| 摘要 |
<p>An arrangement for exchanging power with a three-phase electric power network comprises a Voltage Source Converter (5) having three phase legs (A-C) with each a series connection of switching cells. The three phase legs are interconnected by forming a delta-connection. The arrangement also comprises a control unit (19) configured to calculate a value for amplitude and phase position for a zero-sequence current for which, when circulated in the delta-connection circuit of said three phase legs, the balance of the total direct voltage of each of said three phase legs (A-C) with respect to the other two phase legs is restored will there be an unbalance and control the semiconductor devices of switching cells of the phase legs to add such a zero-sequence current to the currents of each phase leg of the converter.</p> |
