不同截面的110kV XLPE电力电缆缓冲层放电特性

高压XLPE电缆的缓冲层是电缆的重要组成部分，对电缆的机械、热、电性能具有重要的影响。而电缆在实际运行时，由于电缆的热机械运动会使得电缆金属护套脱离电缆绝缘外屏蔽，使电场分布发生改变。本文根据110kV XLPE电缆结构及实际尺寸，计算了110kV XLPE发生放电现象时对电缆金属护套与绝缘外屏蔽脱离距离的要求。计算结果表明：电缆内放电距离受金属护套与绝缘屏蔽层之间放电间隙的绝缘状态影响，同时放电间隙的减小会加剧金属护套与绝缘屏蔽层之间放电，且电缆截面越大越容易发生放电现象。

Study of the Discharge Characteristics of Buffer layer discharge characteristics in XLPE Power Cables of Different Cross Section

The buffer layer is an important part for the high voltage cable, which affects greatly the mechanical, thermal and electrical properties of the cable. If the insulation outer screen and metal sheath is not closely, the air gap between the screen and sheath will change the distribution of the electric field. In this paper, based on the 110 kV cable structure and the actual size, calculation of the requirement of discharge on the cable metal sheath and insulation outer shielding from the distance. The results show that the discharge distance within the cable metal sheath and insulation shielding layer between the insulation of the discharge gap state, and the decrease of the discharge gap will intensify discharge between metal sheath and insulation shielding layer, the easier and more cable cross section of the discharge.