• Title/Summary/Keyword: PFC

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Various Algorithms of Service Recovery in IP Network (IP 네트워크 상의 다양한 서비스 복구 알고리즘)

  • Han Jeong Soo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.10B
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    • pp.841-848
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    • 2004
  • In case of failure in the IP network services should be provided via a backup path which fully meets QoS requirements. In this regard, we in this paper suggest simple-PFC(5-PFC) to restore single link failure, iterative-PFC(i-PFC) for multiple link failures, and fault_node Avoidance-PFC(a-PFC) for failures of nodes such as routers. Taking the minimum cost rerouting problem into account, we compare and analyze performance of those three mechanisms carrying out Direct_destination Rerouting(DR).

Various Algorithms of Service Recovery in IP Network (IP 네트워크 상의 다양한 서비스 복구 알고리즘)

  • Han, Jeong-Soo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.9B
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    • pp.791-798
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    • 2004
  • In case of failure in the IP network, services should be provided via a backup path which fully meets QoS requirements. In this regard, we in this paper suggest simple-PFC(s-PFC) to restore single link failure, iterative-PFC(i-PFC) for multiple link failures, and fault_node Avoidance-PFC(a-PFC) for failures of nodes such as routers. Taking the minimum cost rerouting problem into account, we compare and analyze performance of those three mechanisms carrying out Direct-destination Rerouting(DR).

Analysis of the Electronic Ballast with Semi-boost PFC for Fluorescent Lamps (Semi-boost PFC에 의한 형광등용 전자식 안정기 해석)

  • Han, Jae-Hyun;Jo, Gye-Huyn;Park, Chong-Yeun
    • Journal of Industrial Technology
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    • v.23 no.A
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    • pp.35-39
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    • 2003
  • There are many kinds of electronic ballast for various kinks of fluorescent lamps. The PFC(Power Factor Correction) circuit in electronic ballast is classified in two types. One is the active PFC and the other is the passive PFC circuit. The active type PFC is higher than the passive type, but the cost of the passive type is cheaper than the active type. In this study, we introduced the modified passive PFC method which is called semi-boost PFC, and then we analyzed and experimented the electronic ballast which is composed of the semi-boost PFC, half-bridge, and LCC resonant tank. Experimental results showed that the $$PF{\geq_-}0.98$$, $$CF{\leq_-}1.4$$ and input current $THD{\approx}15%$.

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A Continuous Conduction mode/Critical Conduction Mode Active Power Factor Correction Circuit with Input Voltage Sensor-less Control (입력전압을 감지하지 않는 전류연속/임계동작모드 Active Power Factor Correction Circuit)

  • Roh, Yong-Seong;Yoo, Changsik
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.8
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    • pp.151-161
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    • 2013
  • An active power factor correction (PFC) circuit is presented which employs a newly proposed input voltage sensor-less control technique operated in continuous conduction mode (CCM) and critical conduction mode (CRM). The conventional PFC circuit with input voltage sensor-less control technique degrades the power factor (PF) under the light load condition due to DCM operation. In the proposed PFC circuit, the switching frequency is basically 70KHz in CCM operation. In light load condition, however, the PFC circuit operates in CRM and the switching frequency is increased up to 200KHz. So CCM/CRM operation of the PFC circuit alleviates the decreasing of the PF in light load condition. The proposed PFC controller IC has been implemented in a $0.35{\mu}m$ BCDMOS process and a 240W PFC prototype is built. Experimental results shows the PF of the proposed PFC circuit is improved up to 10% from the one employing the conventional CCM/DCM dual mode control technique. Also, the PF is improved up to 4% in the light load condition of the IEC 61000-3-2 Class D specifications.

A Design of PFC Circuit for Reducing the Harmonic in Constant Voltage-fed Electronic Ballast Circuit (정전압형 전자식 안정기 회로의 고조파 저감을 위한 PFC회로의 설계)

  • 이현우;이현무;고강훈;고희석
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.18 no.4
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    • pp.41-48
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    • 2004
  • In this paper, a PFC(Power Factor Correction) electronic ballast with constant voltage-fed is proposed. The proposed PFC electronic ballast is combined of a high-efficiency boost converter and a conventional half bridge inverter. It is proved that the ripple of input-current and the input-current's harmonic of the proposed PFC electronic ballast are reduced using the voltage divider and soft-switching technique. It is demonstrated that simulation results for fluorescent lamp correspond with theoretical analysis.

