• Journal of Power Electronics
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• v.10 no.3
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• pp.228-234
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• 2010

This paper investigates the conducted-noise characteristics of a digitally-controlled randomly-switched dc-dc converter. In order to investigate the effect of the suggested digital controller on the conducted-noise characteristics of a dc-dc converter, three factors have been studied: the field-programmable gate array (FPGA) clock speed, the randomization ratio percentage, and the effect of using a closed loop feedback controller. A field-programmable gate array is much more flexible than analog control circuits, has a lower cost, and can be used for power supply applications. A novel FPGA-based implementation has been suggested for obtaining the experimental validations and realizing the studied concepts. Furthermore, the experimental results have been discussed and design guidelines have been included.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.333-336
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• 2003

The current paper presents the design and implementation of a low-profile dc-to-dc converter developed as a power supply for the sustain driving circuit inside large-area wall-mount ac PDP application systems. Details on the design and implementation of a 500 W prototype dc-to-dc converter, miniaturized within a 230 $mm{\times}130$ mm area with a thickness of 25 mm while still achieving a 95 % conversion efficiency, are presented to demonstrate the feasibility and application potentials of the proposed low-profile dc-to-dc converter.

• Proceedings of the KIEE Conference
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• 1999.07f
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• pp.2665-2667
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• 1999

This Paper proposes a new toplogy snubber circuit of Full-Bridge DC-DC Converter for reducing conduction losses and snubber circuit heating loss. Using Partial Resonent Soft Switching Method and Clamping, studying on a new snubber circuit for reducing losses that a snubber circuit heating loss in the secondly diode rectification side, a switching losses in the primary side of IGBT inverter and conduction losses in the high frequency insulation transformer. In this paper, we present FB DC-DC converter included a new lossless snubber circuit, and then be analyzed and simulated.

• Proceedings of the KIEE Conference
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• 1999.07f
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• pp.2515-2517
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• 1999

In this paper we analysis DC bus voltage stress at high line voltage and light load in $S^4$-PFC Isolated AC/DC converter with DC bus voltage feedback using coupling in transformer. In this converter, the principle of operation and the practical problems in the design are considered. Simulation and experimental results are presented to verify the operation and performance of the $S^4$-PFC converter with DC bus voltage feedback. Experimental sets are performed in the conditions; switching frequency 100 kHz, output of 5 V, 60W, and universal line input voltage.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.599-600
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• 2008

This paper presents a high performance DC-DC boost converter by current-mode control method. As load current change, the converter change PWM/PFM operation automatically. current-mode DC-DC boost converter is implemented in a standard $0.35{\mu}m$ CMOS process. The peak efficiency was 94 % with a switching frequency of 1.2MHz.

• Journal of Advanced Marine Engineering and Technology
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• v.40 no.5
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• pp.429-436
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• 2016

Currently, many studies on green ships are under way. Fuel cell (FC) ships are of interest as future low-emission, fuel-efficient vessels. In this paper, a hybrid power management system for an FC ship was designed. The system consists of an FC, a battery, a unidirectional DC/DC converter, a bidirectional DC/DC converter, a filter, an inverter, and a propulsion component. To design the system, we analyze electric sources and converters, and create PLECS models of hybrid power management system. Then, we check the cold start sequence and perform a simulation to understand the characteristics of the hybrid power management system in an FC ship.

• Proceedings of the KIEE Conference
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• 2004.04a
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• pp.159-162
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• 2004

The paper proposes the coupled inductor rectifier of Three Level DC/DC converter CICDR-TL(Coupled Inductor Current Doubler Rectifier-Three Level) achieves Zero Voltage Switching (ZVS) for the switches in a wide load range and Zero Current Switching (ZCS) in a light load range. Advantages and disadvantages of this topology compared to the conventional Center Tapped TL Converter are discussed. Experimental evaluation results obtained on a 27V 60A DC/DC converter prototype for the 1.8kW 40kHz IGBT based experimental circuit.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.10
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• pp.1845-1849
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• 2010

We have proposed and fabricated a Buck-Boost DC to DC Converter for Thermoelectric generator (TEG) with constant output voltage suitable for battery chargers or constant voltage supplies in the range of several watt. The experimental and simulation results have shown that the proposed method allows stable operation with maximum 86% power transfer efficiency. The proposed circuit has a merit in cost and miniaturization of a system compared to conventional MPPT algorithms, because the proposed method adopts only analog circuit without DSP or micro controller unit for calculating peak power point by iterative methods.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.928-929
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• 2008

A dc/dc power conversion system using multi stage capacitor is proposed in this paper. The proposed new type converter is designed from high efficiency dc/dc converter with fixed boost ratio and variable voltage converter. The tests have been done using PSIM computer simulation to confirm the analysis and control concept.

• Proceedings of the KIPE Conference
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• 1998.10a
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• pp.1042-1046
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• 1998

A new soft switching isolated bi-directional phase shifted pulse width modulation (PSPWM) dc/dc converter is presented. Due to the use of the energy recovery snubber, the isolated bi-directional PSPWM dc/dc converter has a significant reduction of switching losses in the switching devices of the primary and secondary side bridge, respectively. The proposed soft switching bi-directional PSPWM FB dc/dc converter provides an energy recovery snubber which consists of two fast recovery diodes, a resonant capacitor and a resonant inductor. The complete operating principles and simulation results will be presented.