3-MHz High-Voltage Pulse Generator With Novel Multilevel LC Resonant Network for Adjustable Pulsewidth

Voltage pulses with high repetition rates and short rise times exhibit promising prospects in applications of electroporation induced by nanosecond pulsed electric fields, owing to their unique intracellular effects. Generators using diode opening switch (DOS) can generate ultrashort nanosecond pulses with high voltage gain. However, the inherent semicontrolled nature of diodes presents challenges to the adjustability of pulsewidth in DOS generators. Moreover, the maximum achievable repetition frequency is theoretically limited by the resonant period. In this article, a novel modulator comprising multistage linear resonant loops is proposed. This topology enables the adjustment of pulse duration in diode-based LR discharging circuits. Furthermore, the developed approach of multiple modules frequency superposition not only surpasses the theoretical upper limit of repetition rate, but also exhibits improved energy conversion efficiency when compared to traditional DOS circuits. The experimental results indicate that the prototype outputs pulses with amplitude of 2.8 kV and duration ranging from 6.9 to 20.3 ns, while achieving a 55.6% improvement in energy transfer efficiency compared to conventional structures.