Early stages of discharge development on insulating spacers in gases - a photographic study

摘要

All HV power apparatus have insulating spacers stressed by the full system operating and transient voltages. The surface flashover characteristics of support spacers often determine the overall dimensions of HV equipment. It is known that in many installations, the apparatus insulation is subjected to transient overvoltages with nano-second risetime. An understanding of the early stages of discharge development on spacers is, therefore, important for insulation system design. Pre-breakdown discharge development on spacers at low operating pressures (vacuum) has received considerable attention [1-3]. The reported work in high pressure gases, however, is not very extensive [4-6].