Effects of Repetition Frequency and Rising Edge Time on Uniformity of Air Dielectric Barrier Discharge

Nanosecond pulse excited dielectric barrier discharge (DBD) with fast rising edge and high breakdown voltage can enhance the discharge uniformity and reactivity. In this paper, the discharge image and the voltage-current waveforms of the nanosecond pulsed air DBD with grounded ITO electrode are measured to reveal the effects of the pulse repetition frequency (PRF) and rising edge time on the discharge uniformity. The discharge uniformity is quantitatively analyzed by the observed discharge images and the gray analysis method. The results show that when the PRF is less than 5kHz, the discharge is uniform. With the frequency increases, the residual charged particles will lead to the deterioration of the electrical field and decrease the uniformity. The rapid voltage slew rate can increase the reduced electric field strength in space, which promotes the electron avalanche merging and increase the discharge uniformity. It is also found that the increase of PRF would lead to the increase of the peak values of the gap voltage and the discharge current first (from 500Hz to 3kHz) and then decrease. The increase of pulse rising time leads the decrease of the peak values of the gap voltage and the discharge current. The results contribute to the realization of uniform and reactive plasmas.