| 摘要 |
A converter arrangement (10b) comprises at least first and second modular multilevel converters (12a, 12b); wherein each of the at least first and second modular multilevel converters comprises at least two converter branches (16). Each converter branch (16) comprises a plurality of series-connected converter cells (20, 20'). Each converter cell comprises a cell capacitor (24) and semiconductor switches (22) for connecting and disconnecting the cell capacitor to the converter branch (16). At least two converter branches (16) of the first modular multilevel converter (12a) are connected via a first branch connection point (18) and at least two converter branches (16) of the second modular multilevel converter (12b) are connected via a second branch connection point (18). The at least first and second multilevel converters (12a, 12b) are connected in parallel via a phase connection point (40) for connecting the converter arrangement to a load (34, 36) or a power source (30, 32), wherein the phase connection point (40) is connected via a first inductance (38) with the first branch connection point (18) and/or via a second inductance (38) with the second branch connection point (18). At least one of the first and second modular multilevel converters (12a, 12b) may comprise a protection system (44, 46), which comprises: a fault detection device (48); a switch (50) for interconnecting at least two phases at the branch connection point (40) of the associated modular multilevel converter (12a, 12b); and a controller (52) adapted for switching converter cells (20, 20') of the associated modular multilevel converter (12a, 12b) to zero output voltage and for closing the switch (50), when receiving a fault signal from the fault detection device (48). |
