• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.9 no.6
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• pp.802-812
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• 1998

Safety related to electric field exposure for the personnel of high voltage power plant and substation is of importance. To analyze the induced current influencing on human body in this paper, we calculate directly capacitance in three dimension which is complex and time consuming, as not to separate the voltage source and the induced object using a effective modeling technique. The proposed algorithm in this paper has been applied to 765 kV high voltage transmission line to evaluate human hazard for the induced current through the case study. As the results, the short circuit current of human body has been identified in the range of 0.3 mA to 6.8 mA. Closing to transmission line, this range of short current can exceed 5 mA that ANSI recommended let-go current. Therefore, it is necessary to countermeasure such as putting on conductive clothing in live-line maintenance of transmission line.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.19 no.2
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• pp.55-62
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• 2005

There are many risk factors of electrical shock caused by a minimum of protective devices, loose working environments, deterioration of installations at temporary power installations of construction sites. An insulation cover for instrument transformer(MOF) used in 22.9[kV] class power receiving system hasn't shown good performance in terms of electrical safety because of short clearance between insulation cover and each input and output wire junction part. The insulation cover is easily moved by outside environment as wind or rain because of different size between insulation cover and busing, also can be leaded to breakdown by tracking. Therefore, we have proposed the insulation cover which effectively can prevent from electrical disaster in this paper, and a utility model patent had been registered already. To decrease the electric field concentrated on specific part, we had roundly designed the shape of insulation cover and the clearance between cover and live part was adjusted to be longer than the existing thing. The proposed insulation cover was evaluated by using the electric field solution program.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.3
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• pp.45-54
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• 2004

Microwave characteristics of ridge type CPW traveling-wave(TW) electroabsorption modulator and photodetector are affected by the thickness of intrinsic layer, width of guiding layer, and the separation of signal and ground electrodes. These factors are determined effective index of microwave and characteristic impedance due to changing of capacitance(C) and inductance(L) of device. However, conventional equivalent circuit of TW-structure is approximated to microstrip and CPW transmission line by distribution of electric and magnetic fields, respectively. In this paper, we analyzed microwave characteristics of TW-structure and found more accurate value of C and L by using finite difference time domain (FDTD) method. These values are adopted circuit element of equivalent circuit. Microwave characteristics obtained by the FDTD and equivalent circuit model show good agreement.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.45 no.4
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• pp.49-56
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• 2008

This paper introduces a compact analytical current conduction model of long-channel depletion-mode n-type nanowire field-effect transistors (NWFETs). The NWFET used in this work was fabricated with the bottom-up process and it has a bottom-gate structure. The model includes all current conduction mechanisms of the NWFET operating at various bias conditions. The results simulated from the newly developed NWFET model reproduce a reported experimental results within a 10% error.

• Proceedings of the KIEE Conference
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• 1995.11a
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• pp.482-484
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• 1995

In designing three phase enclosure type EHV class gas insulated bus (GIB), it is essential to estimate the magnitude and the position where the maximum electric field strength occur. The improvement of insulation design can only be initiated after those informations have been obtained. In this paper, the calculated electric field strength for three phase GIB of HICO 362kV 63kA GIS is presented. The result shows that the designed insulator has enough margin compared with the design criteria.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.5
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• pp.1592-1596
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• 2010

According to the increase of the channel length with fixed width/length, characteristic curves of drain current as a function of gate bias voltage of indium gallium zinc oxide (IGZO) thin-film transistors moved to a positive direction of gate voltage, and field-effect mobility decreased. In case of fixed length and width of channel, field-effect mobility was lower and subthreshold slope was larger when drain bias voltage was higher. Due to large work function of IGZO, band bending at the junction region between IGZO channel and source/drain electrodes was expected to be in opposite direction to that between silicon and metal electrodes; this could explain the above results.

• Proceedings of the KIEE Conference
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• 1999.07a
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• pp.351-353
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• 1999

In this paper, electric field analysis of 170kV class GCB is carried out. Considering the movement of arcing contacts during circuit interruption, electric field analysis between moving and fixed contacts is performed with changing the stroke length. From analysis results, electric field stresses are high at stationary arcing contact, moving arcing contact and varies at changing nozzle shapes. Specially, the stationary arcing contact shape has an significant effect on the capacitive small current interruption and the reduction of the electric field stress at this area is important. Varying the shape of stationary arcing contact, electric field analysis is carried out and the optimal shpae of the fixed arcing contact where the electric field stress is low is designed.

• Proceeding of EDISON Challenge
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• 2016.03a
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• pp.292-294
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• 2016

이황화몰리브덴을 활용한 전계효과트랜지스터(Field Effect Transistor)는 채널 물질의 우수한 특성으로 차세대 저전력 고성능 스위치와 광전소자로 주목받고있다. Underlap 게이트 구조에서 게이트 길이(L_G), 절연체 두께(T), 절연체 상대유전율(${\varepsilon}_r$)에 따라 변화하는 소자특성을 분석하여 저전력 고성능 $MoS_2$ 전계효과트랜지스터를 위한 게이트 구조 최적화방법을 모색하였다. EDISON simulator 중 Tight-binding NEGF 기반 TMD FET 소자 성능 및 특성 해석용 S/W를 활용하여 게이트 구조에 따른 게이트 전압 - 드레인 전류 상관관계(transfer characteristic)를 얻고, Y-function method를 이용하여 채널 유효전하이동도(Effective Mobility), Sub-threshold Swing, on/off 전류비(on/off current ratio)를 추출하여 비교 분석하였다. 시뮬레이션으로 추출한 소자의 최대 채널 유효전하이동도는 $37cm^2V^{-1}s^{-1}$, on/off 전류비는 $10^4{\sim}10^5$, Sub-threshold Swing은 ~38mV/dec 수준을 보였다.

• Proceedings of the KIEE Conference
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• 1996.07b
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• pp.847-849
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• 1996

As the power demands increases, one of the most important data is inside electric field of equipment in designing of insulators ami insulated wire for EHV distribution line. So far finite element analysis method is widely used to calculate this electric field. However as the shape of insulator becomes complicated, it is difficult in producing the mesh which suitable the shape. Especially, we have many difficulty that produce dense fine mesh only where the electric field is concentrated. Therefore in this paper, we perform the each conditional analysis of electric field using the Maxwell 3D Simulator to recover this defects. And we try to analyze electric field through the conventional 2 dimensional and 3 dimensional analysis in case of salt contamination on the surface of a insulator.

• Proceedings of the KIEE Conference
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• 2003.07c
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• pp.1773-1775
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• 2003

In this Study, the insulation safety for Closing Resistor and Disconnect Switch(DS) of 362kV GIS was estimated through 3 dimensional electric field analysis. In addition, the basic study to secure the electric insulation design technique was carried out through the research on the effect of a metallic particle which is generated in the GIS. As a result of 3 dimensional electric field analysis, it was found that the insulation capability of Closing Resistor and DS of 362kV GIS is stable electrically. Also, the fundamental data to improve the insulation capability of spacer was obtained by analyzing the maximum electric field according to the attached angle of a metallic particle which is attached on the surface of a spacer.