粤北地区架空线路自然覆冰形态现场观测研究

Study on Field Observation for Natural Icing Form on Overhead Lines in Northern Guangdong Area

现场观测了粤北地区典型输电线路的覆冰情况,对杆塔的覆冰厚度、冰凌长度及数量、冰密度进行测量,研究了导线和绝缘子的覆冰形态及其与杆塔高度、绝缘子电场电位、绝缘子悬挂方式和位置等的关系。结果表明:该地区覆冰透明,覆冰水电导率均小于15μs/cm,冰密度为0.695～0.9 g/cm3,为雨凇;同一杆塔不同高度的覆冰形态不同;覆冰时导线上表面冰较厚,融冰时下表面冰较厚且有冰凌;地线下表面几乎无冰棱;绝缘子串高压端的覆冰比低压端严重;绝缘子的覆冰较杆塔和导线稍严重;插花串的使用可有效减少绝缘子片间桥接;不同相绝缘子的覆冰无差别;冰棱外翘现象较普遍,出现较随机,是电场和微环境风等因素综合作用的结果。

According to field observation for icing on typical transmission lines in northern Guangdong area and measuring da- ta about icing thickness, ice length and numbers, ice density, this paper studies relationship between icing forms of conduc- tors and insulators and tower height, electric potential of insulators, suspension ways and position of insulators. The result shows that icing in this area is a kind of glaze which is transparent and electric conductivity of the icing water is less than 15 μs/cm while the ice density is 0. 695~0.9 g/cm3. It also indicates that icing forms on the same tower but at the different height are different. On the upper surface of conductor, the ice is rather thick when happening icing while melting it is com- paratively thick on the lower surface. Meanwhile, there is no ice on the lower surface of the ground wire, icing at the high voltage terminal of insulator chain is more serious than the low voltage terminal, icing on the insulator is a little serious than that on the tower and conductor, utilization of flower arranging string can effectively reduce bridge connection between in- sulator pieces, icing on insulators with different phase is indistinguishable and upwards of ice is comparatively common which occurs randomly as a result of comprehensive role of electric field and micro environmental wind.