• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 추계학술대회 논문집 학회본부A
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• pp.137-140
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• 1998

A new SPWM inverter using three-phase boost converter by auxiliary partial resonant with high power factor and high efficiency is proposed. The proposed boost converter is constructed by using a resonant network in parallel with the switch of the conventional boost converter. The devices are switched at zero voltage or zero current eliminating the switching loss. A new Partial resonant boost converter achieves zero-voltage switching (ZVS) or zero-current switching (ZCS) for all switch devices without increasing their voltage and current stresses. This paper introduces elimination of low-order harmonics compared with conventional SPWM inverter and SPWM inverter using three-phase boost converter by auxiliary Partial resonant.

• 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.

• ETRI Journal
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• 제36권5호
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• pp.835-840
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• 2014

New ways of achieving small, multiband, multifunctional, and standard solutions for mobile handset antennas are demanded in the current wireless market. A non-resonant element of $5mm{\times}5mm{\times}5mm$, a matching network, and a $100mm{\times}40mm$ slotted ground plane are proposed to satisfy mobile market demands that require multiband operation and small antenna solutions. The main advantage of the proposed design is that with only one non-resonant element of considerably small size ($0.015{\lambda}$, 900 MHz), the handset is capable of providing operation at mobile bands.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2019년도 전력전자학술대회
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• pp.142-144
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• 2019

Nowadays, multi-MHz wireless power transfer (WPT) system has received a great concern of study due to its desirable characteristics such as user convenience, system compact and better safety as compared to the conventional DC-DC with cord. This paper presents a solution for WPT Lithium Batteries charger with Constant Current (CC) and Constant Voltage (CV) charging process. The proposed system consists of a high frequency class D power amplifier, a pair of PCB coil, transformable high-order resonant network and a full-bridge rectifier. The charger can be implemented CC /CV charging profile thanks to automatic reconfigurable resonant compensator. Therefore, the battery can be fully charged without the help of an additional DC/DC converter. The simulation and 50W-6.78-MHz hardware experimental results are presented to verify the feasibility of the proposed method and to evaluate the performance of the proposed wireless battery charger.

• 전력전자학회논문지
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• 제17권4호
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• pp.281-290
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• 2012

This paper describes a Cross-regulation characteristics of a multi-output LLC resonant converter widely used in consumer electronics. The output characteristics of the multi-output LLC converter is derived from the assumption that the current and voltage in the resonant network is sinusoidal and the duty loss exists. The simulation and experimental results are provided to verify the theoretic results.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제48권4호
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• pp.212-218
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• 1999

A new partial resonant three phase boost converter with high power factor and high efficiency is proposed. The proposed boost converter is constructed by using a resonant network in parallel with the swithch of the conventional boost converter. The devices are switched at zero voltage or zero current eliminating the switching loss. A new auxiliary partial resonant boost converter achieves zero-voltage switching(ZVS) or zero-current switching(ZCS) for all switch devices without increasing their voltage and current stresses.

• 전자공학회논문지SC
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• 제47권1호
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• pp.62-66
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• 2010

순수한 수동소자들을 사용하여 영전류 영전압에서 소프트하게 스위칭 동작하는 펄스 폭 변조 의사 공진 컨버터를 소개한다. 사용된 수동 소자망은 폴딩 스너버망의 변형된 형태로 컨버터의 주 정류 다이오드의 역 복귀 전류를 제거시켜 주고 스위칭 소자 MOSFET를 소프트하게 스위칭 시킨다. 효율도 능동 스너버형과 비슷한 수준이고 회로 구성이 간단하여 구현하기 쉬우며 중 출력(수 KW이하) 정전압 공급원에 적합하다.

• 조명전기설비학회논문지
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• 제16권5호
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• pp.7-13
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• 2002

고효율 고전력 밀도를 제공하는 공진형 컨버터에 있어서 스위치에 걸리는 전압 스트레스는 입력전압의 4∼5배 정도여서, 높은 정격의 소자를 필요로 하기 때문에 전도손실을 증가시킨다. 본 논문에서는 이러한 문제점을 해결하기 위해 제안했던 교번으로 동작하는 포워드 다중공진형 컨버터에 적용한 회로 형태를 다른 컨버터에 적용한 예를 제시하였다. 그리고 제안한 AT포워드 다중공진형 컨버터의 루프 이득 특성을 알아보기 위해 HP4194A 네트워크 해석기를 이용해 실험적으로 측정한 결과에 대해 고찰하였다.

• 전력전자학회논문지
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• 제17권4호
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• pp.298-305
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• 2012

This paper proposes a soft switching boost converter with an auxiliary resonant circuit. The auxiliary resonant circuit is added to a general boost converter and that is composed of one switch, one diode, one inductor and two capacitors. The resonant network helps the main switch to operate with a zero voltage switching(ZVS) and auxiliary switch also operates under the zero voltage and zero current conditions. The soft switching range is extended by the auxiliary switch and it is possible to control the proposed converter with a pulse width modulation(PWM). The ZVS and ZCS techniques make switching losses decreased and efficiency of the system improved. A theoretical analysis is verified through the simulation and experiment.

• 전력전자학회논문지
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• 제23권3호
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• pp.208-216
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• 2018

In this paper, an LLC resonant converter employing two coupled inductors on the secondary side of the converter is proposed. The conventional LLC converter exhibits serious power loss during secondary winding of the transformer because of generation of tremendous output current ripples. To overcome this problem, an LLC resonant converter with a current doubler as a rectifying circuit was recently proposed. However, the current-doubler rectifying circuit requires coupled inductors with a high coupling ratio to retain the designed resonance characteristics. Therefore, an additional hardware filter is required at the output stage to address large output current ripples. Additional design procedures are also necessary because the inductance component of the added filter affects the designed resonant network. To solve this issue, an LLC resonant converter employing two coupled inductors is proposed in this paper. Mathematical analysis shows that the proposed secondary-side current-doubler circuit does not affect the designed resonance characteristics. The operating principles and theoretical analyses are proven through a simulation and experiments with a 54 V/28 A prototype.