非线性铁氧体传输线的脉冲陡化作用

阐述了非线性铁氧体传输线的工作机理,并给出了等阻抗的设计方法。针对已有重复频率脉冲功率源输出脉冲特点,设计了工作重复频率可达10kHz的铁氧体传输线,并可实现将前沿ns级的高压脉冲陡化至几百ps。采用多种NiZn铁氧体磁芯开展陡化实验,研究了磁芯参数、铁氧体传输线长度及外加励磁场等因素对陡化效果的影响,得出采用高饱和磁化强度的磁芯可以获得更快的脉冲前沿;采用小磁芯可以加快输出脉冲前沿,但需要的铁氧体长度更长;外加轴向励磁对陡化前沿也具有促进作用,但励磁场并非越大越好,而是存在一个最佳范围。目前,根据实验结果优化后,经铁氧体传输线可将脉冲前沿从4ns陡化至450ps,且输出脉冲电压峰值39kV,基本实现了高重复频率、高功率及快脉冲输出。

Pulse sharpening effect of nonlinear ferrite-loaded transmisstion line

A nonlinear transmission line-based pulse-sharpening system with output pulse of high voltage into 50 for repetitive operation is developed. This paper describes the theory and design procedures of ferrite-loaded transmission line which is used to produce sub-nanosecond rise time electrical pulse with high power. The design parameters based on ferrite-loaded line are presented. In experiment, different factors on the fact of sharpening are analyzed. The experiment results show the pulse sharpening effect varies with different ferrite materials. It helps the final selecting of the most efficient ferrite material, the ferrite with higher saturation magnetization. The experiment results indicate that the axial bias is very important for the pulse sharpening. There is a best value of the axial bias for the fastest front of pulse. After optimization, an output pulse of 450 ps, 39 kV is obtained at load for high repetitive operation.