Impurities of the Semiconductive Shield in the Power Distribution Cable

배전용 전력케이블의 반도전층에 함유되어 있는 불순물 분석

In order to evaluate the soundness of 10 year service-aged XLPE-insulated 22.9 kV underground distribution cables, semiconductive shields have been characterized. The edge of insulation near the insulation shield shows a drastic decrease of OIT. Impurities such as Ca, Mg, Fe, Cu were detected in both conductor and insulation shields. Their concentrations at the insulation shield are much higher than those at the strand shield. All these facts suggest that the edge of insulation near the insulation shield is degraded considerably, which might be attributed to the oxidation reaction of insulation by a large amount of impurities in the insulation shield.