导线电压对其雷电绕击耐雷性能的影响

雷电绕击是高压线路的雷击事故的主要因素。为了提高压输电线路绕击耐雷性能,考虑雷击大地、避雷线和导线的差别,分析了导线工作电压对击距的影响,推导出最大击距的计算公式,从而得到最大击距与雷电的正负极性、导线电压的大小及正负极性、击距系数的关系,并以实例论证了可以通过平衡塔高、地面倾角、击距系数和保护角的取值有效地提高线路的绕击耐雷性能。

Influence of Conductor Voltage on Its Lightning Protection Performance when Shielding Failure Occurred

Shielding failure is a main factor leading to lightning faults of HV transmission lines. Considering the difference among lightning on the ground, lightning on rods, and lightning on lines, and analyzing the influence of conductor voltage on striking distance, this paper deduces the calculation formula for maximum striking distance, resulting in the relationship of the maximum distance with the polarity of lightning, the size and polarity of line voltage and the coefficient of striking distance. Case study shows that lightning shielding performance of HV transmission lines can be effectively improved by balancing the values of tower height, inclination angle, striking distance coefficient and shielding angle.