In order to better understand the probability distribution of space around the each lightning point and influences of ground wires protection angular of the 500 kV transmission line on the shielding performance, using the 500 kV typical transmission lines as examples, we established a model of reducing transmission line tower to simulate the shielding failure. The experimental results verify the superiority of the negative protection angle in the antishielding performance, and reveal that, the closer the transmission lines are, the more the strike is; from the central tower head to file, the probability of shielding failure increases first, then decreases. The research results provide a scientific basis for the design of lightning protection of 500 kV transmission lines.

为研究引起架空绝缘导线断线的原因,提出防雷击断线切实有效的措施,综合比较了目前国际国内的架空绝缘导线防雷击断线的措施后得出雷击断线主要是由于雷电过电压引起绝缘子闪络后的工频续流引起的,工程中应根据现场的实际情况、安装是否方便和经济性等因素,综合考虑确定防雷击断线的措施,目前主要是采用架设架空接地线、安装带间隙的避雷器和安装防弧金具等3种。