• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.2
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• pp.237-244
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• 2016

This paper, presents the characteristics of electromagnetic fields radiated from a pole-transformer. The cylindrical cavity is used to measure electromagnetic fields radiated from a pole-transformer when partial discharge occures inside the pole-transformer. The theoretical analysis is conducted by a finite difference time domain (FDTD) method. As a result, frequency characteristics of the radiated electromagnetic waves emitted from the inside the cavity to the outside through the 1st and 2nd bushings could be observed for the configuration of the cylindrical cavity with a radiation window. The frequency characteristics of electromagnetic field are also studied according to the enclosure structure of the cylindrical cavity. To verify the theoretical analysis, computed results are compared to experimental results.

• Horticultural Science & Technology
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• v.17 no.6
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• pp.773-776
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• 1999

Effects of cacti and a few indoor plants on the protection of the harmful electromagnetic waves (ELF: extremely low frequency and VLF: very low frequency bands) radiated from the monitor of computer were investigated in indoor condition. The front screen of monitor evoked the highest amounts of electromagnetic waves as compared to other positions. Therefore, plants and other objects were placed on the front or side of monitor in order to measure electromagnetic waves. It was shown that all plants including cacti did not have any effect on the reduction of magnetic waves in both ELF and VLF, regardless of species and varieties, sizes, and dispositions. In the case of electric waves, however, there was a little reduction by cacti, depending upon several treatments mentioned before, but the measured values did not reach below values ruled by TCO (Tjatemannens Central Organization, Swedish Confederation of Professional Employees; electric field: 10 V/m and 1 V/m in ELF and VLF, respectively).

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2001.11a
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• pp.145-149
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• 2001

The most of faults in gas insulation of power facilities are caused by partial discharge. Therefore we simulated partial discharge and measured the radiated electromagnetic wave emitted from partial discharge in SF$_{6}$ gas by biconical antenna. This paper describes time delay and electric fields pulse characteristics of radiated electromagnetic waves with distance(1[m], 3[m], 5[m]) between antenna and discharge source.e.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.18 no.5
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• pp.90-95
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• 2004

This paper simulated partial discharge caused by 22.9[kV] power cable using XLPE(Peroxide Crosslinkable Polyethylene) insulation having the outside damage. As one of the insulation diagnostic method a radiated electromagnetic waves were measured by an UHF method using a BiconiLog antenna(EMCO-3142) and a spectrum analyzer used to measure EMI, EMC. From results of this study, It was confirmed that discharge Ogress were possible to be estimated by the proposed method.

• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.1862-1864
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• 2000

Recently diagnostic techniques have been investigated to detect a partial discharge(PD) associated with a dielectric material defect in a high-voltage electrical apparatus. Among the PD measuring method, detecting electromagnetic wave generated by PD is one of the most effective method because PD radiates wide frequency of electromagnetic wave up to UHF. From the above points of view, we have investigated the polarization and distance characteristics of electromagnetic wave radiated by an insertion of solid insulators between needle-plane electrodes in the air. According to the magnitude of applied voltage, the frequency spectrum of radiated electromagnetic waves were increased about under 100(MHz), compared with background noise. The electromagnetic wave magnitude is attenuated about 4$\sim$7.6[dB] at the point 3[m] away from PD.

• Proceedings of the KIEE Conference
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• 2001.07c
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• pp.1774-1776
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• 2001

The most of faults in gas insulation of power facilities are caused by partial discharge. Therefore we simulated partial discharge and measured the radiated electromagnetic wave emitted from partial discharge in the $SF_6$ gas by biconical antenna. This paper describes time delay characteristics of radiated electromagnetic waves with distance between antenna and discharge source.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.19 no.2
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• pp.69-76
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• 2005

In this paper partial discharge were simulated by insulation particle which could be easy accumulated charge and concentrated electric field in the model GIS. In this times this paper measured and analyzed the radiated electromagnetic waves by using spectrum analyzer and antenna$(30\~2000(MHz))$ for measurement of$ EMI{\cdot}EMC$ in accordance with occurrence and propagation of partial discharge. This paper suggested the other method of detecting and estimating of partial discharge for insulation diagnosis of GIS being insulation particle by measurement and analysis of radiated electromagnetic waves. From results of this study, it was confirmed that if the suggested method should be used for the diagnosis of insulation in the model GIS being insulation particle, detecting partial discharge and estimating discharge propagation will be possible.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.41-45
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• 2010

In this paper, we analyzed the frequency spectrum of radiated electromagnetic waves generated by series arc- and corona- discharges as a basic study to develop an online diagnostic technique for power facilities installed inside switchboards. To simulate corona and series arc discharges, an arc generator specified in UL1699 and a corona generator were fabricated. The experiment was carried out in an electromagnetic shielding room, and the measurement system consists of an Ultra Log Antenna and an EMI Test Receiver. The frequency spectrum exists in ranges from 30 to 500 [MHz] for series arc discharge and 30 [MHz] to 2 [GHz] depending on defects for corona discharge. The peak frequency of series arc discharge and corona were 40 [MHz], 80 [MHz] and 35 [MHz]~160 [MHz], respectively.

• Proceedings of the KIEE Conference
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• 2002.07c
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• pp.1748-1750
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• 2002

Partial discharge is attendant physical phenomenon on electromagnetic, sounds, lightning and mechanical vibration. In this paper, we simulated GIS and measured the radiated electromagnetic wave emitted from partial discharge in $SF_6$ gas using antenna(30[MHz] ${\sim}$ 2[GHz]) and spectrum analyzer. This paper describes characteristics of radiated electromagnetic waves with distance 1 [m] between antenna and discharge source.

• Journal of IKEEE
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• v.17 no.1
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• pp.10-15
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• 2013

This paper, we analyzed that the measured data of the radiated power spectrum of electromagnetic waves of the normal spark ignition system and the spark ignition system with feed through type ceramic condenser. The results show that the strength of power spectrum radiated from the system with feed through type ceramic condenser is weaker than the normal system, and the density of power spectrum radiated from the system with feed through type ceramic condenser is smaller than the normal system. From these results, the feed through type ceramic condenser can reduce the electromagnetic waves radiating from the spark ignition system which is the spurious emission, and it can be concluded that the ignition coil of the spark ignition system generating high voltage pulse is equivalent to the radio frequency oscillator which is oscillating high frequency from a electronic point of view.