Abstract：The traditional methods for measuring internal pressure of vacuum tubes of breakers are the magnetron and power frequency voltage withstand test. A magnet coil is needed by magnetron and only very bad tubes can be detected by voltage withstand test. In this paper, a new method—inception field Eip of emission current method, is presented for measuring internal pressure P of vacuum tubes, by which magnetic coil isn’t need. Firstly vacuum gap 0.45mm is obtained by pulling the closed contacts, secondly power frequency voltage is applied on the gap and inherent gas adsorption layers are polished by electron bombardment or discharge current, finally the dynamic-balance gas adsorption layers are rebuilt again by ions capture and the Eip of gap is measured. It is known by theory analyses that the Eip is proportional to the P, so by detecting the value of Eip, the value of P can be obtained. The relationships between Eip and P is measured in laboratory, which is shown that the measuring ranges of P can be 100～10-3Pa by this new method.
赵子玉, 宋焕生, 江秀臣, 马乃祥, 罗利文, 王建伯, 刘崇方. 真空断路器真空度现场测量新技术[J]. 电工技术学报, 2009, 24(3): 99-103.
Zhao Ziyu, Song Huansheng, Jiang Xiuchen, Ma Naixiang, Luo Liwen, Liu Chongfang. New Technology for Measurement of Internal Pressure of Vacuum Breakers. Transactions of China Electrotechnical Society, 2009, 24(3): 99-103.
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