封闭式双间隙伪火花开关的触发及导通特性  

The Characteristics of Triggering and Conduction of a Sealed-off Double-gap Pseudospark Switch

作　　者：申赛康 闫家启 孙国祥 丁卫东[1] 曹关平 方春光 SHEN Saikang;YAN Jiaqi;SUN Guoxiang;DING Weidong;CAO Guanping;FANG Chunguang(State Key Laboratory of Electrical Insulation and Power Equipment,Xi’an Jiaotong University,Xi’an 710049,China;Jiangxi Jingguang Electronics Co.,Ltd.,Jingdezhen 333405,China)

机构地区：[1]西安交通大学电力设备与电气绝缘国家重点实验室,西安710049 [2]江西景光电子有限公司,景德镇333405

出　　处：《高电压技术》2021年第3期855-864,共10页High Voltage Engineering

基　　金：国家自然科学基金(51777163)。

摘　　要：伪火花开关是一种工作于巴申曲线左半支的低气压脉冲放电开关,具备耐受电压高、通流能力大、工作范围宽、寿命长、抖动低等优点,在脉冲功率装置中具有非常大的应用前景。为此研制了一款封闭式的双间隙伪火花开关,采用陶瓷–金属焊接密封方式,由改进型雪崩三极管纳秒脉冲电源和高介Ba TiO3陶瓷触发单元构成沿面放电式触发系统,触发稳定性极高。围绕伪火花开关的放电特性,主要研究了触发能量、阳极电压和工作气压对开关触发时延、抖动以及电压下降速率的影响规律。试验结果表明,触发系统极高的触发稳定性为伪火花开关触发时延抖动的降低提供了保障,最终可在间隙距离2.5mm的开关中将触发抖动降低至1ns以下;伪火花开关的电压下降速率受超密集辉光放电阶段发展过程的影响,而与空心阴极内部的过程无关,因此只受到阳极电压和工作气压的影响。此外,还分析了伪火花开关导通过程中电流过零点后发生淬灭的原因可能是开关阳极附近电子的产生速率低于消耗速率,使得反向放电通道的建立过程受阻,并采取了相应措施进行改善。Pseudospark switch is a kind of low-pressure pulse discharge switch operating on the left half branch of Paschen curve. It has the advantages of high withstand voltage, large current capacity, wide working range, long life, small jitter, etc. Therefore, it has a very large application prospect in pulse power devices. In this paper, a sealed-off double-gap pseudospark switch was developed. The ceramic-metal welding seal was adopted. A surface discharge trigger system consisting of a modified nanosecond pulse generator based on avalanche transistors and a trigger unit based on Ba TiO3 with high dielectric constant has extremely high stability. Moreover, the discharge characteristics of pseudospark switch was studied. The effects of trigger energy, anode voltage, and the filament current on the trigger delay, jitter, and the rate of voltage drop were studied. The results show that the high stability of trigger system can guarantee the low jitter of trigger delay, and the jitter can be reduced to less than 1 ns in the pseudospark switch with a clearance distance of 2.5 mm. The drop rate of anode voltage is influenced by the development process of superdense glow discharge, and is independent of the process that occurs inside the hollow cathode. Therefore, it is determined by anode voltage and operating pressure. In addition, the reasons why current is quenched in the process of pseudospark conduction are analyzed, and may be the production rate of electrons is lower than consumption rate, thus the process of forming discharge channel reversely is blocked. And some measures are taken to alleviate it.

关 键 词：伪火花开关 触发时延 抖动 电压下降速率 电流淬灭 

分 类 号：TM564[电气工程—电器]