Nanosecond Repetitively Pulsed Discharge of Point–Plane Gaps in Air at Atmospheric Pressure

Atmospheric-pressure gas discharge excited by high-voltage pulses with fast rise time and short duration has attracted significant attention for various applications. In this paper, discharges are generated in a highly nonuniform electric field by point-plane gaps in air at atmospheric pressure by a solid-state repetitive nanosecond-pulse generator. Under different experimental conditions, the applied voltage, discharge current, and discharge image are recorded. The results show that there are four typical discharge fashions, i.e., corona, diffuse, filamentary, and diffuse-to-filamentary modes. With the variation of air gap spacing or applied pulse repetition rate, the difference among various discharge modes can be found in discharge current and luminous images. Moreover, the effects of repetition rate and air gap spacing on electrical characteristics and discharge modes are investigated. It is seen that the discharge tends to transit from the diffuse mode to the filamentary mode with the reduction of air gap spacing or the increase of repetition rate. In addition, the experimental results are discussed according to the electrical parameters and discharge images.