• 한국연소학회:학술대회논문집
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• 한국연소학회 2012년도 제45회 KOSCO SYMPOSIUM 초록집
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• pp.49-51
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• 2012

In this paper, the integration issue, such as an air-side integration design between the gas turbine and air separation unit, is described and analyzed by the exergy and energy balance of the combined-cycle power block in an IGCC power plant. The results showed that the net power of the system was almost same, but that of the gas turbine was decreased as the integration degree increased. The highest exergy loss was occurred in the combustor of gas turbine, which was affected by the chemical reaction, heat conduction, mass diffusion, and viscous dissipation.

• 대한설비공학회지:설비저널
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• 제17권2호
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• pp.131-139
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• 1988

The thermoacoustic oscillation induced in an air column with variable cross section area is investigated theoretically and experimentally. The onset condition of the oscillation is derived by equating the acoustic power production to the power dissipation. The power production at the heater is predicted by using the efficiency factor obtained by heat transfer analysis for a single wire in a uniform cross flow and considering the interference between heater wires. The power dissipation is estimated by measuring the attenuating coefficient from the pressure decay curve. The theoretical prediction to the onset condition of the oscillation is confirmed experimentally. The effect of the variation of the column cross section area on the onset condition is presented.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2011년 춘계학술대회논문집
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• pp.240-242
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• 2011

Wind power system is generally divided into the onshore wind turbine and the offshore wind turbine according to site locations. The offshore wind turbine is manufactured as a closed nacelle cooling system including a heat exchanger to prevent corrosion, but the onshore wind turbine is manufactured as open nacelle cooling system dependent on only the outdoor air without a heat exchanger. The indoor of a nacelle which is composed of a generator, foil power converters and a gearbox with a lot of heat is very narrow and airtight. This aim of the study is to demonstrate the temperature effect depending on positions of air-supply and exhaust ports. And this study discusses the flow field and removal efficiency of heat caused by components.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.258-261
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• 2001

High Power factor Active Filter converter is used for Inverter Air conditioner power supply to meet IEC standard. In the active filter topology for power factor, extra switch just control the input current indirectly to meet the IEC standard for reducing the cost and size. In this paper, low cost converter was suggested by simulation using extra switch which auxiliary pulse is inserted and quasi resonant soft switching topology control is adapted for panel's inverter air conditioner converter Inserting auxiliary Pulse method to the extra switch has the benefit of reducing THD by low cost input control circuit. And also quasi resonant soft switching topology can reduce switching loss. So both technical is suitable for Panel's Air conditioner.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2011년도 제36회 춘계학술대회논문집
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• pp.183-186
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• 2011

본 논문에서는 전기동력 추진기관을 사용하는 비행체의 추진시스템에 대하여 분석하고, 무게분석을 통하여 PAV의 전기동력시스템을 살펴보았다. 현재 1,000 kg의 PAV를 개발할 경우 PEMFC와 리튬전지를 조합한 추진기관이 내연기관을 대체할 수 있을 것으로 예상된다. 내연기관을 대체하기 위해서는 연료전지 출력밀도 2.5 kW/kg, 배터리 에너지밀도 0.75 kWh/kg 이상의 성능이 요구된다.

• 전력전자학회논문지
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• 제4권1호
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• pp.105-110
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• 1999

이 논문은 역률제어회로를 갖는 인버터 구동 에어컨에 관해 설명한다. 정류기에 역률제어회로를 적용함에 의해서 전원선으로의 고조파 삽입을 줄일 수 있고, 효율을 향상시킬 수 있으며, 기존의 인버터와 비교해서 전체 시스템 가격을 낮출 수 있다. 또한, 역률제어회로의 출력전압을 안정화함에 의해서 시스템 성능을 향상시킨다. 본 논문에서는 역률제어회로의 자세한 설계절차를 제시하고, 역률제어회로의 여러 가지 장점을 시뮬레이션과 실험을 통해서 확인하였다.

• Journal of Power Electronics
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• 제10권3호
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• pp.293-299
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• 2010

In this paper, a single-phase PFC (Power Factor Correction) dual boost converter based on input voltage estimation is studied for DC inverter air conditioner. It is focused on improving input power factor and power quality to satisfy the recent harmonic current regulation standards. Furthermore the input voltage estimation is introduced for price competitive products. A low cost and reasonable control system is implemented using a specified high-speed 32-bit microprocessor. Their effectiveness are verified through theoretical analysis and experiments.

• 전자공학회논문지A
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• 제32A권12호
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• pp.136-141
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• 1995

GaAs power MESFETs with 1 .mu.m gate length and an undoped GaAs surface layer on the doped GaAs channel are fabricated using IR(image reversal) and air-birdge processes. And then We have measured and calculated DC and RF characteristics. We have obtained saturation current 107-500 mA (197-255 mA/mm), maximum linear RF output power 111-518.8 mW (204-270 mW/mm), current gain cut-off frequency 7-10 GHz, maximum unilateral transducer power gain 5.7-12.7, and power added efficiencies 37.9-41.2 % from the devices with gate width 0.45-2.2 mm, at 6 GHz.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 학술대회 논문집 전문대학교육위원
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• pp.6-8
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• 2002

Generally in solar air conditioning system, the diode rectifier is used to build up DC link voltage from AC source. The diode rectifier is simple and cheap but it brings out the problems of low power factor and plentiful harmonics at the AC source. Also It can degrade the utilization rate of solar energy because the reverse of power flow cannot be made. Hence, in this paper to overcome the peak power problems in summer and to endure good AC input characteristics, solar air conditioning system using the PWM converter is proposed. A high input power factor of 97[%] and an efficiency of 98[%] are also obtained. The harmonic guide lines of proposed rectifier is no interfered with inverter switching, resulting in a simple, reliable and low cost ac to dc converters in comparison with the boost type current improving circuits.

• 전력전자학회논문지
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• 제27권3호
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• pp.180-191
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• 2022

In this paper, a single-stage alternating current (AC)-DC converter is proposed for the automated-guided vehicle wireless charging system. The proposed converter is capable of soft-switching under all input voltage (VAC: 220 Vrms ± 10%), load conditions (0-1 kW), and air gap changes (40-60 mm) by phase control at a fixed switching frequency. In addition, controlling a wide output voltage (Vo: 39~54 VDC) is possible by varying the link voltage and improving the input power factor and the total harmonic distortion factor. Experimental results were verified by making a prototype of a 1-kW wireless power charging system that operates with robustness to changes in air gaps.