DEVICE FOR SWITCHING DIRECT CURRENTS

摘要

The invention relates to a device (1) for switching direct currents in a pole of a DC voltage network, comprising two connection terminals (21, 22), between which extends an operating current path (2) having a mechanical switch (4) that can be bridged by a shut-off branch (3); a power switching unit (5) which is disposed in the shut-off branch (3) and has a series circuit of two-pole submodules (10) having at least one power semiconductor switch (11) that can be switched on or off; and commutation means (6) for commutating the current from the operating current path (2) to the turn-off branch (3). The aim of the device is to reliably control fault currents in a DC voltage network, wherein at the same time low on-state losses are produced. In order to achieve said aim, the commutation means (6) are arranged in the shut-off branch (3) and are designed to produce a circuit current that flows through the bridged section of the operating current path (2) and the turn-off branch (3), said circuit current being opposite the current to be switched.