PCB基密封并联平面触发火花隙开关的设计及性能

Design and Performance of An Airtight Parallel Planar Triggered Spark⁃gap Switch Based on PCB Technology

为了提高爆炸箔起爆系统(exploding foil initiator system,EFIs)的作用可靠性,减小系统体积、降低系统成本,采用印制电路板(printed circuit board,PCB)工艺设计了一种密封并联平面触发火花隙开关(planar triggered spark-gap switch,PTS)。根据三电极的结构设计参数,采用PCB工艺批量制备了PTS,单只并联PCB-PTS的尺寸为13.5 mm(l)×7.5 mm(w)×2.5 mm(h)。基于显微计算机断层扫描重建了开关的立体和断面图像,结果显示PCB工艺满足开关的加工精度需求。开展了电极间隙的静电场分布仿真以解释开关的导通过程,并且据此计算了开关的理论自击穿电压(self-breakdown voltage,USB)。开关的电气性能测试表明:(1)并联PCB-PTS的USB略低于理论计算值,约为2000 V;(2)在大约50%~95%的USB范围内开关均能被可靠触发工作,并且电流上升时间稳定在约121.8 ns,峰值电流大于1500 A,满足EFIs的使用特性需求。最后,将该开关应用于爆炸箔起爆器(exploding foil initiator,EFI)进行发火实验,在0.22μF/1400 V的放电条件下,成功起爆了HNS-Ⅳ炸药。

It was designed that an airtight planar triggered spark‑gap switch(PTS)with parallel three‑electrode structure based on printed circuit board(PCB)technology,aiming to improve the working probability of exploding foil initiator systems(EFIs),as well as to reduce the size and cost of the system.The PTS was batched‑prepared with PCB technology according to the structural parameters of three electrodes,and the outline of a single parallel PCB‑PTS(P3)was 13.5 mm(l)×7.5 mm(w)×2.5 mm(h).The 3D and sectional appearances of the P3 were reconstructed via a micro computed tomography,which indicated that PCB technology could meet the machining precision.We simulated the electrostatic field distribution among the switch gap to explain the conduction process,and the theoretical self‑breakdown voltage(USB)was figured out based on the simulation results.Most im‑portantly,the test results of electrical performance of the switch show that(1)the about 2000 V USB derived from real‑world measurements was slightly lower than the calculated value;(2)P3 switched reliably at 50%-95%USB,and there was a constant risetime of about 121.8 ns and a peak current more than 1500 A,which fit the characteristic requirements of EFIs.Finally,P3 was applied to exploding foil initiator(EFI)to verify its practicability,and it was found that HNS‑IV pellets were reliably detonated under the ignition condition of 0.22μF/1400 V.