파뢰기의 열화진단 전문가 시스템 개발에 관한 연구

길경석,김명진,한주섭 한국해양대학교 산업기술연구소 2002 연구논문집 Vol.19 No.-

This paper describes with an effect of a single- and a quadruple- lightning impulse currents on electrical characteristics of ZnO blocks, and an expert system to diagnose deterioration of arresters. In this study, an accelerated deterioration test is carried out to deduce the parameters needed for diagnosing arrester deterioration, and leakage current components are measured. Also, wave height distribution of the leakage current with the progress of arrester deterioration is analyzed. From the experimental results, the wave height distribution of the leakage current showed a conspicuous difference even in an immaterial leakage current increase. The use of wave height distribution of the leakage current in deterioration diagnostic technique makes more accurate diagnosis than the conventional method using only a leakage current value. Finally, the expert system based on the experimental reslts is developed, and the effectiveness of the system is estimated in a 18[kV] lightning arrester.

방사선 펄스 계측 및 분석시스템에 관한 연구

길경석,손원진,송재용,김일권 한국해양대학교 산업기술연구소 2002 연구논문집 Vol.19 No.-

An objection of this study is to develop a measuring circuits and a analytic system for radioactive pulses. The proposed system consists of a pulse detection units for neutrons and gamma-rays, a programmable high voltage supply unit and a digital signal processor. Gamma-ray detection circuit can count pulse up to 10,000[pps]. The pulse detection parts consists of an active integrator, a pole-zero circuit, and a 3-stage amplifier of 60[dB], and its frequency bandwidth is from 37[Hz] to 300[kHz]. Also, pulse height distribution in accordance with pulse counts is important data in analyzing radioactive pulses. In this study, A/D converter (12[bit], 100[ns] and DSP [TMS 320C31-60) are used to analyze the pulse height, and the analytic system is designed to be operated in PC-base. Radioactive pulse has superior penetration ability to all kind of materials, and it is also possible to evaluate the soundness of electrical insulation materials by analyzing the pulse counts and/or pulse height distribution.

스파크 신호검출에 의한 전기화재 예측

길경석,김일권,송재용 한국해양대학교 산업기술연구소 2002 연구논문집 Vol.19 No.-

This paper describes a technique that can predict electric fires by detecting a spark signal generated from operation of electric facilities. An electric fire lead a loss of life as well as huge property, therefore it is very important to predict an electric fire and eliminate the causes of it. Electrical spark which is ranked as majority causes of electric fires has a characterized frequency bandwidth distinguished from power frequency. In this experiment, various spark signals are simulated in a condition such as short circuit, flashover, and surface discharge. The results showed that the monitoring of spark signals can predict electric fires.

A Simulator for Potential Distribution Analysis

Gyung-Suk Kil,Hyong-Jun Gil,Dae-Won Park 대한전기학회 2012 Journal of Electrical Engineering & Technology Vol.7 No.2

This paper proposes a reduced-scale simulator that can replace numerical analytic methods for the estimation of potential distribution caused by ground faults in various grounding systems. The simulator consists of a hemispherical electrolytic tank, a three-dimensional potential probe, a grounding electrode, and a data acquisition module. The potential distribution is measured using a potentiometer with a position-tracing function when a test current flows to the grounding electrode. Using the simulator, we could clearly analyze the potential distribution for a reduced- scale model by one-eightieth of the buried depth and length of the grounding rod and grounding grid. Once both the shape of the grounding electrode and the fault current are known, the actual potential distribution can be estimated.

Study on a Partial Discharge Test for Low-Voltage Electronic Components

Gyung-Suk Kil,Dong-sik Kang,Don-ha Hwang,Jae-man Song,Jae-yong Song,Yong-ju Kim 한국물리학회 2006 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.49 No.III

This paper deals with a partial discharge (PD) test on low-voltage electronic components, which is increasingly being accepted as a non-destructive and effective dielectric test. A comparative experiment, combined with the withstand voltage test (WVT) specified in IEC standards, was carried out on low-voltage insulation transformers. The results show that the insulation degradation of the sample progresses during the WVT. However, if an apparent charge of below 1 pC is detected, the PD test can be performed within the range of 30 . 50 % of the test voltage specified in the WVT. Therefore, the PD test can be applied successfully in place of the WVT as a non-destructive test on low-voltage electronic components.e6

A Simulator for Potential Distribution Analysis

Kil, Gyung-Suk,Gil, Hyong-Jun,Park, Dae-Won The Korean Institute of Electrical Engineers 2012 Journal of Electrical Engineering & Technology Vol.7 No.2

This paper proposes a reduced-scale simulator that can replace numerical analytic methods for the estimation of potential distribution caused by ground faults in various grounding systems. The simulator consists of a hemispherical electrolytic tank, a three-dimensional potential probe, a grounding electrode, and a data acquisition module. The potential distribution is measured using a potentiometer with a position-tracing function when a test current flows to the grounding electrode. Using the simulator, we could clearly analyze the potential distribution for a reduced- scale model by one-eightieth of the buried depth and length of the grounding rod and grounding grid. Once both the shape of the grounding electrode and the fault current are known, the actual potential distribution can be estimated.

