• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2001년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
• /
• pp.233-235
• /
• 2001

On the active filter converter for power factor correction is used inverter for a air-conditioner's power supply to meet IEC standard In the active filter topology for power factor correction, extra switch only control the input current indirectly to satisfied with the IEC standard for reducing the cost and size. In this paper, by dividing the input current into two different modes, the current conduction period can be widened and harmonics can largely be canceled between the two modes. Hence, the harmonics characteristics can be significantly improved, whereby the lower order harmonics, such as the fifth and seventh orders, are much reduced. The results are confirmed by theoretical and experimental implementations.

• 한국조명전기설비학회:학술대회논문집
• /
• 한국조명전기설비학회 2004년도 춘계학술대회 논문집
• /
• pp.34-39
• /
• 2004

Fluorescent lamp operated at high frequency by the electronic ballast provide ballasts like unnoticed flicker effect and higher luminous efficiency. This paper presents analysis of Half-Bridge type resonant inverter for Fluorescent lamp drive for stable characteristic and life improvement of lamp operated at high frequency. Also, it has described an electronic ballast design with the capability of high PF (Power Factor) and low THD (Total Harmonic Distortion). The validity of designed electronic ballast circuit is confirmed by simulation and experimental results. The Designed electronic ballast is implemented successfully on 32W Fluorescent lamp system.

• 조명전기설비학회논문지
• /
• 제25권8호
• /
• pp.20-29
• /
• 2011

This paper presents an improved phase-shift pulse-width modulation (PWM) full-bridge converter using a blocking capacitor. As the proposed converter reduces the circulation energy by inserting only one series blocking capacitor at the primary side of the conventional phase-shift PWM full-bridge converter structure, it improves the operation characteristics of the conventional converter. In this paper, first, the operation of conventional phase-shift PWM full-bridge converter is roughly reviewed, and then the operational principle of the proposed converter is classified and explained by each mode. After that, a prototype design example based on the operational principle is shown. Then, the improved operation characteristics of the proposed converter are actually verified through the experimental results.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2007년도 하계학술대회 논문집
• /
• pp.359-361
• /
• 2007

본 논문은 CNT(Carbon Nano Tube) FEL(Field Emission Lamp)에서 애노드(Anode)-캐소드(Cathode) 구동용 고전압 구동 회로 구현에 관한 것이다. 본 논문에서 제안하는 고전압 DC 전원 회로는 턴비가 높은 고전압 트랜스포머의 Leakage 인덕턴스를 이용하는 Series-Resonant 형태의 Full Bridge 컨버터를 적용하고 고전압 트랜스포머와 Voltage Multiplier를 이용한다. 고전압 트랜스의 절연전압을 줄이기 위해서 두개의 트랜스포머와 Voltage Multiplier를 이용하여 애노드 전극에는 Positive 고전압, 캐소드 전극에는 Negative 고전압을 인가한다. 이 경우 애노드와 캐소드 사이의 아크 방전 시에도 구동 IC 및 스위칭 소자를 보호할 수 있는 장점이 있다.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2017년도 전력전자학술대회
• /
• pp.421-422
• /
• 2017

The kicker modulator was upgraded and installed in 1995. The PLS-II injection kicker modulator is configured with series resonant circuit. A total of four kicker magnets are used to distribute the normal storage ring beam orbit toward the septum magnet wall. Only one kicker modulator is used to drive the four kicker magnets. It is not adjust the current magnitude and timing of magnets. During the kicking, the beam has oscillation of 2 mm horizontal direction and $200{\mu}m$ vertical direction in present injector system. Our goals is to decrease the oscillation less than $300{\mu}m$. To give balanced current for all four magnets and to have precise timing between magnet current, we have plan to divide kicker power supply into four individual power supply. In this paper, the design of new individual kicker power supply and Fabrication of the new injector system is presented.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2017년도 전력전자학술대회
• /
• pp.264-265
• /
• 2017

