Improvement of Surface Flashover Performance in Vacuum by Co-firing Mo/Al2O3 Cermets and Al2O3 Ceramics

被引：23

作者：

Li, Shengtao ^{[1
]}

Zhang, Tuo ^{[1
]}

Sun, Jian ^{[1
]}

Huang, Qifeng ^{[1
]}

Li, Jianying ^{[1
]}

机构：

[1] Xi An Jiao Tong Univ, State Key Lab Elect Insulat & Power Equipment, Xian 710049, Shaanxi, Peoples R China

来源：

IEEE TRANSACTIONS ON DIELECTRICS AND ELECTRICAL INSULATION | 2010年 / 17卷 / 06期

关键词：

Surface flashover in vacuum; Mo/Al2O3; cermet; triple junction; cofiring; secondary electron; FUNCTIONALLY GRADIENT MATERIALS; VOLTAGE-HOLDOFF PERFORMANCE; ALUMINA INSULATORS;

D O I：

10.1109/TDEI.2010.5658248

中图分类号：

TM [电工技术]; TN [电子技术、通信技术];

学科分类号：

0808 ; 0809 ;

摘要：

A new insulation structure of Mo/Al2O3 cermet-Al2O3 ceramic-Mo/Al2O3 cermet was designed to improve the surface flashover performance in vacuum through co-firing, where the volume addition of metal Mo was managed from 2 vol% to 50 vol% and there could exist one or two layers with different Mo addition in Mo/Al2O3 cermet. The influences of Mo addition of Mo/Al2O3 cermet on the surface flashover voltage in vacuum of samples were experimentally investigated, indicating that the surface flashover voltage of three and five-layer structures were improved by 77 % and 117 %, respectively. Through electrostatic field simulation, it was found that the improvement is caused by the weakening of the electric field at vacuum-insulator-cathode triple junction. On the basis of an in-depth investigation, it was also concluded that Mo particles of Mo/Al2O3 cermet layer can decline the surface charging and secondary electron emission near the triple junction. Then with a further increase of Mo addition, the decreasing trend of flashover voltage after the growing has been reasonably explained by investigating the configuration of Mo particles in Mo/Al2O3 cermet.

引用

页码：1931 / 1937

页数：7

共 23 条

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