• 전력전자학회:학술대회논문집
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• 전력전자학회 2008년도 하계학술대회 논문집
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• pp.400-402
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• 2008

A new interleaved forward converter, adopting series-input parallel-output structure with a common transformer reset circuit, is proposed in this paper. Series-input structure distributes the voltage stress on switches, which makes it suitable for high input voltage application. Paralleling output stage with an interleaving technique enables the circuit handle large output current and reduces filter size. In addition, since two forward converters share one active-clamp circuit for the transformer reset, its primary structure is simplified. All these features make the proposed converter promising for high input voltage applications with high efficiency and simple structure.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2004년도 전력전자학술대회 논문집(2)
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• pp.615-619
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• 2004

A new asymmetrical zero voltage switching (ZVS) active clamp forward converter is proposed. Since the ripple current of secondary inductor plays a key role in the ZVS operation of main power switch, the proposed converter shows an excellent ZVS performance. The synchronous rectification is employed to reduce the rectification loss. The operational principle and ZVS analysis are presented. Experimental results demonstrate that the proposed converter can achieve an excellent ZVS performance throughout all load conditions and the significant improvement in the efficiency for the 100W(5V,20A) prototype converter.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2008년도 하계학술대회 논문집
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• pp.505-507
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• 2008

A conventional active-clamp forward (ACF) converter is a favorable candidate in low-to-medium power applications. However, the switches suffer from high voltage stress, i.e., sum of the input voltage and the reset capacitor voltage. Therefore, it is not suitable for high input voltage applications such as a front-end converter of which the input voltage is about 400-$V_{dc}$. To solve this problem, three-switch ACF (TS-ACF) converter, which employs two main switches and one auxiliary switch with low voltage stress, is proposed. Utilizing low-voltage rated switches, the proposed converter is promising for high input voltage applications with high efficiency and low cost.

• Journal of Power Electronics
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• 제15권1호
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• pp.86-95
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• 2015

An active clamp high step-up boost converter with a coupled inductor is proposed in this paper. In the proposed strategy, a coupled inductor is adopted to achieve a high voltage gain. The clamp circuit is included to achieve the zero-voltage-switching (ZVS) condition for both the main and clamp switches. A rectifier composed of a capacitor and a diode is added to reduce the voltage stress of the output rectifier diode. As a result, diodes with a low reverse-recovery time and forward voltage-drop can be utilized. Since the voltage stresses of the main and clamp switches are far below the output voltage, low-voltage-rated MOSFETs can be adopted to reduce conduction losses. Moreover, the reverse-recovery losses of the diodes are reduced due to the inherent leakage inductance of the coupled inductor. Therefore, high efficiency can be expected. Firstly, the derivation of the proposed converter is given and the operation analysis is described. Then, a steady-state performance analysis of the proposed converter is analyzed in detail. Finally, a 250 W prototype is built to verify the analysis. The measured maximum efficiency of the prototype is 95%.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 D
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• pp.2201-2202
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• 2006

In this paper, we designed high performance, high quality and high density switch mode power supply for precision electronics, and communication equipments. For this, we used two parallel DC-DC converters, which have opposite phases, to support proper high performance and high quality power. To reduce switching losses and make high switching frequency, active-clamp and ZVS technique were employed in each converter.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 A
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• pp.569-570
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• 2006

In this paper, we designed high performance, high quality and high density switch mode power supply for precision electronics, and communication equipments. For this, we used two parallel DC-DC converters, which have opposite phases, to support proper high performance and high quality power. To reduce switching losses and make high switching frequency, active-clamp and ZVS technique were employed in each converter.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 B
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• pp.1235-1236
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• 2006

In this paper, we designed high performance, high quality and high density switch mode power supply for precision electronics, and communication equipments. For this, we used two parallel DC-DC converters, which have opposite phases, to support proper high performance and high quality power. To reduce switching losses and make high switching frequency, active-clamp and ZVS technique were employed in each converter.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 C
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• pp.1695-1696
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• 2006

In this paper, we designed high performance, high quality and high density switch mode power supply for precision electronics, and communication equipments. For this, we used two parallel DC-DC converters, which have opposite phases, to support proper high performance and high quality power. To reduce switching losses and make high switching frequency, active-clamp and ZVS technique were employed in each converter.

• JSTS:Journal of Semiconductor Technology and Science
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• 제7권2호
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• pp.94-97
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• 2007

The desin and implementation of a CMOS analog integrated circuit that provides dual-mode modulations, PWM for active clamp reset converter and PFM for LLC resonant converter, is described. The proposed controller is capable of implementing programmable soft start and current-mode control with compensating ramp for PWM and frequency shifting soft start for PFM. Also it provides delay time for both modes. PWM mode is implemented by active clamp reset converter and PFM mode is implemented by LLC resonant convereter, respectively. The chip is fabricated using the 0.6um high voltage CMOS process.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2002년도 전력전자학술대회 논문집
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• pp.374-377
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• 2002

This paper presents dynamic analyses and control design of the current-mode controlled active-clamp forward-flyback converter. The circuit averaging technique is used to extract the small-signal circuit model for the power stage From the small-signal circuit model of the power stage, the open-loop transfer functions are derived and used for the compensation design. The analysis results are verified using an experimental converter that delivers a 3.3V/10A output from a $40\~60V$ input source.