500 kV同塔双回交流输电线路绕击耐雷性能及防雷措施研究
Research on Shielding Lightning Performance and Lightning Protection Measures for 500 kV Double Circuit AC Transmission Lines on the Same Tower

500 kV架空输电线路分布较广，常常穿越海拔较高、气象环境恶劣或地理环境复杂的山区，因其特殊的走势分布，所以容易遭受雷击。架空输电线路的雷击相对于其他自然灾害引起的线路故障来说，比重较大。尤其在多雷区、土壤电阻率高、地形复杂的地段，雷电的危害更是突出。因此，保证500 kV架空输电线路安全稳定的运行，减少雷电对线路的危害就成了线路安全运行的关键条件，这也突出了输电线路防雷的重要性。在讨论输电线路的防雷方式时，要根据线路的具体情况来实行分析。在本篇论文中，我从两个方面来对线路防雷进行分析，第一个是对线路防雷起着重要作用的各种因素的讨论，包括杆塔高度对绕击耐雷性能的影响、地面倾角对绕击耐雷性能的影响、保护角对绕击耐雷性能的影响、导线排列方式对绕击耐雷性能的影响；第二方面是阐述输电线路对降低雷击采取的综合措施，包括架设旁路架空地线、减小保护角、可控放电避雷针、架设耦合地线等措施。最后，综合以上分析以及措施对各种防雷方式的效果及成本分析对本文进行总结，得出能有效防雷的小结。
500 kV overhead transmission lines are widely distributed and often pass through mountainous areas with high altitudes, harsh weather conditions or complex geographic environments. Because of their special trend distribution, they are prone to lightning strikes. Lightning strikes on overhead transmission lines have a larger proportion than line failures caused by other natural disasters. Especially in areas with many mines, high soil resistivity, and complex terrain, the hazards of light-ning are even more prominent. Therefore, ensuring the safe and stable operation of 500 kV over-head transmission lines and reducing the hazards of lightning to the line has become a key condi-tion for safe line operation, which also highlights the importance of lightning protection for trans-mission lines. When discussing lightning protection methods for transmission lines, analysis should be carried out according to the specific conditions of the line. In this paper, I analyze the lightning protection of the line from two aspects. The first is the discussion of various factors that play an im-portant role in the lightning protection of the line, including the influence of the height of the tower on the lightning protection performance of the shielding strike, the influence of the ground inclina-tion angle on the lightning resistance of shielding strikes, the influence of the protection angle on the lightning resistance of shielding strikes, and the influence of wire arrangement on the lightning resistance of shielding strikes. The second aspect is to describe the comprehensive measures taken by transmission lines to reduce lightning strikes, including erecting overhead bypasses. Measures include grounding, reducing the protection angle, controllable discharge lightning rods, and setting up coupled grounding wires. Finally, this paper summarizes the above analysis and the effect and cost analysis of various lightning protection methods, and obtains a summary of effective lightning protection.