水平极化EMP模拟器参考场位置的选取

水平极化EMP模拟器是开展大型系统电磁脉冲效应试验的典型装置,参考场是效应试验中最重要的测量参数.分析了地面和受试对象对辐射波电场环境的影响,对水平极化EMP模拟器参考场位置的选取给出建议.     

基于TEM喇叭的辐射波模拟器天线辐射性能研究

研究了基于TEM喇叭天线的辐射波模拟器天线性能,分析了天线性能参数如结构角、天线长度、宽高比等对天线辐射性能的影响。为了提高天线低频辐射能力,提出了2种增加天线有效长度的方法,结果表明两种方法均在一定程度上对辐射场波形有所改善。在天线长度的选择符合工程实际的条件下,通过选择合适的宽高比和增加天线有效长度的方法取得了较好的场波形。     

可移动系统场内线缆早期高空电磁脉冲耦合响应分析

本文利用传输线方程,计算了200 m长可移动系统场内线缆的早期高空电磁脉冲(HEMP)感应电流,并对感应电流的波形特征进行了分析,结果表明:在国家军用标准GJB 1389A—2005规定的电磁脉冲(EMP)环境中,可移动系统场内线缆采用美国军用标准MIL-STD-188-125-2规定的早期HEMP防护指标具有合理性。     

EAST装置ICRF天线电特性分析与优化研究

射频波加热是磁约束核聚变装置的重要加热方式.本论文基于 EAST 装置离子回旋共振(ICRF)加热天线结构和运行参数,运用高频分析方法对 ICRF天线开展电特性分析模拟,获得 ICRF天线射频电势和电场分布特性,初步评估了天线电特性.基于天线电场分布特性和分析结果,从天线结构和运行相位两方面对 ICRF天线电特性进行了...     

S波段波导窗的设计

采用高频结构模拟器(HFSS)建立波导窗物理模型,并计算波导窗内的电场分布、大小和方向,以及波导窗的射频参数如频率与带宽、输入电压驻波比,从而为改进波导窗提供了理论依据,并最终设计了一个适合5 MW、45 kW高功率传输的波导窗.     

双端匹配电路的电容分压器PSPICE分析及应用

详细介绍了具有双端匹配电路电容分压器的基本原理,给出了一种双端匹配电路电容分压器的电路参数,通过PSPICE软件模拟了该分压器的工作过程,并介绍了该电容分压器在TEM小室和有界波电磁脉冲模拟器在监测电场方面的应用.     

脉冲电场传感器灵敏度响应系数一致性的实验研究

电场传感器灵敏度的校准是电磁场测量中的重要环节.本文运用任意波形发生器(AWG),在TEM小室中激励不同形式的脉冲电场,对自行研制的偶极天线测量系统的灵敏度进行了校准实验.结果表明,在传感器的频带范围内,不同脉冲波形的灵敏度曲线基本一致,由实验室校准系统给出的灵敏度参数适用于频带范围内的未知波形脉冲电场的测量.     

电磁脉冲辐射场试验中的光纤传输测量系统

辐射波电磁脉冲模拟器是进行大型电子系统电磁脉冲效应试验研究的重要设备。针对辐射波电磁脉冲模拟器试验的特点及其对测量系统的要求,介绍了基于光纤传输的电磁脉冲测量系统的构成,测量系统的分类及测量系统的标定方法。并对电磁脉冲测量系统的不确定度评定方法进行了讨论。通过辐射场试验,给出了测量系统的应用实例及对测量结果的分析。     

50kV,1ns前沿高压脉冲源的研制

介绍了50kV,1ns前沿高压脉冲源的工作原理及设计部件的研制,给出了脉冲高压源的输出波形,该高压脉冲源与有界波电磁脉冲模拟器辐照天线相接,可在其工作空间内产生前沿为1．2ns,脉宽为50ns的电磁环境,用于电子系统的电磁脉冲效应研究。     

“春雷号”有界波EMP模拟器暂态过程的计算

对“春雷号”有界波ＥＭＰ模拟器主开关动作前后的暂态过程建立了相应的等效电路及微分方程，用定步长龙格－库塔法进行了数值求解，并与实测波形进行了比较，提出了改善输出波形的几种方法。这对于模拟器的设计、调整及改进都有一定的意义。     

高功率脉冲源双锥负载不同端接状态的辐射特性分析

高功率脉冲源的双锥负载,在调试过程中将辐射强电磁波,对周围电子设备造成严重干扰。论文采用时域有限差分(FDTD)法,对双锥天线的近场辐射过程进行模拟计算,考察双锥终端分别为开路、短路和连接电阻负载三种状态下的电磁辐射特性,证明用电阻线连接双锥终端,可以同时抑制终端反射和空间辐射,保护脉冲源自身和电子设备。最后给出实验室内关键位置处的电磁骚扰水平。     

HEMP线缆效应研究中的几个关键因素

线缆耦合是HEMP对电子系统作用的主要途径之一。传输线模型是分析场线耦合常用的研究方法。针对影响线缆中电压、电流响应的几个关键因素,如地面附近的电磁环境、所采用的传输线分析模型、地面土壤电导率以及线缆架高等,计算了线缆的响应,并从机理上给出了解释。所得到的分析结论对于实验研究及防护设计都有参考意义。     

Temporal electric field of a helium plasma jet by electric field induced second harmonic (E-FISH) method

Electric field is an important parameter of plasma,which is related to electron temperature,electron density,excited species density,and so on.In this work,the electric field of an atmospheric pressure plasma jet is diagnosed by the electric field induced second harmonic(E-FISH) method,and the time-resolved electric field under different conditions is investigated.When positive pulse voltage is applied,the electric field has a peak of about 25 kV cm^-1 at the rising edge of the voltage...     

