| 摘要 |
This application relates to a voltage source converter (VSC) suitable for use, for example, for use in high voltage DC power distribution. The VSC has at least one phase limb (1 02a-c) having high side and low side converter arms. A converter arm comprises a first plurality of cells (103) for voltage wave-shaping, each cell comprising an energy storage element (105) such as a capacitor that can be selectively connected in series in the converter arm or bypassed. The converter arm also has a high voltage module (202; 501) connected in series with the first plurality of cells, the high voltage module comprising at least one energy storage element (206) such as a high voltage capacitor that can be selectively connected in series in the converter arm or bypassed. The voltage rating of the high voltage module (202, 501), i.e. the voltage stored in use, is greater than any of the cells (103) of the first plurality of cells. In use the high voltage module (202; 501) thus maintains a significantly greater voltage than any of the cells (103), for example at least half the magnitude of the voltage of a DC terminal of the converter and may be controlled by a controller (207) to provide voltage blocking support in an arm off state. |
