径向电场诱发的高压交联聚乙烯电缆绝缘屏蔽烧蚀规律研究OA

Corrugated aluminum sheath is used widely in high-voltage cross-linked polyethylene(XLPE)insulated cable due to its excellent bending performance.However,in recent years,there have been many cable ablation fail-ures from the buffer layer,which will seriously develop to the insulation shield layer and even the insulation layer.In this paper the ablation mechanism of insulation shield due to radial electric field is studied.The ablation mechanism of insulation shield is deduced by simulating the discharge of insulation shield in different gaps.The experimental re-sults show that the buffer layer will develop inward after ablation,resulting in insulation shield ablation.The break-down,in the case of spacing,is the air breakdown between the buffer layer and the insulation shield sample as well as the electrode.While,in the case of no spacing,the breakdown is the insulation shield ablation caused by the elec-trode directly penetrating the buffer layer.The ablation of the buffer layer will greatly affect the electrical perfor-mance of the insulation shield.It is therefore necessary to focus on the ablation faults at the contact point between the aluminum sheath and the buffer layer,which is conducive to preventing cable failure and ensuring safe and stable operation of power grid.