• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.519-520
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• 2008

In this paper, we design and implement the monolithic zero crossing detection power factor correction IC using a high voltage 30V BCD process. The ZCD PFC IC is designed for power applications, such as notebook, LCD monitor, etc. It includes power factor correction function and several protection circuit, regulator, high-voltage high current output drivers. And also, the designed IC has restart timer function which the output pulse is generated if the output signal of IC is not in a 200us. The simulation results show that the designed IC acts properly as power factor correction IC with efficient protective functions.

• Proceedings of the KIPE Conference
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• 2003.11a
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• pp.90-94
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• 2003

Recently, many nations have released standard such as IEC 1000-3-2 and IEEE 519 which impose a limit on the harmonic current drawn by equipment connected to AC line in order to prevent the distortion of an AC line. Among the wide variety of active methods for improving power factor and harmonic distortion, the boost converter is very effective because it has a continuous line current , small choke filter and high power factor. In high power application, however, the bridge diode loss in the boost converter has made the efficiency lower and the temperature of the board higher. A new approach without bridge diode to make the same characteristics of the conventional boost converter has also been developed. This paper present the comparisons between the continuous current mode(CCM) operated conventional boost converter and the boundary current mode(BCM) operated the bridgeless boost converter for high efficiency and high power factor.

• Proceedings of the KIPE Conference
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• 1998.07a
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• pp.428-432
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• 1998

A passive energy recovery snubber for high-power-factor boost rectifier, in which the main switch is implemented with a MOSFET, is described in terms of the equivalent circuits that are operational during turn-on and turn-off sequences. The main switch combined with proposed snubber can be turned on with zero current and turned off at limited voltage stress. The high-power-factor boost rectifier with proposed snubber is implemented, and the experimental results are presented to confirm the validity of proposed snubber.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.28 no.1
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• pp.16-28
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• 2014

This paper presents a novel high-power-factor circuit topology of AC to AC current-fed type high frequency resonant inverter which includes the function of power factor correction(PFC) in the proposed inverter to operate the AC input block with high power factor. The proposed circuit topology of AC to AC current fed type high resonant inverter removes DC link electrolytic capacitor and has also the one of power factor correction(PFC) in the inverter circuit without an additional PFC circuit since the input current by constituting it in parallel as an unit inverter, which assumes the class-E high frequency resonant inverter of conventional current-fed type, flows in the form of the resultant current flowing through each constant current reactor($L_{d1}$, $L_{d2}$). The circuit analysis of proposed inverter is generally described by adopting the normalized parameters and the evaluation of its operating characteristics are conducted by using the parameters such as the ratio of switching and resonant frequency(${\mu}$), coupling coefficient(k) and so on. An example of procedure for circuit design based on the characteristic values obtained from the theoretical analysis is presented. To confirm the validity of the theoretical analysis, the experimental results are also presented. In the future, the proposed inverter shows it can be practically used as power supply system for induction heating application, DC-DC converter etc.

• Proceedings of the KIEE Conference
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• 1997.07f
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• pp.2072-2074
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• 1997

A new low-cost high power factor correction circuit for electronic ballasts is proposed. The proposed circuit provides good power factor correction, low current harmonic distortion and cost-effectiveness. The prototype meets the IEC555-2 requirements satisfactorily with nearly unity power factor.

• Journal of the Earthquake Engineering Society of Korea
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• v.24 no.3
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• pp.123-128
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• 2020

Analysis of the 2016 Gyeongju earthquake and the 2017 Pohang earthquake showed the characteristics of a typical high-frequency earthquake with many high-frequency components, short time strong motion duration, and large peak ground acceleration relative to the magnitude of the earthquake. Domestic nuclear power plants were designed and evaluated based on NRC's Regulatory Guide 1.60 design response spectrum, which had a great deal of energy in the low-frequency range. Therefore, nuclear power plants should carry out seismic verification and seismic performance evaluation of systems, structures, and components by reflecting the domestic characteristics of earthquakes. In this study, high-frequency amplification factors that can be used for seismic verification and seismic performance evaluation of nuclear power plant systems, structures, and equipment were analyzed. In order to analyze the high-frequency amplification factor, five sets of seismic time history were generated, which were matched with the uniform hazard response spectrum to reflect the characteristics of domestic earthquake motion. The nuclear power plant was subjected to seismic analysis for the construction of the Korean standard nuclear power plant, OPR1000, which is a reactor building, an auxiliary building assembly, a component cooling water heat exchanger building, and an essential service water building. Based on the results of the seismic analysis, a high-frequency amplification factor was derived upon the calculation of the floor response spectrum of the important locations of nuclear power plants. The high-frequency amplification factor can be effectively used for the seismic verification and seismic performance evaluation of electric equipment which are sensitive to high-frequency earthquakes.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.19 no.8
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• pp.102-108
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• 2005

In this paper, authors propose novel boost AC-DC converter of high power factor and analyze for waveform and harmonics component of input current. The input current waveform in the proposed converter is got to be a sinusoidal form of discontinuous pulse in proportion to magnitude of at input voltage under the constant duty cycle switching. Therefore, input power factor is nearly unity. Particularly, the stored energy of loss-less snubber capacitor is recovered with input side and increases input current from resonant operation. The result is that input power factor of the proposed converter is higher than that of conventional converter of high power factor. Some simulative results on computer and experimental results are included to confirm the validity of the analytical results.

• Proceedings of the KIEE Conference
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• 2003.10b
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• pp.187-189
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• 2003

Conventional Switched Mode Power Supplies(SMPS) with diode-capacitor rectifier have distorted input current waveform with high harmonic content. Typically, these SMPS have a power factor lower than 0,65. To improve with this problem the power factor correction(PFC) circuit of power supplies has to be introduced. Specially. to the reduce size and manufacture cost of power conversion device, the single-stage PFC converter is increased to demand as necessary of study. in this paper, The comparative analysis of power factor correction circuit using Feedforward control with average current mode flyback converter(single-stage) and boost converter(two-stage). Also, the validity of designed and manufactured high power factor flyback converter and boost converter is confirmed by simulation and experimental results.

• 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.

• Journal of IKEEE
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• v.22 no.3
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• pp.767-773
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• 2018

This paper proposes the simple structure LED-driving power converter with high power factor. As the proposed power converter combines the PFC boost converter and the conventional flyback converter into only one power conversion circuit, it simplifies the structure of LED-driving power converter. Thus the proposed converter is controlled using only one PWM controller IC, and it achieves high power factor, constant output voltage/current and cost-effectiveness. Therefore the proposed converter is suitable for the industry production and utilization of LED-light-system. In this paper, the operation analysis and design example of the proposed converter are explained, briefly. Also experimental results of the prototype that is implemented based on the designed circuit parameters are shown to validate operation characteristics of the proposed converter.