Author Affiliations
Abstract
1 College of Advanced Interdisciplinary Studies, National University of Defense Technology, Changsha 410073, China
2 Nanhu Laser Laboratory, National University of Defense Technology, Changsha 410073, China
Radio frequency/microwave-directed energy sources using wide bandgap SiC photoconductive semiconductors have attracted much attention due to their unique advantages of high-power output and multi-parameter adjustable ability. Over the past several years, benefitting from the sustainable innovations in laser technology and the significant progress in materials technology, megawatt-class output power electrical pulses with a flexible frequency in the P and L microwave wavebands have been achieved by photoconductive semiconductor devices. Here, we mainly summarize and review the recent progress of the high-power photonic microwave generation based on the SiC photoconductive semiconductor devices in the linear modulation mode, including the mechanism, system architecture, critical technology, and experimental demonstration of the proposed high-power photonic microwave sources. The outlooks and challenges for the future of multi-channel power synthesis development of higher power photonic microwave using wide bandgap photoconductors are also discussed.
high-power photonic microwave wide bandgap photoconductive semiconductor devices linear modulation multi-parameter adjustable microwave generation multi-channel power synthesis Chinese Optics Letters
2024, 22(1): 012501
强激光与粒子束
2023, 35(10): 105001
1 国防科技大学 前沿交叉学科学院，高功率微波技术研究所，长沙 410072
2 脉冲功率激光技术国家重点实验室，长沙 410072
通过理论计算、数值仿真和实验验证的方法，研究了一台峰值功率数十GW、重复频率5 Hz的重复频率高功率脉冲驱动源，命名为“HEART-50”。该脉冲驱动源由充电电源、初级开关、脉冲形成线、主开关、阻抗变换线，以及假负载构成。首先介绍了HEART-50重复频率高功率脉冲驱动源整体设计思路；其次，对基于混合液体介质的高功率脉冲形成线和气体介质主开关进行了数值分析，并对其全电路工作能力进行了仿真分析；最后，对研制的HEART-50重复频率高功率脉冲驱动源进行了实验验证。结果表明，脉冲驱动源能够输出峰值电压520 kV，脉冲宽度约90 ns，脉冲上升沿小于25 ns，重复频率5 Hz的准方波电脉冲，峰值电功率约为25.3 GW，且具有较好的运行稳定性。
脉冲功率技术 高功率 重复频率 HEART-50 pulsed power technology high power repetitive rate HEART-50 强激光与粒子束
2022, 34(9): 095014
强激光与粒子束
2022, 34(9): 095002
1 国防科技大学 前沿交叉学科学院，长沙 410073
2 脉冲功率激光技术国家重点实验室，长沙 410073
脉冲功率技术的重要发展方向是高功率密度、紧凑小型化和高稳定可靠。液体介质由于具有绝缘强度高、易流动、快恢复、散热性好等方面的特点，广泛应用于脉冲形成线型紧凑小型脉冲功率源的电容储能器件作为储能介质。主要围绕紧凑小型脉冲功率源ARC系列的技术难题，开展了关键技术、系统研发及其工程应用等方面的工作。首先，提出了基于液体介质和慢波结构的形成线，采用场均匀和绝缘配合技术，研制出紧凑小型脉冲功率源ARC-01和ARC-02，输出功率1～2 GW、脉冲宽度5～30 ns、重复频率1～100 Hz，紧凑化水平较国际先进同类装置最多提高了2倍。之后，以凑小型脉冲功率源为核心搭建液体介质击穿测试平台，针对变压器油、蓖麻油、甘油、碳酸丙烯酯等常见液体介质，开展了微秒脉冲击穿特性研究，采用统计分析方法建立了数据库，以“小成本”换取“高可靠性”；并采用超高速光学诊断方法，将击穿瞬间流注、冲击波、亚微观断裂面产生、传播、截止过程与张力理论结合，建立了液体介质击穿物理模型。最后，成功将紧凑小型脉冲功率源应用于驱动宽带/窄带微波产生、碳纤维阴极稳定性及寿命测试。
脉冲功率源 脉冲功率技术 紧凑 小型 液体介质 pulsed power source pulse power technology compactness small-sized liquid dielectric 强激光与粒子束
2022, 34(7): 075016
强激光与粒子束
2022, 34(7): 075008
