基于统计方法的10kV配电线路雷电感应过电压闪络风险计算  

Probabilistic Risk Calculation of Flashover of the 10 kV Distribution Line Caused by Lightning Induced Overvoltage Based on Statistic Approach

作　　者：万忠兵[1] 蒋鑫源 王晨丞 张君胜[1] 蒲丽娟 WAN Zhongbing;JIANG Xinyuan;WANG Chencheng;ZHANG Junsheng;PU Lijuan(State Grid Sichuan Electric Power Co.Metering Center,Chengdu 610000,China;NARI Technology Co.,Ltd.,Nanjing 211106,China)

机构地区：[1]国网四川省电力公司计量中心,成都610000 [2]国电南瑞科技股份有限公司,南京210061

出　　处：《电瓷避雷器》2022年第6期92-97,共6页Insulators and Surge Arresters

基　　金：江苏省配电网智能技术与装备协同创新中心开放基金资助项目(编号:XTCX202003)。

摘　　要：雷击配电线路附近产生的雷电感应过电压极易导致线路发生闪络,需要合理计算线路绝缘闪络风险。本研究根据理论推导线路雷电感应电过压峰值概率密度函数,利用LIOV软件产生感应过电压数据拟合概率密度函数公式,考虑线路绝缘闪络的随机过程和线路交流电压的影响,求取线路雷电感应过电压绝缘闪络风险。研究结果表明:线路雷电感应过电压峰值随着雷电流幅值的增加、雷击点距线路垂直距离的减小而增大;线路雷电感应过电压峰值概率密度区间分布较好地服从对数正态分布特征;线路发生单相闪络、两相闪络的概率随着雷电感应过电压幅值的增加呈现先增大后减小的趋势,发生三相闪络的概率则逐渐增大至100%;同一临界闪络电压下,线路发生三相绝缘闪络的风险最高,单相绝缘闪络风险其次,两相绝缘闪络风险最低。线路交流电压对线路绝缘闪络风险的影响不能忽视。有必要加强线路绝缘水平以提高对雷电过电压的抵御能力。There exists a high risk of line insulation flashover when overhead distribution lines are exposed to lightning induced overvoltages,so it is necessary to calculate probabilistic risk of flashover of the distribution line.The formula of probability density functions of lightning induced overvoltage was derived by means of statistic approaches and LIOV code.Considering the random process of line insulation flashover and the influence of line AC voltage,the insulation flashover risk of line lightning induced overvoltage is calculated.Research results show that:the rise of peak lightning current or decreasing of vertical distance from lightning strike point to the overead line result in an increase of lightning induced overvoltage.It canbe observed that the histogram of peak lightning induced overvoltage follows a lognormal distribution well.The probability of single-phase flashover or two-phase flashover increases first and then reduces with increase in the magnitude of lightning induced voltage while the probability of three-phase flashover increases to 100%gradually.The average risk of three-phase flashover is highest,followed by the risk of single-phase and then two-phase flashover.The effect of AC voltage on probabilistic risk of flashover can not be ignored and line insulation level should be strengthened to enhance the ability to resist lightning overvoltage.

关 键 词：配电线路 闪络 雷电 感应过电压 交流电压 统计方法 

分 类 号：TM863[电气工程—高电压与绝缘技术]