The Digital Controller of the Single-Phas Power Factor Correction(PFC) having the Variable Gain (가변 이득을 가지는 단상 PFC 디지털 제어기)

  • 정창용
    • Proceedings of the KIPE Conference
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    • 2000.07a
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    • pp.163-167
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    • 2000
  • This paper presents the digital control of single-phase power factor correction(PFC) converter which has the variable gain according to the condition of inner control loop error. Generally the gain of inner current control loop in single-stage PFC converter has a constant magnitude. This has a bad influence on the power factor because current loop doesn't operate smoothly in the condition that input voltage is low In particular a digital controller has more time delay than an analog controller and degrades This drops the phase margin of the total digital PFC system,. It causes the problem that the gain of current control loop isn't increased enough. In addition the oscillation happens in the peak value of the input voltage open loop PFC system gain changes according to ac input voltage. These aspects make the design of the digital PFC controller difficult The digital PFC controller presented in this paper has a variable gain of current control loop according to input voltage. The 1kW converter was used to verify the efficiency of the digital PFC controller.

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Loss Analysis of High Efficiency PFC Circuit Using PSIM (PSIM을 이용한 고효율 역률개선회로의 손실분석)

  • Sung, Won-Yong;Kim, Yun-Sung;Cho, Nam-Jin;Lee, Byoung-Kuk
    • Proceedings of the KIPE Conference
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    • 2012.11a
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    • pp.151-152
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    • 2012
  • 본 논문은 전기자동차의 탑재형 충전기 (OBC, On-Board Charger)에 적용 가능한 고효율 역률개선회로 (PFC, Power Factor Correction Circuit)들의 손실을 분석한다. 평균전류모드제어를 이용하여 conventional boost PFC, interleaved boost PFC, semi-bridgeless PFC, totem pole PFC, seudo totem pole PFC, back-to-back bridgeless PFC, interleaved bridgeless PFC 등 7개의 토폴로지를 3.3kW OBC 기반으로 설계하고, 각 토폴로지의 손실을 수식과 PSIM의 thermal module을 이용하여 분석한다. 분석한 결과를 토대로 제시한 토폴로지들의 효율 및 성능을 비교한다.

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Conducted Noise Reduction in PFC Boost Converter for Air Conditioner (에어컨용 PFC Boost Convertor의 전도 노이즈 저감)

  • 이성희;김이훈;김영규;원충연;김태덕;김대경
    • The Transactions of the Korean Institute of Power Electronics
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    • v.8 no.5
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    • pp.455-462
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    • 2003
  • Switching PFC converters are widely used not only to comply the power quality specification but also for maximum efficiency. However switching PFC converters generate serious electromagnetic interference(EMI). In this paper to solve this problem, we applied the APW(Anti-Phase Winding) and RPWM(Random PWM) technique to PFC boost converter and obtained good results. Simulation and experimental results show the improved harmonics and reduced EMI effect in air-conditioner system.

A Study on the PFC-Inverter with the ZVT-Switching Method (ZVT 스위칭 기법을 적용한 PFC-인버터)

  • 이성룡;전칠환;권순신
    • The Transactions of the Korean Institute of Power Electronics
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    • v.5 no.6
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    • pp.560-567
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    • 2000
  • A soft-switching PFC-Inverter for using AC motor drive such as the inverter air-conditioner with single phase medium size is proposed. In order to improve the power factor and the efficiency, in this paper, the ZVT topoloty in the conventional PFC-Inverter is adopted. So, the operation mode of the proposed ZVT PFC-Inverter is analyzed and the optimum circuit is designed. At last, the PSPICE, PSIM simulation and experiment results are presented in order to verify the validity of the proposed circuit.

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A Digital Control of Interleaved PFC for 3-Phase Modular UPS (3상 모듈형 UPS용 Interleaved PFC의 디지털 제어)

  • Kim, Sang-Hoon;Park, Nae-Chun
    • Journal of Industrial Technology
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    • v.32 no.A
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    • pp.39-45
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    • 2012
  • In this paper the digital control scheme of interleaved PFC for 3-phase modular UPS is presented. The interleaved PFC is composed of two identical PFC connected in parallel and each PFC is controlled by the interleaved switching signals which have the same switching frequency and the $180^{\circ}$ phase difference. As a consequence of the interleaving operation, the Interleaved PFC exhibits both lower current ripple at the input side and lower voltage ripple at the outside. Therefore, the switching and conduction losses as well as EMI levels can be significantly decreased. Simulation and experimental results verify the usefulness of the interleaved PFC.

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