| 摘要 |
<p>To obtain a direct-current circuit breaker that is capable of cutting off a fault point at a higher speed and that can achieve downsizing and cost reduction. The direct-current circuit breaker includes a bridge circuit 6 that is configured by connecting two series circuits 6a and 6b in anti-parallel with each other, each of the series circuits being configured from a reactor 2 and a commutation unit 3 that includes a capacitor 5, a first blocking unit 1 that is connected between connection points, each of which is between the reactor 2 and the commutation unit 3 in each of the series circuits 6a and 6b, that is in a closed state at a normal time when a steady-state current flows through a DC line, that is controlled so as to be opened after occurrence of a fault in the DC line, and that is disconnected at a current-zero point at which a current flowing through the reactors 2 and a current flowing through the commutation units 3 cancel each other out, and a second blocking unit 4 that is connected to the bridge circuit 6 in series, that is in a closed state at a normal time, that is controlled so as to be opened after the first blocking unit 1 is disconnected, and that is disconnected at a current-zero point at which currents flowing respectively through the series circuits 6a and 6b cancel each other out.</p> |
