一起地线融冰不成功事件原因分析及处理

Analysis and Treatment of an Unsuccessful Event of Ice Melting by Ground Wire

分析一起超高压输电线路地线融冰不成功事件的原因,确保了地线融冰成功率。通过对融冰接线电缆击穿特征分析及内部解剖检查,认为接线电缆由于受潮、机械损伤、电气距离不足、老化等原因出现击穿,致使地线融冰未能成功。利用复合支柱绝缘子作为支撑,将地线至融冰接线装置间的聚氯乙烯电缆更换为钢芯铝绞线,并将传统的人工操作接线装置改为自动接线装置,有效解决了电缆易受潮、遭受机械损伤、电气距离不足、易老化等问题。改造方法安全、简单、有效、经济可靠。改造后,2014年覆冰期该线路地线融冰实施6次,均获得了成功,地线融冰成功率得到保证。

The reason of an unsuccessful event of ice melting by ground wire in extra-high voltage transmission line is analyzed to ensure the success rate of ice melting by ground wire. By the analysis of breakdown characteristics of the ice melting connection cable and the internal anatomic examination, it is considered that the connection cable was broken down because of the damp, mechanical injury, insufficient electrical distance and aging and so on, which caused the unsuccessful ice melting by ground wire. By using composite post insulator as the support, replacing the PVC cable between the ground wire and the ice melting connection device by the aluminum conductor steel reinforced wire and replacing the traditional manual operating connection device by automatic connection device, cable problems such as easy damping, mechanical injury suffered, insufficient electrical distance and easy aging and so on are solved. The modification method is safe, simple, effective and economic and reliable. After the modification, 6 times of the ice melting by ground wire for the line during the ice covering stage has been implemented all of which are successful, the success rate of the ice melting by ground wire is guaranteed.