Abstract
One of the failure related to gas-insulated switchgear is caused by the poor contact between conductors, causing breakdown between the contact and the wall of chamber, initiated with the small discharge due to the poor contact.
In this paper, the modeled experimental apparatus for contact portion of the gas-insulated switchger assumed a rod-to-plane gap with small arc current. The influence of the arc current on the breakdown into the chamber was investigeted experimentally, and the breakdown mechanism between the contacts and the wall was studied.
It was cleared that the breakdown voltage between the contact and the wall decreased by increasing the current, and the small arc current in the contact portion played an important role on the breakdown between the contact and the wall.
The reduction ratio of the breakdown voltage increased with increasing gap length of the small gap. The breakdown voltage was different depend on the duration of the small arc current.
