• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.249-252
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• 2002

Recently, the advanced countries are using the corrosion monitoring system in a chemical plant and an oil tank in order to protect the corrosion because it leads to a big accident, pollution of soil. and lose of money Generally. the owners of the facilities adopt CP(Cathodic Protection) systems to protect the corrosion also. However, a CP system for oil tank was not considered in Korea Moreover they didn't adopted a corrosion monitoring system. In this paper, we have been developed not only the remote automatic corrosion monitoring but also the remote corrosion control system using the high efficiency CP rectifier. This results should be used to operate the CP system effectively and economically. And also it will be possible to extend the expectation life of the Oil tanks.

• 반도체디스플레이기술학회지
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• 제20권4호
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• pp.108-113
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• 2021

In this paper, a totem pole PFC was structured in two methods with FET and diode for low-speed switch while GaN FET was used for high-speed switch. Internal power loss, power conversion efficiency and steady-state characteristics of the two methods were compared in the totem pole bridgeless PFC circuit which is widely applied in large-capacity and high-efficiency switching rectifier of 500W or more. In order to compare and confirm the steady-state characteristics under equal conditions, a 2kW class totem pole bridgeless PFC was constructed and the experimental results were analyzed. From the experimental results, it was confirmed that the low-speed switch operation has a large difference in efficiency due to the internal conduction loss of the low-speed switch at a low input voltage. Especially, input power factor and load characteristic showed no difference regardless of the low-speed switch operation.

• Journal of Power Electronics
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• 제5권1호
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• pp.67-75
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• 2005

A high efficiency ZVS PWM asymmetrical half bridge converter for a plasma display panel (PDP) sustaining power modules is proposed in this paper. To achieve the ZVS of power switches for the wide load range, a small additional inductor L/sub 1kg/, which also acts as an output filter inductor, is serially inserted into the transformer's primary side. At that point, to solve the problem of ringing in the secondary rectifier caused by L/sub 1kg/, the proposed circuit employs a structure without the output filter inductor, which helps the voltages across rectifier diodes to be clamped at the output voltage. Therefore, no dissipative RC (resistor capacitor) snubber for rectifier diodes is needed and a high efficiency as well as low noise output voltage can be realized. In addition, since it has no large output inductor filter, the asymmetrical half bridge converter features a simpler structure, lower cost, less mass, and lighter weight. In addition, since all energy stored in L/sub 1kg/ is transferred to the output side, the circulating energy problem can be effectively solved. The operational principle, theoretical analysis, and design considerations are presented. To confirm the operation, validity, and features of the proposed circuit, experimental results from a 425W, 385Vdc/170Vdc prototype are presented.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2004년도 전력전자학술대회 논문집(2)
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• pp.537-541
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• 2004

A high efficiency ZVS PWM asymmetrical half bridge converter for a plasma display panel (PDP) sustaining power module is proposed in this paper. To achieve the ZVS of power switches for the wide fond range, n small additional inductor $L_{lkg}$, which also acts as an output filter inductor, is serially inserted to the transformer primary side. Then, to solve the problem related to ringing in the secondary rectifier caused by $L_{lkg}$, the proposed circuit employs a structure without the output filter inductor, which helps the voltages across rectifier diodes to be clamped at the output voltage. Therefore, no dissipative RC (resistor capacitor) snubber for rectifier diodes is needed and n high efficiency as well as low noise output voltage can be realized. In addition, since it has no large output inductor filter, it features a simpler structure, lower cost, less mass, and lighter weight. Moreover, since all energy stored in $L_{lkg}$ is transferred to the output side, the circulating energy problem can be effectively solved. The operational principle, theoretical analysis, and design considerations are presented. To confirm the operation, validity, and features of the proposed circuit, experimental results from a 425W, 385Vdc/170Vdc prototype are presented.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2000년도 전력전자학술대회 논문집
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• pp.299-304
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• 2000

In this paper we investigate accurately the input-output characteristic of single-phase diode rectifier. The diode rectifier has some advantages of simplicity cost and high-efficiency. But it has some defects which THD of input current low PF and voltage drop of output side. In order to compensate it we analyzed using the parameter variation and introduced capacitor insertion method for reducing the distortion and increasing the PF.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.182-185
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• 2005

This paper presents a new voltage current driven method for the synchronous rectifier (SR) in a flyback topology. The proposed synchronous rectfier of voltage-current driven can operate at wide load range with high efficiency. The gate voltage of FET in the synchronous rectifier is easily controlled by resistor ratio. regardless of line and load fluctuation. The 200W (l2V/17A) prototype is built and achiveved efficiency as high as 90% at 4A, 93.2% at 7A and full load.

