采用涡流自热环防止输电线路冰雪灾害的方法研究

Study on Preventing Icing Disasters of Transmission Lines by Use of Eddy Self-Heating Ring

输电线路覆冰现象对电网的安全运行造成极大危害,国内外一直在探索和研究各种对于输电线路防冰止雪的有效方法和技术措施。该文根据输电线路导线覆冰积雪的形成过程,提出在导线上分段加装铁磁复合材料制成的涡流自热环,使其在导线传输电流产生的磁场下产生电磁热损耗,实现导线不停电自动除冰方法。该文通过磁热分析,对不同传输电流下涡流自热环的发热功率特性进行了计算;同时通过对导线除冰过程热平衡的分析,计算出不同风速、不同温度条件下导线的临界除冰功率。在人工气候室内开展LGJ-400/35导线的涡流自热环防/除冰试验。试验结果表明,间隔布置的涡流自热环可以明显抑制导线覆冰的形成,除布置处完全融冰外,可使整段导线的覆冰质量减少18.38%~30.61%。理论和试验结果表明,对微地形、微气象地区等电网小范围重冰区而言,涡流自热环是一种简单、有效的不停电导线防冰除冰措施。

Ice accretion on transmission lines posts great threat to the operation of power grid.Various new methods and technical measures have been exploring to achieving anti-icing and de-icing of transmission lines.In this paper,self-heating rings made of ferromagnetic material are fixed on the conductor to achieve anti-icing without power outage.Exposed in the magnetic field and generated by the transmission current,strong magnetic field will be induced in self-heating rings and lead to magnetic heat loss for anti-icing.In this paper,the thermal power characteristics of the self-heating rings with different transmission currents are calculated by magnetothermal analysis.At the same time,the critical de-icing power of conductor with different wind speed and temperature conditions is calculated by analyzing the thermal conservation.Anti-icing test of LGJ−400/35 conductor with self-heating rings is performed in artificial climate chamber.The results show that self-heating ring can reduce the ice accretion on conductor obviously.There is no ice formed on the conductor where self-heating rings fixed.Furthermore,the total ice mass on conductor decreased 18.38%~30.61%in test condition.Therefore,for the transmission line in heavy icing areas,the use of self-heating rings is a simple and feasible way to preventing icing disaster.