摘要
形成干区是污闪发生的前提条件之一,为此重点从热的角度分析了干区的形成过程。用两端带有铝电极的矩形玻璃板模拟实际绝缘子,用红外热像仪拍摄了雾室中绝缘板表面干区形成中的温度分布变化,同时用泄漏电流测量系统实时记录了泄漏电流的变化。最后,将温度分布变化和泄漏电流趋势联系在一起,细致地分析了干区的形成过程,并得到了干区形成过程中的一些规律:加压之初,污层表面温度均匀稳定升高;干区形成之前污层表面会出现持续的高温区,局部干区首先形成在高温区;局部干区向完整干区的发展在温度分布上表现为高温在污层的贯穿;完整干区形成后,污层总体温度下降,但是干区呈现扩大趋势;干区达到稳定后,湿区温度降低为环境温度,干区依旧维持高温且温度由干区中心向两侧递减。因此,干区的形成不仅仅是一个电的过程,同时也是一个热的过程。
The formation of drybands is one of the preconditions of pollution flashover. We analyzed this formation from perspective of heat. A rectangular sheet of glass with electrodes on its two sides was used to simulate insulator, and an infrared camera was used to record the temperature change of the insulation surface during the process of dryband for mation. In the meantime, current was also recorded. Finally, the temperature distribution and the leakage current variation were combined to clarify the process of formation of drybands. Some conclusions are drawn as follows： the temperature of the pollution layer increases evenly and stably in the initial period of voltage application; some high temperature zones will form before a dryband is formed and the dryband develops in this location initially; the process of a local dryband developing into a complete dryband corresponds to the breakthrough of high temperature areas along the insulation sur face; after the formation of a complete dryband across the insulation surface, the overall temperature decreases and the dryband expands in width; the temperature distribution of the pollution layer gradually becomes stable, and the tempera ture of the wet area decreases to the ambient temperature while the temperature of the dryband remains high; temperature is the highest along the centre line of the dryband and it decreases toward either side. Therefore, it is concluded that the formation of dryband is not only an electrical process, but also a thermal one.
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2014年第1期138-146,共9页
High Voltage Engineering
基金
国家重点基础研究发展计划(973计划)(2009CB724503)~~
关键词
污闪
干区
温度
红外热像仪
泄漏电流
平板模型
人工污秽试验
pollution flashover
dry-band
temperature
infrared camera
leakage current
flat plate model
artificial pol-lution test
