| 摘要 |
Method and apparatus for controlling an apparatus transmitting power between two electricity networks or between an electricity network and a polyphase electric machine (M/G), which electricity networks can be polyphase alternating-current networks or one of them can be a single-phase direct-current network, and which apparatus comprises low-voltage power cells (C), which comprise a single-phase output connection (OUT). The power cells also comprise a single-phase input connector (IN), the power cells are arranged into groups (G 1 - G N , G P1 - G PN1 , G S1 - G SN2 , G 1 "'- G N "') such that at least one power cell per each phase of the electricity network or of the electric machine belongs to each group, and the input terminals (IN) of all the power cells belonging to the same group are connected to a common transformer, which transformer comprises its own separate winding that is galvanically isolated from the others for the power cell connected to it. The controllable power semiconductor switches connected to the input connectors (IN) of all the power cells supplying power to the same transformer are controlled essentially cophasally with a 50% pulse ratio. |
