【摘要】 220 kV线路会存在OF电缆与XLPE电缆并存的现象,必须合理分析混合电缆传输系统的雷电侵入波暂态特性,以提高其防雷水平。本文利用ATP-EMTP建立220 kV OF电缆与XLPE电缆混合传输线路模型,分析绕击和反击情况下的暂态特性,比较OF+OF+OF、OF+XLPE+OF、OF+OF+XLPE安装方式下电缆线芯暂态过电压,讨论电缆长度对暂态过电压的影响,最后分析安装护套层过电压保护器对护套绝缘的防护效果。仿真结果表明:OF+XLPE+OF安装方式下,电缆末端过电压幅值最高,OF+OF+XLPE安装方式次之,3种方式下过电压均不会对电缆内绝缘造成危害;绕击和反击侵入波过电压幅值均随着电缆长度的增加而降低;安装护层过电压保护器能够实现有效护套层绝缘保护。更多还原

【Abstract】 Combined connection of OF(oil filled) and XLPE cable in 220 kV transmission line is really existed, so it is necessary to analyze lightning invaded wave transient characteristic of combined connection operation of OF and XLPE cable to improve the level of lightning protection. Equivalent models of 220 kV transmission line with combined connection of OF and XLPE cable are established by using ATP-EMTP. The transient characteristic in case of counteracting and shielding are analyzed. The transient overvoltage of cable core under OF + OF + OF, OF + XLPE + OF, OF + OF + XLPE installation are compared, and the effect of cable length on transient overvoltage is discussed. Finally, protection effect of overvoltage protector of the coat layer on coat insulation is discussed. The results show that: the highest terminal overvoltage is in OF+XLPE+OF installation method, then in OF+OF+XLPE and OF+OF+OF installation method, but all three methods would not cause damage to inner insulation of cables.The magnitude of overvoltage around the shielding and counterattacking waves both decrease as the length of the cable increases. Overvoltage protector will protect the coat layer insulation effectively.更多还原