• Journal of Korean Society of Environmental Engineers
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• v.35 no.5
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• pp.356-362
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• 2013

An attempt has been made to optimize elongated rotating arc plasma $NH_3$ scrubber. Among diverse semiconductor processes, diffusion and implantation process inevitably produce $NH_3$ as byproduct and efficient dry process for the decomposition of $NH_3$ is required. Plasma process does not produce NOx that is commonly produced in combustion process and there is no problem of deactivation, usually experienced in catalyst process. However, plasma process uses electrical energy and needs to be optimized to achieve feasibility of application. In this work, mode control of rotating arc is presented as tentative solution for the possible optimization of the process. Based on existing rotating arc, scale-up and following mode mapping was tried. Proposed reactor design was evaluated in the $NH_3$ decomposition process and revealed that optimization scheme is at hand. In the experiment of full scale scrubber including heat exchanger, the process gave more stable and efficient process of $NH_3$ decomposition.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.5 no.4
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• pp.35-42
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• 1991

Recently, HID lamps have been considered as important in regard to the trend of energy saving, and increasingly and diversely used in various ways. This paper will show the simulating models concerning high-pressure arc discharge system directly applicable for its design and manufacture, and analyze its various characteristics. For warm-up characteristics, the evaporating process of inner atoms is described in terms of second-order differential equation: for the thermal conduction from are axis to discharge wall and outer bulb, its transfer process is introduced according to five first-order differential equations. Under the steady state satisfying LTE, the time-variant characteristics are suggested by means of time-dependent energy balance equation derived from fluid equations, approximation of radiation energy and material functions in the discharge tube. The simulating models concerning these equations are then applied for high-pressure mercury lamp.

• Proceedings of the IEEK Conference
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• 2005.11a
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• pp.1283-1286
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• 2005

Arc Fault Current is an electric discharge which is occurred in two opposite electrode. In this paper, arc current control algorithm is designed for the interruption of arc fault current which is occurred in the local electric network. This arc is one of the main causes of electric fire. Arc fault in electrical network has the characteristics of low current, high impedance and high frequency. Conventional arc current controller does not have the arc current interrupt function. Hence, Controller of arc current is designed for the interruption of arc fault current which has the modified arc characteristics.

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.130-130
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• 2015

플라즈마를 이용한 cleaning, etching, sputtering 공정에서 발생하는 마이크로아크방전이나 turn-off후의 잔류정전기는 공정대상물의 절연파괴나 전자소자에 전기적 손상을 유발함으로서 공정의 불량률을 증가시키는 중요한 요인이 된다. 본 연구에서는 잔류정전기를 관찰하기위하여 실린더형 챔버구조의 평행평판 전극구조를 지닌 용량결합형 플라즈마에서 powered electrode에 부착된 유전체 기판 표면의 잔류 정전기의 변화 양상을 planar type probe로 측정해보았다. 300mtorr 압력에서 아르곤가스로 발생시킨 플라즈마가 존재할 때 낮은 음전위 평균값을 가지던 기판표면 전위가 전력인가가 중지되었을때 20V 가량의 양전위를 가질 수 있음을 측정 하였고, 이것을 COMSOL MULTIPHYSICS TOOL을 활용한 시뮬레이션과 비교하였다. 이 현상이 파워인가 전극이 플라즈마 영역에 노출되느냐에 따라 발생할 수 있음을 알게 되었고, 그 크기와 지속시간은 입력전력 및 블로킹 커패시터와 유전체 기판의 정전용량에 의존함을 확인 하였다.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.189-190
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• 2011

현재 변전소에서 일반적으로 사용되는 송변전기기 개폐장치인 GIS(GAS Insulated Switchgear)는 절연확보를 위해 외함 내부에 SF6 GAS가 충진되는 구조이다. SF6 GAS는 지구온난화 규제 물질에 해당하는 가스로 아크 및 부분방전 등에 의해 유독물질로 분해되는 특징이 있어 개폐장치의 내부 절연물로 친환경 매질로의 전환이 절실한 실정이다. 최근 KEPCO는 25.8kV GIS를 대체할 친환경절연 개폐장치를 도입하고 시범 운영중에 있으며, 그 결과에 따라 확대 적용할 방침이다.

