针对输电线路的雷电绕击问题，阐述了发生雷电绕击的原因，研究了防止绕击雷的方法。结合江西省输电线路的运行经验，分析了JG及ZGUT型铁塔绕击跳闸的原因，提出了防止JG及ZGUT型铁塔绕击跳闸的新措施。研究表明，在JG及ZGUT型铁塔的导线悬挂点横担上安装TH型避雷针，可以减少JG型铁塔的中相跳线保护角和ZGUT型铁塔的中相导线保护角，大幅度降低雷击故障跳闸率。

The reasons of shielding failure in transmission line were investigated, as well as the method of lightning shielding failure prevention. Based on operation experiences of transmission line in Jiangxi Province, the reason of shielding failure trip of JG and ZGUT type tower were emphatically analyzed, and a new measure was proposed to prevent shielding failure trip. The results show that TH-lightning rod installed on the cross arm at wire suspension point of JG and ZGUT type tower can reduce the shielding angle of mid-phrase jumper-line of JG type tower and that of mid-phase conductor of ZGUT type tower, which can greatly decrease the lightning failure trip rate.