| Abstract |
As one type of the interconnected device between HVDC systems, the DC/AC/DC converter is able toachieve high-voltage connection and bulk-power transportation, which makes this device fit theinterconnection of LCC-HVDCs. To achieve an efficient interconnected LCC-HVDC system, theDC/AC/DC converter is possible to operate under the condition that one LCC-HVDC runs at normaloperation and the other at the operation of power reversal. This requests the DC/AC/DC converter toregulate power in terms of the interconnection between positive voltage and the negative. Consideringthe economy of the interconnection, the DC/AC/DC converter uses half-bridge sub-modules, which isnot able to connect the negative-voltage system. To achieve the ability of negative-voltage connection,a switch yard is proposed to reverse the voltage polarity of DC/AC/DC converter. And a controlsystem of the DC/AC/DC converter is proposed to protect the normal LCC-HVDC from the influenceof LCC-HVDC during power reversal. |
