不同类型绝缘子表面移动激光除冰性能及热损伤特性研究

Investigation into the performance and thermal damage characteristics of mobile laser deicing on various insulator surfaces

中文关键词: 绝缘子  激光除冰  热损伤  除冰效率  除冰策略

英文关键词: insulator  laser de-icing  laser damage  numerical simulation  deicing efficiency  deicing strategy

中文摘要:

      激光因能够远距离、无接触地快速清除覆冰，并且能够实现带电作业，在绝缘子覆冰清除领域有着广阔的应用前景。然而，激光的高能量密度容易使绝缘子发生热损伤，同时绝缘子激光除冰的效率和安全性受绝缘子类型及激光参数影响极大。为此，本文针对不同类型绝缘子在表面移动激光辐照下的除冰性能及热损伤特性开展数值研究，拟通过揭示覆冰层对绝缘子表面温度特性的影响以及激光参数调控绝缘子除冰性能的作用规律，为高效、安全激光除冰策略的制定提供理论支撑。研究结果表明：针对陶瓷、玻璃以及复合绝缘子，绝缘子表面的覆冰层均能显著削弱激光对其内部结构的热损伤。激光功率密度的增加在强化三类绝缘子除冰效率的同时，也会导致绝缘子表面最高温度的上升，使得绝缘子发生热损伤的风险增加。激光光斑移动速度的加快能够有效提升陶瓷和玻璃绝缘子表面覆冰的融化速度，但对复合绝缘子表面覆冰清除效率的影响较小。所以，在优化绝缘子激光除冰策略时，适度提高激光光斑的移动速度具有重要作用。此外，对于绝缘子覆冰时形成的冰棱，无论其是否形成桥接，皆可通过降低激光功率密度，依靠低功率激光在冰棱顶部产生的应力来破坏其结构，从而使冰棱在重力作用下自然脱落，这一发现为绝缘子除冰提供了新的思路和方向。

英文摘要:

      Laser deicing has the advantages of high energy, good directivity and high long-distance transmission efficiency. However, it is easy to cause thermal damage to insulators when using laser to deice them. In this paper, ANSYS software is used to study the thermal damage characteristics of insulators and the efficiency of laser deicing. The results show that the ice coating on the insulator surface has a certain protective effect on its internal structure. With the increase of the power density of the moving laser, the ice melting speed of the three types of insulators increased, but at the same time, the surface temperature also increased. It is worth noting that the melting speed of the surface ice covered by ceramic and glass insulators will increase with the acceleration of the laser moving speed, while the melting speed of the surface ice covered by composite insulators is relatively insensitive to the change of the laser moving speed. Therefore, when optimizing the deicing scheme of insulator surface, it is worth considering to moderately increase the moving speed of laser. In addition, for the icicle formed when the insulator is covered with ice, regardless of whether it forms a bridge, when the moving laser spot acts on the position of the icicle, by reducing the laser power density, the stress generated by the low-power laser on the top of the icicle can be relied on to destroy its structure, so that the icicle will naturally fall off under the action of gravity. This discovery provides a new idea and method for insulator deicing.