• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.205-207
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• 2007

Isolated Current fed full-bridge converter with active clamp is analyzed in this paper. An active clamp branch is used for limiting the voltage overshoot in the bridge switches and rectifier diodes. Zero voltage switching(ZVS) is also realized by using the energy stored in the transformer leakage inductance. To analyze the converter, 6 modes of operation are introduced and investigated. For each of the modes, voltage and current equations are derived together with corresponding equivalent circuits. 200W prototype dc-dc converter is assembled and verifies the effectiveness of the analysis and simulation.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1992년도 춘계학술대회
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• pp.148-151
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• 1992

There is a definite requirement to continuously monitor the operating characteristics of radiation therapy machines. It is advisable to monitor the symmetry, flatness, and energy stability of x-ray beams. The semiconductor system was developed using commercially available rectifier diode for th assessment of quality assurance In radiation therapy, which is capable of the above measurements. The beam characteristics of 6MV, 10MV and 21MV photon of Microtron electron accelerator were measured using seven-diodes as detectors and the results were compared with that of using a film results dosimetry with a X-Y plotter. The seven-diode detetor is versatile enough to be used for checking beam profile, flatness, symmetry and energy.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2004년도 전력전자학술대회 논문집(2)
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• pp.601-605
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• 2004

A new high efficiency and low profile on-board DC/DC converter for digital car audio amplifier is proposed. The proposed converter shows the continuous input current, no DC excitation current of the transformer, the minimized electro-magnetic interference (EMI), no output inductor, and the low voltage stress of the secondary rectifier diodes. The 60W industrial sample of the proposed converter is implemented for digital car audio amplifier and the measured efficiency is $88.3\%$ at nominal input voltage.

• 전자공학회논문지SC
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• 제47권2호
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• pp.50-54
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• 2010

반감(半減)되는 특성을 가진 폴딩 스너버 망을 내포하므로 소프트하게 역 복귀 되는 새로운 형태의 의사 공진 펄스 폭 변조 컨버터를 소개한다. 이 컨버터는 이미 소개된 기존의 QRC에 단지 수동소자만으로 구성된 폴딩 스너버를 결합하여 구현시켰다. 이용된 수동소자는 단지 다이오드와 케페시터로 구성되었다. 이렇게 제안된 펄스 폭 변조 컨버터의 효율은 매우 높아 대 전류를 출력시키는 DC-DC 컨버터의 응용에 매우 적합하다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2005년도 전력전자학술대회 논문집
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• pp.433-435
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• 2005

A new high efficiency active clamp forward converter suitable for the sustaining power module(SPM) of a plasma display panel (PDP) is proposed. It has a wide zero voltage switching (ZVS) range without inserting additional resonant inductor. Also, it features simpler structure, lower cost, less mass, and no effective duty loss. Furthermore, voltages across all rectifier diodes are clamped on the output voltage, which results in a higher efficiency.

• Journal of Power Electronics
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• 제16권3호
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• pp.915-924
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• 2016

A digital self-sustained phase shift modulation (DSSPSM) strategy that allows for good soft switching and dynamic response performance in the presence of step variations is presented in this paper. The working principle, soft switching characteristics, and voltage gain formulae of a LLC converter with DSSPSM have been provided separately. Furthermore, the method for realizing DSSPSM is proposed. Specifically, some key components of the proposed DSSPSM are carefully investigated, including a parameter variation analysis, the start-up process, and the zero-crossing capture of the resonant current. The simulation and experiment results verify the feasibility of the proposed control method. It is observed that the zero voltage switching of the switches and the zero current switching of the rectifier diodes can be easily realized in presence of step load variations.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 하계종합학술대회 논문집(5)
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• pp.103-106
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• 2001

In this paper, a soft switching half-bridge converter using secondary switches for output control and conduction loss reduction is proposed. The conventional half-bridge converter must be fixed on duty cycle for soft switching. The proposed converter was consisted of two added switches in series of the secondary rectifier diodes. The main switches with constant duty cycle are operated ZVS. The secondary switches are operated ZV-ZCS. Especially, the primary switches were fixed duty cycle for maximum voltage conversion ratio. Output of converter is controlled by duty cycle or phase-shifted time of secondary switches. The conduction loss of the proposed converter can be reduced by the secondary switches. The operation characteristic, analysis, simulation and experimental results of the proposed converter are presented.

• Journal of Power Electronics
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• 제7권3호
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• pp.203-212
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• 2007

In this paper, a proposed approach to improve the power factor of three-phase rectifiers and to stabilize the output voltage against load change is presented. The elements of the given control strategy are small size, low cost, high performance, and simplicity. The proposed control strategy of switches is based on a prototype of three bi-directional switched consisting of four diodes and one IGBT. A control technique and operational procedure are also developed, both theoretically and experimentally. The experimental results clearly verify the theoretical analysis from the prototype connected to grid unity.

• Journal of Power Electronics
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• 제14권4호
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• pp.678-686
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• 2014

A novel auxiliary resonant commutated pole (ARCP) link for three-phase PWM voltage-fed converter is presented. The ARCP link consists of two auxiliary switches, one resonant inductance, and six diodes, which is simpler than the conventional ARCP designs. Based on the phase and amplitude control, the proposed converter can take a minimum switching times PWM method, which results in reduced losses and a simplified control. In addition, the zero-voltage resonance modes are analyzed. Finally, simulation and experimental results show that the system can realize zero-voltage switching with a unity power factor.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2007년도 하계학술대회 논문집
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• pp.138-140
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• 2007

A novel AC-DC switching technology is suggested without inductors for one-chip semiconductor. The suggested converter consists of a rectifier diodes, AC source level detector, switching control, detector of over-current and voltage, feedback controller and switching block, The key technology of the proposed AC-DC converting methode is detecting of the low level voltage for AC voltage, power control transistor and rectifying of DC level. The measurement results with commercial devices show that the converter has power efficiency of 66.5% for DC 12V 0.24A and the standby power is 49.58mW at AC 110V.