• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 E
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• pp.1740-1742
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• 1998

This paper describes the technique of deterioration diagnosis for ZnO element. Due to the non-linear resistance of ZnO block, the total leakage current contains harmonics when arrester deteriorated. The most significant harmonics is the 3rd order component. So, it can be used as an indicator of the arrester condition. An iron core, which has a very high relative permeability, is used for increasing detection sensitivity and the 3th order harmonics of leakage current was detected by band-pass circuit. And we have verified the reliability and performance of the sensing device through several laboratory tests.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제52권12호
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• pp.562-567
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• 2003

Lightning arresters are deteriorated by repetition of protective operation against overvoltages or impulse currents in environments of its use. If a deteriorated arrester is left in power lines, it can lead to an accident such as a line to ground fault even in a normal system. Therefore, it is necessary to eliminate the deteriorated arrester in advance by checking the soundness of arresters on a regular basis, and to ensure the reliability of power systems by preventing accidents. Various deterioration diagnostic techniques and devices are suggested, and most of which measure leakage current components as an indicator of arrester ageing. However, the techniques based on the magnitude of leakage current measure simply RMS or peak value of leakage current components and do not provide detailed information needed in the diagnosis. In this study, we found that the wave height distributions of the total leakage currents are remarkably changed or a new wave height are produced with the progress of arrester deterioration. To propose a new technique for the diagnosis, we designed a leakage current detection unit and an analysis program which can measure leakage current magnitudes and analyze wave height distributions. From the experimental results, we confirmed that the proposed technique by analyzing the wave height distribution can simply diagnose the mode of defects such as a partial damage and an existence of punctures in arresters as well as deterioration of arresters.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 C
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• pp.1082-1084
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• 1998

In this paper, we developed a diagnosis device for ZnO arrester to detect on-line leakage current and acquire data from the power distribution system. The arrester is important power equipment used in power transmission and distribution systems to protect the generator and the main transformer from surge and overvoltage. First of all we developed a diagnosis device for ZnO arrester leakage current. And then we detect the total leakage current by the developed device without disconnecting the arrester ground wire and analysis the 3rd order harmonic by Fast Fourier Transform(FFT) to diagnose the ZnO arrester deterioration. With measuring the total current and the resistive current of power distribution system in operation, we analysis the trend of resistive current component in the total leakage current. We expect the result will be promote the method to protect electrical utility and customer from accident.

• 한국철도학회논문집
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• 제7권4호
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• pp.307-311
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• 2004

Arresters are the best protective device on electrical power systems against transient overvoltages generated by lightning and/or switching operation. Nonetheless, arresters are deteriorated by absorption of moisture in the environments of its use, repetition in the protective operation to overvoltages, and some defects at manufacturing. It is therefore important to estimate the electrical characteristic changes of ZnO blocks. In this paper, an accelerated ageing test by a standard lightning impulse current was carried out to extract parameters needed for arrester diagnosis, and leakage current components were measured. Total energy applied to the ZnO blocks at each time is about 1,050[J] in 8/20[${\mu}\textrm{s}$] impulse current. From the experimental results, we proposed electrical parameters and leakage current level to diagnose arrester soundness.

• 전기학회논문지
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• 제63권2호
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• pp.313-318
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• 2014

In the last couple of decades industrialization and technological development has not only increase in the scale of electrical facilities and it has become more and more complicated and diversified. Furthermore, fires in the electrical transformers, like those that have knocked out power in the country in the past years, are likely to become more common as utility systems begin to show their age. The importance of preventing electrical accidents can never be overemphasized and for this reason, supply of on-line diagnosis system combining information and communication technology(ICT) for the customer's electrical facilities has been increasing recently. The major advantage of on-line diagnosis system is that the device's potential problems could be detected early before a serious deterioration or breakdown occurs. In this paper, We estimated the benefit from the investment in the right of present value of sales, success rate of commercialization regarding R&D investment for development and commercialization of on-line diagnosis technology targeting customer electrical facilities. As a result, the net value added of 29.7 billion won and the increased profit by roughly 7.52 precent are expected.

• 조명전기설비학회논문지
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• 제14권6호
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• pp.85-92
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• 2000

본 논문에서는 간이 열화 측정 탑촉자를 갖고 무선 데이터 통신의 이용으로 배전용 변압키(주양/지상)을 감사 진단할 수 있는 장치를 개발하였다. 개발한 장치는 크게 건이 열화 측정 탐촉자, 유위 측청 정치, 열화 측정 장치 및 송.수신부(무선 자료 수집 정치, 원격 제여 장치)로 구성되어 았다. 제안한 장치의 효용성 빛 적용성을 검증 하기 위해서 기존의 정밀급 계측 장치와의 비교.분석 실험을 수행하였으며, 그 상관 관계를 검토한 결과, 상대적인 선형 관계가 있음을 확인하였다. 띠라서 본 논문에서 제안한 감시 및 진단 장치를 주상/지상 변압기에 설치하면 간편하면서도 경제적으로 수많은 배전용 변압기의 신뢰성 있는 감시 진단이 가능하리라 기대된다.

