DIRECT-CURRENT INTERRUPTION DEVICE

A DC breaker 1 includes a mechanical disconnection switch 2 provided at a power transmission line 100, a mechanical circuit breaker 20 connected in series to the mechanical disconnection switch 2, and a parallel circuit 3 connected in parallel with the mechanical disconnection switch 2 and the mechanical circuit breaker 20. The parallel circuit 3 includes a semiconductor circuit breaker 4 that changes a supply or a breaking of the current from the power transmission line 100 to the parallel circuit 3, and a reactor 55 connected in series to the semiconductor circuit breaker 4. An H-bridge circuit 5 which connects one point between the mechanical disconnection switch 2 and the mechanical circuit breaker 20 to one point between the semiconductor circuit breaker 4 and the reactor 55 is provided. The H-bridge circuit 5 includes an H-bridge unit 50 including a plurality of switching elements 51 and a capacitor 53. The H-bridge circuit 5 controls the current flowing through the mechanical circuit breaker 20 by an output voltage control.