• 연구논문집
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• 통권28호
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• pp.39-47
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• 1998

Industrial electrostatic precipitation is a very complex process, which involves multiple-way interaction between the electric field, the fluid flow, and the particulate motion. This paper describes a strongly coupled calculation procedure for the rigorous computation of particle dynamics during electrostatic precipitation. The turbulent gas flow and the particle motion under electrostatic forces are calculated by using the commercial computational fluid dynamics (CFD) package FLUENT linked to a finite-volume solver for the electric field and ion charge. Particle charge is determined from both local electrical conditions and the cell residence time which the particle has experienced through its path. Particle charge density and the particle velocity are averaged in a control volume to use Lagrangian information of the particle motion in calculating the gas and electric fields. The turbulent particulate transport and the effects of particulate space charge on the electrical current flow are investigated. The calculated results for poly-dispersed particles are compared with those for mono-dispersed particles, and significant differences are demonstrated.

• 한국안전학회지
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• 제13권3호
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• pp.74-79
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• 1998

To establish measuring method for minimum ignition energy of explosive powders caused by electrostatic discharge, A measuring method(Hartman) using a very small quantity of pine tree testing powder was proposed, and the influence of discharge current limiting resistance connected in series into a capacitive discharge circuit on ignition energies of explosive powders was investigated. As a result the minimum ignition energy was 42.25mJ when discharge current limiting resistance 300 $k\Omega$.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 A
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• pp.169-171
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• 2002

The western route of KEPCO's 765kV transmission line has been tentatively operating as 345kV voltage before commercial operation. After finishing the test operation of 765kV substation in 2002. KEPCO decided to operate the 765kV line for commercial operation. During the applying of 765kV voltage to the transmission line, double circuit transmission line will be operated with two voltage grades of 765kV and 345kV. Because the earthing switch is installed on both end of transmission line, we had estimated the electrostatic induction voltage and electromagnetic induction current before the line energizing in order to confirm the ratings of earthing switch. The induced voltage and current is very important for the maintenance of parallel circuit. This paper describes the simulation study of electrical phenomena such as electrostatic induction voltage from the parallel line and electromagnetic induction current from the parallel circuit. The transmission line model was developed by EMTP (Electro-Magnetic Transient Program).

• 전기학회논문지
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• 제63권10호
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• pp.1417-1422
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• 2014

Using a parallel plate DC plasma system was prepared. Using this equipment, we investigated the basic discharge characteristics of DC argon plasma in terms of electron density, temperature, voltage and current waveforms and plasma potential. The effects of the electrode gap distance, input voltage, ballast resistance and pressure were measured using electrostatic probe. Plasma simulation using fluid approximation has been performed. External circuit effects was included in the simulation. Measured and calculated current voltage characteristics show similar tendencies.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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• pp.140-141
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• 2006

Background doping concentration (BDC) is proven to be a critical factor to affect the high current behavior of the extended drain NMOSFET (EDNMOS) devices. The EDNMOS device with low BDC suffers from strong snapback in the high current region, which results in poor electrostatic discharge (ESD) protection performance and high latchup risk. However, the strong snapback can be avoided in the EDNMOS device with high BDC. This implies that both the good ESD protection performance and the latchup immunity can be realized in terms of the EDNMOS by properly controlling its BDC.

• Journal of Astronomy and Space Sciences
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• 제3권2호
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• pp.71-79
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• 1986

최근에 알려진 위성이나 로켓트 데이타로부터 지구자기장에 수직인 방향으로 이온이 가속화된다는 사실, 즉 ion conics를 알고 있다. 이 현상과 오로라존에서 자주 발견되는 정전기적 파동이 밀접하게 관련된다고 믿고 있다. 플라스마 이론과 1 차원의 모의실험에 입각하여 전류에 의한 플라스마 불안정성의 선형과 비선형이론을 고려한다. 모의실험으로부터 이온의 가속현상이 일어남을 볼 수 있다.

• Journal of Biosystems Engineering
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• 제29권1호
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• pp.21-28
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• 2004

Spraying is one of the most efficient methods for pesticide and insecticide control. Generally, orchard sprayers(aircarrier sprayer) are used for such applications. However, when an orchard sprayer is used, only 20% of total amount of spray deposits on the target. The rest of spray are not only wasted but are also potential sources of environmental pollution. The research far the development of electrostatic spraying system for orchard sprayer was conducted to develop the new pesticide application technology for the reduction of environmental pollution and f3r the production of safe agricultural products. The spray characteristics for nozzles with the different charging methods were tested and the effect of electrostatic charge was analyzed, in the laboratory experiments. The results of this study indicate that the capacitive type of electrostatic spraying nozzle exhibits a large current deposition of water sprays on the sample target. The covering area ratio by conventional spraying system was 10.2%, while that of electrostatic sprays with pulse induction charging method gave the increased covering area ratio by 4.3 times.

• 한국위성정보통신학회논문지
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• 제7권2호
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• pp.18-24
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• 2012

본 논문에서는 ESD 방지를 위한 최적 방법론에 목표하여 확장된 드레인을 갖는 EDNMOS 소자의 더블 스냅백 현상 및 백그라운 도핑 농도 (BDC)의 영향을 조사하였다. 고전류 영역에서 낮은 BDC를 가진 EDNMOS 소자는 강한 스냅백으로 인해 취약한 ESD 성능과 높은 래치업 위험을 가지게 되나, 높은 BDC를 가진 EDNMOS 소자는 스냅백을 효과적으로 방지할 수 있음을 알 수 있었다. 따라서 BDC 제어로 안정적인 ESD 방지 성능과 래치업 면역을 구현할 수 있음을 밝혔다.

• 조명전기설비학회논문지
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• 제23권1호
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• pp.109-115
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• 2009

본 논문은 백열등 부하 전기설비에서 측정한 전류 파형으로 전기사고 징후를 조기에 검출하기 위한 것이다. 첫째, 저항성 회로에서 전류 모니터의 특성을 분석하였다. 둘째, 백열등을 부하로 하는 전기설비를 구축하고, 전기설비의 일부에서 KS C IEC(Korea Standard C International Electrostatic Commission) 60112에 따라 트래킹을 발생시켜 사고를 모의하였다. 전기사고 징후는 전류 모니터로 측정한 전류파형을 분석함으로써 검출되었다. 그 결과 부하의 수에 관계없이 사고의 최종 단계인 트래킹으로 진전되어 갈수록 전류 파형에는 점점 큰 전류 펄스가 보였고 출현빈도도 더욱 높아졌다.

• 대한전자공학회논문지SD
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• 제42권12호
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• pp.9-12
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• 2005

본 연구는 물리전지의 하나로서 정전기 전지를 제안한 것으로 정전기를 활용한 전지의 제작 가능성을 정전기 전지의 구조제안, 동작원리에 대한 설명 및 특성변수의 계산을 통해 제시하였다. 구체적으로는 소자 외부에서 정전발전기를 통해 발생시킨 전하를 PN접합의 SCR내에 주입하고 SCR내의 내부전계를 이용하여 주입된 전하를 이동시켜 전지의 역할을 할 수 있도록 한 것이다. 계산 결과, 정전기 전지 소자의 단면적을 $0.0001cm^2$로 하고 정전발전기를 이용하여 발생시킨 약 $10^{11}$개의 전하를 주입했을 때, 0.15mA의 전류가 발생하여 전지로서의 가능성이 있음을 보였다.