高压氢气亚纳秒开关击穿特性

Breakdown characteristic of high pressure hydrogen gas subnanosecond switch

在超宽谱脉冲产生辐射系统或脉冲功率源中,常用高压气体开关来产生快脉冲沿的高功率电磁脉冲。为了研究高压氢气亚纳秒开关的击穿特性,通过实验研究了氢气开关在高气压和短间隙距离条件下的击穿特性。开关输入脉冲的峰值幅度约220 kV,脉宽3～4 ns。氢气气压4～13 MPa,间隙距离0.4～1.2 mm。结果表明:开关击穿电压随气压升高而增加,且开关气压达到11 MPa后击穿电压随气压增加的趋势变缓;开关击穿电压随间距增加而增加,平均击穿场强随间距增加而减小,氢气开关平均击穿场强分布在3～7 MV/cm之间;开关导通时间随气压增加略有减小,随间隙距离增加有小幅增加。

Gas switches can be used to produce high power electromagnetic pulses with very fast risetime in UWB radiation systems.Due to its promising prospect in repetitive rate application,the experimental study on the high pressure hydrogen switch is conducted under pressure of 4 to 13 MPa and electrode gap spacing of 0.4 to 1.2 mm.The switch is pulse charged to more than 200 kV in less than 2 ns.Fast pulses with risetime less than 240 ps are obtained.The average breakdown electric field strength ranges from 3 to 7 MV/cm.The closure time of the hydrogen gaps decreases slightly with increasing the pressure or decreasing the gap space.