• 조명전기설비학회논문지
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• 제14권2호
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• pp.52-58
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• 2000

본 논문애서는 2단 스위치 구조를 가져는 역률 보상 회로를 적용하여 도통 손실을 저감할 수 있는 새로운 결합형 1단방식 AC/DC half-bridge 컨버터에 대한 토폴라지를 제안하고, 이에 관한 전류 불연속 모드 제어와 소프트 스위칭 특성에 대하여 연구하였다. 도통손실의 저감은 기존의 역률 보상 회로 대신 새로운 형태의 이단 스위치 구조를 가지는 역률 보상 회로를 적용함으로써 이루어친다. 제안된 토폴라지의 타당성 검증을 위해서 입력전압 100[V], 출력전압 50[V]의 500[W]급 컨버터에 대한 시뮬레이션 결과를 제시하고 분석하였다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2007년도 하계학술대회 논문집
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• pp.435-437
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• 2007

Authors propose a PFC(power factor correction) Buck-Boost AC-DC converter by soft switching method. The proposed converter for a discontinuous conduction mode eliminates the complicated control requirement and reduces the size of components. The input current waveform in the converter is got to be a sinusoidal form of discontinuous pulse in proportion to magnitude of ac input voltage under the constant duty cycle switching.Therefore,the input power factor is nearly unity and the control algorithm is simple. To achieve high efficiency system, the proposed converter is constructed by using a partial resonant technique. The control switches using in the converter are operated with soft switching for a partial resonant. The control switches are operated without increasing their voltage and current stresses by the soft switching method. The result is that the switching loss is very low and the efficiency of converter is high.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.112-115
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• 2002

Previous AC/DC PFC Boost Converter perceives feed forward signal of input and feedback signal of output for average current-mode control. Previous Boost Converter, the quantity of input current will be decreased by the decrease of output current in light load, and also power factor comes to be decreased. Also the efficiency of converter will be decreased by the decrease of power factor. The proposed converter presents the good PFC(Power Factor Correction), low line current hormonic distortions and tight output voltage regulations using non-dissipative snubber. The proposed converter also has a high efficiency by non-dissipative snubber circuit. To show the superiority of this converter is verified through the experiment with a 640W, 100kHz prototype converter.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1999년도 전력전자학술대회 논문집
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• pp.319-322
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• 1999

This paper presents a novel single-stage Power Factor Corrected(PFC) AC/DC forward converter with semi-automatic current shaping in order to achieve the unity power factor and an isolated output. Since the proposed circuit is combined a boost converter used for PFCs with a forward converter used for DC to DC conversion, the over-all size of system could be reduced. And thanks to the zero voltage switching(ZVS) in both switches, the voltage stress can be reduced considerably. A simple auxiliary circuit adopted into the secondary of transformer is composed of lossless components for reducing surge voltage. A prototype which has tow IGBT(Insulated Gate Bypolar Transistor) modules as switching device is manufactured to evaluate the proposed topology. The characteristics of the proposed circuit are tested, and the validity is verified by experimental results.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.1224-1225
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• 2011

This paper proposes a novel soft-switching interleaved boost converter composed of two shunted elementary PFC boost conversion units and an auxiliary inductor. This converter is able to turn on both the active power switches at zero voltage to reduce their switching losses and evidently raise the conversion efficiency and power factor. Since the two parallel-operated elementary boost units are identical, operation analysis and design for the converter module becomes quite simple. A laboratory test circuit is built, and the circuit operation shows satisfactory agreement with the theoretical analysis. The performance of the proposed PFC rectifier was evaluated on an experimental 300[W] PFC prototype.

• Journal of Electrical Engineering and Technology
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• 제3권2호
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• pp.243-253
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• 2008

This paper deals with the analysis, design, and implementation of a single phase AC-DC Zeta converter with high frequency transformer isolation and power factor correction(PFC) in two modes of operation, discontinuous current mode of operation(DCM), and continuous current mode of operation(CCM). A Digital Signal Processor(DSP) based implementation is carried out for validation of the Zeta converter developed design in discontinuous mode of operation. A comparison of both modes of operation is presented for a 1kW power rating from the point of view of steady state and dynamic behavior, power quality, simplicity, control technique, device rating, and converter size. The experimental results of a developed prototype of Zeta converter are presented for validation of the developed design. It is observed that CCM is most suitable for higher power applications where it requires some complex control and sensing of the additional variables.

• 한국군사과학기술학회지
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• 제16권4호
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• pp.566-574
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• 2013

In this paper, direct power control system for three-phase PFC AC/DC converter without the source voltage sensors is proposed. The sinusoidal input current and unity effective power factor are realised based on the estimated flux in the observer. Both active and reactive power calculated using estimated flux. The estimation of flux is performed based on the reduced-order virtual flux observer using the actual currents and the command control voltage. Moreover, source voltage sensors are replaced by a estimated flux. DC output voltage has been compensated by DC output ripple voltage estimation algorithm. The active and reactive powers estimation are performed based on the estimated flux and Phase angle. The proposed algorithm is verified through simulation and experiment.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.961_962
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• 2009

A novel, two-inductor, interleaved power-factor-corrected (PFC) boost converter that exhibits voltage-doubler characteristic when it operates with a duty cycle greater than 0.5 is introduced. The voltage-doubler characteristic of the proposed converter makes it quite suitable for universal-line (90~265VRMS) PFC applications. Because the proposed PFC boost rectifier operates as a voltage doubler at low line, its low-line range efficiency is greatly improved compared to that of its conventional counterpart. The performance of the proposed PFC rectifier was evaluated on an experimental 300W PFC prototype.

• 전력전자학회논문지
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• 제16권3호
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• pp.293-301
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• 2011

본 논문에서는 정류용 브릿지 다이오드가 없는 고효율 하프 브릿지 AC-DC 컨버터를 제안한다. 제안하는 컨버터는 비대칭 펄스 폭 변조 방식의 하프 브릿지 DC-DC 컨버터와 정류용 브릿지 다이오드가 없는 역률 개선 회로가 통합된 회로 구조를 지닌다. 제안하는 컨버터는 정류용 브릿지 다이오드를 사용하지 않고 교류 입력 전압으로부터 절연된 직류 출력 전압을 공급한다. 간단한 회로 구조와 함께 도통 손실을 줄일 수 있다. 또한 스위칭 소자들의 영전압 스위칭을 통하여 스위칭 손실을 줄일 수 있다. 두 개의 직렬 연결된 트랜스포머를 구비함으로서 프로파일을 낮추고 전력밀도를 높일 수 있다. 250 W (48 V / 5.2 A) 회로 설계 및 실험을 통하여 제안된 컨버터의 성능을 $90 \;V_{rms}$ 교류 입력 전압에 대하여 입증하였다.

• 전력전자학회논문지
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• 제15권6호
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• pp.460-465
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• 2010

최근 화석 연료의 고갈과 이산화탄소 배출 제한으로 인하여 내연기관 자동차에서 전기 자동차로의 대한 관심이 높아지고 있다. 전기 자동차 에너지 저장 요소인 배터리 충전에 필요한 AC-DC 컨버터가 필요하며 컨버터의 필요조건 으로 넓은 출력 전압 범위, 고효율, 높은 역률 등을 들수 있다. 넓은 전압 범위와 절연을 위해 2단 구성 하였다. 앞단은 LLC 컨버터를 후단은 역률을 고려 하여 BOOST 컨버터를 이용한 PFC 회로를 구현하여 실험적으로 확인 하였다.