• 조명전기설비학회논문지
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• 제19권2호
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• pp.138-144
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• 2005

본 논문에서는 산불이 송전용 폴리머애자에 미치는 영향을 연구하기 위해 인공화염 시험장치를 제작하여 화염의 가열 시간에 따른 폴리머애자의 갓(shed) 변화와 자기애자의 disc 변화를 관찰하고, 전기적$\cdot$기계적 실험을 통하여 특성변화를 확인하였다. 실험결과 다음과 같은 결론을 얻을 수 있었다. 첫째, 화염의 가열시간이 5분정도 경과하였을 때, 자기애자의 전기적 특성은 $80(\%)$ 정도 저하된 반면에 폴리머애자의 경우 갓 유실이 있었지만 전기적 특성의 변화는 $10(\%)$ 정도였다. 폴리머애자를 20분 가열하였을 때는 대부분의 갓이 유실되었지만 전기적 특성치는 $20(\%)$ 정도 감소하였다. 둘째, 폴리머애자와 자기애자 모두 전기적 특성치의 감소는 있었지만 기계적 특성치는 양호하게 나타났다.

• 조명전기설비학회논문지
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• 제22권4호
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• pp.147-152
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• 2008

본 논문은 코로나 방전에 의한 자기애자와 폴리머애자의 자외선 발생 특성에 관한 것이다. 자외선 카메라를 이용하여 측정하고, KS C IEC 60060-1(2006)의 전압조건을 준수하여 실험하였다. 결과로서 자기애자에서의 코로나 방전은 애자 접합면에서 가장 취약한 부분에서 시작되었다. 폴리머애자는 취약한 접합면에서 자외선이 발생하였으며, 전원 측에서 나타났다. 이로써 자외선 검출을 통해 절연애자의 취약부분이 쉽게 확인되는 것을 알 수 있었다. 또한, 기존의 초음파 검출기술과 비교하여 열화단계가 정량화될 수 있음을 확인하였다. 이는 신뢰성 있는 데이터를 통해 전력설비의 열화를 판단하는 기준에 활용될 수 있다. 향후 현장진단에 적합한 기술로서 앞으로 많은 연구가 기대된다.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제49권7호
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• pp.406-411
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• 2000

This paper presents the results of performance confirmation tests for domestic 20 [Ton] transmission suspension insulators which will be widely utilized in transmission lines. The new test methods such as power arc test, steep-front-of-wave flashover voltage test, and etc. which have been only utilized for the distribution insulators were applied in transmission suspension insulators. The properties of metal and cement used in the 20 [Ton] transmission insulators were also evaluated by the various analysis techniques. Based on the results, we evaluated the performance of the transmission suspension insulators.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 춘계학술대회 논문집 방전 플라즈마 유기절연재료 초전도 자성체연구회
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• pp.65-68
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• 2004

This paper researched leakage current characteristics of artificially contaminated EHV insulators through construction of long-term testing facility. Insulators were contaminated and classified into the ESDD contaminated levels under IEC standards method. As the test results of contaminated insulators was carried out several experiments, leakage current greatly increased during initial rainfall. After contaminated insulators were naturally washed by rain, leakage current was not increased.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1992년도 하계학술대회 논문집 B
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• pp.886-890
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• 1992

Recent investigations have been made on polymer Insulators of various types. The findings are related to experience on operational lines in foreign countries, design concepts, materials and tests about outdoor properties. Over last decade improvements have been occured in the design and construction techniques of polymer insulators. For transmission and distribution lines, it may be advantageous or even necessary to replace, the conventional porcelain or tempered glass insulators by lighter polymer insulators which have better mechanical properties.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2004년도 춘계학술대회 논문집
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• pp.392-396
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• 2004

Experimental equipments for long-term outdoor tests of EHV insulators in outdoor were constructed. The testing insulators have been energized with 89 [kV] phase-to-ground AC voltage under identical condition at station, and the investigation was carried out for leakage current and various environments such as temperature, relative humidity and wind velocity. The test results of leakage current wave trends have forms on distorted waves including harmonics. The porcelain and glass insulators have low leakage current in case of daytime because moisture and humidity have relative low values. In comparison with these conditions, high leakage current was shown at dawn and rainy day due to high humidity. However, leakage current of polymer insulators was shown approximately $129[{\mu}m]$ without relation to the weather due to hydrophobicity on their surface.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.465-466
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• 2011

The global trend is to make transmission lines light weight and compact by using insulators and other equipment made of advanced materials. In Korea, the diversification of insulators supply route has begun in order to obtain price competitiveness. In May 1999, polymer insulators were finally introduced for the first time and installed to the 154kV transmission lines. After that, the construction and procurement standards were made and domestic polymer insulators were developed. And then, foreign and domestic manufacturers were registered in KEPCO as qualified insulator suppliers. As of 2010, purchasing polymer insulators by competitive bidding from foreign and domestic manufacturers has been possible. For this reason, it was decided to reduce the use of porcelain insulators and increase the use of polymer insulators taking the installation price into consideration

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 춘계학술대회 논문집 유기절연재료 전자세라믹 방전플라즈마 연구회
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• pp.140-142
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• 2001

In this study mechanical for stress according to Pin type of high voltage suspension type insulator. R-shaped metal pin. and a tapered metal pin having a tensile pin having a tensile strength of more than the breaking strength of insulating body are provided in porcelain insulating bodies, and a suspension insulator according to the present invention, a test for determining the tensile strength of the insulating body was made and the results. These insulators are designed and produced by using the computer analysis of mechanical and electrical stresses together with the technical know-how accumulated from long year of study into every respect of insulators.

• 한국전기전자재료학회논문지
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• 제30권9호
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• pp.551-557
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• 2017

It is extremely important to improve methodologies for the lifetime assessment of porcelain insulators. While there has been a considerable amount of work regarding the phenomena of lifetime distributions, most of the studies assume that aging distributions follow the Weibull distribution. However, the true underlying distribution is unknown, giving rise to unrealistic inferences, such as parameter estimations. In this article, we review several distributions that are commonly used in reliability and survival analysis, such as the exponential, Weibull, log-normal, and gamma distributions. Some properties, including the characteristics of failure rates of these distributions, are presented. We use a Bayesian approach for model selection and parameter estimation procedures. A well-known measure, called the Bayes factor, is used to find the most plausible model among several contending models. The posterior mean can be used as a parameter estimate for unknown parameters, once a model with the highest posterior probability is selected. Extensive simulation studies are performed to demonstrate our methodologies.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제48권9호
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• pp.641-647
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• 1999

The paper provides the results of microstructure analysis and dielectricproperties of porcelain suspension insulators. The evaluation of characteristics was also made as a function of the manufacturers and fabricated years for the experimental specimens which had been used in real distribution lines. Even though the series A contained higher alumina contents than the series B, the densification of series A was lower than that of series B, resulting from much porosity. The microstructure investigation confirmed that series A had much porosity than series B. The series A contained quartz $(SiO_2),\; mullite\; (Al_6Si_2O_{13}),\; corundum(Al_2O_3),\; and cristobalite\; (SiO_2)$ phases. However, the series B had no cristobalite phase which had very high thermal expansion coefficient. Also, the tan$\delta$of series A was more abruptly increased than that of series B as increasing temperature. The elevated temperature may make much expansion of cristobalite crystal than other crystals, resulting in crack and puncture inside cap during the summer days.