본 논문에서는 3상 220V/5kVA 소프트스위칭 인버터의 새로운 회로구성을 제안하고 그 동작과 성능을 분석한 내용을 기술하고 있다. 제안하는 소프트스위칭 인버터는 ARCP(Auxiliary Resonant Commutated Pole) 인버터의 회로구성과 유사한 구조이나 이와 달리 LC 공진회로와 Diode 클램프 회로로 구성되어 있다. 이론적인 분석과 실험을 통해 제안하는 인버터의 효율을 분석하고 이를 하드스위칭 인버터와 비교하여 약 1% 정도의 효율 개선이 가능함을 알 수 있었다. 제안하는 인버터는 소프트 스위칭을 위해 소프트스위칭 보조회로와 게이트 드라이버가 추가로 장착되는 점에서 비용적인 경쟁력이 떨어질 수 있다. 그러나 최근 수요가 급증하고 있는 인버터에서 1% 효율 차이는 전력수급의 효율화를 통해 비용 측면에서 경쟁력을 갖을 것으로 판단된다. 또한 소프트스위칭 회로의 컴팩트화와 하드웨어의 최적화된 물리적 배치를 통해 추가의 효율증대가 가능할 것으로 보인다.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2003년도 하계학술대회 논문집 B
• /
• pp.1235-1237
• /
• 2003

For small capacity rectifier circuits as these for consumer electronics and appli capacitor input type rectifier circuits are gen used. Consequently. various harmonics gen within the power system become a serious pro Various studies of this effect have been pres previously. However. most of these employ swit devices, such as FETs and the like. The absen switching devices makes systems more toleran over -load, and brings low radio noise benefits propose a power factor correction scheme using resonant in commercial frequency without swit devices. In this method. It makes a sinusoidal by widening conduction period using the cu resonance in commercial frequency. Hence, harmonic characteristics can be significantly imp where the lower order harmonics. such as the and seventh orders are much reduced. The resu confirmed by the theoretical and experm implementations.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1993년도 하계학술대회 논문집 A
• /
• pp.287-289
• /
• 1993

Recently semiconductor technology is widely used in biotechnology fields and one of the represetatives is electric cell-fusion-device. In this paper. some basic researches required in the development of this fusion system was performed and they are as follows: 1) preparation of protoplast and selection of the fittest plant cell, 2) development of high frequency AC power supply for cell-alignment by using class-E resonant circuit. As a result, cabbage cell is selected and pearl-chain, which shows cell-alignment. can be observed by the applied AC field.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2009년도 춘계학술대회 논문집 에너지변화시스템부문
• /
• pp.156-160
• /
• 2009

This paper presents the interleaved active-clamping ZVS(Zero Voltage Switching) forward converter, which is mainly composed of two active-clamping forward converters. Only two switches are required, and each one is the auxiliary switch for the other. The circuit complexity and cost are thus reduced. The leakage inductance of the transformer or an additional resonant inductance is employed to achieve ZVS during the dead times. The duty cycles are not limited to be equal and within 50%. The complementary switching and the resulted interleaved output inductor currents diminish the current ripple in output capacitors. Accordingly, the smaller output chokes and capacitors lower the converter volume and increase the power density. Detailed analysis and design of this new interleaved active-clamping forward converter are described.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2001년도 전력전자학술대회 논문집
• /
• pp.589-593
• /
• 2001

This paper presents a high frequency modulation electronic ballast for the metal halide lamp. As the proposed ballast operates in high frequency ranges (20kHz - 100kHz) and it can start up the lamp using the LC resonant circuit without external igniter, the proposed ballast is very compact. The proposed ballast is controlled with the modulated frequency in the range of 20kHz to 100kHz, and it has variable modulating frequencies between 200Hz and 2kHz in order to avoid the acoustic resonance phenomenon. In this paper, a new realtime acoustic resonance detection method is described and the experimental results with the proto-type ballast of 150W metal halide lamp with the dimming function are discussed.