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为研究强电磁脉冲辐照下无人机内部三绞线的终端响应特性,本文基于传输线理论提出了三绞线在强电磁脉冲辐照下终端响应的建模方法.首先确定了三绞线三螺旋物理结构,给出绞线束在笛卡尔坐标系下的参数方程,建立了具有均匀扭曲特征的三绞线模型;然后推导了电磁脉冲辐照下三绞线终端电流的频域方程,采用快速傅里叶逆变换得到时域解,并与CST仿真结果进行对比,验证了算法的准确性;最后分析了三绞线终端电流随线缆长度,线缆螺距,电磁场极化角、方位角、俯仰角的耦合响应规律.结果表明:三绞线终端感应电流随线缆长度和螺距的增加而增大;入射波的俯仰角和方位角在[0, 90°]时,感应电流随入射角度的增加呈现出先增大后降低的规律.研究结果对提高无人机电磁防护能力具有重要意义. 相似文献
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地闪电磁脉冲对近地电缆外导体的耦合研究 总被引:1,自引:0,他引:1
采用时域有限差分法计算得出地闪回击电流近场在地面附近的分布,将场值代入离散化后的传输线方程后,计算了近地电缆外导体上的感应电流,分析了大地电参数、导线架高、长度以及与雷击通道距离等因素对感应电流的影响.计算结果显示,距雷击通道200m以内的近场对敏感设备及系统构成的威胁最为严重,应作为地闪电磁脉冲环境预测研究的重点. 相似文献
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对全系统进行了抗电磁脉冲分析,分别阐述了系统各耦合环节辐照试验技术和全系统考核验证试验技术。针对高空核爆产生的高空电磁脉冲对地面电子学系统产生的耦合效应情况,分析在系统内部和外部产生感应电流和感应电压的过程;在不同的屏蔽条件下,全系统不同部分将面临不同的耦合效应,采用不同的实验测试方法。重点分析了高空电磁脉冲对电子学系统的作用,在系统内部和外部产生感应电流和感应电压的过程;阐述了不同模拟试验对应的具体对象,并对不同模拟试验方法进行了介绍。 相似文献
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《Electron Device Letters, IEEE》1980,1(5):69-71
Two and three terminal planar InP TED structures have been fabricated using semi-insulating iron doped InP substrates grown by the liquid encapsulated Czrochalski technique. Two terminal TEDs employed a vapor phase epitaxial n layer grown directly on the substrate. Direct implantation of29Si into the substrate to form an extended n type layer was used for three terminal TEDs. Both types of TEDs displayed negative resistance regions in the pulsed I/V characteristics with current dropbacks of between 25% and 35%. The highest observed pulse power output for two terminal TEDs was 1.25 mW at 11.7 GHz. Three terminal TEDs delivered their best pulsed performance at 2.1 GHz with 106 mW and 6% efficiency. 相似文献
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本文介绍了"多路强电(磁)脉冲发生装置"同步精度研究采用的每路输出"储能电容+同轴脉冲大电流火花开关放电"型高压脉冲形成电路。用同轴电缆作为传输线将工作部件连接起来,以脉冲气体激光器作为终端负载(或其他负载,如磁脉冲线圈、电水锤等)组成多路相互隔离的强电脉冲充放电路,设计采用"多路高压纳秒脉冲发生器装置"进行同步精度触发,使高功率气体激光器的放电系统同时获得多路同步输出的高强电脉冲能量进行激励放电。同步精度装置的实验研究结果表明,多路同步导通强电脉冲能量已超出100kJ级,多路触发脉冲同步精度〈10ns,可为脉冲气体激光器提供更加超强激励触发能量获得高功率激光。 相似文献
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借助于TACD数值仿真,对具有交叉指状结构的锗硅异质结双极型晶体管(SiGeHBT)中由重离子辐射诱导的单粒子瞬态(SET)效应展开了详细的研究.首先分析了重离子辐射诱导的电势和场强的变化,阐明了SiGe HBT中单粒子瞬态机制.然后,通过对比重离子入射至器件不同位置时各电极的瞬态电流和感生电荷的收集情况,确定了集电极/衬底(CS)结及附近区域为SiGe HBT单粒子瞬态的敏感区域.结果表明相对于集电极和衬底的电荷收集,基极和发射极收集的电荷可忽略不计.此外,各电极的瞬态电流和电荷收集还具有明显的位置依赖性.上述结果可为SiGe HBT单粒子效应的抗辐射加固提供有力的指导依据. 相似文献
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单粒子锁定效应容易引起星载遥感仪器产生故障。针对空间高能粒子辐射环境诱发的偏振遥感相机性能退化问题,利用高能重离子和皮秒脉冲激光对星载偏振成像仪选用的模拟前端信号处理器开展了试验研究,获得了此类器件的单粒子锁定特点,为工程设计及试验评估提供了参考。试验结果显示:偏振成像仪选用的模拟前端信号处理器对重离子诱发的单粒子锁定比较敏感,单粒子锁定LET阈值处于4.4~13.4 MeV·cm2·mg?1之间。针对模拟前端芯片LET阈值偏低的问题,提出了一种模拟供电端和数字供电端串联大功率防闩锁限流电阻和在轨定时开关机的设计方法。试验结果表明,该方法可有效避免器件单粒子锁定造成的器件过流烧毁及仪器失效等故障。研究结果可为星载偏振相机用模拟前端信号处理器抗辐射加固设计和单粒子地面模拟实验方法的建立提供技术基础与保障。 相似文献
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阐述了脉冲激光沉积法的基本原理、特点及其应用。分别介绍了超快脉冲激光沉积法、双光束脉冲激光沉积法、脉冲激光气相沉积法、脉冲激光液相沉积法、脉冲激光诱导晶化法、直流放电辅助脉冲激光沉积法、脉冲激光分子束外延法的原理及最新研究成果。展望了脉冲激光沉积法制备无机发光薄膜的发展趋势。 相似文献
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分析了脉冲电流对金属沉积过程的影响.采用双脉冲电镀法,进行了在光电器件管壳上镀镍和镀金实验,并通过适当控制其正负脉冲电流密度、导通及关断时间等参数,获得了光亮、结晶致密、耐高温、抗腐蚀性能好的镀层. 相似文献