1 国防科技大学 a.前沿交叉学科学院，湖南长沙 410073
2 b.脉冲功率激光技术国家重点实验室，安徽合肥 230037
磁开关因其优异的特性而被广泛用于固态脉冲功率调制器中，基于磁开关的多脉冲发生器的同步运行对产生更高功率的脉冲具有重要意义。与其他高功率开关相比，磁开关存在一种基于磁耦合机制的被动同步技术。通过耦合线圈相连的磁开关能够被动地减少磁开关之间的抖动，使多个磁开关趋于同步运行。设计了一个两路磁开关同步运行实验，实验结果显示差异为2.2 μs和 0.3 μs的 2个脉冲在引入磁耦合之后差异分别降至 0.6 μs和 0.1 μs，表明该磁耦合技术能成倍减少两台装置的输出抖动。此外，还针对磁开关同步运行过程及磁耦合机制进行了合理分析，并开展了基于 PSpice的磁开关同步电路仿真研究，提出了一种改进型回转器 -电容等效电路模型，该电路模型能有效地重现实验结果，为更深入理解磁开关同步运行技术及分析磁耦合机制奠定了基础。
功率合成 磁开关同步 磁耦合 回转器 -电容模型 power combination synchronization of magnetic switches magnetic coupling gyrator -capacitor model 太赫兹科学与电子信息学报
2021, 19(1): 170
强激光与粒子束
2020, 32(2): 025003
Author Affiliations
Abstract
1 College of Advanced Interdisciplinary Studies, National University of Defense Technology, Changsha 410073, People's Republic of China
2 State Key Laboratory of Pulsed Power Laser Technology, National University of Defense Technology, Changsha 410073, People's Republic of China
This paper provides a review of the compact intense electron-beam accelerators (IEBAs) based on liquid pulse forming lines (PFLs) that have been developed at the National University of Defense Technology (NUDT) in China. The history and roadmap of the compact IEBAs used to drive high-power microwave (HPM) devices at NUDT are reviewed. The properties of both de-ionized water and glycerin as energy storage media are presented. Research into the breakdown properties of liquid dielectrics and the desire to maximize energy storage have resulted in the invention of several coaxial PFLs with different electromagnetic structures, which are detailed in this paper. These high energy density liquid PFLs have been used to increase the performance of IEBA subsystems, based on which the SPARK (Single Pulse Accelerator with spark gaps) and HEART (High Energy-density Accelerator with Repetitive Transformer) series of IEBAs were constructed. This paper also discusses how these compact IEBAs have been used to drive typical HPM devices and concludes by summarizing the associated achievements and the conclusions that can be drawn from the results.
High-power microwave (HPM) Intense electron-beam accelerator (IEBA) Pulsed power technology (PPT) Pulse forming line (PFL) Fluid of high energy density De-ionized water Glycerin Matter and Radiation at Extremes
2018, 3(6): 278
国防科技大学 前沿交叉学科学院, 长沙 410073
磁开关因其独特的饱和导通机制而在脉冲功率技术领域应用广泛, 利用磁开关饱和前后电感差异大的特点, 可以将其用作撬断开关来陡化脉冲后沿。利用金属氧化物压敏电阻的稳压特性, 能在负载上得到具有一定平顶的脉冲准方波, 进而可通过改变磁开关的伏秒积来进行脉宽调整。提出一种脉宽可调的高压脉冲发生器技术方案, 利用压敏电阻产生高压脉冲准方波, 用磁开关作为撬断开关来陡化脉冲后沿, 并通过改变磁开关复位电流的大小来控制磁开关的复位深度, 进而实现脉宽可调。首先进行了理论分析及软件模拟研究, 然后基于模拟结果开展了初步实验研究。初步实验得到的负载电压波形后沿小于30 ns, 脉宽可调范围大约30%, 验证了磁开关的后沿陡化效果以及用于脉宽调整的可行性。
高压脉冲发生器 磁开关 脉宽可调 撬断开关 压敏电阻 pulse generator magnetic switch adjustable pulse width pry-off switch metal-oxide varistor 强激光与粒子束
2018, 30(10): 105001
