阴极发射不足引发微波管高压击穿现象的研究

Study on High Voltage Breakdown Phenomenon Aroused by Less Cathode Emission in Microwave Tubes

关于阴极发射不足引发微波管高压击穿的机理一直缺乏相应的阐述。本文以一只高功率速调管为对象,记录了该管产生高压击穿时的阴极工作条件;计算了击穿点处阴极表面的静电场强度;找出了阴极边缘产生发射不足的原因;分析了发射不足对阴极发射点处电场分布的影响;论述了阴极边缘发射不足引发高压击穿的机理。研究表明,阴极边缘发射不足引起的发射点场增强效应、以及阴极边缘毛刺引起的场增强效应,共同作用使得微波管产生了高压击穿现象。

There has been little description on the mechanism of breakdown aroused by less cathode emission in microwave tubes. Focusing on a high-power klystron, the research includes measuring the cathode work conditions during tube breakdown; calculating the static electric field intensity at breakdown points on cathode surface; finding out the cause for less emission at cathode edge; analyzing the influence on the electric field distribution at the less emission points and discussing the mechanism of the high voltage breakdown caused by less emission at cathode edge. The study shows that both the field enhancement effects at emission points caused by less emission at cathode edge and that caused by cathode edge burrs lead to the high voltage breakdown in microwave tubes.