This diploma thesis deals with the analysis and description of high power laboratory CVVOZE. In the text we can find a description of the individual elements high power laboratory stating their parameters and their analysis from the perspective of impedance. The practical concern of this work is the creation of program for calculating the adjustment burdens and creating utilities helpful for operation and interpretation of laboratory function laity and technical employees.

The work is focusing on dynamic effects of short-circuit currents, more precisely dynamic effects of short-circuit currents on switchgear cabinet (terminal box). The work was designated to a concrete construction type of two switchgear cabinets located on rotating machines via company Siemens Electric Machines Drásov s.r.o.. The switchgear cabinets are designed for non-explosive environment where the air is used as an insulating medium. The task was to determine how the device will behave during the three-phase short-circuit and three-phase short-circuit with earth/ground connection. The following programs were used for the calculations and simulations: Ansoft Maxwell 16.0, Ansoft Maxwell 2015 and ANSYS Workbench 16.0. By using these programs the effects of forces which acts on current paths in cabinet caused by the passage of short-circuit current were simulated, statically and also dynamically. Further the effects of pressure acting on cabinet frame during the arc short-circuit have been statically and dynamically simulated. All the results are summarized in the conclusion. Conclusion also contains the final evaluation of the functionality of both switchgear cabinets.

<p>Repeatable methods for introducing minor defects in commercial Li-ion pouch cells were developed and different studies were conducted to compare the different signatures that would provide information regarding the factors that are most critical to detect the onset of internal short circuit for each defect test. The cells were subjected to overcharge, over-discharge, nail indentation and heating defect tests. After defect introduction, three different studies – cycling, thermal runaway, and self-discharge were performed on the cells. The overcharge defect case showed signatures in all three studies with the major cause of these signatures being lithium dendrite formation that led to reduction in capacity. The overcharge case was also unique in that it showed recovery in capacity due to lithium stripping process and had the highest temperature recorded which proves that it had the most dangerous defect case. The over-discharge case showed signs of possible copper deposition on the anode side which was evident by the presence of lithium plating in patches which could have been due the copper deposition locations becoming active sites for lithium plating. The nail indentation defect case showed signatures in the thermal runaway study by the shortest time it took to go into thermal runaway and in the self-discharge study which was shown by the inability of cells to stay at a stable voltage even at the most stable SOC. The heating defect test showed potential in that it was able to melt the separator near the pouch and that it had a lower temperature for onset of exotherm, but improvements need to be made to get more conclusive results for this defect case.</p>

Wortmannin is a potent inhibitor of phosphatidylinositol 3-kinase (PI3K) and membrane trafficking in many cells. To test the hypothesis that cystic fibrosis transmembrane conductance regulator (CFTR) traffics into and out of the plasma membrane during cAMP-stimulated epithelial Cl- secretion, we have studied the effects of wortmannin on forskolin-stimulated Cl- secretion by the human colonic cell line T84. At the PI3K inhibitory concentration of 100 nM, wortmannin did not affect significantly forskolin-stimulated Cl- secretion measured as short-circuit current (I(SC)). However, 500 nM wortmannin significantly inhibited forskolin-stimulated I(SC). cAMP activation of apical membrane CFTR Cl- channels in α-toxin-permeabilized monolayers was not reduced by 500 nM wortmannin, suggesting that inhibition of other transporters accounts for the observed reduction in T84 Cl- secretion. Forskolin inhibits apical endocytosis of horseradish peroxidase (HRP), but wortmannin did not alter forskolin inhibition of apical HRP endocytosis. In the absence of forskolin, wortmannin stimulated HRP endocytosis significantly. We conclude that, in T84 cells, apical fluid phase endocytosis is not dependent on PI3K activity and that CFTR does not recycle through a PI3K-dependent and wortmannin-sensitive membrane compartment.