Measurement Method of the Resistive Leakage Current for Lightning Arrester Diagnosis

Kil, Gyung-Suk,Han, Ju-Seop,Song, Jae-Yong,Seo, Hwang-Dong The Korean Institute of Electrical and Electronic 2005 Transactions on Electrical and Electronic Material Vol.6 No.2

Several ways for monitoring the soundness of ZnO lightning arresters have been suggested, and all of which are based on the measurement of leakage current since it is well known that the resistive leakage current is a main indicator of arrester deterioration. In this paper, we proposed an algorithm to measure the resistive leakage current, which is quite different from the conventional method that eliminates capacitive current from the total leakage current. The proposed algorithm is based on that the magnitudes of the resistive leakage current are equal at the same applied voltage levels. To confirm the reliability of the algorithm, we fabricated a leakage current detector and designed an analysis program. Experimental results showed that the method does not need a complex circuitry and is useful to analyze the resistive leakage current.

뇌충격전류에 의한 산화아연형 피뢰기 소자의 전기적 특성과 피뢰기 열화진단 전문가 시스템

吉暻碩(Gyung-Suk Kil),韓柱燮(Joo-Sup Han),宋在鏞(Jae-Yong Song),金明珍(Myung-Jin Kim),金正培(Jung-Bae Kim),趙漢九(Han-Gu Cho) 대한전기학회 2002 전기학회논문지C Vol.51 No.4

가공배전선로의 전력설비 감시를 위한 유비쿼터스 센서

길경석(Gyung-Suk Kil),박대원(Dae-Won Perk),김일권(Il-Kwon Kim),최수연(Su-Yeon Choi),박찬영(Chan-Yong Park) 한국조명·전기설비학회 2007 조명·전기설비학회논문지 Vol.21 No.10

최근 유비쿼터스 센서네트워크 기술이 전력설비관리에 적용되어 오고 있다. 본 연구에서는 가공배전선로에서 전력용변압기와 피뢰기를 관리할 수 있는 유비쿼터스 센서의 설계 및 제작에 대해 기술하였다. 이 센서들은 8-[bit] 마이크로프로세서, IEEE 802.15.4기반 무선통신모듈과 주변 전자회로로 구성되어 있다. 변압기의 부하 및 서지전류 측정에는 1000[A]까지 포화되지 않고 선형성을 유지할 수 있도록 공심형 로고우스키 코일을 제작하여 적용하였다. 피뢰기를 흐르는 50[㎂]~1[㎃]의 미소누설전류를 측정하기 위하여 180[㎐]에서 10?의 고투자율을 갖는 영상변류기를 사용하였으며, 피뢰기 감시모듈의 -3[㏈] 주파수 대역은 12[㎐]에서 1.24[㎑]이다. Recently, ubiquitous sensor network(USN) techniques have been applied to electric power facility management. This paper dealt with the designed and fabricated ubiquitous sensors which monitor transformers and lightning arresters installed in overhead distribution systems. The sensors consist of a 8-[bit] microprocessor unit, a wireless communication module specified in IEEE 802.15.4, and associated electronics. A Rogowski coil was fabricated to measure load of transformer and surge current without saturation having good linearity up to 1000[A]. A zero-phase current transformer with a high relative permeability of 10? at 180[㎐] was used to detect small leakage current of 50[㎂]~1[㎃] flowing lightning arrester, and the frequency bandwidth of the module is ranges from 12[㎐] to l.24[㎑] at -3[㏈].

대지전계 측정을 위한 필드밀의 설계 및 제작

길경석(Gyung-Suk Kil),송재용(Jae-Yong Song),김일권(Il-Kwon Kim),권장우(Jang-Woo Kwon),안창환(Chang-Hwan-Ahn),이영근(Young-Keun Lee) 한국조명·전기설비학회 2007 조명·전기설비학회논문지 Vol.21 No.1

본 논문에서는 뇌경보시스템에 적용하기 위한 센서로 대지전계의 극성과 크기의 측정이 가능한 필드밀에 대하여 연구하였다. 회전날개를 갖는 평면 셔터형 필드밀을 설계?제작하였으며, 필드밀의 교정은 대칭적인 구조의 원형 평판전극을 수직으로 배열하고 이때 얻어지는 평등전계 내에서 수행하였다. 교정실험에서 필드밀의 감도를 0.5[V/㎸/m]로 조정하였으며, 측정 가능한 대지전계의 범위는 200[V/m]~20[㎸/m]가 된다. 교정실험 후, 건물 옥상에 필드밀을 설치하고, 뇌운에 의한 대지전계의 변화를 관측하였다. 2006년 7월 1일부터 7월 15일의 기간 중, 뇌운의 생성과 소멸, 이동에 따라 대지전계의 크기는 +2[㎸/m]~-6[㎸V/m]의 범위에서 기록되었다. 적용실험결과로 부터 제안한 필드밀은 직류 전계 측정에 충분한 성능이 있음을 확인하였다. ??A field mill capable of measuring the magnitude and polarity of electric fields at the ground level was studied to apply to a lightning warning system as a sensor. We designed and fabricated a planar-shutter type field mill with a rotating-vanes. A calibration of the field mill was performed in a vertically symmetrical arrangement which consists of two equal size parallel round plates to form a homogeneous electrical fields. The sensitivity of the field mill was adjusted at 0.5[V/㎸/m], and this covers a ranges from 200[V/m] to 20[㎸/m]. After the calibration experiment, the field mill was installed on the roof of a building to measure the changes of electric field intensity caused by thunderclouds. During the period from July 1. 2006 to July 15. 2006, the electric field intensity was recorded a ranges of +2[㎸/m]~-6[㎸/m] depending on generation, extinction and movement of thunderclouds. From the actual test on the ground, it is confirmed that the field mill has a good performance necessary for the measurement of DC electric fields.