Manipulating the discharge pulse number in an atmospheric helium dielectric barrier discharge with multiple current pulses per half cycle

We report a systematic numerical study regarding the control of discharge pulse number in an atmospheric helium dielectric-barrier discharge with multiple current pulses per half cycle. The results indicated that by replacing the original sinusoidal applied voltage with a peak-levelled one, the manipulation of current pulse number in each discharge half cycle could be achieved, and the initial moment of flat-top stage t0, which reflects the duration of peak-levelled applied voltage, was set to be the controlling parameter. With the increase of flat-top duration, the current pulse number per half cycle decreased monotonously from the original value to zero. In this process, the current amplitude elevated, the peak phase delayed, and the energy efficiency in terms of electron production enhanced. Further analyses revealed that the above alterations in discharge performance were not caused by changes in seed electron level of the discharge, but by the variations in discharge current components and surface charge level. Finally, based on the criteria of pulse number alteration, a preliminary analytical method was proposed to switch the original multiple-current-pulse discharge into a single-current-pulse one. The results obtained in this work are expected to help achieve the mode manipulation and stabilization of the discharge in industrial application scenarios.