等效扩径导线与分裂导线覆冰比较

Comparison of Icing Between Equivalent Expanded Diameter Conductor and Bundle Conductor

覆冰地区的输电线路覆冰将对电网的安全稳定运行产生严重威胁,甚至导致大面积停电。考虑到扩径导线具有覆冰少、表面电场强度低等优点,在覆冰地区采用扩径导线有望降低输电线路的冰灾事故。为此结合导线覆冰形成机理,在雪峰山野外站对导线覆冰与其直径的关系进行了十余年的观测统计分析,并对扩径导线替代n(n=4,6,8)分裂导线的3种方案的覆冰特性和机械特性进行对比研究。结果表明:导线覆冰与其直径的关系满足导线直径越大,水滴碰撞率越低,覆冰量越少;与普通分裂导线相比,采用有效导电面积相同的扩径导线代替分裂导线,其传输能力相同,但覆冰量减少约60%~70%,提高了输电线路的抗冰强度,且其机械特性也优于多分裂导线。该研究结果可为覆冰地区的高压、超高压以及特高压输电线路采用扩径导线替代分裂导线实现冰灾的有效防治提供新思路和数据参考。

Transmission line icing in icing areas will pose a serious threat to the safe and stable operation of power grids,and even lead to large-scale blackouts.The expanded diameter conductor has the advantages of less icing and low surface electric field intensity,thus the use of expanded diameter conductor in icing area is expected to reduce ice disaster accidents on transmission lines.Therefore,combined with the formation mechanism of icing on transmission lines,the relationship between the icing on transmission lines and its diameter has been observed and statistically analyzed for more than ten years in the Xuefeng Mountain field station,and the ice characteristics and mechanical properties of the expanded diameter conductor which replaces n(n=4,6,8)bundle conductor(three programs)are comparatively studied.The results show that the larger the diameter of the conductor is,the lower the rate of water droplet collision will be,and the less the amount of ice coating will be.Compared with ordinary bundle conductors,when the same effective conductive area of expanded diameter conductor instead of bundle conductor is utilized,its transmission capacity is the same,but the amount of ice is reduced by about 60%to 70%,which improves the ice resistance of the transmission line,and its mechanical properties are also better than those of multi-split conductors.The results of this study can provide new ideas and data references for the use of expanded diameter conductor to replace bundle conductors in high-voltage,extra high-voltage(EHV)and ultra high-voltage(UHV)transmission lines in icing areas to effectively prevent ice disasters.