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Transport behaviour of residual charges in repetitively pulsed streamer evolution in gas gap and along solid surface

Evolution mechanism and transport behaviour of residual charges in repetitively pulsed streamer discharge were investigated based on pulse-sequence resolved electrical and optical measurements in nitrogen rod-plane gap and along dielectric surface. The number of applied pulses before breakdown illustrates nonlinear dependences on the gas pressure and the pulse repetition frequency (PRF). With increasing PRF, the streamer discharge in nitrogen gas gap exhibits a three-stage transition process from an intermittent mode to a successive mode. In the surface discharge, a clear decrease in the inception moment and a slow rising stage are identified at 1 kHz. The average propagation velocity decreases and then saturates with increasing PRF. The space-charge-dominated memory effect mechanism is analysed based on preliminary fluid simulation and the distribution of spatial electric field.