• 대한금속재료학회지
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• 제50권5호
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• pp.369-374
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• 2012

Nanopowders of Mo, Ta and Si were made by high-energy ball milling. A dense nanostructured $MoSi_2-TaSi_2$ composite was sintered by the high-frequency induction heated combustion method within 2 minutes from mechanically activated powder of Mo, Ta and Si. A highly dense $MoSi_2-TaSi_2$ composite was produced under simultaneous application of a 80 MPa pressure and the induced current. Mechanical properties and microstucture were investigated. The hardness and fracture toughness of the $MoSi_2-TaSi_2$ composite were $1200kg/mm^2$ and $3.5MPa.m^{1/2}$, respectively. The mechanical properties were higher than those of monolithic $MoSi_2$.

• 대한금속재료학회지
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• 제49권9호
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• pp.715-719
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• 2011

Nanopowders of $Fe_3N$ and Si were fabricated by high-energy ball milling. A dense nanostructured $12Fe-Si_3N_4$ composite was simultaneously synthesized and consolidated using a high-frequency induction-heated sintering method for 2 minutes or less from mechanically activated powders of $Fe_3N$ and Si. Highly dense $12Fe-Si_3N_4$ with a relative density of up to 99% was produced under simultaneous application of 80 MPa pressure and the induced current. The microstructure and mechanical properties of the composite were investigated.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 A
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• pp.495-497
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• 1996

This paper proposes LCC type high frequency resonant inverter to be used as a source of induction heating device or ultrasonic device and considers of operating characteristic for it. The inverter is operated safely over wide range load, because it has both panel loaded capacitor and series loaded capacitor. Then, switching frequency of the inverter is controlled by feedback voltage and current in order to have constant output power even when load is varied.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2000년도 전력전자학술대회 논문집
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• pp.360-363
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• 2000

A half bridge type double resonant high frequency resonant inverter using PFM is described. This proposed inverter can reduce distribution of the switching current because of using the current of the serial resonant circuit to the input current of the parallel one. In the case of variable capacitance of the DC voltage source separated capacitor the analysis of inverter circuit has generally described by using normalized parameter and operating characteristics has been evaluated in terms of switching frequency and parameters. Based on the characteristics value a method of the circuit design is proposed. The theoretical results are in good agreement with the experimental ones. In the future this proposed circuit is considerated to be useful for induction heating and discharge lamp.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 F
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• pp.2638-2640
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• 1999

This paper proposes a current-fed type high frequency inverter using a soft switching technology Zero-Voltage-Switching to reduce turn on and off loss at the switching. The analysis of the proposed circuit was described by using normalized parameter and operating characteristics have been evaluated as to switching frequency and parameters. In the future, the proposed circuit is considered to be useful for induction heating applications.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2000년도 학술대회논문집
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• pp.169-172
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• 2000

This paper describes a Push-Pull type high frequency resonant inverter composed of consolidation of boost converter circuit and resonant inverter circuit. By using a boost converter circuit, the proposed inverter can obtain a twice input voltage of resonant circuit and reduce a secondary turn ratios. also, by using both switching device of boost-converter and resonant circuit, the number of switching device can be reduced by half, the analysis of the proposed circuit was generally described by using normalized parameter and operating characteristics have been evaluated as to switching frequency and parameters. In the future, this proposed inverter shows that is can be practically used as a power source system for the lighting equipment of discharge lamp, induction heating applications.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 학술대회 논문집 전문대학교육위원
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• pp.153-157
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• 2002

Electricity living body formation operation appliance is using most imports until present. And, because electricity living body formation operation appliance is too expensive, it becomes burden to buy in small scale hospital. Also, problem that economical damage by income is added follows, Therefore, this treatise developed electricity living body formation operation appliance by home production, Ultra high frequency eruption circuit used LC circuit, and output frequency is possible to 8 [MHz], and output voltage amplified maximum 800 [V]. This operation appliance could display size of fixed current. This developed product could microscopic operation fewer than 1 [mm]. This development technology is considered by do metallic surface heat treatment, melting, welding, induction heating device and that can apply to domestic animals surgical operation and so on.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 춘계합동학술대회 논문집
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• pp.127-132
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• 2002

Electricity living body formation operation appliance is using most imports until present. And, because electricity living body formation operation appliance is too expensive, it becomes burden to buy in small scale hospital. Also, problem that economical damage by income is added follows. Therefore, this treatise developed electricity living body formation operation appliance by home production. Ultra high frequency eruption circuit used LC circuit. and output frequency is possible to 8 [MHz], and output voltage amplified maximum 800 [V]. This operation appliance could display size of fixed current. This developed product could microscopic operation fewer than 1 [mm]. This development technology is considered by do metallic surface heat treatment, melting, welding, induction heating device and that can apply to domestic animals surgical operation and so on.

• 조명전기설비학회논문지
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• 제12권1호
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• pp.51-57
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• 1998

본 논문은 구동신호 위상제어 기능을 갖는 SIT고주파공진 인버터를 제안하였다. SIT를 이용한 위상제어형인버터는 낮은 스위칭 손실로서 높은 스위칭 주파수의 전력변환을 실현시킬 수 있다. 특히 2단위 인버터의 출력전압을 직렬로 연결하여 높은 출력을 얻을 수 있다. 과전류에 대해서 보호회로를 이용한 시스템의 안정성과 그리고 PLL에 의해 부하변화에 따른 자동추종제어를 실현하였다. 특히 제안된 인버터는 고주파에서도 거의 정현파에 가까우며, 스위칭 주파수 범위는 180∼220〔kHz〕이고, 2〔kW〕의 유도가열에 응용하였다. 본 인버터의 동작 특성에 대해서 이론과 실험결과를 비교 검토하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 B
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• pp.1105-1107
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• 2001

본 연구에서 제안한 가변 출력 직렬공진 고주파 유도가열시스템은 기존 공진회로 트랜스 1차에 여러 개의 탭 제작과 공진회로의 콘덴서를 직, 병렬로 연결하는 등의 간단한 설계방법으로 주파수와 출력을 가변 시켜 실험함으로서 유도가열 시스템 1대로 다양한 피 가열부품 등에 적용시킬 수 있음을 확인할 수 있었다.