摘要
讨论了经典的电气几何模型(EGM),在此基础上提出了3点改进建议。计算中采用IEEE推荐的击距公式,引入系数ksg描述雷击地线和雷击地面击穿强度的不同,用暴露距离计算雷电绕击率和绕击跳闸率。分析了ksg取值对计算结果的影响。利用改进的计算方法、分别计算了地面倾角、避雷线保护角和环境温度对线路绕击跳闸率的影响。结果表明,当ksg减小、地面倾角增大、避雷线保护角增大、温度降低时,绕击跳闸率增大。
This paper discusses the classical electric geometry method and improves it in three aspects. In the improved model, ＂strike distance＂ is calculated with the expression recommended by IEEE, a coefficient ksg is introduced to describe the difference of electric intensity between lightning stroke on the transmission line and the ground, and the ＂uncovered distance＂ is adopted to calculate shielding failure flashover rate. Paper analyses the in- fluence of ksg on the calculated results. Making use of the improved model, the influence of some parameters to the flashover rate is calculated and analyzed. The results show that the flashover rate reduces with the reduction of ksg, increase of the obliquity, protection angle and, atmospheric temperature.
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2006年第3期42-44,共3页
High Voltage Engineering
关键词
输电线路
绕击
电气几何模型
击距
transmission line
shielding failure
electric geometry method（ EGM）
striking distance
