The Research on Megahertz High-Voltage Pulsed Power Supply Based on Delay Drive Control

Abstract

The nanosecond pulse generator, which works continuously at megahertz repetition rate, plays an important role in high-energy accelerators, electromagnetic biological effects, pulse laser modulation, and other fields. However, due to its own frequency limitation, a single SiC MOSFET switch cannot reach the required frequency. The use of multichannel MOSFET will make the drive control become more complex, thus facing more serious electromagnetic interference at high frequency. In this article, the method of pulse superposition is used to realize the output of megahertz pulse. At the same time, a delay driving circuit applied to the megahertz pulsed power supply is proposed. This solid-state hardware delay is carried out by using the deep saturation principle of the transistor, and multiple switches can be driven by only one signal. To verify its working principle, the experimental prototype is built which is composed of two modules. A single module contains two switches in parallel to achieve frequency superposition. Two modules are connected in series to increase the output voltage. The results show that the circuit can work stably at 1-MHz frequency. The repetitive pulse output with amplitude of 1.5 kV and pulsewidth of 320 ns can be obtained on the resistive load. Adding a truncated signal under a capacitive load, it can also achieve a voltage output with frequency of 1 MHz.