Control and Stabilization of Centimeter Scale Glow Discharge in Ambient Air Using Pulse-Width Modulation

Re-pulsing glow discharges in atmospheric-pressure air were experimentally investigated using a push-pull generator with pulse-width modulation. Discharges were ignited as a spark-glow discharge sequence and sustained in a glow regime after ignition in a gap of 2 cm and characterized by current and voltage measurements, as well as by optical emission spectroscopy. It was found that at a certain range of parameters, the discharge could be stabilized even in the presence of external airflow. It was demonstrated that the type of discharge and total power dissipated in the plasma volume could be precisely controlled by pulse-width modulation. Additionally, it was confirmed that the rotational temperature varied across a wide range (1640-2440 K) by using pulse-width modulation with gas-flow control, when vibrational temperature was around 4610 ± 770 K. The generation of stable glow discharge in the presence of gas flow with a wide range of parameters that could be precisely controlled by pulse-width modulation looks promising for use in energy-efficient gas conversion.