Design and Performance of a Ferrite Transmission Line Sharpener for Trigger Generator Used in FLTD

Abstract

Tens of thousands of gas switches in fast linear transformer driver (FLTD) need to be switched ON synchronously, which requires gas switch triggers with fast rise time and low jitter. At present, the pulse rise time of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\sim 100$ </tex-math></inline-formula> -kV gas switch trigger is often sharpened by a gas switch. Although the gas switch sharpener can reduce pulse rise time, it is difficult to control the pulse jitter because of the dispersion of gas discharge. Using a ferrite nonlinear transmission line to steepen pulse rise time has been widely used in high-power microwave fields. In this article, a ferrite transmission line is proposed to replace the gas switch sharpener. By establishing the simulation model of the ferrite transmission line, the effects of pulse amplitude, transmission line length, and structural parameters on the sharpening rise time are analyzed. An experimental platform was established to test the sharpening performance of two different structural ferrite transmission lines. The test results show that the ferrite transmission lines can reduce the trigger pulse rise time from 124 ns to less than 16 ns, and the jitter of the whole trigger device is less than 2.5 ns, which can be used to replace the gas switch sharpener.