基于SOS和LTD技术的高重复频率脉冲发生器

提出了磁饱和直线变压器驱动源(LTD)泵浦半导体断路开关(SOS)产生高重复频率短脉冲的技术路线。利用LTD初次级线圈为单匝同轴结构和磁芯可饱和的特点,实现快速反向泵浦SOS,通过多级LTD模块叠加获得高电压输出。采用射频金属氧化物场效应晶体管(RF MOSFET)作为LTD初级电路的主开关,将SOS正向泵浦电流脉冲时间降至数十ns,泵浦电流脉冲重复频率最高可达MHz。最终研制出一台基于SOS的10级磁饱和LTD型脉冲发生器,输出电压约11kV,电流220A,脉冲宽度约2ns,重复频率为20kHz。实验验证了磁饱和直线脉冲变压器泵浦SOS产生高重复频率短脉冲的技术路线可行。

Repetitive frequency pulsed generator based on semiconductor opening switch and linear transformer driver

A repetitive frequency and nanosecond-pulsed generator based on the semiconductor opening switch (SOS) technology is developed, in which the pulse compression unit is realized by several radio frequency (RF) MOSFETs and a saturable linear transformer driver (LTD). The RF MOSFETs are employed to obtain the forward pumping current pulses with the duration of decades of nanoseconds; the saturable LTD is to raise the pulse voltage, compress the pulse width and pump SOS reversely. The SOS assembly cuts off the reverse current in a few nanoseconds that leads to narrow output pulse formation on an external load. The experimental results show that the output pulses of the SOS generator are amplitude 11 kV and width 2 ns on a 50 resistive load. Due to the repetitive ability of RF MOSFETs, the generator can operate at repetitive frequency of larger than 20 kHz.