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1	Design and Implementation of a High Frequency Flyback Converter / Design and Implementation of a High Frequency Flyback Converter Ahmad, Nisar January 2014 (has links) The power supply designers choose flyback topology due to its promising features of design simplicity, cost effectiveness and multiple outputs handling capability. The designed product based on flyback topology should be smaller in size, cost effective and energy efficient. Similarly, designers focus on reducing the circuit losses while operating at high frequencies that affect the converter efficiency and performance. Based on the above circumstances, an energy efficient open loop high frequency flyback converter is designed and operated in MHz frequency region using step down multilayer PCB planar transformer. The maximum efficiency of 84.75% is observed and maximum output power level reached is 22.8W. To overcome the switching losses, quasi-resonant soft switching technique is adopted and a high voltage CoolMOS power transistor is used. Flyback Converter Quasi-Resonant Soft Switching Technique.
2	Přenosný zdroj pro indukční ohřev / Portable source for induction heating Nevřela, Tomáš January 2018 (has links) The aim of this work is to realize and test a prototype portable source for induction heating of small parts. The project contains a theoretical basis of resonant circuits and induction heating. The device design is based on simulation results from the FEMM program, with which a focussing coil for induction heating has been designed. The parts of the thesis are the realization of the designed device, its putting into operation and the programming of the control.
3	Design Of A Zvs Qrc Converter For Educational Test Bench Senguzel, Ismail 01 December 2006 (has links) (PDF) In this thesis, the conventional pulse-width modulated (PWM) and zero-voltage switching (ZVS) quasi-resonant buck converters are analyzed and a variable-frequency control technique is proposed to regulate the output voltage due to the immediate input line and load changes. The quasi-resonant technique provides favorable switching conditions for active switch to reduce switching losses and electromagnetic interference (EMI). The method is based on shaping the voltage across the active switch in quasisinusoidal fashion and the switching action occurs with nearly zero voltage across the active switch. This requires only two additional components to the conventional PWM buck converter. The proposed quasi-resonant converter is capable of operating in megahertz range with a significant improvement in performance and power density. Detailed analytic and small-signal models of the ZVS quasi-resonant buck converter are established and the switching behavior is investigated in order to provide nearly zerovoltage turn-on. The performance of the ZVS quasi-resonant technique is verified with the computer simulations. The results are compared with the experiments in the laboratory involving both the open-loop and closed-loop operations. The detailed experiment procedure is added to use this converter for educational purposes.
4	Dvojčinný kvazirezonanční DC/DC měnič s transformátorem / Push-pull quasi-resonant DC/DC converter with a transformer Dvořák, Petr January 2020 (has links) This diploma thesis deals with analysis of function and subsequent construction of a quasi-resonant DC / DC converter 300 V / 50 V for an output of about 1.5 kW. The aim of this work is to test and describe the behavior of an experimental converter at various operating parameters. In the theoretical part, resonant circuits are described, as well as our connection of the resonant converter. Based on the used topology and the simulated behavior of the converter, the individual components of the power circuit and its control and excitation circuit are designed in Chapters 4 and 5. The sixth chapter deals with the construction and testing of the converter, including a description of its behavior. The last chapter contains technical documentation.
5	Ultracapacitor/Battery Hybrid Energy Storage Systems for Electric Vehicles Moshirvaziri, Mazhar 22 November 2012 (has links) This thesis deals with the design of Hybrid Energy Storage System (HESS) for Light Electric Vehicles (LEV) and EVs. More specifically, a tri-mode high-efficiency non-isolated half-bridge converter is developed for the LEV based HESS applications. A 2 kW, 100 V interleaved two-phase converter prototype was implemented. The peak efficiency of 97.5% and a minimum efficiency of 88% over the full load range are achieved. Furthermore, a power-mix optimizer utilizing the real-time Global Positioning System (GPS) data for the EV based HESS is proposed. For a specific design, it is shown that at the cost of less than 1.5% of the overall energy savings, the proposed scheme reduces the peak battery charge and discharge rates by 76% and 47%, respectively. A 30 kW bi-directional dc-dc converter is also designed and implemented for future deployment of the designed HESS into a prototype EV, known as A2B. Ultracapacitor Battery Electric Vehicle Hybrid Energy Storage System Light Electric Vehicle Half-bridge Converter DC-DC Converter Quasi Resonant Pulse Frequency Modulation Variable Frequency Quasi-resonant Zero Voltage Switching High Efficiency Power Mix Optimizer Global Positioning System GPS Bi-directional DC-DC Converter A2B Project EVE 0544
6	Ultracapacitor/Battery Hybrid Energy Storage Systems for Electric Vehicles Moshirvaziri, Mazhar 22 November 2012 (has links) This thesis deals with the design of Hybrid Energy Storage System (HESS) for Light Electric Vehicles (LEV) and EVs. More specifically, a tri-mode high-efficiency non-isolated half-bridge converter is developed for the LEV based HESS applications. A 2 kW, 100 V interleaved two-phase converter prototype was implemented. The peak efficiency of 97.5% and a minimum efficiency of 88% over the full load range are achieved. Furthermore, a power-mix optimizer utilizing the real-time Global Positioning System (GPS) data for the EV based HESS is proposed. For a specific design, it is shown that at the cost of less than 1.5% of the overall energy savings, the proposed scheme reduces the peak battery charge and discharge rates by 76% and 47%, respectively. A 30 kW bi-directional dc-dc converter is also designed and implemented for future deployment of the designed HESS into a prototype EV, known as A2B. Ultracapacitor Battery Electric Vehicle Hybrid Energy Storage System Light Electric Vehicle Half-bridge Converter DC-DC Converter Quasi Resonant Pulse Frequency Modulation Variable Frequency Quasi-resonant Zero Voltage Switching High Efficiency Power Mix Optimizer Global Positioning System GPS Bi-directional DC-DC Converter A2B Project EVE 0544

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