• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 B
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• pp.1129-1131
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• 2001

A new low cost single stage high power factor electronic ballast for fluorescent lamps is presented in this paper. The proposed topology is based on integration of two-boost converter and LC type high frequency resonant converter. A ballast is obtained by simple construction, because full bridge rectifier diode is eliminated and simple control circuits is applied. Using two boost converter operating positive and negative half cycle respectively at line frequency (60Hz), operating in discontinuous conduction mode performs high power factor. The simulated and experimental results for 64W fluorescent lamps operating at 45kHz switching frequency and 110V line voltage have been obtained.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 추계학술대회 논문집 전력기술부문
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• pp.277-279
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• 2005

Generally, It was used to use a unit of a Large regularity in developing Large Capacity Converter System of the electric power. Lager a capacity of a unit of regularity, more expensive cost of it. So, normally, We overcome the limit of a proper form of an electricity semiconductor which be used in application field of Large capacity electricity conversion system through the Composition of Multi-level Circuit or Dual-Mode or parallel switch. but some problem is discussed. Using parallel RC-diode circuit instead of Large Capacity diode, We implemented a circuit that it overcome the limit of a regularity with dealing current distributed by parallel RC-diode circuit.

• 전력전자학회논문지
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• 제20권1호
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• pp.59-64
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• 2015

This paper proposes an analysis and operation strategy of a grid-connected wind turbine system using a diode rectifier. The currents of generators are the same as that of a small wind turbine system. Therefore, the analysis of generator torque is required as opposed to an analysis of blade speed. In this paper, the appropriate MPPT control method is proposed to control generator torque. Usefulness of the proposed operation strategy is verified by simulations and experiments.

• 전기의세계
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• 제24권1호
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• pp.43-53
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• 1975

This paper describes a converter, which combines SCR bridge type rectifier circuit with a rotating distributor. This type of converter produces an adjustable low frequency output of three phase or single phase, from three phase or single phase power source. Output-waveforms of this converter are multi-pulse in three phase output, and square wave in single phase output. Problems about the operation of static switches, a commutation and output-waveforms are investigated, and experimental results verify that frequency can be adjusted satisfactorily from zero to 20 (Hz) and the expected output-waveforms are obtained without sparking on the distributor under various loading conditions. This converter can be utilized to low speed control of A.C. motors, and other lowfrequency loads.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제49권9호
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• pp.590-597
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• 2000

Design of single state AC-DC converter with high power factor for low level applications is proposed. The proposed converter is obtained from the integration of a buck-boost converter and the half-bridge DC-DC converter. This converter gives the good power factor correction low line current harmonic distortions and tight output voltage regulations. This converter also has a high efficiency by employing an soft switching method and synchronous rectifier. The modelling and detailed analysis for the proposed converter are performed. To verify the performance of the proposed converter a 100W converter has been designed

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 추계학술대회 논문집
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• pp.289-292
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• 2007

The modular line-connected photovoltaic PCS (power conditioning system) is proposed. The proposed system consists of a step-up DC-DC converter and a full-bridge inverter. A step-up DC-DC converter using a dual series-resonant rectifier circuit and a active-clamp circuit is proposed to achieve a high efficiency and a high input-output voltage ratio efficiently. An IncCond (incremental conductance) MPPT (maximum power point tracking) algorithm that improves MPPT characteristic is used. By control a inverter using a linearized output current controller, a unity power factor is achieved. All algorithms and controllers are implemented on a single-chip microcontroller and the superiority of the proposed algorithms and controllers is proved by experiments.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2015년도 제46회 하계학술대회
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• pp.1010-1011
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• 2015

최근 고효율 전력변환을 위해 LLC 공진형 하프브릿지 컨버터의 동기정류기에 대한 연구가 활발히 진행되고 있다. 기존 일반적인 다이오드 정류기를 사용하는 경우 출력전류에 비례하는 전력손실이 커서 대전력용으로 사용하기에는 적합하지 않다. 따라서 스위치를 이용한 동기정류기가 검토되고 있는데 동기정류기의 스위치를 구동시키기 위해서는 스위치를 구동시킬 수 있는 구동용 IC가 이용되고 있다. 동기정류기 구동 IC의 단점으로는 약 50%의 중부하 이하에서는 동작되지 않는 단점이 있어 이를 보완하기 위하여 변압기 1차측 전류를 검출하여 게이트 전압을 만들어 스위치를 구동시키는 회로를 제안하였다. 본 논문의 실험 결과 저전력 지점에서 동기정류기가 구동되었고 따라서 전력변환 효율은 기존의 다이오드 정류기에 비해 우수하며 효율개선효과가 있다는 것을 실험으로 보였다.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 1999년도 학술대회논문집-국제 전기방전 및 플라즈마 심포지엄 Proceedings of 1999 KIIEE Annual Conference-International Symposium of Electrical Discharge and Plasma
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• pp.273-278
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• 1999

This paper presents a novel Power Factor Corrected(PFC) single-stage AC/DC Half-Bridge converter, which features discontinuous conduction mode(DCM) and soft-switching. The reduced conduction losses are achieved by the employment of a novel power factor correction circuitry, instead of the conventional configuration composed of a front-end rectifier followed by a boost converter. To identify the validity of the proposed converter, simulated results of 500[W] converter with 100[V] input voltage and 50[V] output voltage are presented.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2000년도 춘계학술대회논문집 - 한국공작기계학회
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• pp.385-390
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• 2000

This paper deals with the design and simulation of the hybrid power filter to compensate reactive power and harmonic components of nonlinear load. Control target is a 3-phase diode full bridge rectifier with L-R-C nonlinear load, this load is assumed adjustable speed driver(ASD). The hybrid filter consists of a shunt active filter, shunt passive filters and series inductors. Control algorithm is based on instantaneous power compensation theory proposed by H.Akagi and etc. The result from simulation shows the hybrid filter is superior than other filters on the point of compensation performance and low cost. The PSCAD/EMTDC 3.0 is used as simulation tools.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2002년도 전력전자학술대회 논문집
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• pp.589-592
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• 2002

The CCM (Continuous Conduction Mode) boost topology is generally used in the PFC (Power Factor Correction) regulator of household air-conditioning systems. There are three kinds of power devices-bridge rectifier diodes, FRDs (Fast Recovery Diodes), and IGBTs (or MOSFETs) - used In a boost PFC regulator. Selecting the appropriate device is very cumbersome work, specially, in the case of FRDs and IGBTs, because there are several considerations as described below: 1) High frequency leakage current regulation (conducted and radiated EMI regulation) 2) Power losses and thermal design 3) Device cost. It should be noted that there are trade-offs between the power loss characteristic of 2) and the other characteristics of 1) and 3). This paper presents a detailed evaluation by using several types of power devices, which can be unintentionally used, to show that optimal selection can be achieved. Based on the given thermal resistances, thermal analysis and design procedures are also described from a practical viewpoint.