• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 춘계학술대회 논문집 방전 플라즈마 유기절연재료 초전도 자성체연구회
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• pp.146-149
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• 2004

In order to analyze the physical and chemical characteristics of the home production porcelain insulators by change of the alumina addition amount, 36000lbs ball socket type suspension insulators which were manufactured in 1989, 1995 and 2001 removed in transmission line and an experiment was performed. By the result, 8 wt.% alumina that influences the mechanical properties and arc resistance properties in case of insulators that were manufactured in 1989 was contained. Amount of alumina was contained most by 17 wt.% in case of insulators that were manufactured in 2001.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 추계학술대회 논문집 전기물성,응용부문
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• pp.142-144
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• 2003

The suspension insulators are subjected to harsh environment in service for a long time. Long term reliability of the insulators is required for both mechanical and electrical performances. We studied HRB characteristics to find out a deformation of suspension porcelain with alumina contents. These experimental results show that HRB intensity was affected severely by alumina contents, and the propagation properties was affected mainly by a distribution and shape of micro pores on porcelain samples.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 추계학술대회 논문집 학회본부
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• pp.411-413
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• 1995

Porcelain insulators have been used for the almost all of the suspension insulators in distribution line. However, Puncture breakdowns in porcelain insulators caused by westing cement between metal fitting and porcelain material. There is little puncture breakdown in Epoxy casting insulator. This paper presents a new design technique for the development of suspension insulator used Cycloaliphatic Epoxy resin. The design was performed on the basis of two conditions (weather conditions for the past 30 years and the existing installation conditions of KEPCO) and was proven of its adaptability by FEM method.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 E
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• pp.1807-1809
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• 1997

The salt contamination on the surface of the porcelain insulators used electric power systems causes flash-over accidents. Therefore the quantity of salt contamination should be monitored not to exceed a limit. In this study, we tried laser aided measurement of salt contamination. The Nd:YAG laser beam was focused on the surface of the porcelain insulators which were artificially contaminated, and we detected the D-Line (${\cong}589nm$) of spontaneous emission from the excited sodium atoms with a PMT and an oscilloscope. And we deduced the relation between the detected signals and degree of salt contamination.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 춘계학술대회 논문집
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• pp.157-160
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• 1999

The paper provides the results of failure analysis for the porcelain suspension insulators. The comparisons of characteristics were made as a function of failed and unfailed isulators which had been used in real distribution line. This paper also described the failure modes which could be occurred in the fields. The cracks inside cap were detected though measuring the resistance or the leakage current. The ratio of open porosity was calculated from the Archimedes Method. The failure analyses of porcelain suspension insulators were conducted from the various analysis method.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2007년도 하계종합학술대회 논문집
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• pp.291-292
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• 2007

Porcelain insulators are widely used in overhead high-voltage power transmission lines while providing adequate insulation to withstand switching and lightning over voltages. For the safety consideration, we proposed a novel insulator inspection method using harmonic, which is retrieved from the low frequency signal. The working principle of this new method is based on the relationship between the low frequency harmonic and the defective characteristic of the insulators. So, in this paper, the harmonic retrieval in the complex noise is solved with the HOC (High Order Cumulants) is extended. In the experiment, as one of our dedicated contribution, we illustrate low frequency harmonic and the defective characteristics of the porcelain insulators.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 추계학술대회 논문집 Vol.15
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• pp.476-479
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• 2002

The ageing cause in many porcelain suspension insulators which occur on transmission and distribution line with dead-end stings is mechanical stress in interface between porcelain and cement materials. It is known that the principal mechanical stress which give electrical failure is the results of the displacement is due to cement growth. We studied the effect of cement displacement resulting environmental ageing parameters on porcelain insulator mechanical properties for transmission line by simulation (ANSYS/NASTRAN program) and test methods. These simulation analysis and experimental results show that cement volume growth affects severely to be mechanical failure ageing.

• Transactions on Electrical and Electronic Materials
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• 제18권3호
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• pp.151-154
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• 2017

In this article, we investigated the various influencing factors that degraded the lifetime of suspension insulators in 154 kV transmission lines, and showed the possible solutions to avoid such breakdowns. With respect to achieve safety, reliability and aesthetical considerations, the characteristics of transmission and distribution network power cables should be improved. Suspension insulators are particularly important to study, as they have developed to be the main component of transmission lines due to their ability to withstand the electrical conductivity of high-voltage power transmission. Suspension insulators are mostly made from glass, rubber and ceramic material due to their high resistivity. In Korea, porcelain suspension insulators are typically used in the transmission line system, as they are cheaper and more flexible compared to other types of insulators. This is effective from preventing very high and steep lightening impulse voltages from causing the breakdown of suspension insulators used in power lines. Other influential factors affect the lifetime of suspension insulators that we studied include temperature, water moisture, contamination, mechanical vibration and electrical stress.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 C
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• pp.1637-1639
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• 2004

In order to analyze the physical and chemical characteristics of the home production porcelain insulators by change of the alumina addition amount, 36000lbs ball socket type suspension insulators which were manufactured in 1989, 1995 and 2001 removed in transmission line and an experiment was performed. By the result, 8 [wt.%] alumina that influences the mechanical properties and arc resistance properties in case of insulators that were manufactured in 1989 was contained, and the relative density and the fracture toughness of insulators appeared by 94.2% and 1.4 [MPa $M^{1/2}$], respectively. However, 12 [wt.%] alumina was contained in case of insulators that were manufactured in 1995, and the relative density and the fracture toughness of insulators appeared preferably lower by 92% and 1.3 [MPa $M^{1/2}$], respectively. Amount of alumina was contained most by 17 [wt.%] in case of insulators that were manufactured in 2001. It was confirmed that the electrical and mechanical characteristics such as the relative density and the fracture toughness appeared excellently by 96% and 1.7 [MPa $m^{1/2}$], respectively.

• 한국전기전자재료학회논문지
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• 제20권9호
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• pp.787-792
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• 2007

To understand the effects of forest fires on polymer insulators for transmission lines, the forest fire simulation tests were performed with polymer and porcelain insulators at Gochang testing center. These tests consisted of energizing 90 kV at line-to-ground voltage of 154 kV lines and open flame rising up to $600-630^{\circ}C$ as being measured at insulator surface. Mechanical and electrical characteristics such as specific mechanical load, leakage current, low frequency dry flashover voltage and impulse flashover voltage were analyzed for the polymer insulators before, during and after simulation tests compared with porcelain insulators. At the end of fire simulation tests, there was no detrimental deterioration of any insulators. All insulators passed the criteria of KEPCO specification. This study showed that forest fire simulation had no impact on polymer insulators.