玻璃陶瓷表面浅陷阱分布对其真空沿面闪络特性的影响

长期以来沿面闪络现象一直制约着真空绝缘系统的整体性能，极大地限制了高压电真空设备的发展进程。针对一种具有良好加工性能及表面耐电特性的低熔点可加工微晶玻璃陶瓷引入真空绝缘的背景，研究了不同制备工艺的可加工陶瓷试品在进行表面氢氟酸处理前后其电学特性的变化。利用表面电位衰减法测量了材料表层陷阱分布，分析了表面酸处理对其陷阱分布的影响；采用光电结合的方法，测量了不同表面处理的材料在真空中的表面耐电情况，分析了材料表面陷阱的密度和能级对闪络特性的影响。发现玻璃陶瓷材料表面存在的玻璃相结构是造成存在大量浅陷阱的重要原因，而浅陷阱对沿面闪络特性造成不利影响。得知通过氢氟酸处理可以腐蚀掉材料表面的玻璃相结构，从而降低浅陷阱密度，进而明显提高材料表面闪络的稳定性和降低分散性。

Effects of Surface Shallow Trap Distribution on Flashover Characteristics of Glass Ceramic in Vacuum

Surface flashover phenomena in vacuum restrict the overall performance of insulation system, which seriously limits the development of high voltage electro-vacuum devices. On the basis of the low melting temperature machinable glass ceramic for vacuum insulation system, which has excellent machinable performance and good surface electrical capability, the surface electrical properties of samples with different preparation technologies were investigated before and after treated with hydrofluoric acid. By employing the surface potential decay method, its surface trap distribution was measured, and the influence of acid treatment on the surface trap distribution was analyzed. Based on the concurrent optical and electric measurements, the surface electric strength of samples with different treatments was tested in vacuum, and the influence of surface trap density and energy on flashover performance was analyzed. It shows that, the glass phase on the surface of glass ceramics is an important factor for the largely existing shallow traps, and the shallow traps bring disadvantage in the flashover characteristics. By eroding off the glass phase in the sample with hydrofluoric acid treatment, the shallow traps can be reduced, thus its flashover stability can be greatly improved and its scattering phenomenon is significantly reduced.