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11	Etude et intégration de convertisseurs multicellulaires parallèles entrelacés et magnétiquement couplés Bouhalli, Nadia 11 December 2009 (has links) (PDF) L'apparition de convertisseurs multicellulaires parallèles entrelacés et magnétiquement couplés a conduit ces dernières années à améliorer les performances des convertisseurs (densité de puissance, efficacité, dynamique,...). Il existe plusieurs topologies d'entrelacement qui utilisent des Transformateurs Interphases. L'objectif principal de cette étude est de trouver parmi ces topologies celles qui sont les mieux adaptées à un contexte d'intégration d'électronique de puissance pour minimiser la taille et réduire les pertes. Une première étape de modélisation a permis d'effectuer une étude comparative de quelques topologies. Un procédé de permutation des phases d'alimentation a été présenté afin de réduire les ondulations du courant de phases et les pertes ohmiques. Les résultats obtenus valident qualitativement l'avantage de la solution retenue par rapport à la solution standard. Enfin, la réalisation pratique d'un prototype de convertisseur modulaire utilisant des Transformateurs Inter-phases est abordé. Il s'agit d'un régulateur chargé d'alimenter les microprocesseurs (1,2V/100A) (Voltage Regulator Module (VRM)) à 5 modules. Les résultats expérimentaux montrent l'avantage de l'utilisation des Transformateurs Inter-phases par rapport à la solution classique. Transformateur Inter-phases Coupleur magnétique Modélisation harmonique Convertisseur modulaire Voltage Regulator Module (VRM)
12	Information för beslutsunderlag i trafiksituationer inom sjöfarten - hur hanterar vi den? Arnold-Larsen, Kimmo January 2012 (has links) I detta examensarbete har jag undersökt förmågan hos nautiker att ta fram och tillgodogöra sig information från radar och ARPA för sitt beslutsunderlag i trafiksituationer. Syftet var att få förståelse i om fartygsbefäl haft svårigheter att få fram denna mycket relevanta information. Detta gjordes med hjälp av förstudier i form av intervjuer med erfarna fartygsbefäl. Dessa intervjuer gav kriterier som möjliggjorde analyseringen av 13 olycksfallsrapporter, vilket utgjorde litteraturstudien. Dessa rapporter var författade av engelska Department of Transport, Marine Investigation Branch(MAIB), Statenshaverikommission(SHK) och Sjöfartsverkets rapportserie(SjöfR). Dessutom användes både sjö- och luftfartsrelaterade artiklar för framtagning av fakta. Slutsatserna visade att man i hälften av fallen använt sig av väldigt låg nivå på funktionalitet för sitt beslutsunderlag, men att även i de fall man använt mer avancerad funktionalitet fann man brister i tolkning av informationen för att i tid ta beslut för att undvika olyckor. / This is a study about the Navigating Mariners ability to locate and use information from the Radar and ARPA, before taking important decisions in Trafic Situations. The purpose was to acquire an understanding if there are some difficulties in receiving this important information. This purpose was accomplished by a pre-investigation using two interviews with experienced deck officers. This pre-study produced criterias, that made it possible to compare 13 Accident Reports. These reports were used as a litterature for the investigation. The Department of Transport, Marine Investigation Branch(MAIB), The Swedish Accident Investigation Board(SHK) and The Swedish Maritime Safety Inspectorate(SjöfR) had produced these reports. In addition to these reports, the author used both maritime- and aeronautical based articles in order to find more facts about the issues around the investigation. The findings showed that in half of the investigated accidents the mariners involved had used a low level of functionality before making the final decisions. It was also shown, that the ones that had used a very high level of functionality, before the accident, misinterpreted the information and failed to take the right decision in ample time before the accident. cockpit design standards Collision Collision Regulations Collision Risks Risk Management Trial Manoeuvre Trails EBL VRM Parallellindex PI
13	Proposta de um compensador sériie de tensão de elevada dinâmica para a correção da tensão instantânea da carga diante de afundamentos ou elevações da tensão da rede elétrica Freitas, Pedro Augusto Ramos de 18 July 2014 (has links) This paper proposes two new topological arrangements consisting in connecting the AC power supply in series with two DC converters, one operating during the positive half-cycle and the other during the negative half cycle. It is noteworthy that these DC converters in series in a case are Buck EIE converters and on the other a buck. The results obtained with both arrangements are analyzed and compared. The control strategy is developed with the goal of imposing an AC voltage output within the limits imposed by the rules in order to mitigate the problems associated with Sags and Swells from