Li Jiangtao, Zhao Zheng, Sun Yi, Liu Yuhao, Ren Ziyuan, He Jiaxin, Cao Hui, Zheng Minjun
School of Electrical Engineering, Xi'an Jiaotong University, Xi'an 710049, China.
Rev Sci Instrum. 2017 Mar;88(3):033507. doi: 10.1063/1.4978650.
Numerous applications driven by pulsed voltage require pulses to be with high amplitude, high repetitive frequency, and narrow width, which could be satisfied by utilizing avalanche transistors. The output improvement is severely limited by power capacities of transistors. Pulse combining is an effective approach to increase the output amplitude while still adopting conventional pulse generating modules. However, there are drawbacks in traditional topologies including the saturation tendency of combining efficiency and waveform oscillation. In this paper, a hybrid pulse combining topology was adopted utilizing the combination of modularized avalanche transistor Marx circuits, direct pulse adding, and transmission line transformer. The factors affecting the combining efficiency were determined including the output time synchronization of Marx circuits, and the quantity and position of magnetic cores. The numbers of the parallel modules and the stages were determined by the output characteristics of each combining method. Experimental results illustrated the ability of generating pulses with 2-14 kV amplitude, 7-11 ns width, and a maximum 10 kHz repetitive rate on a matched 50-300 Ω resistive load. The hybrid topology would be a convinced pulse combining method for similar nanosecond pulse generators based on the solid-state switches.
许多由脉冲电压驱动的应用要求脉冲具有高幅度、高重复频率和窄宽度,利用雪崩晶体管可以满足这些要求。输出的提升受到晶体管功率容量的严重限制。脉冲合成是一种在仍采用传统脉冲生成模块的情况下提高输出幅度的有效方法。然而,传统拓扑存在缺点,包括合成效率的饱和趋势和波形振荡。本文采用了一种混合脉冲合成拓扑,它结合了模块化雪崩晶体管马克思电路、直接脉冲相加和传输线变压器。确定了影响合成效率的因素,包括马克思电路的输出时间同步、磁芯的数量和位置。并联模块的数量和级数由每种合成方法的输出特性确定。实验结果表明,在匹配的50 - 300Ω电阻负载上,该拓扑能够产生幅度为2 - 14 kV、宽度为7 - 11 ns且最大重复频率为10 kHz的脉冲。对于基于固态开关的类似纳秒脉冲发生器,这种混合拓扑将是一种可靠的脉冲合成方法。