• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.8
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• pp.1397-1404
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• 2007

It is important to measure the resistive component separately from the total leakage current at power distribution line. It is because electric disasters such as electric shock and fire are caused mainly by the resistive component of the total leakage current. In this paper, a new theory for measuring the resistive component separately from the total leakage current is suggested, and is embodied to an actual circuit using operational amplifiers, analog switch and R-C low pass filter. Through experiments for various cases containing both the resistive and capacitive leakage currents, the suggested algorithm is confirmed to be able to measure the resistive leakage current within 4.1% of error even when the capacitive leakage current is much bigger than the resistive one. The suggested method is expected to lower the total cost because it can be realized using simple and cheap devices, and implies the measuring time can be possibly reduced because the resistive leakage current is computed exactly from the signals during only a half period of power voltage.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.917-918
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• 2007

The former earth leakage breaker is operating by total leakage current which is the vector-sum of resistive leakage current and capacitive leakage current. However, the electric disaster like the electric shock and fire is caused mainly by resistive leakage current. Therefore, the earth leakage breaker is ideal when it is operating by resistive leakage current. In this paper, the theory for finding the component of resistive leakage current from total leakage current is suggested and it is embodied to actual circuit. The resistive leakage current can be found by integrating the total leakage current during half cycle of line voltage. Thus, we can simply find resistive leakage current by using OP-AMP integrators, and we can confirm that the resistive leakage current is computed exactly from total leakage current obtained by resistive leakage current and capacitive leakage current. The results that the earth leakage breaker is operating within regular interrupt time are verified when the former earth leakage breaker's controller circuit is replaced by the proposed controller circuit.

• Progress in Superconductivity and Cryogenics
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• v.5 no.1
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• pp.60-65
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• 2003

An effective modeling and simulation scheme of a resistive type Superconducting fault Current Limiter (SFCL) using PSCAD/EMTDC is proposed in this paper. In case of High Temperature Superconducting (HTS) resistive type fault current limiter current limiting is implemented by the ultra-fast transition characteristics from the superconducting (non-resistive) state to the normal (resistive) state by overstepping the critical current density. The states can generally be divided into three sub-states: the superconducting state the quench state and the recovery state respectively. In order to provide alternative application schemes of a resistive type SFCL, an effective modeling and simulation method of the SFCL is necessary. For that purpose, in this study, an actual experiment based component model is developed and applied for the simulation of the real resistive type SFCL using PSCAD/EMTDC. The proposed simulation scheme can be implemented to the grid system readily under various system conditions including sort of faults and the system capacity as well. The simulation results demonstrate the effectiveness of the proposed model and simulation scheme.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.42 no.5 s.335
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• pp.61-68
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• 2005

In this paper, low conversion loss 94 GHz MIMIC resistive mixer was designed and fabricated. The $0.1{\mu}m$ InGaAs/InAlAs/GaAs Metamorphic HEMT, which is applicable to MIMIC's, was fabricated. The DC characteristics of MHEMT are 665 mA/mm of drain current density, 691 mS/mm of maximum transconductance. The current gain cut-off frequency(fT) is 189 GHz and the maximum oscillation frequency(fmax) is 334 GHz. A 94 GHz resistive mixer was fabricated using $0.1{\mu}m$ MHEMT MIMIC process. From the measurement, the conversion loss of the 94 GHz resistive mixer was 8.2 dB at an LO power of 10 dBm. P1 dB(1 dB compression point) of input and output were 9 dBm and 0 dBm, respectively. LO-RF isolations of resistive mixer was obtained 15.6 dB at 94.03 GHz. We obtained in this study a lower conversion loss compared to some other resistive mixers in W-band frequencies.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.2
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• pp.198-207
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• 2008

The conventional Residual Current Protective Devices(RCD, or earth leakage circuit breaker, ELB) operates depending on the total leakage current which is the vector-sum of resistive and capacitive components of a leakage current. However, the electric disaster such as electric shock or fire is mainly caused by the resistive component. Therefore, in this view point, the RCD is more realistic when it operates by the resistive component of the leakage current. In this paper, a new algorithm for measuring the resistive leakage current from the total leakage current is suggested, and is realized to an actual circuit. According to the suggested algorithm, the resistive component of the leakage current can be found by integrating the total leakage current over only a half cycle of the line voltage, and it is realized by using analog switches and resettable integrators. It is confirmed through experiments that the suggested algorithm detects, within maximum average error of 6.74%, the resistive leakage current from the total leakage current, and the RCD employing the suggested algorithm brakes the circuit within the regular interrupt time(30msec).

