Improvement of Surface Flashover Performance of Al2O3 Ceramics in Vacuum by Adopting A-B-A Insulation System

被引：12

作者：

Li Shengtao ^{[1
]}

Zhang Tuo ^{[1
]}

Huang Qifeng ^{[1
]}

Li Weiwei ^{[1
]}

Ni Fengyan ^{[1
]}

Li Jianying ^{[1
]}

机构：

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

来源：

PLASMA SCIENCE & TECHNOLOGY | 2011年 / 13卷 / 02期

关键词：

surface flashover in vacuum; A-B-A insulator; triple junction; electric field distribution; cermet; EMISSION;

D O I：

10.1088/1009-0630/13/2/21

中图分类号：

O35 [流体力学]; O53 [等离子体物理学];

学科分类号：

070204 ; 080103 ; 080704 ;

摘要：

A new insulation system with inorganic A-B-A insulators was proposed to improve the surface flashover performance in vacuum. Inorganic A-B-A insulator samples of Mo/Al2O3 cermet-Al2O3 ceramic-Mo/Al2O3 cermet were prepared, in which the conductivity and permittivity of the Mo/Al2O3 cermets were controlled through different amount of metallic molybdenum powder added. The effects of both conductivity and permittivity of Mo/Al2O3 cermets on the DC and impulse surface flashover voltage in vacuum were experimentally investigated. The result showed that the DC and impulse surface flashover voltage were improved by 52% and 95%, respectively. For the distribution of electric field, two triple junctions, i.e., vacuum-layer A-cathode (TJ1) and vacuum-layer A-layer B (TJ2) were prepared with the introduction of layer A into the A-B-A insulation system. Based on the electric field distribution obtained via electrostatic field simulation and Maxwell-Wagner three-layer model, the electric field of TJ1 decreases while that of TJ2 increases with the increase in conductivity and permittivity of layer A under applied DC and impulse voltage, respectively. Therefore, the improvement of surface flashover performance of A-B-A insulators has been reasonably explained.

引用

页码：235 / 241

页数：7

共 16 条

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