Fast and flexible solid-state linear transformer driver for plasma discharge based on metal oxide semiconductor field effect transistor.

Abstract

A pulsed power supply with a short rise time and high repetition frequency is favorable to driving diffusive plasma for strongly oxidizing radical (O3, OH) generation and increasing the system's energy efficiency. In this paper, a 10-stage solid-state linear transformer driver (LTD) with a nanosecond rise time is developed to drive plasma for wastewater treatment. To decrease the rise time, a control system with low jitter is developed to improve the synchronization of pulses using an optocoupler isolation chip. A 10-stage LTD with a rise time of 6.2ns is realized in the case that the rise time of the single-stage LTD is 5.4ns. The results show that the LTD can generate pulses on a 300Ω resistive load with a repetition frequency of 10kHz, an amplitude of 8.80kV, an overshoot less than 3.97%, and a reverse overshoot less than 4.82%. The rise time (6.2-33.0ns), the pulse width (35.9-200.0ns), and the fall time (10.5-27.6ns) can be adjusted flexibly and independently by controlling the drive signals of metal oxide semiconductor field effect transistors. The pulsed generator is utilized to drive plasma in the needle-water electrode system. The preliminary experimental results show that the plasma includes abundant oxygen atoms and hydroxyl radicals with high activity, and it is suitable for wastewater treatment.