介绍了沿面击穿型触发真空开关的基本结构和工作过程。从沿面击穿型触发真空开关场致发射击穿机理的分析出发,通过数学建模,引入热力学运动方程,建立了沿面型触发真空开关的真空放电阴极斑点热传导模型,它可以用来描述和估算沿面放电方式下触发真空开关的时延特性。然后以初始等离子体的产生与扩展机理为重点,讨论了沿面型触发真空开关的时延特性,对于采用氢化钛作为涂敷材料的沿面击穿型触发真空开关,进行了具体的分析计算。研究表明,以所建立的阴极斑点热传导模型为基础计算得到的时延结果和Lafferty及Farrall的经典实验数据相吻合,证明了计算模型的正确性。
The basic structure and operating process of the surface-flashover triggered vacuum switch(TVS) were depicted. The field-breakdown mechanism in surface-flashover TVS was analyzed. Based on the behavior of heat in solids, the heat conduction model was set up for describing the heating process of the spots on the cathode, which occur in the the surface-flashover TVS when triggered. The model can be used for explaining the initial plasma's production and expansion mechanism and calculating the breakdown delay time on the improvement of the initial plasma produced by the trigger electrodes. For the surface-flashover TVS whose surface of dielectric between the trigger electrodes was coated with the Till layer, the calculation using the heat conduction model was carried out. The calculation results have a good agreement with Lafferty and Farrall's experimental data.