河南电网输电线路舞动的气象要素指标研究

Study of Meteorological Indices for Transmission Line Galloping in Henan Power Grid

利用2009—2010年河南省3次输电线路舞动过程的探空站资料和地面气象站观测资料,分析了输电线路舞动的气象要素特征,得出输电线路舞动的气象要素指标:(1)700~850 hPa存在≥0℃的暖层,其下存在<0℃的冷层。(2)700 hPa以下空气接近饱和,温度和露点温度的差值≤2℃。(3)地面温度-4~1℃,风速≥3 m·s^(-1),相对湿度≥70%。利用1998年至今的探空数据和地面气象站观测数据,以及2015年11月至今的模式数据,对上述指标进行了检验。最后以2015年11月22—24日河南电网的舞动过程为例,采用上述指标绘制了舞动分布图,发现利用该指标预报的舞动格点涵盖了电网实际监测到的发生舞动的杆塔,该指标具有一定的适用性。

Using data of power transmission line galloping （which happened 3 times from 2009 to 2010） in Henan Province and observations from representative stations, characteristics of line galloping are analyzed and meteorological indices for transmission line galloping are obtained. It shows that transmission line galloping will happen when the following conditions are satisfied： （1） A cold layer exists near 850 hPa where the temperature is less than -4℃ and a layer warmer than 0℃ exists below the cold layer. Alternatively, a layer warmer than 0℃ near 700-850 hPa and a cold layer exists below the warm layer; （2） the difference between temperature and dew point temperature below 700 hPa is less than 2℃ ; （3） the surface temperature ranges between -4℃ and 1℃, the wind speed is greater than 3 m · s -1 and the relative humidity is greater than 70 %. Finally, the meteorological indices are used to draw the galloping distribution map for the galloping process monitored in 22-24 November 2015 in Henan Province. It is found the galloping grids predicted with the indices can cover the galloping monitored tower-poles. Thus, the indices are reasonable and applicable.