Space Charges Produced in a Rod-to-Plane Gap under Impulse Voltages

Abstract

The space charges produced in a hemispherical rod-to-plane gap in air are measured under the impulse voltage application by the use of a probe, which is constructed by a sphere near the gap space. The space charges accompanied with the streamer occurrence are about 20～200 nC and 5～60 nC for the positive and negative voltage application, respectively. The maximum space charges over the whole process to the flashover are 20～260 nC and 20～60 nC for the positive and negative voltage application, respectively. After the flashover occurrence, the space charges remain in the gap space, the values being below 200 and 30 nC for the positive and negative voltage application, respectively.