• Journal of Powder Materials
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• v.10 no.1
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• pp.51-56
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• 2003

To investigate the effect of the parameters of the plasma arc discharge process on the particle formation and particle characteristics of the iron nano powder, the chamber pressure, input current and the hydrogen volume fraction in the powder synthesis atmosphere were changed. The particle size and phase structure of the synthesized iron powder were studied using the FE-SEM, FE-TEM and XRD. The synthesized iron powder particle had a core-shell structure composed of the crystalline $\alpha$-Fe in the core and the crystalline $Fe_3O_4$ in the shell. The powder generation rate and particle size mainly depended on the hydrogen volume fraction in the powder synthesis atmosphere. The particle size increased simultaneously with increasing the hydrogen volume fraction from 10% to 50%, and it ranged from about 45nm to 130 nm.

• Journal of Powder Materials
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• v.11 no.4
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• pp.328-332
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• 2004

Fe nanopowders were successfully synthesized by plasma arc discharge (PAD) process using Fe rod. The influence of chamber pressure on the microstructure was investigated by means of X-ray Diffraction (XRD), Field Emission Scanning Electron Microscope (FE-SEM), Transmission Electron Microscopy (TEM) and X-ray Photoelectron Spectroscopy (XPS). The prepared particles had nearly spherical shapes and consisted of metallic cores (a-Fe) and oxide shells (Fe$_{3}$O$_{4}$), The powder size increased with increasing chamber pressure due to the higher dissolution and ejection rate of H$_2$ and gas density in the molten metal.

• Proceedings of the KIPE Conference
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• 2008.06a
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• pp.351-353
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• 2008

최근에 환경친화적인 관점에서 많은 형태의 무수은을 이용한 형광램프가 연구되어오고 있다. 그 중에서도 제논을 이용한 형광램프는 수은을 대체하는 방전기체의 조건을 만족하고 있다. 따라서 제논을 이용한 면광원의 구동 시 지금의 수은이 들어간 광원의 구동에 있어서 안정기요건이 차이가 있으므로, 본 논문에서 제논을 이용한 면광원을 위한 안정기를 제안한다. 제안된 면광원 안정기는 크게 AC입력 측의 PFC (power factor correction)부분과 면광원을 구동하는 인버터 부분으로 구성되어있다. 특히, 인버터 부분에서는 제논 면광원의 특성에 대응하기 위해서 정전력회로, 아크 방지 기동회로 등이 포함되어 있다.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.36 no.9
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• pp.655-659
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• 1987

This study presents a model of the electrical characteristics of the high-pressure mercury vapour arc discharge. Energy balance equation per unit volume of the arc tube is converted into the one per unit length by assuming the parabolic radial temperature distribution and integrating over the cross-section of the tube. Using this energy balance equation, together with the circuit equation and Ohm's law, the arc voltage and current variation for 1 cycle is numerically calculated and a good result is obtained. A simple method to calculate the axis temperature of the arc tube and the radiation output is also presented.

• Proceedings of the KIEE Conference
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• summer
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• pp.602-603
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• 2004

전력용 변압기에 아크나 코로나가 발생하여 국부가열이 존재하면 절연유나 절연지가 분해하여 저분자의 탄화수소, 수소, 탄화가스, 일산화탄소 둥이 발생하여 절연유에 용해된다. 절연유에 용해된 가스를 실시간 분석하여 변압기의 이상을 조기에 발견하여 운전의 효율성을 높이고 고장을 사전에 예방하기 위한 기술이 전개되고 있다. 경제적인 측면에서 단일 수소가스 검출센서가 널리 보급되어 실용화되고 있는 실증이다. 이 논문에서는 전력용 변압기의 국부적 고온인 경우의 가열온도, 가열시간 및 방전에 대하여 수소가스 주도형 센서의 응답특성에 관하여 고찰하였다.