输电线路雷电防护技术研究(二):分析方法

Lightning Protection Study of Transmission Line,Part Ⅱ:Analysis Methods

防雷分析是对线路防雷性能和各种防雷措施效果进行评价的基础及防雷决策与设计的前提。为此,讨论了国内外输电线路防雷分析方法的发展状况及其存在的问题,特别研究了输电线路的雷电反击特性和绕击特性分析方法及其综合应用,提出了适当的线路防雷分析计算模型和方法。研究表明:在输电线路反击特性分析时,应建立充分反映输电线路雷电暂态特性的全波过程分析方法,绕击分析则应根据电压等级的不同选用电气几何模型、先导发展模型和分形模型。防雷分析应充分考虑微地形及雷电区域特性的影响,综合评估不同区域线段的防雷特性。

Design is the key of lightning protection of transmission lines, and lightning protection analysis is the base to estimate the lightning protection behaviors of transmission line and the effect of lightning protection measures for transmission line. We mainly discussed the development states and the existed problems in lightning protection analysis of transmission line in the world, presented the analysis methods on the lightning baekflash and shielding failure of transmission line and their comprehensive applications, and proposed the suitable models and methods for lightning protection analysis of transmission line. The whole waveprogress analysis model should be applied to calculate the lightning transient characteristics of transmission line when the lightning strikes the tower or the overhead ground wires of transmission line; different analysis methods, such as electrogeometric method, the leader propagating model and the fractal model, should be used to calculate the shielding failure behaviors of transmission line. The lightning protection analysis of transmission lines should consider the micro-typological characteristics and the area difference of lightning parameters along transmission line, and comprehensively estimate the lightning protection behaviors of transmission line sections.