• Proceedings of the KIEE Conference
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• summer
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• pp.566-568
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• 2004

최근 한국전력은 중국, 인도 둥 동남아시아 지역을 주요대상으로 자체개발한 종합배전자동화시스템을 수출하고자 활발하게 접촉하고 있다. 이들 대부분 수출대상 주요국가의 배전계통이 비접지로 운영하고 있어 배전계통 운영자의 공통된 관심사가 지락고장이 발생한 경우에 고장처리 방법이다. 비접지 계통은 단락고장의 경우 고장전류가 커 쉽게 고장구간 탐색이 용이하지만, 지락고장의 경우 고장전류가 매우 적어 배전자동화시스템에서 지원하는 고장처리 기능을 수행하기에 곤란하다. 따라서 해외시장의 기술적 우위확보와 종합배전자동화 시스템의 다목적 기능을 수행하고자 연구를 시작하였다. 지락고장이 발생하였을 때의 각종 파라메타를 중심으로 검토하였으며, 영상전압과 영상전류의 위상을 비교하여 고장구간 탐색기법을 제시하였다. 현재 연구결과를 바탕으로 현장실증시험이 진행되고 있다.

• Proceedings of the KIEE Conference
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• 2001.07c
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• pp.1667-1669
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• 2001

The clack of Insulator, which results from internal or external surges such as electrical, mechanical, and thermal stress, might cause ground fault and a power failure without proper repairs. In order to minimize losses caused by a short-term or long-term power failure, it is necessary to detect the deteriorated insulator as early as possible. To do so, we will develop a new device, which can detect and trace an deteriorated insulator by monitoring its physical change the variation of frequency spectrum. This device will do so by finding a Periodic wave sharp (120 Hz), a peculiar wave generated by defused electricity.

• 한국지구물리탐사학회:학술대회논문집
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• 2009.05a
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• pp.73-87
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• 2009

Geophysical survey for unconformity-type uranium deposit applied to this study area in Athabaska Basin, Canada were carried out airborne TEM and magnetic, resistivity-induced polarization (DC-IP), puser seismic reflection and well-logging method. The results of airborne survey interpreted the lithological boundary, geological structures, and conductors. Also, these results decided to main targets for ground DC-IP survey. The Low resistivity and the high chargeability slices of 3D modeling interpreted from DC-IP survey response for conductors related to hydrothermal alteration zones and fault-controlled graphitic zones occurring at the unconformity-type uranium deposit, and they confirmed by diamond drilling. Seismic results interpreted to lake bottom surface, alluvium layer and intra-sandstone faults. We suggest the resonable field data acquisition of DC-IP method on the land or the lake in Athabaska Basin.

• Journal of Industrial Technology
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• v.35
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• pp.41-45
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• 2015

This paper presents a development of the ELB (Electronic Leakage Breaker) based on a reduction of standby power dissipation as with maintaining conventional performance. In order to minimize the standby power consumption of the conventional circuit, we analyze the cause of 0.3W dissipation of the circuit. By employing the TR-triggered circuit to secure the standby power of 0.10W after testing and evaluation while CRD inserted circuit showed the performance of 0.17W levels. Implementing SMPS IC and TNR device circuit was designed and showed of its power to less than 0.06W. Developed ELB is expected much standby power savings in large power distributor or heavy users.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.2013-2014
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• 2008

6.6KV 고전압 위험으로 접지계기용변압기(GPT)와 영상변류기(ZCT)의 2차측에 전압 전류 시험 유입방식으로는 해당 지락보호계전기의 정.부동작이 정확한지 검증이 되지 않아 안전사고 발생의 우려성이 존재하고 있었으며, 이의 해결을 위하여 6.6KV 고압측에 인공지락시험을 통하여 국내외 일부 계전기의 동작 전압 전류 극성이 사양과 상이한 것을 발견하여 실계통에 합당하도록 시정함과 동시에 감전시 인체 저항을 감안한 지락보호계전기(OVGR, SGR) 정정값을 도출하여 인명을 보호하게 하기 위한 지락보호계전 시스템에 대한 연구이다.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.276-277
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• 2015

As the effect of global warming continues, surge rates in Korea are also getting increased. Although there are devices to protect distribution line from the surge like lightning arrester, insulation of the lightning arrester can be destroyed if frequent surge occurs in distribution line. This paper assumed that the lightning surge hits the lightning arrester and make this device's insulation destroyed. This paper also simulated these processes utilizing EMTP/ATPDraw and verified voltage behavior when faults such as line to ground fault due to frequent lightning surge occur in lightning arrester.

