Solid-State Marx Generator With Sharpening Capacitor

The effect of sharpening capacitor on the rise time of pulsed power generator has been studied recently, suggesting that a capacitor connected in parallel to the resistive load may help in reducing the rise time of the output. In addition, a bias voltage applied on this capacitor may further reduce the rise time. In this article, a solid-state Marx generator has been used to demonstrate this effect. A ten-module Marx generator circuit using power MOSFETs was used. Experiments were carried out by comparing the output rise time, defined by the time between 10% and 90% of the peak voltage, obtained with and without the sharpening capacitor. With a charging voltage of 800 V, the Marx generates an output of ~7.8 kV on a 40
$\Omega $
load. Using a sharpening capacitor of 520 pF, the rise time is reduced from ~140 to ~120 ns. Furthermore, by applying a bias voltage of −2 kV, the rise time is shortened to ~83 ns, a ~41% reduction from that obtained without the sharpening capacitor.