• 한국안전학회지
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• 제33권2호
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• pp.21-27
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• 2018

The expansion and stable operation of electric power facilities are important factors with development of industrial facilities in modern society. In high-voltage equipment such as GIS, the insulation characteristics may be deterioated by environment-friendly gas adaption and miniaturization. There is also the possibility of accidents due to insulation breakdown due to the deterioration of power facilities. Therefore, it is necessary to extend the diagnosis system to continuously monitor the danger signals of these power equipment and to prevent accidents. Most of the internal defects in the GIS system are conductive particles, floating electrode defects, protrusion defects, and the like. In this case, a partial discharge phenomenon is accompanied. These partial discharge signals occur irregularly and various noise signals are included in the field, so it is difficult to evaluate the reliability in the development of the diagnostic system. In this paper, a study was made on equipment capable of generating a partial discharge simulated signal that can be adjusted in size and frequency to be applied to a diagnostic device by electromagnetic wave detection method. The PD simulated pulse generator consists of a user interface module, a high-voltage charging module, a pulse forming circuit, a voltage sensor and an embedded controller. In order to simulate the partial discharge phenomenon similar to the actual GIS, a discharge cell was designed and fabricated. The application of the prototype pulse generator to the commercialized PD diagnosis module confirmed that it can be used to evaluate the performance of the diagnostic device. It can be used for the development of GIS diagnosis system and performance verification for reliability evaluation.

• 한국인터넷방송통신학회논문지
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• 제22권5호
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• pp.111-116
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• 2022

전동기 소손의 원인으로는 과부하, 결상, 구속, 층간단락, 권선의 지락, 순간과전압의 유입, 회전자가 고정자에 닿는 경우 등 절연파괴로 이어져 고장 또는 전기 사고로 이어지고 있다. 따라서 기기 고장은 기기의 보수/수리에 필요한 비용에 의한 손실뿐만 아니라, 전동기가 포함된 공정 자체를 멈추기 때문에 공정 정지에 따른 생산성 저하에 의한 막대한 경제적 손실을 초래한다. 전동기의 고장을 진단하기 위한 현재의 기술의 수준은 진동, 열, 전력분석 방식을 이용하고 있지만, 고장에 따른 상당 부분의 시간이 진행되어야 문제점을 분석할 수 있는 한계점을 가지고 있다. 따라서 본 논문에서는 이러한 문제점을 해결하고자 DC AMP 신호를 이용하여 절연저항을 측정하는 장치 및 알고리즘을 산업용 전동기에 적용하여 절연저항 상태값을 추종하여 기존방식에서 해결되지 못한 전동기의 열화 및 고장 진단을 제안한다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 E
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• pp.2155-2157
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• 1999

This paper describes a new measurement method of resistive current and the technique of deterioration diagnosis for ZnO element. The consequence of current increasing (resistive current) with time is the eventual attainment of a state of thermal instability that may lead to arrester failure. So, it is very important to measure a leakage current of ZnO arrester installed at on-state. For the high-precision and more reliability, an iron core, which has a very high relative permeability, was used for increasing detection sensitivity, and we also used the personal computer for the data storage and program and analysis. And we have verified the reliability and performance of the sensing device through several laboratory tests.

• 한국구조물진단유지관리공학회 논문집
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• 제27권6호
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• pp.102-110
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• 2023

국내 고속도로 교량 중 가장 많은 비중을 차지하고 있는 PSC-I 거더교의 최근 10년간 정밀 안전진단 데이터의 상태등급을 분석한 결과 41.3%가 C등급으로 나타났다. 노후화되는 교량이 증가함에 따라 선제적 관리가 중요시되고 있다. 바닥판과 거더는 손상 및 열화 발생 시 교체 주기가 길어 교량의 서비스 및 노후도에 미치는 영향이 매우 크다. 또한 신축이음과 교량받침 등의 장치 손상 발생 비율도 높아 교량 부재에 미치는 영향에 대한 연구가 필요한 실정이다. 따라서 본 연구에서는 단경간 및 다경간 대표 PSC-I 거더 교량을 선정하여, 교량의 주요부재 및 부재 장치의 단일손상과 바닥판의 열화가 결합된 이종손상 시나리오를 정의하였다. 이종손상이 발생한 경우 단일손상이 발생한 경우보다 균열 발생 면적이 증가하였으며, 단경간 교량의 경우 교량받침 손상으로 인해 거더 균열 분포가 크게 확산되었으며, 다경간 교량의 경우 신축이음 양면손상으로 인해 바닥판의 균열분포가 크게 확산되었다. 이를 통해 교량 장치 손상이 발생하였을 때, 신속한 보수 및 교체가 이루어지지 않으면 손상 발생과 손상 확산으로 2차 피해를 유발할 수 있어, 바닥판 및 거더의 응답에 대한 지속적인 관찰과 대응이 필요할 것으로 판단된다.