Mes travaux de thèse dans les laboratoires SATIE de ENS de Cachan et Ampère de l’INSA de Lyon se sont déroulés dans le cadre du projet Gestion OptiMisée de l'Energie (GENOME) pour étudier le potentiel de certains composants de puissance (JFET, MOSFET et BJT) en carbure de silicium (SiC) dans des convertisseurs électroniques de puissance dédiés à des applications aéronautiques suite au développement de l'avion plus électrique. La première partie de mes travaux étudie la robustesse de MOSFET et BJT en SiC soumis à des régimes de court circuit. Pour les MSOFET SiC, en soumettant ces transistors à la répétition de plusieurs courts-circuits, nous observons une évolution du courant de fuite de grille qui semble être un bon indicateur de vieillissement. Nous définissons une énergie critique répétitive pour évaluer la robustesse à la répétition de plusieurs courts-circuits. Aucun effet significatif de la température ambiante n’a pu être mis en évidence sur la robustesse des MOSFET et BJT SiC sous contraintes de court-circuit. Pour les MOSFET, nous avons également constaté une élévation significative du courant de fuite de grille en augmentant de 600V à 750V la tension, ce qui se traduit également par une défaillance plus rapide. Après ouverture des boîtiers des MOSFET Rohm ayant présenté un court-circuit entre grille et source après défaillance, on remarque une fusion de la métallisation de source qui vient effectivement court-circuiter grille et source. Dans ce mode de défaillance particulier, le court-circuit entre grille et source auto-protège la puce en lui permettant de s’ouvrir.La deuxième partie de ce mémoire est consacrée à l’étude de JFET, MSOFET et BJT SiC en régime d’avalanche. Les JFET de SemiSouth et les BJT de Fairchild présentent une bonne robustesse à l’avalanche. Mais le test d'avalanche révèle la fragilité du MOSFET Rohm puisqu’il entre en défaillance avant d’entrer en régime d’avalanche. La défaillance du MOSFET Rohm et sa faible robustesse en régime d’avalanche sont liées à l’activation du transistor bipolaire parasite. Le courant d'avalanche n’est qu’une très faible partie du courant dans l’inductance et circule du drain/collecteur à la grille/base pour maintenir le transistor en régime linéaire. Une résistance de grille de forte valeur diminue efficacement le courant d'avalanche à travers la jonction drain-grille pour le JFET.La troisième partie concerne l’étude de la commutation de BJT SiC à très haute fréquence de découpage. Nous avons dans un premier temps cherché à valider des mesures de pertes par commutation. Après avoir vérifié l'exactitude de la méthode électrique par rapport à une méthode calorimétrique simplifiée, nous montrons que la méthode électrique est adaptée à l’estimation des pertes de commutation mais nécessite beaucoup d’attention. En raison de mobilité élevée des porteurs de charge dans le SiC, nous montrons que le BJT SiC ne nécessite pas l’utilisation de diode d’anti-saturation. Enfin, aucune variation significative des pertes de commutation n’a pu être constatée sur une plage de température ambiante variant de 25°C à 200°C.La quatrième partie concentre l’étude du comportement de MOSFET SiC sous contraintes HTRB (High Temperature Reverse Bias) et dans une application diode-less dans laquelle les transistors conduisent un courant inverse à travers le canal, exception faite de la phase de temps mort pendant laquelle c’est la diode de structure qui assurera la continuité du courant dans la charge. Les résultats montrent que la diode interne ne présente aucune dégradation significative lors de la conduction inverse des MOSFET. Le MOSFET Cree testé montre une dérive de la tension de seuil et une dégradation de l’oxyde de grille qui sont plus significatives lors des essais dans l’application diode-less que sous des tests HTRB. La dérive de la tension de seuil est probablement due au champ électrique intense régnant dans l’oxyde et aux pièges de charge dans l'oxyde de grille. / My PhD work in laboratories SATIE of ENS de Cachan and Ampère of INSA de Lyon is a part of project GEstioN OptiMisée de l’Energie (GENOME) to investigate the potential of some Silicon carbide (SiC) power devices (JFET, MOSFET and BJT) in power electronic converters dedicated to aeronautical applications for the development of more electric aircraft.The first part of my work investigates the robustness of MOSFET and SiC BJT subjected to short circuit. For SiC MOSFETs, under repetition of short-term short circuit, a gate leakage current seems to be an indicator of aging. We define repetitive critical energy to evaluate the robustness for repetition of short circuit. The effect of room temperature on the robustness of SiC MOSFET and BJT under short circuit stress is not evident. The capability of short circuit is not improved by reducing gate leakage current for MOSFET, while BJT shows a better robustness by limiting base current. For MSOFET, a significant increase in gate leakage current accelerates failure for DC voltage from 600V to 750V. After opening Rohm MOSFETs with a short circuit between gate and source after failure, the fusion of metallization is considered as the raison of failure. In this particular mode of failure, the short circuit between gate and source self-protects the chip and opens drain short current.The second part of the thesis is devoted to the study of SiC JFET, MSOFET and BJT in avalanche mode. The SemiSouth JFET and Fairchild BJT exhibit excellent robustness in the avalanche. On the contrary, the avalanche test reveals the fragility of Rohm MOSFET since it failed before entering avalanche mode. The failure of Rohm MOSFET and its low robustness in avalanche mode are related to the activation of parasitic bipolar transistor. The avalanche current is a very small part of the current in the inductor. It flows from the drain/collector to the gate/base to drive the transistor in linear mode. A high-value gate resistance effectively reduces the avalanche current through the drain-gate junction to the JFET.The third part of this thesis concerns the study of switching performance of SiC BJT at high switching frequency. We initially attempted to validate the switching loss measurements. After checking the accuracy of the electrical measurement compared to calorimetric measurement, electrical measurement is adopted for switching power losses but requires a lot of attention. Thanks to high carrier charge mobility of SiC material, SiC BJT does not require the use of anti-saturation diode. Finally, no significant variation in switching losses is observed over an ambient temperature range from 25°C to 200°C.The fourth part focuses on the study of SiC MOSFET behavior under HTB (High Temperature Reverse Bias) and in diode-less application in which the transistors conduct a reverse current through the channel, except for the dead time during which the body diode ensure the continuity of the current in the load. The results show that the body diode has no significant degradation when the reverse conduction of the MOSFET. Cree MOSFET under test shows a drift of the threshold voltage and a degradation of the gate oxide which are more significant during the tests in the diode-less application than under HTRB test. The drift of the threshold voltage is probably due to intense electric field in the oxide and the charge traps in the gate oxide.

