Diffuse Discharges in Open Air Sustained by Microsecond and Nanosecond Pulses

摘要

Some discharge images are presented to illustrate the discharge characteristics of various excitations with s-pulse and ns-pulse in open air. Saws or knife blades of cm in length are used for high voltage (HV) electrodes, and one metal plane is used as earthed electrode. These typical images show that the diffuse and plume-like discharge along the HV electrode can be sustained by microsecond or nanosecond pulses. Compared with s-pulse excitation, ns-pulse is better for sustaining the diffuse discharges. Furthermore, the discharge from a diffuse mode to a combined mode of diffuse and filamentary discharges is in response to the decrease of the air gap spacing when the s-pulse is applied.