Restrike characteristics on capacitive current breaking in vacuum

Restrike characteristics on a capacitive current breaking in a vacuum have been investigated. In a small capacitive current breaking test, double voltage from commercial voltage (peak) would be applied between contacts of a VI. The configuration of contacts and the current conditioning dependence of VI practical samples with axial magnetic field contacts were investigated under a simulated capacitive current breaking test. Minimum restrike voltage decreased and voltage dispersion was high due to the presence of slits on the contacts. On the other hand, the minimum restrike voltage increased and restrike voltage dispersion was low due to current conditioning. By practical tests and standardized tests, a new 72kV VI and dry air insulated VCB has been developed.