基于蒙特卡罗法的500kV同杆双回路绕击跳闸率计算和分析

根据雷击现象随机性大的特点,选用蒙特卡罗法并结合电气几何模型对500 kV同杆双回线路的绕击跳闸率进行计算。在计算中,以暴露弧为0时对应的雷电流作为雷电的最大绕击电流,并分析了地面倾角、杆塔结构等因素对各导线绕击跳闸率的影响。计算结果表明,随着地面倾角增大,绕击跳闸率先增大后减小;绕击跳闸率随避雷线横担增长而减小;对同杆双回输电线路,应分别计算各导线的绕击跳闸率,而不宜仅仅求得总绕击跳闸率。这样可以对绕击跳闸率较高的导线加强绝缘,以提高线路的耐雷水平。

Calculation and analysis of 500kV double-circuit on the same tower shielding failure trip-out rate based on Monte Carlo Method

Since strike is highly random,this paper adopts Monte Carlo Method combined with electro geometric model to calculate 500 kV double-circuit on the same tower shielding failure trip-out rate.In calculation,the maximum shielding failure current is the corresponding lightning current when exposure arc is 0.The paper also analyzes how dip angle and tower structure influence shielding failure trip-out rate.Calculation proves that with the increase of dip angle shielding failure trip-out rate increases at first and then reduces;shielding failure trip-out rate reduces with the increase of lightning wire＇s cross arm;as for double-circuit transmission line on the same tower,shielding failure trip-out rate should be calculated separately.By this method,the conductor of high shielding failure trip-out rate could be strengthened on the aspect of insulation to enhance lightning resistance of transmission line.