15 MA Z箍缩装置真空磁绝缘传输线损失电流的电路模拟  

Circuit simulation of current loss in magnetically insulated transmission line system in 15-MA Z-pinch driver

作　　者：龚振洲 魏浩[2] 范思源 孙凤举[2] 吴撼宇[2] 邱爱慈[1,2] Gong Zhen-Zhou;Wei Hao;Fan Si-Yuan;Sun Feng-Ju;Wu Han-Yu;Qiu Ai-Ci(State Key Laboratory of Electrical Insulation and Power Equipment,Institute of Electrical and Engineering,Xi’an Jiaotong University,Xi’an 710049,China;State Key Laboratory of Intense Pulsed Radiation Simulation and Effect,Northwest Institute of Nuclear Technology,Xi’an 710024,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]西北核技术研究所,强脉冲辐射环境模拟与效应国家重点实验室,西安710024

出　　处：《物理学报》2022年第10期225-233,共9页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:51790524,11975186)资助的课题。

摘　　要：采用TL-code电路编码方法,建立了15 MA Z箍缩装置多层圆盘锥磁绝缘传输线的全电路模型,分析了外磁绝缘传输线、汇流柱和内磁绝缘传输线三个区域电流损失特性.外磁绝缘传输线磁绝缘形成过程的空间电荷损失持续时间约30 ns,对负载电流影响小.进入磁绝缘稳态时,外磁绝缘传输线末端鞘层电子流损失约300 k A.汇流柱区域电流损失与电极等离子体运动速率密切相关,当等离子体运动速率为21 cm/μs时,负载峰值电流时刻损失电流约4 MA.内磁绝缘传输线电流损失取决于阳极离子流种类,电流损失在负载峰值电流时刻之后,损失电流约2.1 MA.当15 MA装置驱动长度2 cm、半径2 cm、质量3 mg丝阵负载时,绝缘堆峰值电流约18 MA,负载峰值电流约13.5 MA、峰值时间(0—100%)约为100 ns.In this paper,a transmission line circuit model of a magnetically insulated transmission line(MITL) system is developed for a 15-MA Z-pinch driver.The current loss characteristics of multi-level MITL and the ion emission due to the expansion of anode and cathode plasma in the post hole vacuum convolute(PHC) and innerMITL region are analyzed.The spatiotemporal distribution of current loss of the outer-MITL and ion current of the PHC and inner-MITL of the 15 MA driver are obtained.The results show that the first electron emission happens at the end of constant-impedance MITL and the beginning of constant-gap MITL,and the end of constant-gap MITL firstly achieves fully magnetic insulation.Electron emission occurs at the start of load current and its duration is about 30 ns,which is short for a single pulse and has little effect on the rising edge nor peak value of the load current.The waveform of the electron flow varying with time resembles a saddle shape,whose amplitude first goes up,then comes down,and increases again.The electron flow current decreases from upstream to downstream in constant-gap MITL in space.The starting time of the loss current of the PHC is synchronized with the gap closing time.The loss current amplitude increases rapidly,reaching 4 MA at the peak load current time and 6.5 MA in the end.In the inner-MITL region,the main positive ion species are protons and oxygen 2+.At the beginning,the ion loss current of protons is larger than that of oxygen 2+,and then the protons are quickly magnetically insulated due to the small charge-to-mass ratio.The ion loss current of the inner-MITL region mainly increases after the peak load current time,and its peak value is 2.1 MA.Given the input conditions,the stack is going to deliver current of about 18 MA,the hold voltage is about 2.3 MV,and the peak load current is about 13.5 MA.

关 键 词：磁绝缘传输线 传输线编码 鞘层电子流 离子流 

分 类 号：TM75[电气工程—电力系统及自动化]