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11	Trakční měniče velkých výkonů / High power traction converters Žižka, Pavel January 2008 (has links) This master thesis is based on realization of the previous university project, design of locomotive reconstruction and solving accompanying problems. In this thesis there are described all parts of a converter. The end of thesis involved theory about driver circuits of power transistors IGBT. Nowadays is still more often to think about reconstruction of the old technology rather than design a complete new construction. Investors take this decision from the financial reasons and because to the old technology designer can add only the converter. In this instant we talk about electrical locomotive, there should be kept a supply transformer and a driving unit (DC engine). The aim of this thesis is to design the converter between these two basic parts. The converter must taking the quasi-sinusoidal current which is in the phase with the input voltage, also must be able to control the engine and recuperate energy back to the network. For realization of these conditions, the converter must contain the active rectifier working in the DC-link and from which the step-down DC/DC converter is fed. Converter output is connected to the driving unit. The digital control of the power transistors is provided by processor MOTOROLA DSP56F. The control impulses, switching the power transistors, go through the driver circuits to transistors. All problems are described in the following text.
12	Návrh a realizace aktivního trojfázového usměrňovače / Concept of three-phase active rectifier Bareš, Jiří January 2016 (has links) This work deals with three-phase active rectifier control. In first, theoretical part it describes several control strategies with focus on voltage oriented control. For this type of control a design is worked out, and created model and its simulation is described. Second, practical part deals with realisation on microcontroller TMS320F28335, which is main processing unit of device lent by company Elcom. Therefore in this part abilities and settings of the controller along with developped control algorithm are described. Reached results of measurement are then presented and in the conclusion they are evaluated.
13	Evaluation of power quality and common design concept for AC-DC converters in aircraft Brolund, Andreas January 2017 (has links) This master thesis has been carried out in collaboration with Saab, Avionics Systems in Jönköping, Sweden, during the spring of 2017. The thesis investigates unidirectional rectifier topologies in aircraft and the focus has been on evaluating the power quality requirements according to the aircraft standards, in the course of the More Electric Aircraft concept. Both passive and active power factor correction topologies are considered, discussed and compared. Simulation models are designed in MATLAB/Simulink and the procedures are presented. A modular concept regarding components is discussed where different power supplies and loads are considered. The simulations present both a passive 12-pulse auto-transformer rectifier unit and an active Delta-switch rectifier fulfilling requirements for aircraft such as the total harmonic distortion of the supply current. In addition, the input power factor is close to unity and an efficiency greater than 97% is obtained. Lastly, future aspects of each topology are discussed and necessary improvements to obtain realistic simulation models are presented. AC-DC converter aircraft power electronics MOSFET MEA More electric aircraft Delta-switch ATRU Auto-transformer rectifier unit Auto-transformer Vienna rectifier passive rectifier active rectifier power factor correction APFC PFC MATLAB Simulink THD total harmonic distortion Elektroteknik och elektronik
14	Capacitive Wireless Power Transfer to Biomedical Implants: Link Design, Implementation, and Related Power Management Integrated Circuitry Erfani, Reza 02 September 2020 (has links) No description available. Electrical Engineering Biomedical Research Biomedical Engineering Design Electromagnetics Energy Engineering Health Care Biomedical implants transcutaneous wireless power transfer wireless powering capacitive wireless power transfer capacitive link biosafety power management integrated circuit PMIC CMOS active rectifier IC CMOS dual-output regulating rectifier IC

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