架空线路雷电感应电压的宏模型及跳闸率计算

Macromodel of Lightning Induced Overvoltages on Overhead Lines and Calculation of Lightning Flash-over Rate

架空配电线路绝缘水平低,极易遭受雷击产生雷电过电压,从而造成供电中断影响广大人民的生产和生活;对于10 k V架空配电线路,由雷击引起线路闪络或故障的主要因素是感应雷过电压,因此,对架空配电线路感应雷过电压的研究具有十分重要的意义。为了提高配电线路的安全可靠性并对线路防雷设计提供有价值的参考依据,基于Agrawal场线耦合模型建立了一种计算感应雷过电压峰值的宏模型,并与时域有限元方法进行了对比验证;结合电气几何模型及蒙德卡罗法对华北地区10 k V架空输电线路进行感应雷跳闸率计算。

Because of low insulation level,overhead distribution lines are easy to be damaged by lightning,which may cause lightning overvoltages and power interruption. For the 10 k V overhead distribution lines,the main factor of flashover or fault caused by lightning is lightning induced overvoltages. To improve the safety and reliability of overhead distribution lines and provide reference for lightning protection design,this paper established a macro-model on the basis of the Agrawal field-to-line coupling model. The new model was applied to calculate the peak value of lightning induced overvoltages( LIOVs) on overhead lines and compared with time domain finite element method( TDFEM). Finally,the induced lightning flash-over rate of 10 k V overhead lines in north China was calculated by the proposed model,the electro-geometrical model and Monte Carlo method.