Effect of power supply parameters on the discharge characteristics and sterilization efficiency of magnetic driven rotating gliding arc

The plasma sterilization is a new generation of high-tech sterilization method, with the characteristics of fast, safe and pollution-free, widely used in medical, food and environmental protection fields. Home air sterilization is an emerging field of plasma application, which puts higher requirements on the miniaturization, operational stability, and operating cost of plasma device. In this paper, a novel magnetic driven rotating gliding arc (MDRGA) discharge device was used to sterilize lactobacillus fermentation. Compared to the traditional gas driven gliding arc, this device has a simple structure and more stable gliding arc. Simulation using COMSOL Multiphysics showed that adding permanent magnets can form a stable magnetic field, which is conducive to the formation of gliding arcs. Experiments were conducted on discharge performance, ozone concentration, and sterilization effect under different power supply parameters. The results revealed that the process of MDRGA can be divided into three stages: starting, gliding and extinguishing. The appropriate voltage was the key factor for stable arc gliding, and both high and low voltages were not conducive to stable arc gliding and Ozone production. For this experimental setup, the sterilization effect was best at 6.6 kV. High modulation duty ratio was beneficial for stable arc gliding, however, when the duty ratio exceeds a certain value, the improvement in sterilization effect was slow. So, considering the sterilization effect and energy factors comprehensively, for this experimental device, we choose 80% as the optimal modulation duty ratio.