the Samcom project, the project partners are working to exploit the advantage of composite structural walls in terms of integration of antennas wall and electromagnetic decoupling between radiating elements. This thesis focuses on two parts. The first part consists in the study of integration of antennas on wall made up of composite materials. This is essentially to ensure that the operating characteristics of the antenna associated with the supporting structure can be maintained when it is fixed to a composite wall. The second part of this thesis is related to antenna decoupling mounted on the same ground plane. The aim is to find techniques to reduce antenna coupling and thus the separation between them. Integration solutions examined in the thesis concern the implementation of ferrite materials, absorbent and high impedance surfaces. In the first case, we attempted to optimize the location of ferrites so as to minimize their volume, thus saving cost and weight. Artificial higher impedance surface (HIS) have been examined and a design procedure adapted to the wall of the composite of the SHI surface has been developed. We then discuss on the solutions of antenna decoupling on a composite wall. The first decoupling solution investigated concerns the use of electromagnetic absorbers. We show that this is a very suitable solution if we have an absorbent whose impedance contrasts with that of the incidence wave is weak on full band frequency under penalty of sides effects. The second option concerns the surfaces electromagnetic bandgap. To ensure adequate decoupling performance, BIE surface must be adjusted in height. An important part of this work is dedicated to the assessment of some innovative decoupling solutions based on the use of a single cylindrical conducting rod. Indeed, we show on the one hand a single rod can lead to significant decoupling in a narrow band while on the other hand, a set of cylindrical rods contribute to ensure a rather broadband decoupling.

L'augmentation du nombre de fonctions électriques disponibles dans les systèmes embarqués amène de nouvelles contraintes d'encombrement et de masse de leurs alimentations. Pour adresser ces problèmes, la miniaturisation et l'intégration des convertisseurs statiques sont donc des thématiques importantes de recherche qui aboutissent à de nombreuses évolutions technologiques et structurelles dont l'apparition de convertisseurs statiques à fréquence de fonctionnement élevée permettant la réduction des éléments passifs du convertisseurs.Ces avancées s'accompagnent cependant d'une augmentation des niveaux de perturbations électromagnétiques générés par le système. Afin de les diminuer, l'insertion de filtres CEM dans le système est nécessaire. Leurs performances sont fortement liées au contrôle de leurs éléments parasites. Les modèles développés jusqu'à présent concernent pour la plupart les effets conduits et l'évaluation de l'impact des phénomènes rayonnés est souvent ignoré ou au mieux basé sur des modèles simplistes. Un des objectifs de cette thèse est donc d'apporter un degré de complexification plus élevé des modèles de rayonnement des composants magnétiques utilisés dans les filtres CEM, tant par une approche par modélisation numérique que par la mise en oeuvre d'un modèle analytique.Dans un premier temps, une étude poussée du rayonnement magnétique de composants simples, les inductances toriques de mode différentiel, a été réalisée. Cette étude a débouché sur la mise en évidence des paramètres critiques déterminant la topologie du champ magnétique rayonné dans l'environnement proche du composant. Le résultat majeur de cette étude est l'importance de la répartition du bobinage autour du circuit magnétique sur le champ magnétique rayonné. De nouveaux modèles ont été proposés pour permettre la prédiction des champs proches rayonnés pour une gamme de fréquence inférieure à la résonance propre du composant.Par la suite, un modèle analytique fin du rayonnement magnétique des inductances de mode commun a été proposé. Ce modèle permet de déterminer \emph{a priori} le rayonnement magnétique proche du composant. Les études menées par la suite ont permis de relier les effets observés en rayonné au phénomènes conduits qui apparaissent dans ces composants notamment pour expliquer certains effets de transfert de mode (commun/différentiel).Dans une dernière partie, une étude de ces composants en susceptibilité électromagnétique (EM) a été menée. Elle a permis de rendre compte de l'influence d'une onde incidente de champ magnétique sur les composants étudiés et de valider les modèles proposés via une approche basée sur la réciprocité EM: la direction privilégiée de rayonnement est aussi celle de couplage facile pour un champ magnétique externe. / The number of electronic devices in embedded systems is constantly increasing and their contribution to volume and weight is a major concern. In order to solve these issues, a large research effort is devoted to volume reduction and power converters' integration. This lead to constant technological evolution including the appearance of high frequency power electronic converters allowing the reduction of the volume of passive components.However, due to the increase of operating frequencies and the minimization of inter-components distances, the electromagnetic radiations generated by these systems become more important. In order to decrease this interference, EMI filters are often necessary. Their performances are often related to the value of parasitic elements in the filter which must therefore be controlled. Nonetheless most of the existing models focus on conducted electromagnetic interference (EMI) and the impact of radiated phenomena is often ignored or greatly simplified. This work will therefore focus on developing highly accurate radiation models for magnetic components commonly used in EMI filters using both numeric and analytic tools.First, the magnetic fields radiated by differential mode (MD) toroidal coils, which belong to the basic magnetic components, will be thoroughly studied. This study highlighted the critical parameters determining the near-field topology. The main result is the discovery of the impact of the winding's layout around the magnetic core on the radiated magnetic field. New models have been developed in order to predict the radiated near field.Then, an accurate analytic model of the the magnetic radiation of common-mode (CM) chokes has been developed. It allows the prediction of the magnetic near-field. The application of the model lead to the correlation between radiated phenomena and conducted effects existing in these components. The importance of the winding on CM to DM mode coupling has therefore been highlighted.Finally, the electromagnetic (EM) susceptibility of these components has been studied. This work describes the influence of an external magnetic field on the components and validates the radiation models developed using the principle of EM reciprocity. It has been shown that the easy directions are the same for both the radiated and the coupled phenomena.

This Master’s project deals with general aspects and possible solution of effective shielded cover and cell/chamber shielding measurement for needs of electromagnetic compatibility EMC on the basis of available norms and standards. Electromagnetic shielding is one of the most anticlutter means of EMC. Its main task is reduction of disturbing emission at the side of sources of disturbing signals as well as electromagnetic resistance increase at the side of disturbing signal receivers. Shielding is considered to be an important structural means to reduce electromagnetic field referring to a defined space part. Technical means for achieving the given goals are called shielded covers or shielded cells/chambers. Shielding is one of highly effective methods related to electromagnetic protection, for instance against power/output disturbance. To express the shielding quality so called shielding effectiveness SE is used. It represents logarithmic rate of shielding coefficient that is defined by the intensity ratios of electric and magnetic fields in a certain point of the shielded space to electric or magnetic field intensity incident/impinging on the shielded screen or wall.