预电离开关触发间隙击穿时延特性  

Breakdown Time Delay Property of Trigger Gap in Pre-ionization Gas Switch

作　　者：王天驰 陈伟 杜应超[1,3] 王海洋 郭帆 谢霖燊 WANG Tianchi;CHEN Wei;DU Yingchao;WANG Haiyang;GUO Fan;XIE Linshen(Department of Engineering Physics,Tsinghua University,Beijing 100084,China;State Key Laboratory of Intense Pulsed Radiation Simulation and Effect,Northwest Institute of Nuclear Technology,xi'an 710024,China;Key Laboratory of Particle&Radiation Imaging,Tsinghua University,Ministry of Education,Beijing 100084,China)

机构地区：[1]清华大学工程物理系,北京100084 [2]西北核技术研究院强脉冲辐射环境模拟与效应国家重点实验室,西安710024 [3]清华大学粒子技术与辐射成像教育部重点实验室,北京100084

出　　处：《高电压技术》2020年第6期1994-2003,共10页High Voltage Engineering

摘　　要：为了研究预电离开关触发间隙在是否叠加主间隙电场时的击穿时延特性,采用基于气体放电流体模型和有限容积法的二维程序对氮气中气压0.1~0.7MPa、电极间距0.5mm和1mm、间隙上脉冲电压上升速率与气压的比值d(u/p)/dt等于0.8 kV/(ns·MPa)和0.4 kV/(ns·MPa)、主间隙与触发间隙之间分压比不同时叠加主间隙径向电场下触发间隙的击穿过程进行模拟并对比实验数据。结果表明,由于d(u/p)/dt影响间隙中的平均归一化电场Eav/p的变化过程,d(Eav/p)/dt值确定时,气压、初始电子产生的时刻和电极间距等是影响间隙击穿时延的主要因素。叠加主间隙径向电场会增强触发间隙中的空间电场并加快电子崩的发展过程,但也会使电子沿径向漂移,导致击穿时延增长。为削弱叠加径向电场的影响,可以减小分压比、增大d(u/p)/dt和阳极直径。To investigate the breakdown time delay characteristic of the trigger gap in a pre-ionization gas switch in the presence and absence of superposed transverse electric field produced by main gap,using a 2 D code based on fluid model and finite volume method,we simulated the breakdown process of 0.5 mm and 1 mm trigger gap in N2 under gas pressure from 0.1 MPa to 0.7 MPa,the rising rate of input voltage divided by gas pressure d(u/p)/dt=0.8 k V/(ns·MPa)and 0.4 kV/(ns·MPa),in the presence and absence of superposed transverse electric field when the voltage division ratio between main gap and trigger gap varied.Meanwhile,we compared the results with experimental data.The results indicate that because d(u/p)/dt influences the changing process of Eav/p,which is the normalized average electric field in the trigger gap,gas pressure,gap distance and the time when initial electrons emerge are main factors of breakdown time delay when d(Eav/p)/dt is fixed.Superposed transverse electric field will enhance the electric field in the trigger gap and accelerate the development of electron avalanche,but it can also lead to the transverse drifting of electrons,which increases the breakdown time delay.Reducing the voltage division ratio and increasing d(u/p)/dt and the diameter of the anode can weaken the influence of transverse electric field.

关 键 词：预电离开关 触发间隙 击穿时延 流体模型 有限容积法 

分 类 号：TM564[电气工程—电器]