宽工作系数大容量四电极紫外预电离气体开关

Four-electrode UV Pre-ionization Gas Switch with Wide Operating Coefficient and Large Capacity

针对兆安级放电电流、微秒级放电脉宽脉冲功率装置对气体开关的需求,设计了四电极紫外预电离气体开关,对其结构进行优化并开展研究。试验结果表明:紫外预电离和高幅值触发电压是实现开关宽工作系数短时延、低抖动的决定性因素。在峰值为140 kV、前沿<30 ns(10%~90%峰值电压时间)的触发电压、工作系数(开关工作电压与自击穿电压的百分比)在40%~70%范围时,实现了2台预电离气体开关的同步导通。不同工作系数之间,开关导通时延分散性(极差)<20 ns。开关具备峰值电流≥230 kA,通流能力≥18 C/次、150次试验后开关自击穿电压降低<2%,触发特性无明显劣化。所设计的气体开关解决了开关大容量以及宽工作系数短时延、低抖动的难题,满足工程应用需求,对于进一步实现并联大容量气体开关的同步导通具有重要意义。

To meet the requirements of a pulse power device with MA-level microsecond discharge current,a four-electrode UV pre-ionization gas switch was designed and its structure was optimized,and the relative research was carried out.The experiments show that UV pre-ionization and high-amplitude trigger voltage are important factors to realize short delay and low jitter under the wide operating coefficient of the switch.With a trigger voltage of 140 kV,rise time less than 30 ns(the 10%~90%peak voltage time),the synchronous conduction of two pre-ionization gas switches is realized under the condition of 40%~70%operating coefficient(percentage of the switch operating voltage divided by self-breakdown voltage).Between different operating coefficients,the dispersion(extreme difference)of the delay time is less than 20 ns.The switch has a current flow capacity of no less than 230 k A and 18 C/shot,after 150 times of large-current experiments,the switch self-breakdown voltage changes less than 2%,and the triggering characteristics are not significantly deteriorated.The switch designed in this paper solves the problem of short-time delay and low jitter under the condition of large capacity and a wide operating coefficient,and meets the needs of engineering applications.It is of great significance to further realize the synchronous conduction of parallel operating large-capacity gas switches.