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.52 no.10
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• pp.469-475
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• 2003

Resistive leakage current flowing ZnO blocks increases with its ages, which is an important indicator of arrester deterioration. However, a complicated circuitry is essential to measure the resistive leakage current included in the total leakage current, and the difficult handling of the measurement makes few applications to the fields. In this paper, we propose a resistive leakage current measurement device which is composed of a current detection circuit and an analysis program operated on a microprocessor. The device samples the input leakage current waveform digitally, and discriminate the zero-cross and the peak point of the waveform to analyze the current amplitude vs. phase. The capacitive leakage current is then eliminated from the total leakage current by using an algorithm to extract the resistive leakage current only. Also, the device can be operated automatically and manually to analyze the resistive leakage current even when the leakage current waveform is distorted due to various types of arrester deterioration. To estimate the performance of the device, we carried out a test on ZnO blocks and lightning arresters. From the results, it is confirmed that the device could analyze most parameters needed for the arrester diagnostics such as total leakage current. resistive leakage current, and the $3^rd$ harmonic leakage current.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.10
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• pp.1672-1681
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• 2016

This paper proposes a wireless parallel operation method of three-phase modular UPS inverter using resistive droop control. Furthermore, it applies a virtual resistor to droop control so that the output impedance of UPS inverter gets closer to resistive. It makes resistive droop control effective. The simulation using PSIM was performed in order to verify the validity of proposed algorithm. After consisting two-parallel system with three-phase modular UPS inverter, the experiment according to resistive load was conducted. It demonstrated the performance of current sharing and power sharing.

• ETRI Journal
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• v.29 no.1
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• pp.59-69
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• 2007

We designed and fabricated a vision chip for edge detection with a $160{\times}120$ pixel array by using 0.35 ${\mu}m$ standard complementary metal-oxide-semiconductor (CMOS) technology. The designed vision chip is based on a retinal structure with a resistive network to improve the speed of operation. To improve the quality of final edge images, we applied a saturating resistive circuit to the resistive network. The light-adaptation mechanism of the edge detection circuit was quantitatively analyzed using a simple model of the saturating resistive element. To verify improvement, we compared the simulation results of the proposed circuit to the results of previous circuits.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.13 no.3
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• pp.247-253
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• 2000

We evaluated the electric properties of Bi-2223 jointed tapes processed by both resistive-and superconducting-joint methods. For resistive-joint. filler materials of wood metal Pb/Sn. In and silver paste were used whereas for superconductive-joint lap joint method was used. In the resistive joint tape. critical transport property(CCR) n-value and contact resistance were observed to be in the range of 10-85% 1-8,9. and 0.71x10$\^$-6/-0.13x10$\^$-6/Ω, respectively. depending on their filler materials. Specifically it is believed that the electrical properties of resistive joint tape are significantly related to the resistivity of filler materials. On the other hand the CCR of superconductin joint type was varied 55 to 85% with uniaxial pressure probably due to the irregular microstructure in the transition region.

• The Journal of the Korea institute of electronic communication sciences
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• v.8 no.3
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• pp.447-452
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• 2013

In this paper, the leakage current detection and auto shut-off module for a concent has been developed. Existing leakage current detection modules are detecting resistive leakage current, using a resistive leakage current detection chip but the proposed leakage current detection module separates and detects resistive leakage current in the synthesis leakage current by only programming in a power processor MCU(MSP430). The module implemented by proposed method has early detection and auto shut-off feature at more than resistive leakage current 5mA, and has the advantage of easily adjusting resistive leakage current less or more than 5mA, because of resistive leakage current detection function being implemented by a program in MCU.