• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.2
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• pp.1135-1138
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• 2003

The transformer is major equipment in power receiving and substation facilities. Necessary conditions required for the transformer are compactness, lightness, high reliability, economic advantages, and easy maintenance. The pole-mount transformer installed in distribution system is acting direct role in supply of electric power and it is electric power device should drive for long term. Most of modem transformer are oil-filled transformer and accident is happening considerable. The mold transformers have been widely used in underground substations in large building and have some advantages in comparison to oil-transformer, that is low fire risk, excellent environmental compatibility, compact size and high reliability. In addition, the application of mold transformer for outdoor is possible due to development of epoxy resin. The mold transformer generally has cooling duct between low voltage coil and high voltage coil. A mold transformer made by one body molding method has been developed for small size and low loss. One body molding transformer needs some cooling method because heat radiation between each winding is difficult. In this paper, The thermal analysis of pole mount mold transformer with one body molding by duct condition is investigated and the test result of temperature rise is compared with simulation data.

• 한국안전학회지
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• 제26권6호
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• pp.7-12
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• 2011

In recent years, environmental concerns have been raised on the use of poorly biodegradable fluids in electrical apparatus in regions where spills from leaks and equipment failure could contaminate the surroundings. The newly invented vegetable insulating oil is highly biodegradable and have negligible impact on the environment, human health and the ecosystem. For development of the environmental-friendly pole transformer using vegetable insulating oil, the dielectric constructions of the pole transformer were discussed in this paper. Depending on the dielectric constructions, the AC breakdown characteristics of the Nomex insulating papers and the vegetable insulating oil were studied by simulated electrode systems. Based on the experimental results, the maximum design stress($E_{max}$) for insulation design of the environmental-friendly pole transformer were suggested.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.1
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• pp.212-215
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• 2003

In this paper, a model pole transformer was designed to improve the reliability of pole transformers and its short circuit withstand strength was tested. The failure causes of the pole transformers which had been operated in the field were analyzed and several patterns of the causes were determined. A novel countermeasure was devised to prevent the failures of the pole transformers in advance. A model pole transformer was designed and made in accordance with the given specifications to strengthen the short circuit withstand capability and its characteristic was tested. As a result, the advanced performance of the model pole transformer was confirmed and novel techniques in manufacturing process was suggested. It is considered that all the methods employed in the developing process will be helpful to design and manufacture the pole transformers thus the reliability of pole transformers in distribution lines will be improved.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
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• pp.810-812
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• 2005

In this paper, the short-term load forecasting of pole-transformer is performed by artificial neural networks. Input parameters of the Nosed algorithm are peak loads of pole-transformer of previous days and their temperatures. The proposed algorithm is tested for ore of the pole-transformers in seoul, korea. Test results show that the proposed algorithm improves the accuracy of the load forecasting of pole-transformer compared with the conventional algorithm.

• 조명전기설비학회논문지
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• 제17권1호
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• pp.37-44
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• 2003

본 논문에서 제안한 주상변압기 열화진단 장치는 활선 상태에서 변압기 외함온도, 2차전류 및 누설전류 등을 측정하고, 지정값 이상의 상태가 발생하면 변압기 관리자에게 유선 및 이동통신기를 통하여 자동통보함으로써 사고를 사전에 예방할 수 있다. 또한 무선데이터통신을 이용하여 수집된 정보를 분석하고 각 상별 전류분포, 이용률 및 온도변화 추이를 그래프로 나타냄으로서 각 상별 부하의 불평형 정도와 변압기의 열화 추이 상태를 파악할 수 있다. 실계통 실험을 통하여 제안한 주상 변압기 열화 진단 장치의 효용성을 입증하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 춘계학술대회 논문집
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• pp.145-149
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• 2005

Recently, polymer insulator and bushing that are used for high voltage application have some advantages such as light weight, small size, vandalism resistance, hydrophobicity and easy making process. The pole mount transformer installed in distribution system is acting direct role in supply of electric power and the electric power device should drive safely for long tenn. In this paper, the polymer bushing of pole transformer is designed adaptively to current assembly method, designed bushing is manufactured on basis of that result. The electric field of designed transformer is investigated by FEM program.

• 조명전기설비학회논문지
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• 제14권3호
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• pp.97-106
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• 2000

본 논문에서눈 주상 변압기의 유전정접 측정과 FFT의 이용으로 활선 상태에서 진단할 수 있논 열화 진단 창치를 제안하였다. 본 논문에서 제안한 주상 변압기 열화 진단 장치는 활선 상태에서 절연유위 온도와 유전정점을 측정하며, 진단 결를블 FFT로 처리한다. 진단용 센서에 인가하는 시험 전압은 주상 변압기 2차촉 전압의 0]용으로 외부회 추가 장치 없이도 전단이 가능하다. 또한, 무선 데이터 통선을 이용하여 진단 정보를 지상에서 수신함 으로 주상 변압기의 감사를 별도의 추가 설비 없이 손쉽게 가능하도록 하였다. 시험 전압 가변 실험과 온도 가변 실험을 통하여 제안한 주상 변압기 열화 진단 장치의 유용성을 입증하였다.

• 전기학회논문지
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• 제57권9호
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• pp.1507-1515
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• 2008

It is essential for electric power companies to have a quick restoration system of the faulted pole transformers which occupy most of transformers to supply stable electricity. However, it takes too much time to restore it when a transformer is out of order suddenly because we now count on operator in investigating causes of failure and making decision of recovery methods. This paper presents the concept of 'Fault pattern analysis and Restoration prediction model using Data mining techniques’, which is based on accumulated fault record of pole transformers in the past. For this, it also suggests external and internal causes of fault which influence the fault pattern of pole transformers. It is expected that we can reduce not only defects in manufacturing procedure by upgrading quality but also the time of predicting fault patterns and recovering when faults occur by using the result.

• 한국전기전자재료학회논문지
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• 제17권3호
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• pp.348-352
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• 2004

The mold transformers have been widely used in underground substations in large building and have some advantages in comparison to oil-transformer, that is low fire risk, excellent environmental compatibility, compact size and high reliability. In addition, the application of mold transformer for outdoor is possible due to development of epoxy resin. The mold transformer generally has cooling duct between low voltage coil and high voltage coil. A mold transformer made by one body molding method has been developed for small size and ow loss, but it needs some cooling method because heat radiation between each winding is difficult. The life of transformer is significantly dependent on the thermal behavior in windings. Many transformer designers have calculated temperature distribution and hot spot point by finite element method(FEM) to analyze winding temperature rise. In this paper, The thermal analysis of pole mount mold transformer with one body molding by duct condition is investigated and the test result of temperature rise is compared with simulation data.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 추계학술대회 논문집 Vol.15
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• pp.484-487
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• 2002

The mold transformers have been widely used in underground substations in large building and have some advantages in comparison to oil-transformer, that is low fire risk, excellent environmental compatibility, compact size and high reliability. In addition, the application of mold transformer for outdoor is possible due to development of epoxy resin. The mold transformer generally has cooling duct between low voltage coil and high voltage coil. A mold transformer made by one body molding method has been developed for small size and low loss. In this paper, the proto type mold transformer of 50kVA class is investigated by routine, type, special test. The outdoor energized aging test is investigated by back-to-back method to verify the long time performance of pole mold transformer. The aging process of transformer is analyzed by various diagnosis method such as DC voltage-current test, $tan{\delta}$, Meggar measurement, winding temperature and etc.