• 대한전기학회:학술대회논문집
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• 대한전기학회 1989년도 추계학술대회 논문집 학회본부
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• pp.75-78
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• 1989

Insulation of P.E insulated cable under the field of high-voltage will be breakdown ultimately due to the degradation process called 'Treeing' which is generated in the insulation, so long as any counter-measure suppressing or eliminating it could not be provided. In this paper as a counter-measure Dodecyl Alcohol is mixed with P.E and Treeing under the temperature variation has been observed. Results show that the larger weight ratio of Dodecyl Alcohol is stronger the effect of suppressing Tree ing in the range from room temperature to 40$^{\circ}C$ and generated Treeing has been soon eliminated and it never again generated.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 추계학술대회 논문집 Vol.17
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• pp.69-72
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• 2004

In order to use HTS tape on electric power applications, such as cable, motor, transformer, fault current limiter, a long length of HTS tape with a good uniformity of critical current is inevitable. The longer length of HTS tape, the wider in the range of application and the lower cost of HTS tape. In this study three long length Bi-2223/Ag tapes(268m, 253m and 187m) were fabricated. Critical current uniformity along the length was greatly improved through the optimization of cold deformation and thermo-mechanical process. Average critical current of the tapes was 63.2 A, 54.6 A and 64.2 A, respectively Critical tensile strength and critical bending radius (77 K, 5 % Ic degradation) was 135 MPa and 56 m, respectively.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 추계학술대회 논문집 학회본부
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• pp.389-391
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• 1995

Using as an alternate of insulating material for outdoor and cable, however, it has still many problems to be solved in the field of material such as resistances of environment and tracking. In this paper, Tracking property of PVC filled with aluminum hydroxide have been investigated by ASTM D 2303 method. It was found that time to track of PVC filled aluminum hydroxide was longer than that of unfilled PVC. Tensile strength and elongation of PVC were decreases increased with aluminum hydroxide contents. On the other hand, Thermegravimetry of PVC decreased. Therefore, the increase of time to tracking breakdown by antitracking additive can be explained by increased degradation temperature of polymer.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 추계학술대회 논문집 학회본부
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• pp.296-298
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• 1995

This paper proposes a new filter topology that suppresses the high voltage gradient(dv/dt) in ac motor terminals. The high voltage gradient(dv/dt) causes over voltages on the motor windings, the degradation or motor insulation, and the bearing failure. Moreover surge voltage with high voltage gradient(dv/dt) in the PWM inverter red drive system where long line cables are required causes more serious problem to the motor. Thus, the most advisable method is attaching output filter to the inverter output terminals. The conventional output filters have several problems such as bulky size, difficulty or parameter tuning. The proposed filter can be relatively smaller than the conventional filters. By the proposed filter, the shaping or PWM waveform can considerably suppress high dv/dt in motor feeding cable from the inverter. The effectiveness or the proposed filter is compared with that or the conventional one and is verified by the computer simulation.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 추계학술대회 논문집 학회본부
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• pp.406-410
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• 1995

A superconducting cable is one of the promising methods of undground transmission of high electric power in the future. It is very important that composite insulation system of $LN_2$ and polymer films takes into consideration for application high $T_c$ superconductor. This study is about both the partial discharge and properties V-t in $LN_2$. As result, applied voltage doesn't depend on the radius of non-eroded area but eroded area. And eroded area is observed the formation such as the ring of a tree.

• 전기학회논문지
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• 제61권6호
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• pp.827-832
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• 2012

The crosslinked polyethylene (XLPE) is the most widely used insulating material for power cable. Due to its thermosetting characteristics, the XLPE can not be recycled, while the needs for the environmental friendly and recyclable insulator is rapidly increasing. In this paper, some important and basic electrical properties of non-crosslinked polyethylene such as conduction current characteristics, water the tree characteristics, AC breakdown test were experimentally investigated. It was shown that some of the tested samples had better performances from the application point of view for replacing current XLPE.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2015년도 제46회 하계학술대회
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• pp.1216-1216
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• 2015

In this study, the author apply the VLF(Very Low Frequency) tan-delta data that has been measured at each office of the KEPCO 2012 to the Weibull distribution which is the statistical analysis as previous studies for the remaining life prediction through the improvement of the sensitivity and reliability of the degradation state assessment of underground distribution power cables. Also, in this paper, UCD(Used Cable Diagnosis) Matrix proposed by KEPCO was applied to the hierarchy of assessment prioritization. it suggests Aging Index for condition assessment and high reliability of proper economic replacement cycle using the weight according to the assessment prioritization.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
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• pp.262-265
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• 2001

In order to investigate the water tree degradation behavior on XLPE cable, direct voltage of 200 to 800V has been applied to the material at $50^{\circ}C\sim100^{\circ}C$. and the water tree property has been correlated with voltage and temperature in this study. The leakage current was shown to increase as temperature increased and the Ohm's law was generally satisfied in this experiment though some experimental errors were found. The leakage current was shown to decrease and reach to the stable state with time. It was also shown that the time for the stabilization of leakage current was lessened as voltage increased

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 추계학술대회 논문집 학회본부 C
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• pp.491-493
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• 2000

The performance of insulate materials gets worse with stress time in power system and because this causes lowering of function and accidents in equipment, development and performance improvement of excellent insulate materials are needed to make stable system. In this paper, to study the influence of degradation in XLPE, inner semiconducting layer and outer semiconducting layer, we studied dielectric characteristics at temperature $25{\sim}100[^{\circ}C]$ and frequency $20{\sim}1[MHz]$ and volume resistivity at temperature $25{\sim}100^{\circ}C$, voltage.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 춘계학술대회 논문집 유기절연재료 전자세라믹 방전플라즈마 연구회
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• pp.193-196
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• 2001

XLPE is occasionally happened to deteriorate cable insulation characteristics. It is happened to do a breakdown state by the degradation of electrical characteristic and electrical breakdown strength. I prepared TR-XLPE (Tree-Retardant XLPE) as adding various additives to prevent its states. Various additives are treeing retardants, anti-oxidants. Treeing retardants three kinds of aromatic compounds as adding each additive. Anti-oxidants use quinone compound and cresol compound as adding each additive. In order to observe each electrical characteristics, I measured breakdown strength, relative dielectric constant$({\varepsilon}_r)$, dielectric loss tangent$(tan{\delta})$. TR-XLPE specimens as adding treeing retardants and anti-oxidants enhance breakdown strength, ${\varepsilon}_r$, $tan{\delta}$ than pure XLPE.