摘要
为进一步提高真空绝缘体沿面闪络电压,采用变压器油涂敷于真空绝缘体表面,实验研究了脉冲电压下油膜涂覆绝缘体的真空沿面耐压性能。实验结果表明:真空中油膜涂覆绝缘体首次沿面闪络电压和老练电压均有大幅度提高,但耐受电压与未涂覆绝缘体的耐受电压基本一致。根据实验结果结合真空沿面闪络二次电子崩理论和液体击穿二次电子崩理论,初步认为闪络发生在绝缘体与油膜交接面处,油介质的涂覆抑制了绝缘体表面二次电子崩的发展和解吸附气体的释放,提高了首次闪络电压和耐受电压,但较高的闪络电流释放的热量将可能在绝缘体表面形成固有闪络通道从而降低油膜涂覆绝缘体耐受电压,油介质的涂覆促使电极与绝缘体接触良好从而降低了闪络电压的分散性。该涂覆方法有希望应用于对真空无特殊要求的固体支撑结构来提高真空耐压性能,但油介质对真空的影响还有待进一步研究。
In order to improve the surface flashover voltage of insulator in vacuum, we experimentally researched insulator surface fiashover characteristics with transformer oil coating in vacuum under pulsed voltage. The results indicate that both first-flashover voltage and condition-flashover voltage are improved by coating transformer oil on insulator surface, but the hold-on voltage level is similar to that of insulator without coating. Moreover, we analyzed the flashover physical process and proposed that the secondary electrons avalanche and desorbed gases were limited by coating oil to improve the flashover voltage. According to the theory of secondary electrons avalanche in vacuum and in liquid, we proposed that the flashover occurred on the interface between the transformer oil and the insulator. The fixed flashover channel on the insulator surface may be formed due to the higher thermal of flashover current energy to decrease the hold-on voltage level. At the same time, the oil dielectrics could optimize the electrode and insulator contacting points to reduce the flashover voltage data discrete. This coating method may be used in pulsed power device to increase the vacuum insulator performance without special requirements of vacuum, but the influence of oil coating layer would be researched continually.
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2017年第6期1995-2000,共6页
High Voltage Engineering
基金
国家自然科学基金(51307155
51277168)~~
关键词
绝缘体
油膜涂覆
沿面闪络
二次电子崩
解吸附气体
变压器油
闪络电流
insulator
oil coating
flashover
secondary electron avalanche
desorbed gases
transformer oil
flashover current
