白鹤滩±800kV特高压直流送出线路的雷击闪络率仿真计算

Simulation of Lightning Flashover Rate of ±800kV UHVDC of Baihetan Hydropower Transmission Line

雷击闪络是威胁白鹤滩±800kV特高压直流送出线路安全稳定运行的重要原因之一。为了准确校核白鹤滩-江苏±800kV特高压直流输电线路的雷击闪络率并指导工程线路防雷设计,首先分析了白鹤滩水电送出工程沿线的地形、气象分布特征及各区域电网的雷电故障统计情况,推荐了白鹤滩-江苏±800kV线路全线的雷击闪络率设计参考值。而后,基于电磁暂态仿真程序(EMTP)和电气几何模型法(EGM)对白鹤滩-江苏±800kV线路全线的雷击闪络率进行了综合仿真分析,确定了不同地形、塔型、地面倾斜角、接地电阻对雷击闪络率的影响,并结合沿线工程条件提出了全线及各段的雷击闪络率。最后,综合评估了现有的防雷设计方案,研究了进一步优化线路雷电性能的方案及措施。

Lightning flashover is one of the important reasons that threaten the safe and stable of operation of the±800 kV UHVDC transmission line from Baihetan to east.In order to check the lightning flashover rate accurately of Baihetan-Jiangsu±800 kV UHVDC transmission line and guide the lightning protection design of engineering,this paper first analyzes the distribution characteristics of topographical and meteorological and the statistics on lightning faults in each regional power grids along the Baihetan hydropower transmission line.The reference value of lightning flashover rate design for the entire line of Baihetan-Jiangsu±800 kV transmission line is recommended.Then,the comprehensive simulation analysis of the lightning flashover rate of the Baihetan-Jiangsu±800 kV transmission line is carried out based on Electro-Magnetic Transient Program(EMTP)and Electrical Geometry Model Method(EGM).The impacts of different topography,tower type,ground slope and grounding resistance on lightning flashover rate are analyzed,and the lightning flashover rate of the whole line and each section is calculated by combining with the engineering conditions along the line.Finally,the existing lightning protection design scheme is comprehensively evaluated,and the schemes and measures to further optimize the lightning performance of the line are discussed.