• Title/Summary/Keyword: 역률

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Integrated Boost-Flyback ZCS Quasi-Resonant Power Factor Preregulator (부스트-플라이백 결합형 ZCS Quasi-Resonant 역률개선 컨버터)

  • 이준영;문건우;김현수;윤명중
    • The Transactions of the Korean Institute of Power Electronics
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    • v.4 no.1
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    • pp.91-98
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    • 1999
  • An integrated ZCS quasi-resonant converter(QRC) for the power factor correction with a single switch is presented in this paper. The power factor correction can be achieved by the discontinuous conduction mode(DCM) operation of the input current. The proposed converter gives the good power factor, low line current harmonics, and tight output regulation. The input current waveform of the prototype designed using design equations shows about 15% of total harmonic distortion at rated condition. Also, the efficiency and power factor can be obtained about 86% and 0.985, respectively, at rated condition. The proposed converter is suitable for a low power level converter with a tightly regulated low output voltage and switching frequency of more than several hundreds kHz.

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A Study of Stability Analysis for Exit Light (유도등의 안정성 해석에 관한 연구)

  • Jung, Jong-Jin;SaKong, Seong-Ho
    • Journal of the Korean Society of Hazard Mitigation
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    • v.8 no.4
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    • pp.81-85
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    • 2008
  • In this study, Standards of Lighting Appliance and Standard of Model Approval and Inspection Technology for EXIT LIGHT are compared so as to analyze stability of a exit light which is fire product. Test items, which are not included in Standard of Model approval and Inspection Technology for EXIT LIGHT, are deduced from aforementioned comparison and analysis. Also the derived test items are experimented with a exit light. For a power factor correction, a power factor correction circuit is designed and power factor, crest factor, asymmetry ratio, luminance variation are analyzed. In order to show the validity of designed circuit, current waveform and voltage waveform are measured.

A Single-Stage Power Factor Correction Converter far $90-265V_{rms}$ Line Applications ($90-265V_{rms}$ 입력범위를 갖는 단일전력단 역률개선 컨버터)

  • 이준영;박희정;구관본;윤명중
    • The Transactions of the Korean Institute of Power Electronics
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    • v.5 no.5
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    • pp.508-514
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    • 2000
  • A single-stage power factor correction AC/DC converter with a simple link voltage suppressing circuit (LVSC) for the universal line application is proposed. Using this simple circuit, a low link voltage can be realized without deadbands at line zero-crossings. The proposed converter is analyzed and a prototype converter with 5V, 12A output is implemented to verify the performance. The experimental results show that the link voltage stress and efficiency are about 447V and 81%, respectively.

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The Design and Experiment of Power Factor Improvement Circuit for a Underwater Electro Acoustic Transducer with Low Coupled Dual Resonances (상호 결합이 적은 두 개의 공진점을 갖는 수중용 광대역 전기 음향 변화기를 위한 역률 개선 회로 설계 및 실험)

  • Lim, Jun-Seok;Pyeon, Yong-Guk
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38B no.12
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    • pp.967-975
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    • 2013
  • In the design of underwater electro acoustic transducer, power factor improvement circuit is more required rather than impedance matching if the driving power amplifier has little inner resistance. Many research results have been focused on the power matching circuit designing for transferring maximum power in the wideband. There are few results in the designing study on the power factor improvement for the wide band underwater electro acoustic transducer. In this paper, we set up a new design method on the power factor improvement for the wide band electro acoustic transducer, and confirm its feasibility by the experiments.

A Research of Power Factor Improvement using Phase Control of Active Harmonic Filter (고조파저감설비 위상제어를 통한 역률 향상에 관한 연구)

  • Choi, Won-kyu;Lee, Hwan;Jung, No-Geon;Jeon, Yeon-Ju;Kwon, Kyoung-min;Kim, Jae-Moon
    • Proceedings of the KIEE Conference
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    • 2015.07a
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    • pp.1609-1610
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    • 2015
  • 국내 철도 변전소의 부하전력은 부하인 철도차량의 부하특성에 의해 고조파와 역률이 매우 좋지 못한 실정이다. 이러한 이유에서 철도변전소에는 고조파를 보상하기위한 고조파 저감설비와 역률을 개선시키기 위한 역률보상용 콘덴서와 같은 전력품질개선설비(FACTs) 들이 설치되고 있다. 본 논문에서는 이러한 철도차량 부하의 차량별 고조파 특성을 살펴보고, 이를 효과적으로 제어할 수 있는 방법을 제안하였다. 제안된 알고리즘은 고조파저감설비의 위상제어를 통한 역률 향상을 도모하기 위한 것으로 일반적인 밴드패스 필터를 사용한 고조파 전류성분 검출에 따른 제어방식과 달리 고조파 전류에 대한 Lyapunov 안정도에 기반을 둔 제어방식을 적용하여 빠른 전류제어 동특성을 같도록 제안하였고 시뮬레이션과 실 부하 계통에 설치하여 운용함으로 그 타당성을 입증하였다.

