• 한국조명전기설비학회지:조명전기설비
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• 제9권6호
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• pp.23-31
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• 1995

As a study on electromagnetic radiation emission from the neon signs, this paper has investigated the characteristics of frequency bands and spectra intensities under the operations of the sign's OFF, ON/OFF and continuous ON states. Also we have studied the above characteristics when a distance between the sign and the antenna is varied. All data were obtained in the range of 0.1∼1,000[MHz] by using spectrum analyzer along with the loop, biconical and log periodic antenna. As the result, we found that the radiated electromagnetic waves of the sign at continuous ON states were measured only in the range of 30∼400[MHz] but those of the sign at ON/OFF states were appeared widely in the range of 2∼1,000[MHz].

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 C
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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.

• 조명전기설비학회논문지
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• 제16권4호
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• pp.73-79
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• 2002

본 논문는 공기중 교류전압원을 이용하여 3종류의 전극부(침대평판전극, 평판대평판전극 및 구대평판전극부)에서 방전시 방사되는 방사전자파를 측정하고, 그 스펙트럼의 특이한 패턴을 나타냈다. 방사전자파의 측정은 스펙트럼분석기와 바이코니칼 안테나를 사용하여 VHF(30~230[MHz])대역에서 측정하였다. 방전개시전압영역일 때, 침대평판전극부인 경우에는 주파수 45, 70, 80[MHz] 대역에서, 평판대평판전극과 구대평판전극부인 경우에는 주파수40[MHz]에서 높은 전계강도를 나타내었다. 그러나 절연파괴전압영역일 때, 방사전자파의 주파수 스펙트럼분포는 전극의 형태에 따라 측정주파수 영역에서 차이를 나타내었다.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제51권10호
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• pp.492-499
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• 2002

This paper presents the method for an estimation of discharge current waveform in short gap discharge by radiated electromagnetic fields. The method of current waveform estimation is to use the one antenna method (single field method) with a measured electric or magnetic field at given field point by a time domain antenna. In order to verify the availability of the estimation theory, the discharge current waveform estimation was performed by one antenna methods using the measured electric fields of Wilson & Ma and compared with experiments. In addition diagnosis technique for power equipments is able to prevent from large accidents by finding signs of tile accidents before they happen. From the results of the estimation of discharge current, we have a possibility for the application of insulation diagnosis technique for power equipments using S$F_6$ gas. From this point of view, this paper simulated discharge progress and partial discharge by using needle-plan electrodes system in S$F_6$, studied the distribution of frequency spectrum of the radiated electromagnetic waves using a biconical antenna and a spectrum analyzer. From the experimental results of this study, according to the consideration of the mutual relation between frequency spectrum of the radiated electromagnetic waves and discharge progress, it was confirmed that detecting Partial discharge and estimating discharge progress in S$F_6$ could be Possible.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 추계학술대회 논문집 전기물성,응용부문
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• pp.219-223
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• 2001

In this paper, electromagnetic waves were measured in accordance with propagating the discharge when positive and negative DC high voltage was applied to needle-plane electrdes and plane-plane electrdes that solid dielectric was inserted between the electrodes. The radiated electromagnetic waves were investigated in bandwidth of VHF($30{\sim}230$[MHz]) using an biconical antenna. In needle-plane electrodes high electric field intensity is shown in both frequency band of 90(MHz) and 170[MHz], and gradually decreasing characteric is appeared at high frequency band. However high electric field intensity is shown in both 80[MHz] and 140[MHz] in case of plane-plane electrodes configuration. And over 150[MHz] frequency band, rapidly decreasing characteristic is shown. Moreover, electric field intensity of positive DC is about $5{\sim}10$[dB] higher than negative DC.

