定海-甬东特大跨越线路段的耐雷性能

为确保定海—甬东特大跨越输电线路的耐雷可靠性，采 用电气几何模型与电磁暂态程序计算其绕击、反击跳闸率，并 分析了绝缘配置、避雷线保护角、杆塔接地电阻和线路型避雷 器对线路耐雷性能的影响。计算结果表明，对于该大跨越线 路，绕击是雷击跳闸的主要原因，杆塔的接地电阻对反击耐雷 水平影响很小，且加装线路型避雷器后能显著降低雷击跳闸 率。提出了适合该特大跨越线路的防雷方案，即避雷线采用 0°保护角设计，并在最边相导线上安装避雷器。

Lightning Performance of the Dinghai-Ningbo East Extra-large Span Transmission Line

Lightning performance is calculated and analyzed for the Dinghai-Ningbo East large-span transmission line with EGM（electro-geometrical model） and EMTP（electro-magnetic transient program）.The effects of insulation coordination,shielding angle,grounding resistance and line arrester are also discussed in detail.The results show that,for the large-span transmission line with high towers,shielding failure is the main cause for the line trip,while the grounding resistance has little effect on the withstanding level of back flashover and the line arrester can substantially reduce the lightning trip-out rate.Finally,a lightning protection scheme of 0°shielding angle with installation of line arrester is proposed.