不同时期雪中的盐分迁移现象及环境温度的影响研究

Study on Salt Migration Phenomena in Snow during Different Periods and the Effect of Ambient Temperature

在寒冷地区,绝缘子上的覆冰会严重影响绝缘性能,对电网的安全运行造成危害。雪作为一种大气覆冰类型,会降低输电线路外绝缘性能,严重时可能引发绝缘子闪络事故。造成绝缘子绝缘性能下降的一个重要因素是雪中的盐分。在雪融化时,较高的盐分会导致融雪水电导率增加,极易引发绝缘子闪络。在人工气候室内对玻璃板以及玻璃绝缘子进行覆雪试验,并在覆雪期、储雪期以及融雪期内进行分层测量,关注不同覆雪时期内的盐分迁移现象以及对环境温度造成的影响。试验表明,在覆雪期内湿雪会发生少量的盐分迁移,在储雪期内盐分迁移很难发生,而在融雪期内盐分迁移现象很明显,且与温度密切相关。

In cold climate regions, atmospheric icing on insulators setaously auecung msuia,,- t,-l- formance and it is harm to the safe operation of the power grid. As one kind of atmospheric icing, snow can reduce the insulation performance of transmission lines and may cause insulator flashover accident in serious case. Salt in snow is one of the most important factors causing the reduce of insulation performance. When snow melts, high salt content may cause the increase of the conductivity of melt water and easily triggers the flashover of insulators. This article focuses on the salt migration phenomena in snow during different periods and the effect of ambient temperature by conducting tests on glass plate and insulators in the climate chamber and carrying out stratified measurements in snow cover period, snow storage period and snowmelt period. The results showed that the salt migration of wet snow is slight during snow cover period and it hardly occurs in snow storage period. While in snowmeh period, it is remarkable and closely related to the temperature.