• Proceedings of the KIEE Conference
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• 1991.07a
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• pp.171-173
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• 1991

the poly silicon film was deposited by APCVD. and then the deposition mechanism and electrical characteristics was investigated for that film. The grain phase, the deposition rate, and the etch characteristics were evaluated according to the deposition conditions. The criteria temperature of surface morphology state was $730^{\circ}C {\sim}780^{\circ}C$ between the mirror phase grain and the powder phase grain.

• Proceedings of the KIEE Conference
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• 2001.07b
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• pp.596-598
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• 2001

This paper presents an analysis of the characteristics in switched reluctance motor (SRM). 2D finite element method (FEM) considering the iron saturation and the actual switching circuit of the SRM drive is applied for the dynamic analysis. The influence of the rotor shape on the radial force and torque ripple is investigated and the optimal shape of rotor pole is proposed to enhance the torque. The radial force characteristics acting on the surface of teeth is investigated by using the Maxwell's magnetic stress tensor method.

• KIEE International Transactions on Electrophysics and Applications
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• v.3C no.4
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• pp.146-154
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• 2003

This paper describes various characteristics of the new compounds for cable jackets and model cables advanced in waterproof performance in order to essentially solve the problems of underground (URD) distribution class power cable failures. Several compounds were manufactured by the inclusion of additives to base resins available in Korea and tested for basic property, mechanical and electrical characteristics. Two model cables were created by using the compounds determined in the test as being the most appropriate for new structured model cable jacket material. The waterproof performance and mechanical strength of the new cable jackets were verified by applicable tests. As a result, MDPE and LLDPE compounds were superior as cable jackets in both mechanical and electrical characteristic aspects when compared with conventional PVC. In addition, the model cables composed of the new compounds based on MDPE showed good quality results in the water permeability test.

• Proceedings of the KIEE Conference
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• 1998.07e
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• pp.1746-1748
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• 1998

In this paper, the relation between the increment of metallic content such as copper(Cu) and iron(Fe) according to degradation of pole-transformer oil and change of electrical characteristics according to increment of metallic content was studied. As the result, electrical characteristics was decrease according to increment of metallic content, especially copper content, and the trend of T.C.G(Total Carbonic Gas) agreed with the trend of copper content.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.05a
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• pp.184-186
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• 2002

In this paper, we studies EMTP analysis and characteristics of critical voltage of pulse corona and load impedance on variable electrode length. To obtain a stable pulse voltage, we designed a compact pulse generator switched MOSFET and tested their characteristics by adjusting electrode length and pulse repetition. As a result, critical voltage of pulse corona and load impedance on increasing electrode length were decreased. These results indicate we can control critical voltage of pulse corona and suppress arc discharging between two electrodes.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.68 no.1
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• pp.36-43
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• 2019

In this paper, the characteristics of the coaxial magnetic gear according to the shape of the same gear ratio are analyzed using the two - dimensional finite element analysis. The rotor shape is SMCMG, CPCMG and RCMG. After this we analyzed the characteristics according to three shapes. Also, the amount of permanent magnet used in each shape was compared. Next, characteristics analysis of the magnetic gear according to the shape at the same torque was performed. And the total weight and efficiency of the magnetic gears were compared and verified.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.11
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• pp.1566-1570
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• 2013

In this paper, we analyzed the electric characteristics of the OLEDs device of which anode ITO has been treated with the oxygen plasma. We fabricated the basic three-layer structure (ITO / AF / $Alq_3$ / $Cs_2CO_3$ / Al) device, analyzed how the oxygen plasma treatments of the ITO surface affects to the electrical characteristics of OLEDs. We also produced a four-layer structure device (ITO / AF / TPD / $Alq_3$ / $Cs_2CO_3$ / Al) with the oxygen plasma treatment. From the comparative analysis to the devices, we confirmed following results. The three-layer structure OLEDs device with oxygen plasma treatment has better characteristics than the device without the treatments; maximum luminance, luminous efficiency, and external quantum efficiency are improved approximately 151 [%], 126 [%], and 175[%], respectively. Also, the electric characteristics of the four-layer structure device with oxygen plasma treatment are improved comparing to the characteristics of the three-layer structure device with oxygen plasma treatment; maximum luminance, luminous efficiency, and external quantum efficiency are improved approximately 144 [%], 115 [%], and 124[%], respectively.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.3
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• pp.259-266
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• 2004

In this paper. a new two types of EST(Emitter Switched Thyristor) structures are proposed to improve the electrical characteristics including the current saturation capability. Besides, the two dimensional numerical simulations were carried out using MEDICI to verify the validity of the device and examine the electrical characteristics. First, a vortical trench electrode EST device is proposed to improve snap-back effect and its blocking voltage. Second, a dual trench gate EST device is proposed to obtain high voltage current saturation characteristics and high blocking voltage and to eliminate snap-back effect. The two proposed devices have superior electrical characteristics when compared to conventional devices. In the vertical trench electrode EST, the snap-back effect is considerably improved by using the vertical trench gate and cathode electrode and the blocking voltage is one times better than that of the conventional EST. And in the dual trench gate EST, the snap-back effect is completely removed by using the series turn-on and turn-off MOSFET and the blocking voltage is one times better than that of the conventional EST. Especially current saturation capability is three times better than that of the other EST.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.30 no.2
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• pp.101-105
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• 2017

In this paper, the magnetization characteristics and the stored energy of magnetically coupled superconducting fault current limiter (SFCL)s using single and double high-Tc superconducting (HTSC) elements were compared. To analyze the magnetization characteristics and the stored energy, the magnetizing current and the flux linkage, which were derived from the electrical equivalent circuit of the SFCL using single and double HTSC elements, were calculated from the voltages and the current measured in the short-circuit tests. Through the comparative analysis on the magnetization characteristics and the stored energy for SFCL using sing and double HTSC elements, the magnetically coupled SFCL using double HTSC elements was shown to be more effective than the SFCL using single HTSC element from the point of view of the magnetic saturation.

• Journal of Electrical Engineering and Technology
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• v.13 no.3
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• pp.1398-1406
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• 2018

Owing to the consistent increase in accurate analysis issue for energy consumption of the AC electric railway systems, there is controversy about the adequacy of the present watt-hour metering configuration. Due to the unusual load characteristics and facilities, the discussions have not been active. Therefore, in order to achieve more accurate watt-hour metering for AC electric railway system, this paper proposes numerical formulas for watt-hour metering that reflects the highly-varying characteristics of the railway load and the structural characteristics of the Scott transformer. The proposed formulas have been verified by comparison with site-measured data, and a more suitable metering configuration for AC railway system has been proposed.