In order to make full use of the efficiency of composite material tower,it is studied to cancel the overhead grounding wire and downward leading wire to form fully insulated tower.Considering loss of discharging path when insulated tower is stroked by lightning, overvoltage caused by resulting intruding wave may do damage to equipment in substation, iron tower is proposed to be used in inlet line to relieve the overvoltage.Lightning withstanding levels of insulated tower and inlet line iron tower are simulated by ATP-EMTP, and the impact of lightning intruding wave on inlet line iron tower and substation, and the necessity of arrester is also studied.The results show that when arresters are not installed, the lighting intruding wave overvoltage(LIWOV) caused by lightning current of 9 kA on 110 kV insulated tower could result in flashover of inlet iron towers and about 800 kV overvoltage on a typical 110 kV substation, while LIWOV withstanding level of iron tower is improved up to about 40~45 kA lightning current and consequential overvoltage of less than 300 kV stressing the substation after installing arresters, which fulfills the requirements of the standard.%为充分发挥复合材料杆塔效能,研究取消架空地线和接地引下线,形成全绝缘杆塔;考虑绝缘杆塔失去原有泄流路径,雷电过电压沿导线传播可能危害到变电站设备,在进线段采用铁塔以增加雷电侵入波的泄流.通过ATP-EMTP仿真计算110 kV复合材料绝缘杆塔和进线段铁塔的耐雷水平,研究雷电侵入波对进线段铁塔及变电站设备的影响和在铁塔安装避雷器的必要性.结果表明:不安装避雷器时,110 kV绝缘杆塔线路段由幅值9 kA的雷电流造成的过电压可导致进线段铁塔闪络,传播至变电站的过电压幅值约800 kV;在进线段两端铁塔三相安装线路避雷器,可有效抑制雷电侵入波过电压,进线段铁塔可耐受40~45 kA雷电流侵入波过电压,同时110 kV变电站内过电压低于300 kV,满足规程要求.
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