Interrupted current magnitude is the key parameter for arc production in medium and high voltage systems. The magnitude of the arc developed across a gap depends on the magnitude of the interrupted current. This means that keeping the anticipated arc to a low value can be achieved by reducing the anticipated interrupted current. The significance of this study is found in arc control in medium and high voltage systems where reduction in the interrupted current is shown to be the best technique. The method used was mathematical analysis of the key arc parameters. The major findings were that: the processes that result in electric arc production namely: field emission, thermionic emission and increase in mean free path, are current driven; by skin effect, effective conductor resistance is more for AC than for DC systems; proximity effect increases the effective conductor resistance; the system voltage is not responsible for re-establishing the arc during circuit breaker opening rather, it is the restriking voltage that is capable of doing this. The phenomena often misconstrued by many to be voltage driven, is therefore properly put in perspective in this paper as current driven.

Full text: IJEIR_2442_FINAL.pdf