绝缘导线防弧含检修接地功能金具的研制

根据10kV架空绝缘导线易遭雷击断线的机理,结合线路检修接地保护的需要,研制一种集穿刺式雷击放电间隙和检修接地保护功能的金具,雷电正、负极性冲击放电试验结果表明:在15cm、16cm和18cm放电间隙下,P20、P15、PS15型绝缘子每次放电均发生在穿刺燃弧金具端电极与接地端电极间,使工频电弧弧根固定或疏导至穿刺燃弧金具或引弧棒上燃烧并断弧。保证遭雷击时绝缘导线不击穿、熔断或沿绝缘子面闪络接地。将穿刺燃弧(含检修接地保护功能)金具安装在距绝缘子绑扎处外负荷侧40～50cm绝缘导线上,调整好上下电极距离,能有效地杜绝绝缘导线遭雷击时断线隐患,又可在线路检修中挂设检修接地线,另外穿刺牙齿采用T2紫铜材料,直接相嵌浇铸在上下铝合金压板内,其穿刺咬合力度远比整体铝合金浇制的穿刺线夹咬合接触优。

Development of Line Fitting for Insulated Conductor With Arc-protection and Grounding at Live Work

Due to necessity of protective grounding at line overhaul in case of overhead isolated conductor braekage caused be thunder strike a line fitting having puncture spark gap and grounding function at line overhaul was developed lightning flashover test at both positive and negative polarity shows that with the spark gap of 15 cm,16 cm and 18 cm,every flashover on insulator P20,P15 and PS15 occurs between the puncture spark gap and grounding electrode,leading the power frequency flashover are root to the puncture arcing fitting or to the arcing rod and extinction afterward,thus the breakage,puncture or flashover grounding along insulator surface can be avoided.The fitting shall be fixed at insulated conductor,40～50 cm away from tie-wire-groove of insulator.With adjusted gap space it can effectively avoid potential danger of conductor breakage at lightning strike,and connect grounding wire at line overhaul.The puncture teeth were made of T2 copper,embedded in aluminium die-pressed clamp by easting,which have a higher gripping force than that made of aluminium casting.