• 전기학회논문지
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• 제67권12호
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• pp.1602-1610
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• 2018

Induction heating can convert electrical energy to thermal energy with high conversion efficiency and quick heating. Currently, a current source rectifier/inverter-fed parallel resonant circuit is widely used as an induction heating power supply for forging applications. However, the conventional induction heating power supplies composed of phase-controlled rectifier and SCR inverter have low efficiency and low power factor at input side, and require additional starting circuitry. So this paper proposes new induction heating power supply topologies for forging applications which have high power factor, high efficiency, and large output power. It also suggests detailed design guideline.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1998년도 전력전자학술대회 논문집
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• pp.265-268
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• 1998

This paper presents a soft-switching average current control PWM high power factor boost converter. Conventional boost ZVT-PWM converter has a disadvantage of hard-switching for auxiliary switch at turn-off. A soft switched auxiliary switch is proposed to achieve a high performance ZVT-PWM boost rectifier. The simulation and experimental results show that soft switching operation can be maintained for wide line and load range, which in turn improves the converter performance in terms of efficiency, switching noise and circuit reliability.

• 전기전자학회논문지
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• 제22권2호
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• pp.393-401
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• 2018

이 논문에서는 WPC / A4WP 무선 전력 전송을 위한 정류기가 설계하였다. 설계된 정류기는 WPC (무선 전력 컨소시엄) 및 A4WP (무선 전력 연합)를 모두 지원하며 전파 브리지 정류기로 설계되었다. WPC는 100kHz ~ 205kHz의 주파수에서 전력을 전송하고 A4WP는 6.75MHz의 주파수에서 전력을 전송한다. 브리지 정류기는 다이오드 대신 MOSFET을 사용하기 때문에 출력 전압이 입력 전압보다 높으면 역전류가 흐르고 효율에 영향을 미친다. 따라서 MOSFET을 통해 흐르는 전류를 감지하고 역전류를 차단하는 역전류 검출기를 추가했다. 주파수 판별기는 주파수 대역이 다르기 때문에 사용된다. 설계된 정류기는 CMOS $0.35{\mu}m$ 고전압 공정을 사용하여 설계되었다. 입력 전압은 최대 18V이며 100kH ~ 205kHz, 6.78MHz 주파수에서 작동한다. 최대 효율은 94.8 %이고 최대 전력 공급은 5.78W 이다.

• 한국전자파학회논문지
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• 제24권11호
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• pp.1091-1097
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• 2013

이 논문은 $0.11{\mu}m$ RF CMOS 공정에서 비대칭 몸체 바이어싱을 적용한 비교기를 사용한 정류기를 제안한다. 제안하는 정류기는 MOSFET와 두 개의 비교기로 이루어져 있다. 이 비교기는 부하 전압이 입력 전압보다 높을 때 생기는 역방향 누설 전류를 줄이는 데 사용한다. 비대칭 몸체 바이어싱을 사용함으로써 비교기의 High에서 Low 상태로 바꾸는 기준 전압을 높이고, 누설 전류가 흐르는 시간을 줄인다. 13.56 MHz의 2 Vpp 교류전압을 입력하고, $1k{\Omega}$의 저항과 1 nF의 커패시터를 부하에 연결한 환경에서 측정하였다. 시뮬레이션 결과, 전압 변환 효율은 87.5 %, 전력 변환 효율은 45 %이고, 측정한 전압 변환 효율은 85.215 %, 전력 변환 효율은 50 %이다.