• Proceedings of the KIEE Conference
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• 2002.11b
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• pp.53-58
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• 2002

Sheath circulating current is increased as the change of sheath mutual impedance which is caused by imbalance of cable system, and different section length between joint box. If excessive current flows in sheath. sheath loss will be increased and then transmission capacity of underground transmission system is reduced. Accordingly, This paper proposed sheath current reduction device using resistor and reactor and proved the reduction effect of that device using EMTP/ATP. And also in this paper, when transients are occurred at the underground system with reduction device by ground fault and lightning surge. we analyzes transient effect of system variously. From this result. authors establish the protection methods of sheath circulating current reduction device.

• Proceedings of the KIEE Conference
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• 2002.07c
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• pp.1721-1723
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• 2002

This paper deals with the analysis of field condition for earth leakage current alarming system in the stage lighting, stage sound stage machinery installation. These analyses of field condition were carried out in accordance with investigating an installation of earth leakage current alarming system with respect to a main line of power source, dimmer, sound equipment, machinery mobile unit equipment and so on. As a result of analyses. The earth leakage current alarming system has been installed only a part of the main line of power source and the probability of places which were installed was less than 50(%). Therefore, it is desirable that the earth leakage current alarming system is installed at places which are suitable, for example, dimmer, each kind machinery etc. in order to prevent electrical hazard.

• Economic and Environmental Geology
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• v.20 no.4
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• pp.213-221
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• 1987

The Donghae mine locates at Jangjoari, Koseongun, Kyongsang-nam-do. The geology of the mine consists of the upper part of Chin dong Formation conformably overlain by tuffaceous Koseong Formation. These formations are intruded by the granodiorite and the basic dikes. The ore mineralization occurs in the fault breccia pipe at the center of a granodiorite stock. The estimated dimension of the breccia pipe is $7m{\times}70m{\times}200m$. The host rock has distinctive hydrothermal alteration halos consisting hematite zone, chlorite zone, epidote zone and sericite zone from outer zone to the ore vein. The ore mineralization occurred in the three distinctive stages. The ore minerals formed in the first stage are pyrite, sphalerite, chalcopyrite, stannite and tetrahedrite. Galena and arsenopyrite are formed in the second stage. Some sphalerite grains include exsolution dots of the chalcopyrite. It is suggested that the ore mineralization occurred by a boiling of a hydrothermal fluid during its initial stage and subsequent cooling and $CO_2$ fugacity drop of remaining hydrothermal fluid by a ground water mixing aided vertical zoning of the ore minerals.

• Journal of Energy Engineering
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• v.9 no.3
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• pp.243-249
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• 2000

대체에너지에 대한 연구가 활발히 진행됨에 따라 향후 배전계통은 신 에너지 전원 등과 같은 분산형 전원과 연계되어 네트워크 형식으로 구성될 것으로 예상된다. 이러한 배전계통의 변화는 지락 및 단락 사고 시 기존의 보호협조에 있어서 많은 문제점을 발생시킬 것이며, 이러한 배전계통의 변화와 전력 고품질 요구에 대응하기 위해서는 새로운 보호협조 체계가 필요하다. 새로운 보호협조 방식의 개발을 위해 필수적인 지락과 단락사고 시 배전계통의 사고 데이터는 실제 운영 도중에 얻기 어렵다. 본 논문에서는 기존 전원시스템 및 신 에너지 전원을 포함한 새로운 배전계통의 운용시 발생할 수 있는 사고 상황을 예측하고 고장 데이터를 수집하기 위해 저압 배전선로에 인위적으로 지락 및 단락을 발생시킬 수 있는 장치의 개발에 대해 서술한다. 개발한 시험장치의 기능을 확인하기 위하여 실제 배전계통에 적용하여 지락 및 단락 시험을 수행하여 전압 및 전류 파형을 측정·분석하여 시험장치의 신뢰성과, 효용성을 검증하였다.