• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 합동 추계학술대회 논문집 정보 및 제어부문
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• pp.391-394
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• 2002

In this paper, we describe the implementation of a monitoring and diagnostic system for Gas Insulator Switchgear(GIS). This system monitors operation status of GIS and transmits data from GIS to host. With this system, a operator can monitor a operating condition and judge the aging of each device, and prevent the failure or breakdown in advance.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 춘계학술대회 논문집 유기절연재료 전자세라믹 방전플라즈마 연구회
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• pp.66-68
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• 2001

Recently polymer insulators are being used for outdoor high voltage applications. Polymer insulators for transmission and distribution line have significant advantages over porcelain and glass insulators, especially for ultra-high voltage(UHV) transmission lines. Their advantages are light weight, vandalism resistance and hydrophobicity. In this paper, distribution polymer suspension insulator has been designed and investigated electric field distribution by FEM.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 하계학술대회 논문집 C
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• pp.1330-1331
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• 1995

This paper deals with the design of conductor stringing of KEPCO 765kV transmission line. The main subject in the design of conductor stringing is the determination on what the stringing tension is. According to the stringing tension, the weight and height of towers and the strength necessary for conductor, hardware, insulator vary, and the construction cost and the reliability of tower are affected largely. Therefore, in order to determine the optimum condition for stringing conductors, We appraised various items : estimation of economic comparision, strength appraisal of conductor, hardware, insulator, etc. After studying these entirely, we present the condition of condutor stringing for KEPCO 765kV transmission line.

• Nuclear Engineering and Technology
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• 제40권2호
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• pp.139-146
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• 2008

This paper presents two of the fuel channel designs being considered for the CANDU-SCWR, a pressure-tube type supercritical water cooled reactor. The first is an insulated pressure tube design. The pressure tube is thermally insulated from the hot coolant by a porous ceramic insulator. Each pressure tube is in direct contact with the moderator, which operates at an average temperature of about $80^{\circ}C$. The low temperature allows zirconium alloys to be used. A perforated metal liner protects the insulator from being damaged by the fuel bundles and erosion by the coolant. The coolant pressure is transmitted through the perforated metal liner and insulator and applied directly to the pressure tube. The second is a re-entrant design. The fuel channel consists of two concentric tubes, and a calandria tube that separates them from the moderator. The coolant enters between the annulus of the two concentric fuel channel tubes, then exits the fuel channel through the inner tube, where the fuel bundles reside. The outer tube bears the coolant pressure and its temperature will be the same as the coolant inlet temperature, ${\sim}350^{\circ}C$. Advantages and disadvantages of these designs and the material requirements are discussed.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.776-779
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• 2001

The main objective of this paper is to design and mechanical strength analysis of UHV(Ultra High Voltage) suspension insulator. One of the important properties required for suspension insulators is mechanical strength under tensile load. The cement and porcelain part are express according to change of pin head type an aspect mechanical stress. These insulators are designed and produced by using the computer analysis of mechanical, electrical and electrical stresses together with the technical know-how accumulated from long years of study into every respect of insulators.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 1993년도 추계학술발표회논문집
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• pp.97-102
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• 1993

The application of epxy composite materials for the outdoor insulating systems has some significant advan-tages compared with conventional inorganic materials, that is low weight in combination with high mechanical strength, small dimensions and design versatility. The paper describes the results of high voltage investigations carried out different aging types of epoxy resin insulator and silicone grease coating. The insulators have been exposed 3000 hours to weather-o-meter and 12 months to outdoor. In this connection, the main study of paper is form the basis of develop-ment of principal technologies of epoxy composites which ard: (1)manufacturing of insulator, (2)high vol-tage testing under dry and wet condition, (3)mechani-cal properties, (4)accelerated weather-ometer test and outdoor exposed, artificial polution.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 추계학술대회 논문집 전력기술부문
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• pp.377-379
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• 2001

Contamination flashover is responsible for insulator electrical failures. Particularly, in Korea, with its perennially dry spring, the first spring rain often cause serious line outages by forming a conductive liquid film on the insulator surface. Rainwater and fog are not normally conductive but unfortunately atmospheric dust deposited on the insulator surface contains soluble salts which may lead to bad condition of insulation by combining watery and salts. Transmission design engineers have used a contamination map drawn on the traditional paper map. But it is not convenient because it does not include the information of Geographic Information accurately. This paper explains the newly developed salt contamination map program using Geographic Information System, which provide accurate geographic information. The program is designed to use four parts of datum, salt contamination levels, 345kV & 154 kV transmission lines, power plants & substations and background map. The digital background map is composed of raster files, the others are done by vector map.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 C
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• pp.1360-1363
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• 1994

Epoxy resin insulator have good electrical properties (high electric strength, high resistivity, low dielectric loss) in addition to high mechanical strength, small dimensions and design versatility. Polymer insulator, however, are subjected to aging processes, caused by the surrounding atmosphere, which may lead to degradation of their properties. This paper describes the results of a important study on the artificial pollution test, Weather-Ometer properties and rotating wheel dip test of high voltage different aging insulators which are the most important factors for outdoor uses. Also, the objects of this paper are to (a)result of insulator under dry(wet) flashover voltage, (b)artificial pollution test of salt spay, (c)Accelerated aging test of Weather-Ometer, (d) wet and dry flashover voltage under rotating wheel dip test.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 하계학술대회 논문집
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• pp.443-446
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• 2002

In this paper, a phase difference of liveline insulator was measured and analyzed to estimate the contamination degree. The probability of accident rises according to the increase of the contamination. So the estimation of contamination degree is very important in design and maintenance of outdoor insulator. There are many methods to measure the contamination degree, but those methods use the spacial sense to measure the contamination degree. So, we have no information about the contamination from the liveline insulator, but there is a measurement of phase difference to estimate the contamination degree. The phase difference is varied with the increase of ESDD, so the contamination degree could be estimated by using those characteristics. The experiment is performed to analyze the interrelationship between contamination degree and phase difference. The variable condition is relative humidity that increases from 30 to 100 % in a chamber. We use the DAS program to measure and analyze the data. From the result, the variation of phase difference is different by the contamination degree, so we can confirm the possibility of estimating the contamination degree by the phase difference.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 C
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• pp.1639-1642
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• 1994

The severe conditions such as rated voltage of 800kV, gas pressure of $5kg/cm^2$ and rated lighting impulse withstand voltage of 2400kV were adopted for the design of spacers in the 800kV GIS to give a sufficient design margin. The design criteria on the maximum electric field strength of the center conductor and the insulator surface were established by considering the insulator surface characteristics, electrode area and surface effects in the unequal electric field strength of the given gap. The design parameters such as inter/outer envelope degree, thickness, inter/outer inserts, triple junction gap were determined by calculating the electric field using FLUX-2D program package and by referring to the published papers. The mechanical stress analysis was conducted on the feasible model spacers that showed good electric field distributions to confirm the sufficient mechanical design margin. The 800kV spacer designed as described above is now in the process of manufacturing.