摘要
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 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.
出处
《电力建设》
2010年第6期6-10,共5页
Electric Power Construction
基金
浙江省电力设计院科研项目(220kV定海-甬东双回输电线路工程大跨越防雷设计研究)