• Proceedings of the IEEK Conference
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• 2003.07b
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• pp.779-782
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• 2003

The theoretical and experimental current-voltage characteristics of Erbium silicided n-type Schottky barrier tunneling transistors (SBTTs) are discussed. The theoretical drain current to drain voltage characteristics show good correspondence and the extracted Schottky barrier height is 0.24 eV. The experimentally manufactured n-type SBTTs with 60 nm gate lengths show typical transistor behaviors in drain current to drain voltage characteristics. The drain current on/off ratio is about 10$^{5}$ at low drain voltage regime in drain current to gate voltage characteristics.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2008.10a
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• pp.281-283
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• 2008

The superconducting fault current limiter (SFCL) using magnetic coupling of two coils with series connection, which was suggested by us, has the merit to increase the operational current and the limiting impedance of the SFCL through the adjustment of the inductance ratio and the winding direction of two coils. In addition, the recovery characteristics of the SFCL is affected by the winding direction of two coils as well as two coils' inductance ratio. In this paper, the fault current limiting and recovery characteristics of a SFCL using magnetic coupling of two coils with series connection were analyzed. Through the analysis based on the experimental results, the recovery characteristics and the current limiting characteristics of the SFCL were confirmed to be improved more in case of the additive polarity winding.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.54 no.9
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• pp.391-396
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• 2005

In this paper the modeling of interrupting characteristics of a high voltage current limiting fuse to be used in a power distribution system is introduced. In order to reduce the level of energy which can be absorbed by equipment during fault current flow, a high voltage current limiting fuse can generate a high voltage at the fuse terminals. Consequently it is necessary to model and analyze precisely the voltage and current variation during a CL fuse action. The characteristics of CL fuse operation modeled by electrical components have been performed with less than 6 [$\%$] errors. So the fuse designer or manufacturer can estimate the characteristics of CL fuse operation by using this modeling. The Electro Magnetic Transient Program (EMTP) is used to develop the modeling.

• Proceedings of the KIEE Conference
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• 1991.07a
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• pp.587-590
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• 1991

It is general to make the circuit analysis of current-fed type inverter driven by current source with rippleless input under the assumption of infinite induction Ld in direct current reactor(DCL). This paper focusing on the fact that Ld has bounded value in real circuit, examines operating characteristics by analysis of static state characteristics of current type inverter driven by voltage source and compares it with the operating characteristics of the circuit driven by current source.

• Proceedings of the KIEE Conference
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• 2005.11b
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• pp.368-370
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• 2005

Superconducting fault current limiter (SFCL) provides the effect such as enhancement in power system reliability due to limiting fault current in a few miliseconds. The flux-lock type SFCL among various type SFCLs consists of two coils wound on the same iron core and a component using the YBCO thin film. In the SFCL, operation characteristics can be controlled by adjusting the inductances and the winding directions of the coils. In this paper, we investigated the various fault current limiting characteristics according to the voltage level. To analyze the current limiting performance, we compared operational characteristics on the subtractive polarity winding direction on in case of open-loop iron core.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.4
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• pp.16-23
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• 2020

An electric vehicle operates at high currents and requires real-time monitoring of the entire system for ensuring efficiency and safety of the vehicle. Current sensors are applied to drive the motors, inverters, and battery control systems, and are the key components to ensure constant monitoring of the magnitude and waveforms of the operating current. In this study, a heat treatment process condition to influence the performance of Permalloy current sensors was developed; the correlation between the output capacity, low-temperature characteristics, and high-temperature characteristics of the current sensor was studied; and the process was optimized to meet the required output accuracy and temperature characteristics.

• Progress in Superconductivity and Cryogenics
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• v.4 no.1
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• pp.55-60
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• 2002

$100 A/mm^2$ class Bi-2223 tapes have recently become commercially available. Some important characteristics of the tapes, e .g. critical current, ac loss, characteristics at joint, fault current characteristics, are required for an application such as a power cable or a power transformer. In this paper they have been investigated experimentally. The results indicate that the self-field loss of the high current density tapes is not negligible, compared to resistive loss in a copper wire for the same currents. In a cable, the self-field loss for relatively large currents is much larger than the magnetization loss due to an external field. But in a transformer, the magnetization loss is dominant, compared to the self-field loss. Finally the fault current characteristics show that the high current density tapes are never safe from burn-out even for fault currents with a few cycles.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.10
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• pp.1034-1040
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• 2004

The latch-up current and switching characteristics of MOS-Controlled Thyristor(MCT) are studied with variation of the channel length and impurity concentration. The proposed MCT power device has the lateral structure and P-epitaxial layer in substrate. Two dimensional MEDICI simulator is used to study the latch-up current and forward voltage-drop from the characteristics of I-V and the switching characteristics with variation of impurity concentration. The channel length and impurity concentration of the proposed MCT power device show the strong affect on the anode current and turn-off time. The increase of impurity concentration in P and N channels is found to give the increase of latch-up current and forward voltage-drop.

• Proceedings of the Korea Society for Industrial Systems Conference
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• 1997.11a
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• pp.451-462
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• 1997

A 2-dimensional numerical analysis is presented for thermal-electron heat conduction effects upon the electron transport and the drain current-voltage characteristics of submicron GaAs MESFETs, based on the use of a nonstationary hydrodynamic transport model. It is shown that for submicron GaAs MESFETs, electron heat conduction effects are significant on their internal electronic properties and also drain current-voltage characteristics. Due to electron heat conduction effects, the electron energy is greatly one-djmensionalized over the entire device region. Also, the drain current decreases continuously with increasing thermal conductivity in the saturation region of large drain voltages above 1 V. However, the opposite trend is observed in the linear region of small drain voltages below 1 V. Accordingly, for a large thermal conductivity, negative differential resistance drain current characteristics are observed with a pronounced peak of current at the drain voltage of 1 V. On the contrary, for zero thermal conductivity, a Gunn oscillation characteristic is observed at drain voltages above 2 V under a zero gate bias condition.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.51 no.2
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• pp.62-67
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• 2002

This paper provides the results of accelerated aging test of 18kV ZnO lightning arresters to investigate the leakage current characteristics. It was impossible to establish the replacement criterion for field operating lightning arrester because conventional aging test was only focused on the aging of ZnO elements. In general, it is possible to replace the aged arresters before the failure in the field using the leakage current measurement because it must be increased by the aging. But we can not use the method because we don't know the characteristics of the installed lightning arresters. Therefore in this paper we applied operating voltage and accelerating cycle which consists of temperature and humidity to the arresters. Then we measured the variation of total and resistive leakage current and found out the characteristics of the acted lightning arresters.