高压XLPE电缆金属护套与绝缘外屏蔽层放电特性研究

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。本文通 过分析高压XLPE电缆结构，研究了高压XLPE电缆金属护套与绝缘外屏蔽层放电现象的产生和发展。研究及仿 真结果表明：电缆内的电场分布受金属护套与绝缘屏蔽层之间放电间隙的绝缘状态影响，其放电过程发生在电缆 缆芯靠近波纹铝护套直至完全贴合的瞬间，且缓冲层的性能变化会加剧金属护套与绝缘屏蔽层之间放电。

Study of the Discharge Characteristics Between Metal Sheathing and Insulation Outer Screen in High Voltage XT PE Power Cables

The buffer layer is an important part for the high voltage cable, which afects 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. Through the analysis of high voltage XLPE cable structure, the emergence and development of discharge phenomenon between the high voltage XLPE cable metal sheath and insulation outer screen was studied. The research and simulation results show that the electric field distribution within cable is influenced by insulation condition of discharge gap, its dis¬charge process occurred in cable insulation core near the corrugated aluminum sheath until completely joint moment, and the perform¬ance of the buffer layer change will aggravate the discharge between metal sheath and insulation screen.