电容快放电型触发器的电路分析与设计

为获得快前沿的高电压脉冲,分析了电容放电型触发器的电路,利用简化的等效电路研究了放电回路参数和气体开关的火花通道电阻、电感对触发脉冲上升时间的影响.分析了电压波在高阻抗负载上形成触发脉冲的过程,讨论了不同置地元件对输出波形的影响.在此基础上,给出了快前沿的电容放电型触发器的基本设计原则,并完成了30与100 kV快前沿...     

Modeling Methods for the Main Switch of High Pulsed-Power Facilities Based on Transmission Line Code

Based on the transmission line code （TLCODE）, a circuit model is developed here for analyses of main switches in the high pulsed-power facilities. With the structure of the ZR main switch as an example, a circuit model topology of the switch is proposed, and in particular, calculation methods of the dynamic inductance and resistance of the switching arc are described. Moreover, a set of closed equations used for calculations of various node voltages are theoretically derived and numericMly discretized. Based on these discrete equations and the Matlab program, a simulation procedure is established for analyses of the ZR main switch. Voltages and currents at different key points are obtained, and comparisons are made with those of a PSpice L-C model. The comparison results show that these two models are perfectly in accord with each other with discrepancy less than 0.1%, which verifies the effectiveness of the TLCODE model to a certain extent.     

多级多通道低电感火花气体开关

简述了几种多级多通道低电感火花气体开关 ,分析了该类气体开关的设计原则 ,提出了一种中间电极采用不锈钢弹簧、触发电极位于主放电通道之外的同轴状气体开关的设计思想 ,初步试验表明 ,设计可行 ,开关电感较小。     

Ultra Fast Shutter Driven by Pulsed High Current

Radiation simulation utilizing plasma radiation sources (PRS) generates a large number of undesirable debris, which may damage the expensive diagnosing detectors. An ultra fast shutter (UFS) driven by pulsed high current can erect a physical barrier to the slowly moving debris after allowing the passage of X-ray photons. The UFS consists of a pair of thin metal foils twisting the parallel axes in a Nylon cassette, compressed with an outer magnetic field, generated from a fast capacitor bank, discharging into a single turn loop. A typical capacitor bank is of 7.5 μF charging voltages varying from 30 kV to 45 kV, with corresponding currents of approximately 90kA to140 kA and discharging current periods of approximately 13.1 μs. A shutter closing time as fast as 38 microseconds has been obtained with an aluminium foil thickness of 100 micrometers and a cross-sectional area of 15 mm by 20 mm. The design, construction and the expressions of the valve-closing time of the UFS are presented along with the measured results of valve-closing velocities.     

DG4型0.08mm薄带硅钢磁芯的脉冲磁化特性

本文对高功率直线脉冲变压器常用的一种0.08mm薄带DG4型硅钢片绕制的环形磁芯的脉冲磁化特性进行了实验研究。结果表明，在周期为百微抄量级欠阻尼振荡激磁电流作用下，磁芯磁滞回线基本上与工频电流激磁时相同，而周期在微秒量级欠阻尼振荡激磁电流作用下，磁芯在激磁电流第一个脉冲磁化达到饮和后，当激磁电流反向时，磁芯不能随之反向磁化，而是一直处于饱和状态，失去磁性。     

Numerical Simulation of Azimuthal Uniformity of Injection Currents in Single-Point-Feed Induction Voltage Adders

In order to investigate the injection current uniformity around the induction cell bores,two fully electromagnetic(EM) models are respectively established for a single-stage induction cell and an induction voltage adder(IVA) with three cells stacked in series,without considering electron emission.By means of these two models,some factors affecting the injection current uniformity are simulated and analyzed,such as the impedances of adders and loads,cell locations,and feed timing of parallel driving pulses.Simulation results indicate that higher impedances of adder and loads are slightly beneficial to improve injection current uniformity.As the impedances of adder and loads increase from 5 Ω to 30 Ω,the asymmetric coefficient of feed currents decreases from 10.3%to 6.6%.The current non-uniformity within the first cell is a little worse than that in other downstream cells.Simulation results also show that the feed timing would greatly affect current waveforms,and consequently cause some distortion in pulse fronts of cell output voltages.For a given driving pulse with duration time of 70-80 ns,the feed timing with a time deviation of less than 20 ns is acceptable for the three-cell IVAs,just causing the rise time of output voltages to increase about 5 ns at most and making the peak voltage decrease by 3.5%.     