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《Applied Superconductivity》1999,6(6):247-257
A new design concept of the axisymmetric magnet system generating the very high pulsed magnetic field which is superimposed on the bias magnetic field of the superconducting magnet is presented. The pulsed magnet consists of two coaxial coils which are wound in opposite directions. The geometry of both pulsed coils, i.e. the working (inner) one and the compensating (outer) one is designed in such a way that the mutual coupling between the small pulsed magnet and the outer superconducting magnet is practically zero. This configuration prevents the rise of the high induced voltage on the current leads of the superconducting magnet when the pulsed magnet is being energised, hence resulting naturally in protection of the system (superconducting magnet and the current source) against possible damage. Further, it is predicted that the stray field of the pulsed magnet, which gives rise e.g. to the eddy currents in the winding of the superconducting magnet, is considerably decreased. The simple theory enabling the design of the geometry of the compensating pulsed coil is derived. The advantages of this new concept are demonstrated on the results of the theoretical analysis using, as an example, one of the pulsed coils that were designed and fabricated in the Clarendon Laboratory, in connection with the Oxford Instrument superconducting magnet (Clarendon hybrid outer) which can generate a steady magnetic field up to 10 T in a room temperature working space with a diameter of 240 mm. 相似文献
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Yeu-Haw Yang Chung-Yu Wu 《Electron Devices, IEEE Transactions on》1989,36(7):1336-1347
A criterion for transient latchup of p-n-p-n structures initiated by current pulses is described. Based on the circuit-orient model, the terminal currents and voltages of the transistors as a function of the pulsed triggering currents are characterized, and the charge storage within p-n-p-n structures is investigated. It is found that, to maintain the regeneration process, the change of charge stored in junction depletion capacitances of a p-n-p-n structure must be greater than a certain value independent of the triggering currents. Thus, the criterion is constructed in terms of the constant charge storage within a p-n-p-n structure. Applying the criterion, latchup immunity against pulsed triggering currents can be evaluated with respect to process and device parameters. Both SPICE simulations and experimental results confirm the validity of the proposed transient criterion. It is found that the large transit time of bipolar transistors and large well-substrate junction depletion capacitance lead to higher latchup immunity against pulsed triggering currents 相似文献
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对脉冲CO2激光在不同重频模式下损伤K9玻璃进行了实验研究。采用输出能量为10 J,脉宽为90 ns,重复频率在100 Hz至300 Hz之间连续可调的脉冲CO2激光器,对K9玻璃样品进行了激光损伤实验,观察到两次不同重频条件下样品的损伤形貌。实验结果表明,重频越高,对样品的损伤程度就越严重;应力损伤成为K9玻璃激光损伤的最主要的原因,在重频强激光的辐照下,K9玻璃表面出现强烈的等离子体闪光,伴随明显的熔融气化破坏,并形成等离子体爆轰波。爆轰波对玻璃材料产生了严重的力学冲击作用,这种应力作用足以对K9玻璃造成毁灭性破坏。运用有限元分析对激光辐照K9玻璃的温度与应力分布进行仿真,其计算结果与实验基本吻合。 相似文献