• The Journal of the Korea institute of electronic communication sciences
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• v.4 no.2
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• pp.123-129
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• 2009

In this study, SMPS to drive LED traffic signal light for the railroad and airport was designed and its electrical characteristics was measured. The output voltage, output current and its power efficiencies to the input voltage 8~12VAC and 8~16VDC were 6VDC, 1.85ADC and >70%, respectively. Also the power factors of the SMPS were above 0.75 in the AC input voltage range.

• Proceedings of the KIPE Conference
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• 2001.07a
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• pp.235-238
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• 2001

A novel single-stage power factor corrected (PFC) drive for switched reluctance motor (SRM) is presented to achieve sinusoidal, near unity power factor input current. The proposed PFC SRM drive has no additional active switch. And a single-stage approach, which combines a DC link capacitor used as dc source and a drive used for driving the motor into one power stage, has a simple structure and low cost. The characteristics and validity of the proposed circuit will be discussed in depth through the experimental results.

• Journal of the Semiconductor & Display Technology
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• v.17 no.1
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• pp.21-26
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• 2018

In this paper, a multiple coupling inductor with expandable-integrated magnetic structure was proposed to enable miniaturization of external switched mode power supply (SMPS) for a large display. Inductance formula of the proposed inductor structure was derived through magnetic circuit analysis for a simple inductance designing process. The proposed inductor was applied into a 1kW class interleaved bridgeless power factor correction circuit which requires four inductors, and experimental steady state result of the circuit was compared. According to the experimental result, it was found that the proposed multiple coupling inductor shows the electrical characteristics that can replace the conventional separated inductors and is suitable for miniaturization of the SMPS since the circuit configuration is possible with one shared inductor.

• Proceedings of the KIEE Conference
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• 2002.07b
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• pp.986-989
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• 2002

This paper proposes a new single stage power factor correction (PFC) full bridge converter which operates at continuous conduction mode(CCM). The proposed single stage PFC consists of typical zero voltage switching(ZVS) full bridge DC/DC converter, two transformer auxiliary windings, and two small inductors, and two diodes. Neither additional active switch nor any control circuit are added for PFC resulting in very low cost. The proposed converter provides input power factor correction with CCM control and tight output voltage regulation. All switching devices are operated under ZVS with minimum voltage stress. Operation principle and analysis are explained and verified with computer simulation and experimental results on a 1.2kW, 100kHz prototype.

• Proceedings of the KIEE Conference
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• 2002.07b
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• pp.625-627
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• 2002

High precision voltages. currents. power factor and electrical power measurements wide range of frequency can be achieved by using the thermo-elements (thermal converters). This paper describes the development wattmeter. based on a thermal principle. The instrument has been performed measurement in the range of currents from 0 to 50 A, voltages up to 600 V, power factor 0.5. 1 and frequencies from 45 Hz to 3 kHz. The thermal converters with two heater are used in the functional element of the wattmeter.

• Journal of the Korean Institute of Telematics and Electronics
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• v.14 no.1
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• pp.23-28
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• 1977

This paper describes the practical design of a SCR inverter which is suposed to be very much suitable for high frequency induction heating power source. In this design an optimum control technique was applied to maintain constant output power and constant power factor to various heating load by the use of frequency control. Some appreciable characteristics was obtained for some design guide of large ndstrial heating power sources by the test of the 3KHz, 3KW inverter which was designed in this study.

• Proceedings of the KIEE Conference
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• 1996.07a
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• pp.255-258
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• 1996

A new low conduction loss, low cost zero-voltage-transition power factor correction circuit(PFC) is presented. Conventional PFC which consists of a bridge diode and a boost converter(one switch) always has three semiconductor conduction drops. Two switch type PFCs reduces conduction loss by reducing one conduction drop but the cost is increased because of increased number of active switches. The proposed PFC reduces conduction loss with one switch, which allows low cost. Conduction loss improvement is a little bit less than that of two switch type, but very close up. Operation and features are comparatively illustrated and verified by simulation and experimental results of 1 kW laboratory prototype.

• Proceedings of the KIPE Conference
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• 1997.07a
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• pp.247-250
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• 1997

A novel zero-voltage-switching(ZVS) isolated PWM converter for single stage power factor correction (PFC) is presented to improve the performance of the previously presented ZVT converter[5]. A simple clamp circuit in the primary side provides zero-voltage-switching condition to all semiconductor devices. This ZVS is achieved with minimum device voltage and current stresses. Operation principle, control strategy and features of the proposed converter are presented and verified by the experimental results from a 1.5 ㎾, 100 KHz laboratory prototype

• Proceedings of the KIPE Conference
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• 2011.07a
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• pp.398-399
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• 2011

본 논문에서는 단일 스위치 배전압 방식의 단상 PFC 회로의 제어기법들에 대해 기술한다. 이 PFC 회로는 저가형 이중변환방식 단상 UPS의 AC-DC 변환부에 사용할 수 있으나, 입력전류의 제어기법에 대한 연구 결과가 알려지지 않았다. 제안된 전류 제어기법들의 입력 전류 제어 성능, 입력 역률, 입력 전류의 THD를 시뮬레이션과 실험을 통해서 비교 검증하였다.

• Proceedings of the KIPE Conference
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• 2011.07a
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• pp.551-552
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• 2011

본 논문에서는 단상 이중변환 UPS의 AC-DC 변환부를 위한 단일 스위치 배전압 방식의 단상 PFC 회로의 동작특성에 대해 기술한다. 이 PFC 회로는 적은 개수의 전력용 반도체를 쓰기 때문에 비용 절감에 도움이 된다. 동작 모드에 따른 회로 각부의 전압, 전류 파형과 출력 전압 제어, 입력 역률 보상, 입력 전류 제어의 THD 억제 성능을 시뮬레이션과 실험을 통해 보였다.