A Polarity-Adjustable Nanosecond Pulse Generator Suitable for High Impedance Load

Abstract

This article presents a new method for forming nanosecond short pulse on high impedance load using the turnon and turn-off delays of dual Marx. The generator combines advantages of the traditional solid-state Marx generator's modular stacking design to easily stack high-voltage pulse, flexible pulsewidth, and compact size. It can output unipolar or bipolar pulses by controlling the driving signal of each Marx. And the delay time between bipolar pulses can be flexibly adjusted. The dual Marx of the pulse generator is designed by the same seven-stage module stack. The SiC-MOSFET with fast turn-off capability and high repetition rate is used as the main switch, which has superior performance under high-frequency conditions. Through theoretical analysis and prototype test, the generator can generate voltage amplitude ±5 kV under 2-kΩ noninductive resistance load, pulsewidth 10-30 ns continuously adjustable, and the delay time of positive and negative nanosecond pulses is 100-400 ns. This high-voltage nanosecond pulse generator has a repetition frequency of up to 1 MHz in the burst.