Experimental investigation on the development characteristics of initial electrons in a gas pressurized closing switch under DC voltage

As one of the most important elements in linear transformer driver(LTD) based systems, the gas pressurized closing switches are required to operate with a very low prefire probability during the DC-charging process to ensure reliable operation and stable output of the whole pulsed power system. The most direct and effective way to control the prefire probability is to select a suitable working coefficient. The study of the development characteristics of the initially generated electrons is useful for optimizing the working coefficient and improving the prefire characteristic of the switches. In this paper an ultraviolet pulsed laser is used to generate initial electrons inside the gap volume. A current measuring system is used to measure the time-dependent current generated by the growth of the initial electrons so as to study the development characteristics of the electrons under different working coefficients. Experimental results show that the development characteristics of the initial electrons are influenced obviously by the working coefficient. With the increase of the working coefficient, the development degree of the electrons increases consequently. At the same times, there is a threshold of working coefficient which produces the effect of ionization on electrons. The range of the threshold has a slow growth but remains close to 65% with the gas pressure increase. When the working coefficient increases further, γ processes are starting to be generated inside the gap volume. In addition, an optimal working coefficient beneficial for improving the prefire characteristic is indicated and further tested.     

基于IBIS模型的多路脉冲信号源ADS仿真

使用高速比较器+两级时钟扇出buffer+比较器输出CMOS电平方案,利用ADS的Integrity–IBIS模块,搭建了80台示波器用脉冲信号源。介绍了IBIS模型原理、语法结构及模型适用性,并进行了瞬态仿真,分析了高速比较器IC、时钟扇出IC和脉冲输出IC之间的差分信号完整性,对最终输出信号的延迟和抖动进行了计算。仿真结果表明：使用高速比较器+两级时钟扇出buffer+比较器输出CMOS电平方案可获得80路同步触发信号;输入输出信号延迟<2.6ns,抖动<11ps,50Ω负载时输出信号幅值1.97V,前沿997ps,满足多路示波器外触发信号要求。     

Comparative study on breakdown characteristics of trigger gap and overvoltage gap in a gas pressurized closing switch

Gas pressurized closing switches are one of the most important elements in FLTD-based systems. Improving the trigger performance of gas switches is useful for optimizing the output parameters and the reliability of the FLTD. In this paper, the breakdown characteristics of the trigger gap and the overvoltage gap are studied experimentally. The reasons for the different breakdown performance of the two gaps are also investigated. The results show that the breakdown delay of the trigger gap is more influenced by the trigger voltage, while the breakdown delay of the overvoltage gap is more influenced by the working coefficient and always higher than that of the trigger gap. The jitter of the trigger gap is more influenced by the trigger voltage and accounts more than 60% of the total switch jitter, while the jitter of the overvoltage gap is hardly changed with the trigger voltage as well as the working coefficient and maintains less than 1.4 ns. It is proved that the discharging product from the trigger gap can effectively reduce the breakdown delay and jitter of the overvoltage gap. Based on that, the effect and improvement of pre-ionization on the two gaps are also studied. It is concluded that the jitter of the trigger gap reduces obviously when the pre-ionization is added, while the pre-ionization almost has no effect on the jitter of the overvoltage gap. The jitter of the overvoltage gap is about two times higher than the trigger gap in the pre-ionizing switch.     

Experimental Study of the Multi-gap Multi-channel Gas Spark Closing Switch

1. IntroductionHigh-voltage and high--current closing switch is oneof the key elements in pulsed-power systems. It hasextensive applications in generating high--voltage andhigh-current pulses With the recent development ofpulsed-X-r8y simulator and high--power Z--pinch tech-nology [l,2], it is required that the closing switch is ofsmall inductance, low jitter, high conducting currentand long operating life.One of the methods for the reduction of switchlnductance, jitter and electrode erosion …