| 摘要 |
The invention relates to a converter arrangement (1, 101) comprising a first phase module extending between two d.c. voltage poles (51, 61) and having a first a.c. voltage connection (2), said first phase module comprising a first phase module branch (8) extending between the first a.c. voltage connection and the first d.c. voltage pole and a second phase module branch (9) extending between the first a.c. voltage connection and the second d.c. voltage pole. The converter arrangement also comprises a second phase module extending between the two d.c. voltage poles and having a second a.c. voltage connection (3), said second phase module correspondingly comprising a third and a fourth phase module branch (10, 11). Each of the phase module branches comprises a series connection of double-pole submodules (14) to at least one power semiconductor switch and an energy accumulator, which can in each case be bridged independently of the current direction by means of a bridging unit (33) arranged parallel to the connection terminals. The invention is characterised by a d.c. voltage switch (16) in one of the two d.c. voltage poles and an idle operation path (22), which extends between d.c. voltage connections which can be connected to the d.c. voltage connections and comprises a semiconductor element (23) having a blocking direction and a pass direction. The invention further relates to a method for short-circuit protection of the converter arrangement (1, 101). In the method according to the invention, in the event of a short-circuit on the d.c. voltage side, all submodules are bridged independently of the current direction, whereupon the d.c. voltage switch is switched off, such that a short-circuit current on the d.c. voltage side is commuted to idle operation. |