• 한국전자파학회논문지
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• 제16권11호
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• pp.1086-1098
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• 2005

UWB 통신용으로 소형 광대역 안테나의 두 가지 형태를 제안하고자 한다. 하나는 회로 기판 위에 쉽게 장착되고 동축 선로로 급전되는 소형 바이코니컬 형태이며, 다른 하나는 CPW로 급전되는 보우 타이 형태이다. 일반적으로 후자 형태는 전자보다 주파수 대역폭이 더 좁다. 그러나 CPW의 중심 도체 선로에 특성 임피던스가 더 높은 좁은 선로로 대치해줌으로써 일렬의 유도성 성분을 도입한다면 보우 타이 안테나도 바이코니컬 안테나처럼 비교될만한 대역폭을 확장할 수 있다. 이런 유도성 성분은 소형 보우 타이 안테나의 용량성 성분을 상쇄하는 중요한 역할을 하며, 광대역 임피턴스 매칭을 가능하게 만든다. 설계 검증을 위해 소형 평면 보우 타이 안테나를 제작 및 실험하였고, 반사 손실의 측정 결과는 계산 결과와 거의 일치하였으며, 방사 패턴도 측정하여 제시하였다.

• 한국초전도저온공학회:학술대회논문집
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• 한국초전도저온공학회 2002년도 학술대회 논문집
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• pp.5-9
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• 2002

In this paper, a relationship between AC discharge progress and the radiated electromagnetic waves was investigated by measuring electromagnetic waves using a biconical antenna and a spectrum analyzer at the atmospheric pressure in L$N_{2}$ . From the results of this study, according to the consideration of the mutual relation between frequency spectrum of the radiated electromagnetic waves and discharge progress, it was confirmed that detecting partial discharge and estimating discharge progress can be possible. It Is considered that these results obtained from this investigation may be used as the fundamental data for diagnosis and prediction of insulation on superconducting and cryogenic power equipments.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 추계학술대회 논문집 학회본부 C
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• pp.956-958
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• 1998

In this study, a relationship between partial discharge and the radiated electromagnetic waves is investigated by measuring electromagnetic waves using a biconical antenna and a spectrum analyzer. The patterns of frequency spectrum of radiated electromagnetic waves measured at the atmospheric pressure in Liquid Nitrogen($LN_2$) during the partial discharges in nonuniform electric field depend on positive DC power. From these points of view. it is considered that these results obtained from this investigation may be used as fundamental data for diagnosis and prediction of insulation on the equipments of superconducting and cryogenic applications.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제52권3호
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• pp.123-129
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• 2003

In this paper, a relationship between AC discharge progress and the radiated electromagnetic waves was investigated by measuring electromagnetic waves using a biconical antenna and a spectrum analyzer. The frequency spectrum of the radiated electromagnetic waves were measured at the atmospheric pressure in liquid nitrogen($LN_2$) during partial discharges progressed by AC high voltage in nonuniform electric field. Front the results of this study, a new method was introduced for measurement and analysis of the radiated electromagnetic waves with discharge progress in $LN_2$ Besides. according to the consideration of the mutual relation between frequency spectrum of the radiated electromagnetic waves and discharge progress, it was confirmed that detecting partial discharge and estimating discharge progress could be possible. It is considered that these results obtained from this investigation may be used as fundamental data for diagnosis and prediction of electric insulations about superconducting and cryogenic power equipments.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 1999년도 학술대회논문집-국제 전기방전 및 플라즈마 심포지엄 Proceedings of 1999 KIIEE Annual Conference-International Symposium of Electrical Discharge and Plasma
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• pp.285-289
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• 1999

Insulation diagnosis techniques of power equipments for the stable power supply and prevention from accidents are of high importance. Diagnosis techniques is able to prevent from large accidents before they happen by finding signs of the accidents. From this point of view, this paper simulated discharge progress and partial discharge using needle-plan electrode system in air, studied the distribution of frequency spectrum of the radiated electromagnetic waves using biconical antenna and spectrum analyzer. From results of this study, the new method was introduced for measurement and analyzation of the radiated electromagnetic waves in accordance with discharge progress in air, Besides, according to the consideration of the mutual relation between frequency spectrum of the radiated electromagnetic waves and discharge progress, it was confirmed that detecting partial discharge and estimating discharge progress were possible.