An Investigation of Ionic Flows in a Sphere-Plate Electrode Gap

This paper presents analyses of ion flow characteristics and ion discharge pulses in a sphere-ground plate electrode system.As a result of variation in electric field intensity in the electrode gap,the ion flows towards electrodes generate non-uniform discharging pulses.Inspection of these pulses provides useful information on ionic stream kinetics,the effective thickness of ion cover around electrodes,and the timing of ion clouds discharge pulse sequences.A finite difference time domain(FDTD)based space-charge motion simulation is used for the numerical analysis of the spatio-temporal development of ionic flows following the first Townsend avalanche,and the simulation results demonstrate expansion of the positive ion flow and compression of the negative ion flow,which results in non-uniform discharge pulse characteristics.     

Choice of basic parameters for high-energy linear electron accelerators

The choice of basic operating parameters for high-energy linear electron accelerators is analyzed. The length of the accelerator, the number of sections, the required power supply, and the cost of construction and operation are considered as functions of the electric field strength along the axis of the waveguide, the sections of which are supplied independently by radiofrequency sources. The minimum costs of accelerator construction and operation are independent of the final electron energy. It is shown that it is most desirable to use radio-frequency sources of highest possible power (greater than 20 megawatts) for supplying the accelerator section. Consideration is given to the problem of increasing the length of the useful part of the radiofrequency pulse.Reported at the All-Union Conference on High-Energy Particle Physics, 1956.     

地面放射性异常引起电离层扰动的计算研究

地面的放射性主要来源于空间辐射、地壳放射性元素衰变和人工核活动等,地面放射性可引起地表电场的变化,地表电场变化的区域和强度达到一定的条件后可引起电离层的扰动。基于LAIC电场机制假设,本文从地面放射性引起空气电离开始推导地表大气电导率变化、地面垂直电场至电离层底部传导过程,根据临界电场理论计算地面大气垂直电场、大气附加电流密度以及电离层准静态电场的电势分布,最后通过格林函数法求解得到电离层中水平电场的分布。建立了基于地面放射性活度的地表大气电导率公式,改进了地表异常电场传播到电离层的计算过程,给出了电离层电场扰动的计算公式。利用氡和地面电场仪的实例观测数据对地面放射性异常引起的电离层扰动的计算过程进行了验证,理论计算得到的地面电场和电离层扰动的结果与实际测量结果基本一致。     

Multiple current peaks and spatial characteristics of atmospheric helium dielectric barrier discharges with repetitive unipolar narrow pulse excitation

Atmospheric dielectric barrier discharges driven by repetitive unipolar narrow pulse excitation are investigated numerically by using one-dimensional fluid models.The one-dimensional simulation focuses on the effects of applied voltage amplitude,pulse repetition frequency,gap width and γ coefficient on the multiple-current-pulse (MCP) discharge.The results indicate that the MCP behavior will lead to the stratification of electron density distribution in axial direction.Traditional MCP manipulating methods,such as reducing the applied voltage amplitude,increasing the applied voltage frequency,adjusting the gap width,cannot regulate MCPs exhibiting in this work.Further analyses reveal that the increasing electric field of the cathode fall region is the basis for the emergence of MCP behavior.     

同步发电机励磁系统实测校核数据库的设计

励磁系统参数对电网稳定性影响较大,为了满足对现场实测报告的自动校核需求,现需要一种励磁系统模型数据库对大量的励磁系统参数进行录入储存和计算。针对目前励磁系统参数的重要性,以及励磁系统更新换代快的现状,开发出一套具有3种现场实测数据录入方式的励磁系统模型数据库,实现了励磁系统模型及其参数的录入、储存及校核自动输出,提高了工作效率,能够为电力系统稳定分析计算提供更完善的数据基础。     

Kinetic study of key species and reactions of atmospheric pressure pulsed corona discharge in humid air

In this study, we examined the key particles and chemical reactions that substantially influence plasma characteristics. In summarizing the chemical reaction model for the discharge process of N2–O2–H2O(g) mixed gases, 65 particle types and 673 chemical reactions were investigated. On this basis, a global model of atmospheric pressure humid air discharge plasma was developed, with a focus on the variation of charged particles densities and chemical reaction rates with time under the excitation of a 0–200 Td pulsed electric field. Particles with a density greater than 1% of the electron density were classified as key particles. For such particles, the top ranking generation or consumption reactions (i.e. where the sum of their rates was greater than 95% of the total rate of the generation or consumption reactions) were classified as key chemical reactions. On the basis of the key particles and reactions identified, a simplified global model was derived. A comparison of the global model with the simplified global model in terms of the model parameters, particle densities, reaction rates (with time), and calculation efficiencies demonstrated that both models can adequately identify the key particles and chemical reactions reflecting the chemical process of atmospheric pressure discharge plasma in humid air. Thus, by analyzing the key particles and chemical reaction pathways, the charge and substance transfer mechanism of atmospheric pressure pulse discharge plasma in humid air was revealed, and the mechanism underlying water vapor molecules' influence on atmospheric pressure air discharge was elucidated.