• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.522-525
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• 1999

The electrical characteristics of 3 year field-aged polymer insulators which dismounted from five regions were investigated. There was a little difference in PD inception voltage depending on the manufacturers and the regions. The results between PD and SD showed a close relation. There were no significant changes in electrical properties. So, it can be considered that the field-aged insulators are sound for the present.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.7
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• pp.47-56
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• 2010

Faults due to salt damage prevent the provision of stable power supply because they affect large areas and require much time and man power for recovery. Korea, three sides of which are surrounded by sea, is especially exposed to the impact of sea winds and typhoons. Therefore, salt damage to power facilities is one of the greatest problems of Korea's power system. To prevent salt damage pollution of insulators, the salt damage deposit on the insulators is regularly measured, and the insulators are washed when their salt damage deposits are expected to reach a critical level. When salt is detected on the insulators, however, errors are likely to occur according to different workers and environments. Therefore, a leakage current measurement method was proposed in this study to check the salt damage pollution level and reduce these errors.

• Proceedings of the KIEE Conference
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• 2001.11a
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• pp.155-157
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• 2001

Various types suspension insulators made of toughness glass or porcelain are used in the power transmission. And, Insulators are continually subject to mechanical and electrical stresses which depend on the characteristics of the line. The main factor that influence the increase in reliability of insulators. In operation is the capacity of the design to withstand the certain load over a long time, the mechanical strength of the insulators. This paper describes the results of a study on the stress analysis of suspension insulator based on the finite element analysis using NASTRAN. And, the mechanical strength was evaluated through such as kinds of pin type.

• Journal of Electrical Engineering and Technology
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• v.8 no.6
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• pp.1503-1511
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• 2013

This paper deals with the analysis of leakage current characteristics of silicone rubber insulator in order to develop a new condition monitoring tool to identify the flashover of outdoor insulators. In this work, laboratory based pollution performance tests are carried out on silicone rubber insulator under ac voltage at different pollution levels and relative humidity conditions with sodium chloride (NaCl) as a contaminant. Min-Norm spectral analysis is adopted to calculate the higher order harmonics and Signal Noise Ratio (SNR). Choi-Williams Distribution (CWD) function is employed to understand the time frequency characteristics of the leakage current signal. Reported results on silicone rubber insulators show that the flashover development process of outdoor polymer insulators could be identified from the higher order harmonics and signal noise ratio values of leakage current signals.

• 제어로봇시스템학회:학술대회논문집
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• 1994.10a
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• pp.202-206
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• 1994

Mathematical model of the pollution rate of substation insulators is constructed, taking the model parameters as wind speed, wind direction, typhoon conditions and rainfall in an hourly basis. The main feature of model construction is to distinguish the effect of each parameter by separately analyzing the positive and negative pollution causing factors. Model parameters for the insulators of Karatsu substation, Saga, Japan were estimated and model validation was done using the actual data, in which the pollution deposits on the insulators were measured using pilot insulator and 'salt meter'. The proposed model of the pollution rate [mg/cm$^{2}$/hr] enables the identification of the effective parameters and prediction of the pollution rate so that it helps for the automatic decision making for insulator cleaning or the model can be used as a tool for the substation engineers to make precautionary measures.

• Journal of Information Display
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• v.9 no.2
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• pp.1-4
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• 2008

In this study, we investigate the capacitance-voltage (C-V) characteristics of metal-insulator-semiconductor (MIS) capacitors consisting of pentacene, as an organic semiconductor, and polymeric insulators such as poly(4-vinylphenol) (PVP) orpolystyrene (PS) prepared by spin-coating process, to analyze the interfacial characteristics between pentacene and polymeric insulators. Compared with the device with PS, the MIS capacitor with PVP exhibited a pronounced shift in the flat-band voltage according to the bias sweep direction. This hysteric feature in the C-V characteristics is thought to be attributed to the trapped charges at the interface between pentacene and PVP owing to the hydrophilicity of PVP. From the experimental results, we can conclude that surface polarity of polymeric insulator has a critical effect on the interfacial properties, thereby affecting the bias stability of organic thin-film transistors.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.266-267
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• 2008

The flashover of insulators in vacuum is the main factor to limit the performance of insulation in vacuum insulation system. It is believed that the pre-flashover phenomena would play a very important role in the procedure of the flashover in the interface between the insulators and vacuum. This paper is mainly concerned on the pre-flashover phenomena of Alumina insulators in vacuum. There are 24 different types of alumina insulators were tested with a 0.7/4 ${\mu}s$ pulsed voltage under a $1\times10^{-4}Pa$ vacuum. The observed pre-flashover phenomena were classified and the pre-flashover characteristics were concluded. It is useful to study further on the flashover mechanism in vacuum.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.05a
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• pp.931-936
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• 2004

In this paper, vibration endurance test is carried out on rubber insulators used fur vehicle air cleaners. Based on the test results, endurance characteristics depending on type and material of the insulators are estimated. Frequency response characteristics of the air cleaner system are investigated to identify the cause of wear and failure in the insulators occurred during the endurance test. New insulator models with improved endurance characteristics are proposed by changing the frequency response property of the air cleaner system.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.426-428
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• 2015

The NGK suspension insulators are subjected in harsh environments in service above 40 years long time. The long term reliability of the insulators is required for both mechanical and electrical performances. This study describes some electrical performances according to KEPCO-standard. There was fail in electrical and mechanical performance test such as galvanizing, low-frequence wet flashover voltage, puncture and combine mechanical & electrical strength test. The NGK suspension insulators of 1968 were shown lower electrical and mechanical performance than those of 1979.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.1181-1186
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• 2008

Insulators which are used in the domestic electrical industries are mostly depended on importation from some advance countries. Even though insulators which are made of ceramic material have been mostly used domestically, the ratio of usage on composite insulators is recently being increased because of difficulties in manufacturing and high cost regarding ceramic stuffs. In this research, we are trying to develop the composite insulators which are very efficient in insulation regardless of the matter of weight. Even though the technique of manufacturing composite insulator are quite generalized worldwide at the moment, one of the most important issue is to keep security on the know-how that an ingredient of insulated material named 'SF6 gas' is included. Therefore, The aim of this paper is to improve the bonding force and air tight property between two components of composite insulator, Flange and FRP Tube.