【摘要】 真空灭弧室真空度的传统测试方法主要有磁控放电法及工频耐压法。磁控放电法需要使用磁场线圈,而工频耐压法只能检出严重漏气的灭弧室。该文使用微放电起始电压Ud与发射电流起始电压Ue之比Ud/Ue测量灭弧室的真空度。该方法不需要施加磁场,而是使用下述方法进行测量:将闭合的灭弧室触头强行拉开0.2～0.3mm,然后在触头间隙上施加工频高电压,利用间隙微放电电流对触头表面进行老练,以除去触头表面原有的吸附层,最后再测量间隙的微放电起始电压Ud与发射电流起始电压Ue。理论研究表明,真空灭弧室内的真空压强p越小,Ud/Ue越大,故通过测量Ud/Ue的大小,就可以获得真空灭弧室内的真空度。文中在实验室的真空比对系统上对不同管型灭弧室的Ud、Ue、Ud/Ue与真空压强p的关系进行了测试,测试结果表明,该文提出的Ud/Ue法,其真空度测量范围能达到100～10-3Pa。更多还原

【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 picked out by voltage withstand test.A new method——the ratio of inception voltage Ud of micro-discharge to inception voltage Ue of emission current can be used to measure internal pressure p of vacuum tubes.By this method,internal pressure of vacuum tubes can be measured without using magnetic coil,but with following process:firstly,vacuum gap 0.2～0.3 mm is obtained by forced pulling the closed contacts,secondly,power frequency voltage is applied to the gap and inherent gas adsorption layers are polished by micro-discharge current,finally,the Ud and Ue of the vacuum gap is measured.Theoretical study shows that the bigger Ud/Ue is,the smaller p is.So by measuring the value of Ud/Ue,the value of p can be obtained.The relationships of Ud,Ue,Ud/Ue with p are measured in laboratory,the test results show that the measuring ranges of p can be 100～10-3 Pa by this new method.更多还原