10kV绝缘架空线路避雷线的保护角选择

Discussion on the Shielding Angle of Ground Wire in 10kV Insulated Overhead Distribution Lines

10kV配电线路分布广泛,绝缘水平低,在雷电活动频繁的地区,雷害事故经常发生。随着配电网的绝缘化改造,雷击断线问题日益显著。介绍了避雷线防雷原理,架设避雷线时需要考虑的因素,保护角对避雷线的绕击率、耦合系数、雷击跳闸率的影响,结合一个实例介绍10kV绝缘架空线的避雷线保护角选择方法,并在EMTP中进行了仿真,验证其防雷效果,得出典型的单回水泥杆塔10kV绝缘架空线架设避雷线选取保护角的最佳方案为25°。

The 10kV distribution lines are widely distributed and the insulation level is low.In areas with frequent lightning activities,lightning accidents often occur.With the insulation transformation of the distribution network,the problem of lightning strikes is becoming more and more significant.The lightning protection principle of the lightning protection line is introduced.The factors to be considered when setting up the lightning protection line,the influence of the protection angle on the lightning protection rate,coupling coefficient and lightning trip rate of the lightning protection line.The method of selecting the lightning protection angle of the 10kV insulated overhead line is introduced with an example,and the simulation is carried out in EMTP to verify its lightning protection effect.It is concluded that the optimized scheme for choosing shielding angle is 25°for typical single loop 10kV cement tower insulated line insulated overhead line to equipped with a ground wire.