This thesis presents a novel power side-channel DAC (PS-DAC) which is constructed from user-controllable short circuits in FPGAs and which manipulate overall system power through dynamic power dissipation. Alternately, similar PS-DACs are created using shift-register primitives(SRL16E) which manipulate system power through switching logic, for means of comparison with short-circuit-based PS-DACs. PS-DACs are created of various sizes using both short-circuit-based and shift-register-based methods. These PS-DACs are characterized in terms of output linearity,monotonicity, and frequency distortion. Applications explored in this thesis which use PS-DAC technology include a Simple Power Analysis (SPA) side-channel transmitter, and a frequency watermarking application. These applications serve as proof-of-concept for PS-DAC use in sidechannel communication applications.

Forskning kring tjock representation är knapp och en aspekt som har negligerats i debatter kring inkluderande och mångfald. Syftet med denna uppsats är därför att undersöka hur vår samtid, i en engelskspråkig kontext, ser på tjockhet i film och tv. Detta utforskas genom fallstudien Reflect, en animerad kortfilm från 2022. Fallstudien är vald då Reflect omskrivs i media som Disneys första film med en tjock huvudkaraktär. Uppsatsen ämnar besvara hur Disney har porträtterat och hanterat den tjocka huvudkaraktären i Reflect, samt hur denna kortfilm har mottagits och vilka diskussioner som den har väckt. Detta görs genom att närläsa filmen samt analysera dess mottagande på filmdatabaser, sociala medier och i massmedia. Resultaten diskuteras med hjälp av teorier inom representation, socialkonstruktionism, fat studies och mottagandeteori. Resultaten visar att filmen porträtterar huvudkaraktären som en tjock karaktär vars kroppsstorlek gör att hon sticker ut. Detta leder till självtvivel som hon övervinner på ett självständigt sätt. Resultaten visar vidare att mottagandet både är positivt och negativt och att diskussioner har väckts kring sättet som Disney väljer att fokusera på en tjock karaktär.

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Nowadays, major public concern is concentrated on reducing the usage of fossil fuels and reducing emissions of CO₂ by different energy advancement. Electric vehicle technology presents extremely effective way of reducing carbon emissions and paves the way of having sustainable and renewable energy future. In order to wear the cost of electric vehicles down, batteries have to be improved as well as higher power density and high reliability has to be achieved. This research work mainly focuses on achieving higher power density and higher reliability of the inverter stage by utilizing wide-bandgap SiC MOSFET semiconductor devices in electric vehicle application. In order to achieve higher reliability of the inverter stage, high bandwidth, high performance Rogowski coil switch current sensors are employed. These sensor were embedded on the PCB and integrated on the gate driver. High bandwidth switch current sensor measurement is used for fast short-circuit detection and protection of the SiC MOSFET semiconductor switches. Furthermore, comparison with conventional detection and protection method used in automotive IGBT applications is shown where novel protection showed superior performance. This thesis also shows principle of how to obtain phase currents of the system using Rogowski coil switch current sensor measurements. Digital reconstruction principle is employed to obtain the phase currents. Accurate and linear current sensor is achieved. By successfully realizing this integrated phase current measurement on the gate driver, elimination of the commercial current sensors from the system is possible. By eliminating existing phase current sensors, higher power density could be achieved. Sensor is evaluated in both continuous and discontinuous PWM schemes. / Master of Science / Together with renewable sources, electric vehicle will play an important role as a part of sustainable and renewable energy future by significantly reducing emissions of CO₂ into the atmosphere. In order to make electric cars more acceptable and accessible and make a significant impact on the environment, cost must be lowered down. To wear the cost of the electric vehicles down, powertrain of the car must be significantly improved and made smaller as well as lighter. This thesis mainly focuses on improving the reliability of the motor driving stage by implementing novel protection during fault periods such as short-circuit event. Furthermore, this novel protection allows current sensing that is crucial for motor control during normal operation periods. This will enable more compact motor driving stage since existing current sensing elements can be eliminated.

This thesis focuses on the connectivity problems of the new sources to the electrical network. The first part of the thesis deals with the description of the new source and the method of its connection to the electrical network. Furthermore, in work, there are elaborated the blocking conditions for substation TR Neratovice expanded distribution point. A distribution network operator must receive an attachment application for connecting before the actual connection. The attachments consist of study cases of conjunction that values the inverse influence on the distributional network and informs the operator about the required measures for the reliable service with the new source. PSS Sincal computer software was used to survey the inverse influences on the distributional network. Based on processed data, the evaluation of conjunction of the synchronous generator to the grid at TR Neratovice substation was reconsidered.