• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.22 no.4
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• pp.35-45
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• 2008

This paper present the Three-Level converter using IM(Integrated Magnetics) method for high power application. In power conversion system, magnetic components are important devices used for energy storage, energy transfer, galvanic isolation and filtering. The proposed Three-Level converter is to reduce the number of magnetic components using transformer integrated with output inductor. This paper proposes reluctance model base on the magnetic analysis for the Three-Level converter. Also, the secondary rectification was discussed by a single core transformer winding. A protype featuring 540[V] input, 48[V] output, 40[kHz] switching frequency, and 3[kW] output power using IGBT.

• The Transactions of the Korean Institute of Power Electronics
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• v.20 no.5
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• pp.437-447
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• 2015

In this paper, implementation of an integrated transformer applicable to power supply units (PSUs) for a 150-W LED with a wide range of output voltage is presented. The transformer is comprised of a PFC inductor and an LLC resonant transformer, each of which is placed and integrated on an E-I-E-type magnetic core. Integrated transformers with two different air gap topologies (i.e., the side and center gap topologies) are considered in the design phase to investigate their applicability. The design consideration on the LLC resonant converter used for the wide-output-voltage control ranges is described, and the overall performance of the proposed system is verified through realization of it onto a 150-W LED PSU board.

• The Transactions of the Korean Institute of Power Electronics
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• v.15 no.2
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• pp.119-126
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• 2010

An integrated magnetic (IM) transformer is proposed for a phase shifted full bridge (PSFB) converter with zero voltage switching (ZVS). In a proposed IM transformer, the transformer is located on the center leg of E-core and the output inductor is wound on two outer legs with air gap. The proposed IM transformer is analyzed by using the magnetic capacitor model. For reducing the core size, EE core is redesigned. The proposed IM transformer is experimentally verified on a 1.2 kW prototype converter. The converter efficiency with the proposed IM transformer is about 93 % at full load and its volume size can be reduced. It can be expected that the power density can be largely increased with the proposed IM transformer.

• The Transactions of the Korean Institute of Power Electronics
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• v.13 no.5
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• pp.396-402
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• 2008

This paper presents the structure and performance of a new Integrated magnetics-based transformer, which can be readily adapted to zero-voltage switching full bridge dc-to-dc converters. The proposed transformer features with two paralleled primary windings and a center-tapped secondary winding. The transformer can be fabricated on standard EE or EI cores where the primary and secondary windings are placed on the outer legs while the output filter inductor is wound on the middle leg. The performance of the proposed transformer is demonstrated with a 100 kHz 720 W experimental dc-to-dc converter which recorded a 92% conversion efficiency at 12 V output voltage.

• Proceedings of the KIPE Conference
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• 2008.06a
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• pp.40-42
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• 2008

This integrated magnetic (IM) transformer is proposed for a phase shifted full bridge (PSFB) converter with zero voltage switching (ZVS). In a new IM transformer, the transformer is located on the center leg of E-core and the output inductor is wound on two outer legs. The proposed circuit is analyzed electrically and magnetically. An E-core is redesigned and implemented. The proposed IM transformer is experimentally compared with the conventional one through a 1.2kW prototype converter.

• Proceedings of the KIEE Conference
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• 2003.07b
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• pp.1232-1234
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• 2003

The push pull forward converter is a very suitable circuit for low output voltage, high output current applications with a wide input voltage range. This converter can be miniaturized by integrate magnetic components such as the output inductor, the transformer and the input inductor. We considered of the efficiency for the push pull forward converter. Developed the push pull forward converter rating are of $36{\sim}72V$ input and 3.3V/30A output. In this converter. the efficiency was measured by 76.4% at full load and 82.95% at half load. The maximum efficiency is up to 83.% at 200kHz, 11A output.

• Proceedings of the KIPE Conference
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• 2003.07a
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• pp.36-39
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• 2003

The push pull forward converter is a very suitable circuit for low output voltage, high output current applications with a wide input voltage range. All the magnetic components (output inductor, transformer, input filter) can be integrated into a single core. The integrated magnetics can reduce the number of the magnetic components. Developed the push pull forward converter rating are of 36 $\~$72V input and 3.3V/30A output. In this converter, the efficiency was measured by $76.4\%$ at full load and 82.95$\%$ at full load. The maximum efficiency is up to 83.$\%$ at 200kHz switching frequency, l1A output.

• Journal of Power Electronics
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• v.13 no.5
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• pp.766-778
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• 2013

The depletion of natural resources and renewable energy sources, such as photovoltaic (PV) energy, has been highlighted for global energy solution. The PV power control unit in the PV power-generation technology requires a high step-up DC-DC converter. The conventional step-up DC-DC converter has low efficiency and limited step-up ratio. To overcome these problems, a novel high step-up DC-DC converter using an isolated switched capacitor cell is proposed. The step-up converter uses the proposed transformer and employs the switched-capacitor cell to enable integration with the boost inductor. The output of the boost converter and isolated switched-capacitor cell are connected in series to obtain high step-up with low turn-on ratio. A hardware prototype with 30 V to 40 V input voltage and 340 V output voltage is implemented to verify the performance of the proposed converter. As an extended version, another novel high step-up isolated switched-capacitor single-ended DC-DC converter integrated with a tapped-inductor (TI) boost converter is proposed. The TI boost converter and isolated-switched-capacitor outputs are connected in series to achieve high step-up. All magnetic components are integrated in a single magnetic core to lower costs. A prototype hardware with 20 V to 40 V input voltage, 340 V output voltage, and 100 W output power is implemented to verify the performance of the proposed converter.

• Proceedings of the KIPE Conference
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• 2007.07a
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• pp.126-128
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• 2007

This paper presents a new soft switching dc-to-dc converter that employs IM transformer. Detailed analysis and design considerations of the proposed circuits are presented. By applying the proposed magnetic integration procedure, new integrated magnetic circuits featuring low loss, simple structure are then developed to overcome the limitations of prior art. Consequently, the power loss and the size of the integrated magnetic device are greatly reduced. The operation and performance of the proposed converter are demonstrated with an experimental converter that delivers a 5V/5A output from a 48V input at the maximum efficiency of 90 %.

• The Transactions of the Korean Institute of Power Electronics
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• v.10 no.6
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• pp.592-597
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• 2005

The push pull forward converter is suitable in a low output voltage, a high output current applications with wide input voltage ranges. All magnetic components including output inductor, transformer and input filter can be integrated into single EI/EE core. The integrated push pull forward converter is considered through the comparison of efficiency according to the circuit parameters. The Nicera company's 5M FEE18/8/10C and NC-2H FEI32/8/20 cores are used for the transformer. The integrated push pull forward converter ratings are of $36\~72V$ input and 3.3V/30A output. In case that NC-2H FEI32/8/20 core used in the converter, the efficiency is measured up to $83.5\%$ at the switching frequency 200 kHz and the 11A load. The efficiencies of $76.4\%$ at a full load and $82.95\%$ at a half load are measured.