1000kV交流同塔双回输电线路导线脱冰跳跃特性

Ice-shedding Characteristic of 1000 kV AC Double Circuit Transmission Line on the Same Tower

导线脱冰会引起导线的剧烈运动,使导线跳跃上下摆动,将导致导地线间或导线档中空气间隙的减小,严重时引起闪络;特高压线路由于导线分裂根数较多,截面较大,其脱冰跳跃问题更为严重,特高压输电线路导线脱冰跳跃的考虑对于导线排列,杆塔选型,档距配置等都有重要意义。为此首先进行了单导线覆冰脱落模拟试验研究,研究了不同档距组合、不同脱冰方式下的导线脱冰跳跃规律。还通过计算机仿真的方法针对试验工况进行数值模拟,仿真计算与模拟试验的结果具有相同的规律性。建立了适用于1000 kV交流同塔双回输电线路导线脱冰跳跃分析的3自由度多档导线模型,分析了连续档数、档距组合、档距大小、导线机械参数因素对特高压同塔输电线路脱冰跳跃的影响。分析了15 mm覆冰情况下特高压线路导线脱冰跳跃水平。研究表明,在15 mm覆冰及以下时,特高压同塔双回输电线路相间导线不需要水平偏移,在导线发生脱冰跳跃时线路也能安全运行。

The rules of ice shedding characteristics were acquired by simulation tests, and various span configurations as well as ice shedding mode were taken into consideration. Furthermore, numerical computation was done according to the test conditions. Good agreement between the computational and test results was obtained which proves the validity of both the test and numerical methods. Then a 3DOF（degree of freedom） dynamic model of multi-span line suitable for analyzing UHV ice-shedding was presented. The influential factors including multi-span configuration, span length, number of spans per line section, and mechanical parameters of conductor are studied. The ice-shedding height of UHV was analyzed when the icing thickness was 15 mm. Results show that interphase conductors of UHV double circuit transmission line needn＇t have horizontal displacement at the condition of 15 mm ice thickness and below. When the ice shedding from the conductor happens, the lines can also work safely.