摘要
±500kV江城线路自投运以来平均年雷击跳闸率为0．370次／km·年，84．2％发生在正极性。利用湖南雷电定位系统数据库，以±500kV江城线故障杆塔为抽样点，对±500kV江城线线路走廊的雷电活动参数进行了统计和分析，认为按边长为20km进行雷电流密度计算是合适的。沿线路走廊地闪密度存在较大的差异，但雷电流幅值分布规律没有明显的差异，雷电流幅值中值电流分布在19．5～24．6kA之间。采用规程法、多波阻抗法、回路法计算表明绕击是±500kV江城直流线路跳闸的主要原因。
Average lightning failure trip ratio of ±500 kV Jiang-Cheng HVDC is 0. 370 time per 100 km · year, in which 84. 2% happened at positive pole. Based on databases of Hunan lightning location system and sampling data from Jiang-Cheng fault tower, lightning movement parameters of 500 kV Jiang-Cheng transmission line corridor were statistically analyzed and the resuits indicated that it is appropriate to set the length of side at 20km. Lightning densities of line corridor can vary much, but lightning current magnitude distributions are similar. Middle current of lightning magnitude is between 19.5 kA and 24.6kA. Calculation results from rule method, multi-surge impedance method, and circuit method showed that shielding failure is the main cause for Jiang-Cheng HVDC lightning failure.
出处
《湖南电力》
2009年第5期36-41,共6页
Hunan Electric Power
关键词
±500
kV江城线路
耐雷水平
雷击跳闸率
绕击
±500 kV Jiang-cheng HVDC
lightning withstand level
lightning failure trip ratio
shielding failure
