Direct-current breaker for high power for connection into a direct-current carrying high-voltage line

摘要

A high power d.c. breaker for connection into a d.c. carrying high-voltage line (L), has two normally closed and electrically series-connected mechanical breaks (BSI, BSII) adapted to be traversed by the line current (I) and to be opened for breaking the current. A capacitor (CB) is connected in parallel with the series connection of the breaks. A semiconductor member (HO) is connected in parallel with one of the breaks (BSI). Upon opening the breaks, a control member (SO) controls the semiconductor member such that a zero crossing of the current through the second break (BSII) is obtained, whereby the line current (I) is commutated over to the capacitor. (FIG.