Statcom System For Providing Reactive And/Or Active Power To A Power Network

• US 20100171472A1
• Filed: 03/12/2010
• Published: 07/08/2010
• Est. Priority Date: 09/14/2007
• Status: Active Grant

• Current Assignee: Hitachi Energy Limited (Hitachi, Ltd.)
• Original Assignee: ABB Technology AG (ABB Limited)
• Inventors: Angquist, Lennart
• Granted Patent: US 8,154,896 B2
• Time in Patent Office: Days
• US Class Current: 323/207
• CPC Class Codes: H02J 3/1842 wherein at least one reactive element is actively controlled by a bridge converter, e.g. active filters
• CPC Class Codes: Y02E 40/10 Flexible AC transmission systems [FACTS]
• CPC Class Codes: Y02E 40/20 Active power filtering [APF]

Abstract

A static compensator system for providing reactive and/or active power to a power network. The system includes a static compensator, which has a DC capacitor U_d and a voltage source converter. The static compensator is connected to an energy storage device. The system further includes a booster converter device connected in series with the energy storage device and in parallel with the DC capacitor U_d of the static compensator. The booster converter device and the energy storage device are further connected in parallel with the voltage source converter of the static compensator.

Claims

1. A static compensator system for providing reactive and/or active power to a power network, said system comprising a static compensator comprising a DC capacitor and a voltage source converter connected in parallel, said static compensator being connected to an energy storage device, characterized by a booster converter device connected in series with said energy storage device, wherein said booster converter device and said energy storage device are connected in parallel with said DC capacitor of said static compensator, and wherein said booster converter device and said energy storage device are connected in parallel with said voltage source converter of said static compensator.

2. The static compensator system as claimed in claim 1, wherein said booster converter device is connected to a transformer in turn connected to AC terminals of said static compensator, whereby said booster converter device is arranged to be energized from AC terminals of said static compensator.

3. The static compensator system as claimed in claim 2, wherein said static compensator further comprises a transformer, and wherein said transformer connected to said booster converter device is connected to the AC terminals of said static compensator via said transformer of said static compensator.

4. The static compensator system as claimed in claim 1, wherein said booster converter device comprises a current source converter.

5. The static compensator system as claimed in claim 4, wherein said current source converter comprises thyristor valves.

6. The static compensator system as claimed in claim 1, wherein said booster converter device is arranged to handle a voltage difference between said energy storage device and said DC source.

7. The static compensator system as claimed in claim 1, wherein said booster converter device is arranged to charge said energy storage device.

8. The static compensator system as claimed in claim 1, wherein said booster converter device comprises means for producing unidirectional voltage.

9. The static compensator system as claimed in claim 1, wherein said booster converter device comprises means for producing bidirectional voltage.

10. The static compensator system as claimed in claim 1, wherein said DC capacitor of said static compensator is arranged to maintain a constant DC voltage to said voltage source converter of said static compensator.

11. The static compensator system as claimed in claim 1, wherein said booster converter device is arranged to be fed by means of a separate AC feed.

12. The static compensator system as claimed in claim 1, wherein said energy storage device comprises a DC capacitor, a super capacitor, an electrochemical battery, a fuel cell or photovoltaric modules.

13. The static compensator system as claimed in claim 1, wherein said booster converter device comprises means for producing reactive power to said network.

14. The static compensator as claimed in claim 13, wherein said means for producing reactive power comprises turn-off semiconductor devices, such as gate turn-off thyristors.