• The Transactions of the Korean Institute of Electrical Engineers C
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• v.49 no.3
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• pp.196-201
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• 2000

It is very important not only to detect PD signal but also to locate PD source in power cable line including its accessories. In this paper, the PID localization technique using interruption of metal sheath of cable or accessory is described. By interruption of metal sheath, the polarity of PD pulse to be measured on each part can be compared. With this technique, the exact location of PD in the accessory which has some defects can be found. Although the 'Soft' interruption method, that is, cable sheath is divided by semi-conductive layer with the resistance of higher than 1 k$\Omega$, was used instead of 'Hard' interruption method, it is also possible to detect exact location of PD. This technique is considered to be very effective for detecting PD localization in the type test of cable and accessories.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.49 no.3
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• pp.186-195
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• 2000

In this paper, partial discharge (PD) measurement was performed to evaluate the quality of the cable joint and termination constructions. The resistive coupling technique for PD detection using resistivity of semiconducting layer of the cable in the accessories, such as joints and terminations. With high frequency PD (HEPD) measurement, an excellent sensitivity below 20pC could be achieved under unshielded condition. The localization of the defects in the accessories could be identified. During heating cycle, PDs were monitored and analyzed. At that time, the PDs were dependent on the temperature of the heating cycle and showed cyclic behaviors, which were attributed to local delamination of the interfaces, between epoxy unit and stress relief cone(SRC) and between SRC and cable, due to the difference of thermal expansion. As a conclusion, HFPD measurement technique was proven to be an effective diagnostic method for qualification of extra high voltage (EHV) cable accessories. With this technique, the optimal design of the components of the accessories could be verified not only in an early stage but also under operating condition. This technique would result in the improvement of the reliability of the EHV cable accessories.

• Proceedings of the KIEE Conference
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• 2003.10a
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• pp.123-127
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• 2003

액상실리콘으로 이루어진 초고압전력케이블용 프리몰드 접속재의 반도전-절연체 계면접합체를 다양한 제조조건과 조합별로 제조하여 계면접착력에 대한 영향을 검토하였다. 후가교적용 시 계면접착력이 강화되며 grade조합에 따른 특성차이가 존재하였다. 하지만 고온 장시간의 후가교 조건에서는 계면간의 화학적 결합력의 저하로 인해 오히려 접착력이 낮아지기도 하였다. 절연 RTV와의 계면접착성은 S-1재료가, 절연 LSR의 경우에는 S-3 재료가 가장 우수하였으며 도전안정성 측면에서도 S-3 재료가 상대적으로 유리하였다. 매입형 전극체를 제조하여 절연파괴거동을 연구한 결과 계면접착성과의 직접적인 상관관계는 크지 않음을 알 수 있었다.