介绍了面向Z箍缩驱动聚变裂变混合堆（Z-FFR）能源的重复频率800 kA快上升沿的线性变压器驱动源（LTD）模块的设计和测试。LTD模块由34组RLC电路组成,每组包含2台100 kV/40 nF脉冲电容器、1个多间隙气体开关和非晶磁芯。研制的模块可以在匹配水电阻负载上以0.1 Hz的重复频率输出上升沿约100 ns的800 kA的电流脉冲。采用了一个高压触发信号来触发整个模块的新触发方式,将外触发信号通过模块内布置的角向传输线等网络同时到达并触发所有的高压开关,实验结果表明采用一路140 kV、25 ns前沿的触发脉冲可以可靠地触发整个模块。为了保证LTD模块每10 s输出一个80 kV/800 kA的电流脉冲,非晶磁芯的去磁复位采用了一个5.2 kA、脉宽30 μs的电流脉冲,其运行频率为0.1 Hz。模块采用的多间隙气体开关运行寿命超过10 000次,其抖动小于3 ns。

Due to the coupling problem, the output efficiency of the accelerating unit for the dielectric wall accelerator is reduced. With electromagnetic field simulation software based on FDTD method, the multi-plate Blumlein lines loading the high gradient insulator(HGI) is analyzed. The simulation includes one and three groups of 1-stage and 15-stage Blumlein line(BL) respectively loading HGIs. The results show more parallel electrodes in multi-BLs bring itself a large coupling capacitance, which leads to a slower rising edge and a lower amplitude. The output efficiency drops when three groups of multi-BLs work together because the adjacent group of multi-stage-BLs become a coupling capacitor and split current seriously. At the same time, the adjacent group of multi-stage BLs also discharge and affect output efficiency. A preliminary optimization is studied. By rotating every BL stages a certain angle to reduce the effective opposite area of parallel electrodes, the group of multi-BLs decreases its own coupling capacitance, and some benefit achieved. However, it requires further verification whether the optimization can reduce the coupling capacitance between the BL modules.