the AC power supply . The principles of operation as well as the experimental and simulation results obtained in both steady and transient state are presented and validated for a 1kVA experimental prototype. Finally, some works still on progress related to this dissertation are presented, like the multilevel compensation and the three phase compensation. / Este trabalho propõe dois novos arranjos topológicos que consistem em se conectar a alimentação CA em série com dois conversores CC, um para operar durante o semiciclo positivo e o outro durante o semiciclo negativo. Vale ressaltar que estes conversores CC em série, em um caso são conversores Buck EIE e no outro um conversor Buck. Os resultados obtidos com ambos os arranjos são analisados e comparados. A estratégia de controle é desenvolvida com o intuito de impor uma tensão de saída CA dentro dos limites impostos pelas normas de forma a mitigar os problemas associados com Sags e Swells da rede de alimentação CA. Os princípios de operação, os resultados experimentais e de simulação obtidos, tanto em regime permanente quanto em condições transitórias de operação, são apresentados e validados para um protótipo experimental de 1kVA. Por fim apresentam-se os trabalhos relacionados a esta dissertação que ainda estão em desenvolvimento, que são a compensação em multinível e a compensação trifásica. / Mestre em Ciências Conversor CA/CA Modulo regulador de tensão(VRM) Compensador série de tensão Conversor CC-CC Buck Conversores de corrente elétrica AC/AC converter Voltage regulater mode Series compensator DC-DC converter CNPQ::ENGENHARIAS::ENGENHARIA ELETRICA
14	Key Characteristics as a Practice toAchieve Robust Design : A case study in the aerospace industry / Användande av nyckelegenskaper för att uppnå robust konstruktion : En fallstudie inom flygindustrin Berglund, Jacob, Ericsson, Martin January 2014 (has links) Continuous technological development and increasing efficiency demands are driving products toward becoming more and more complex. For the aerospace industry - where the requirements for performance, safety and low environmental impact already are substantial - this means that more extensive quality assurance measures must be taken to ensure the fulfillment of the requirements of each individual component.However, to avoid that the work with quality improvement become too extensive and increase the product cost to unbearable levels it is necessary to have methods to prioritize and focus improvement efforts on the product features that matters most for fulfilling customer requirements. Therefore, the concept of Key Characteristics is used today, both in the aerospace and other industries; a term for those characteristics that have a significant impact on requirement compliance and whose outcomes at the same time are expected to vary considerably in manufacturing.The concept itself is similar among those who use it but the purpose of and methodology for identifying and managing Key Characteristics vary, even within the same industry. This thesis is therefore aimed to create a view of which factors that characterize an effective and efficient way for companies in the aerospace industry to work with Key Characteristics. The thesis involves a case study to create a framework for how companies within this industry work with Key Characteristics, a literature review to see which approaches are advocated by previous research and two benchmark studies to see examples of how Key Characteristics are used and handled in practice in industry.The results show that the work of Key Characteristics should meet three main criteria in order to be effective and efficient: • it must be clearly focused on the characteristics that have critical impact on customer requirements and at the same time considerable variation in production, • it should be initiated early in the product development process and then performed iteratively during the process of continuously reducing variation problems in manufacturing, and • it should identify Key Characteristics using both qualitative and quantitative tools to best capture all different kinds of requirements on the product.Finally a practical example is given of how the work with Key Characteristics should look like at GKN Sweden AB, the case study company in the aerospace industry, to effectively minimize the costs associated with production variation, and yet satisfy all customer requirements. / <p>Validerat; 20140811 (global_studentproject_submitter)</p> Technology Teknik Robust Design Design for robustness Key characteristics Key Characteristic Aerospace GKN Aircraft Variation AS9103 Variation management Risk Volvo Saab Variation risk management Flight safety Safety Flow-down Thornton Critical item Critical Item Characteristics Proactive VRM CI KC Risk mitigation Flowdown Product development Development Product characteristics Product defects Defect Deviation Variation cost Quality Critical effect PDP

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