• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
• /
• 제11B권4호
• /
• pp.180-184
• /
• 2001

The high operation frequency mainly reduces transformer volume in the power supply. A high frequency and high voltage pulse transformer is designed, fabricated, and tested. Switching frequency of the transformer is 100 kHz. Input and output voltages of the transformer are 250 V and 4 kV, respectively. Normal operation power of the transformer is 3 kW. Maximum volume of the transformer is 400 $cm^3$. The power density is thus 7.5 W/$cm^3$. The transformer will be installed in a metal box that has nominal operation temperature of 85 degree centigrade. The transformer and other high voltage components in the box will be molded with Silicon RTV(Room Temperature Vulcaniza) that has a very low thermal conductivity. Procedure of design and test results are discussed. Analytical as well as experimental results of varous paramters such as transformer loss, leakage inductance, distributed capacitance are also discussed. In addition, thermal analysis results from ANSYS code for three different operation conditions are discussed.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1999년도 하계학술대회 논문집 D
• /
• pp.1581-1583
• /
• 1999

Epoxy Compound has been used as insulation material in cable accessories. During the applying voltage to cable, heat shock is induced to accessory by the temperature difference between atmosphere and conductor. In this study, crack resistance, thermal and mechanical properties were evaluated about conventional epoxy compound and rubber toughened epoxy compound. Because rubber absorbs the stress caused by heat shock, crack resistance of rubber toughened epoxy compound is high. In the case of low thermal expansion coefficient, the compound shows high crack resistance because of low volumetric change.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2009년도 추계학술대회 논문집
• /
• pp.51-51
• /
• 2009

In this paper, we proposed GaN trench Static Induction Transistor(SIT). Because The compound semiconductor had superior thermal characteristics, GaN and SiC power devices is next generation power semiconductor devices. We carried out modeling of GaN SIT with 2-D device and process simulator. As a result of modeling, we obtained 340V breakdown voltage. The channel thickness was 3um and the channel doping concentration is 1e17cm-3. And we carried out thermal characteristics, too.

• Journal of international Conference on Electrical Machines and Systems
• /
• 제2권4호
• /
• pp.413-420
• /
• 2013

This paper includes the results of the electromagnetic finite element analysis with regard to overheating problem of the power cable tray due to asymmetric magnetic flux density. This phenomenon was experienced in the utility power plant, Korea. The influences of the power cable arrangements and material of the tray were analyzed to find the best solutions using the eddy current-thermal coupled analysis.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2001년도 춘계학술대회논문집D
• /
• pp.589-595
• /
• 2001

The present study conducted heat transfer analysis in multi-layer of CD-R. It is necessary to analyze heat transfer during the recording process to find optimum power and write strategy in CD-R. This study investigated effects of several parameters such as recording speed, laser power, layer thickness and thermal property. The calculated results presented temperature distribution in the multi-layer and detailed information of recording characteristics. Optimum laser power was estimated, comparing an optimum mark length with the calculated mark lengths. The results showed that the optimum laser power was influenced significantly by the layer thickness and the thermal properties of the dye.

• 전력전자학회논문지
• /
• 제9권3호
• /
• pp.203-212
• /
• 2004

히트파이프를 이용하는 전력반도체 냉각용 히트파이프가 장기간 사용에도 안정된 작동을 이루도록 하기 위해서는 제조 과정에서 발생할 수 있는 산화막 존재 등 문제 요인의 제거와 함께 시험을 통한 확인이 필요하다. 본 연구에서는 전력반도체 냉각용 히트파이프가 요구하는 여러 기하학적, 열적조건에 의해 결정되는 열수송 한계 및 특성과 안정된 작동을 확인하기 위한 시험방법을 제시하고 시험을 통하여 확인된 결과를 정리하였다.

• 한국지능시스템학회:학술대회논문집
• /
• 한국퍼지및지능시스템학회 2003년도 ISIS 2003
• /
• pp.350-353
• /
• 2003

In this paper, we proposed the method to design fuzzy controller using the experience of the operating expert and experimental numeric data for the robust control about the noise and disturbance instead of the traditional PID controller for the main steam temperature control of the thermal power plant. The temperature of main steam temperature process has to be controlled uniformly for the stable electric power output. The process has the problem of the hunting for the cases of various disturbances. In that case, the manual action of the operator happened to be introduced in some cases. We adopted the TSK (Takagi-Sugeno-Kang) model as the fuzzy controller and designed the fuzzy rules using the informations extracted directly from the real plant and various operating condition to solve the above problems and to apply practically. We implemented the real fuzzy controller as the Function Block module in the DCS(Distributed Control System) and evaluated the feasibility through the experiment81 results of the simulation.

• 한국전기전자재료학회논문지
• /
• 제22권12호
• /
• pp.1018-1022
• /
• 2009

In this paper, we proposed GaN trench Static Induction Transistor(SIT). Because The compound semiconductor had superior thermal characteristics, GaN and SiC power devices is next generation power semiconductor devices. We carried out modeling of GaN SIT with 2-D device and process simulator. As a result of modeling, we obtained 340 V breakdown voltage. The channel thickness was 3 urn and the channel doping concentration is $1e17\;cm^{-3}$. And we carried out thermal characteristics, too.

• 한국신재생에너지학회:학술대회논문집
• /
• 한국신재생에너지학회 2006년도 추계학술대회
• /
• pp.180-183
• /
• 2006

As a final step for developing a small-scale solar thermal power generation technology, a demonstration project for a dish-stirling power system has been carried out by KIER. During the two years project period, 10kW solar-only power system was built in Jinhae city and successful solar operations were demonstrated. In this paper an example of typical clean day operation and analysis results was introduced.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2000년도 추계학술대회논문집B
• /
• pp.656-661
• /
• 2000

In the recent trend of electric power supply market, a variable pressure operation supercritical once-through steam generator is highlighted as a thermal power plant for cycling load because of its superiority in load regulation. Almost all thermal power plants of the future are expected to be variable pressure operation supercritical once-through units. APESS(Advanced Plant Engineering & Simulation System) is a dynamic simulation software for power plant which is under being developed by Korea Heavy Industries & Construction Co., Ltd. This paper present the introduction of APESS and the result of simulation for variable pressure operation supercritical once-through steam generator.