Influence of electrode curvature of predischarge phenomena and electric strength at 50 Hz of a vacuum gap

The influence, in sphere-plane and ring-ring arrangements, of electrode curvature and microprofile on electron emission phenomena as well as on the electric strength of vacuum gaps is discussed. Improvement of the electrode microprofile was obtained by utilization of electropolishing technology. The nature of that technology is selective smoothing of the microneedles on the electrode surface. Optimum values of the electrode radius of curvature for various electrode distances have been determined. It was found that electropolished electrodes of various curvature resulted in increasing the electric strength of a vacuum gap by approximately 20-100%.