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A novel PFC AC/DC converter for reducing conduction losses (도통손실 저감형 역률 보상 AC/DC 컨버터)

  • Kang, Feel-Soon;Choi, Cheul;Park, Sung-Jun;Kim, Cheul-U
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.14 no.2
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    • pp.52-58
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    • 2000
  • 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 powder 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.

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Design of Active Power Factor Corrector for Low Power Supply by Loss Free Resistor Concept (무손실 저항개념을 이용한 저전력 전원설비용 능동 역률보정기의 설계)

  • 임영철;정영국;최찬학;나석환;이건식;장영학
    • The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.7 no.1
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    • pp.30-36
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    • 1993
  • A simple discontinuous conduction mode(DCM) flyback type active power factor corrector for low power supply resents an effective resistive load to its power input. It is therefore well suited as an inexpensive high power factor rectifier for office equipment. An equivalent circuit model for the Active Power Factor Corrector based on the "Loss Free Resistor" concept is presented. This simple model correctly describes the basic power processing properties of the Active Power Factor Corrector, including input port resistor emulation, output port power some characteristics.teristics.

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A Study on Simple Single phase Air-conditioner of Power factor Correction Circuit (심플한 단상 에어컨의 역률개선회로에 관한 연구)

  • 문상필;서기영;이현우;김영문;김영철
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.15 no.2
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    • pp.73-79
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    • 2001
  • This paper describes the simple single phase air-conditioner of power factor correction (PFC) circuit. By adopting PFC in the rectifier, we can reduce harmonic into power line, improve the efficiency and lower the total system cost compared to conventional inviter only. Also, system performance is improved by stabilizing the output voltage of PFC. To improve the current waveform of diode rectifiers, we propose a new operating principle for the voltage diode rectifiers. A circuit design method is shown by experimentation and confirmed simulation. It explained that compared conventional pulse-width modulated (PWM) inverter with half pulse-width modulated (HPWM) inverter HPWM inverter. Proposed HPWM inverter eliminated dead-time by lowering switching loss and holding over-shooting.

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A Study on the Power Factor Correction and Harmonics Reduction of Capacitor Banks installed at Customers (수용가에 설치된 캐패시터 뱅크의 역률개선 및 고조파 저감에 관한 연구)

  • Kim, Kyung-Chul;Choi, Hyoung-Bumb
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.22 no.8
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    • pp.12-17
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    • 2008
  • Most power system loads and delivery apparatus are inductive in nature and therefore operate at a lagging power factor. Applying capacitor banks to a customer will result in a power factor correction and other benefits such as VAR support, increased voltage, reduced power losses, and reduced billing charges. Also there can be power quality problems as a result of adding capacitor banks. The most common are harmonics. This paper provides an in depth analysis on the power factor correction and harmonics reduction of capacitor bank installed at a customer. The EDSA program was used as a simulation tool for the case study.

Single-Stage High Power Factor Converter for 90-260Vrms Input (90-260Vrms 입력 범위를 갖는 단일 전력단 고역률 컨버터)

  • 김학원;문건우;조관열;윤명중
    • The Transactions of the Korean Institute of Power Electronics
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    • v.7 no.1
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    • pp.18-29
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    • 2002
  • Generally, the single-stage power factor corrected converter has a problem of high dc link voltage. In the case of high line voltage, especially, the dc link voltage is verb high under the light load condition. To solve this problem, a new single stage power factor corrected AC/DC converter has been proposed. The proposed converter has huck topology as a power factor corrector. To prove feasibility of the proposed converter, the design example of the proposed converter has been presented. The design considerations and experimental results for the proposed converter have been shown. The experimental results show that the line input current harmonics can meet IEC1000-3-2 Class D requirements for the range of line input voltage from 90Vrms to 260Vrms.