• 조명전기설비학회논문지
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• 제22권2호
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• pp.85-93
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• 2008

현재 국내에서 사용되고 있는 22.9[kV]-y 배전 방식은 지중 케이블로 전력을 공급하고 있으며, 선로 운영상 배전 케이블 선로의 동심중성선을 케이블 접속 구간마다 3선 일괄 접지하는 3상 일괄 다중접지방식을 채택하고 있다. 이 방식에서는 동심중성선에 부하 전류의 약 40[%](전력구)${\sim}50$[%](관로)의 동심중성선 순환 전류가 발생하고 있다. 본 논문은 이와 같은 문제점을 해결하기 위하여 새로운 3상 비일괄 동심중성선 다중접지방식을 제안하고 있으며, 케이블의 허용전류계산, 케이블 차폐층의 유기전압 및 선로에서 발생하는 유도장애등의 기술적인 문제들을 종합적으로 해석하고 있다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 추계학술대회 논문집 전기설비전문위원
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• pp.218-221
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• 2008

Due to a variable noises in the field underground lines, clear technology of noises is very important in the diagnosis technology of partial discharge. Therefore we progressed filter test to improve the measuring test of partial discharge in a field. We applied to field test after making W-LC filter for partial discharge measurement, and then designed experimental environment such as under- ground distribution lines of field. Measuring sensor for test was UHF sensor. And we analysed those using the Lemke Probe and oscilloscope (TDS-3054, Tektro- nix). Finally, we obtained excellent data of noise decrement in the joint box of 22.9[kV] distribution lines from above experiment.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 춘계학술대회 논문집 전기설비전문위원
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• pp.72-74
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• 2007

Due to a variable noises in the field underground lines, clear technology of noises is very important in the diagnosis technology of partial discharge. Therefore we progressed filter test to improve the measuring test of partial discharge in a field. We applied to field test after making W-LC filter for partial discharge measurement, and then designed experimental environment such as underground distribution lines of field. Measuring sensor for test was UHF sensor. And we analysed those using the Lemke Probe and oscilloscope (TDS-3054, Tektronix). Finally, we obtained excellent data of noise decrement in the joint box of 22.9[kV] distribution lines from above experiment.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 C
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• pp.2277-2279
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• 2005

Due to a variable noises in the field underground lines, clear technology of noises is very important in the diagnosis technology of partial discharge. Therefore we progressed filter test to improve the measuring test of partial discharge in a field. We applied to field test after making W-LC filter for partial discharge measurement, and then designed experimental environment such as under-ground distribution lines of field. Measuring sensor for test was UHF sensor. And we analysed those using the Lemke Probe and oscilloscope (TDS-3054, Tektronix). Finally, we obtained excellent data of noise decrement in the joint box of 22.9[kV] distribution lines from above experiment.

• Journal of Electrical Engineering and Technology
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• 제9권5호
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• pp.1694-1703
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• 2014

Lightning induced voltage is a major factor that causes interruptions on distribution lines. In this paper, analytical expressions are proposed to evaluate a lightning induced voltage on power lines directly in the time domain without the need to apply any extra conversions. The proposed expressions can consider the widely used current functions and models in contrast to the earlier analytical expressions which had a number of limitations related to the simplification of the channel base current and the current along the lightning channel. The results show that the simulated values based on the proposed method are in good agreement with the previous studies and the proposed expressions can be used for optimizing the insulation and protection level of existing and new lines being designed.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1987년도 전기.전자공학 학술대회 논문집(I)
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• pp.685-687
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• 1987

• KEPCO Journal on Electric Power and Energy
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• 제7권1호
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• pp.171-177
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• 2021

In terms of distribution planning, accurate electric load prediction is one of the most important factors. The future load prediction has manually been performed by calculating the maximum electric load considering loads transfer/switching and multiplying it with the load increase rate. In here, the risk of human error is inherent and thus an automated maximum electric load forecasting system is required. Although there are many existing methods and techniques to predict future electric loads, such as regression analysis, many of them have limitations in reflecting the nonlinear characteristics of the electric load and the complexity due to Photovoltaics (PVs), Electric Vehicles (EVs), and etc. This study, therefore, proposes a method of predicting future electric loads on distribution lines by using Machine Learning (ML) method that can reflect the characteristics of these nonlinearities. In addition, predictive models were developed based on actual data collected at KEPCO's existing distribution lines and the adequacy of developed models was verified as well. Also, as the distribution planning has a direct bearing on the investment, and amount of investment has a direct bearing on the maximum electric load, various baseline such as maximum, lowest, median value that can assesses the adequacy and accuracy of proposed ML based electric load prediction methods were suggested.

• Journal of Plant Biology
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• 제39권3호
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• pp.203-207
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• 1996

On the basis of karyotypic analysis performed by conventional staining and Giemas C-banding technique, cytological relationship was inferred for 21 lines of Paeonia lactiflora Pal. cultivated in Korea. It was very difficult to infer their organized karyotypic classification system using the composition of somatic chromosomes involving sat-chromosomes, relative length of chromosomes, arm ratio and karyotypic formulae by conventional staining. From the distribution and number of Giemsa C-bands on the chromosomes b and c, 21 lines can be subclassified into 5 groups. It seems that the karyotypic polymorphism is observed in 21 lines of cultivated P. lactiflora because peony mainly propagates by outbreeding.

• 조명전기설비학회논문지
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• 제22권2호
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• pp.51-56
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• 2008

철도에서의 고압배전선로는 역사조명 및 동력설비, 그리고 열차의 안전운행을 위한 신호설비의 전력을 공급해주는 설비로 열차의 안전운행 및 철도 이용자의 서비스 향상을 위한 중요한 역할을 담당하고 있다. 또한 각종 전력기기의 전자화, 자동화로 인해 양질의 전력공급이 요구되며, 철도 이용자에 대한 보다 향상된 서비스를 제공과 역사내 전기에너지 사용의 급증으로 인한 전력공급의 신뢰성 확보가 요구된다. 본 논문에서는 철도고압배전계통의 고장현상을 분석하기 위하여 철도고압배전 설비 중 접지계통과 비접지계통에 대해서 사고시 전압강하가 발생 여부와 사고를 제거하기 위해 차단기를 동작시켰을 때의 서지전압에 의한 과도특성을 PSCAD/EMTDC를 이용하여 모의하였으며, 이 사고모의 결과를 토대로 비접지 고압배전계통의 보호방법에 대한 대안을 제시하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 Techno-Fair 및 추계학술대회 논문집 전기물성,응용부문
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• pp.137-138
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• 2008

In this paper, the statistical judgement using IR camera was discussed and investigated. Acceleration experiments were carried out for the possibility of weibull distribution and then, the acquired data were replaced with quantitative value for safety diagnosis of distribution lines.