DC energy store systems and methods of operating the same

Patent metadata

Field	Value
Publication number	US-9614400-B2
Application number	US-201113703472-A
Country	US
Kind code	B2
Filing date	Jun 8, 2011
Priority date	Jun 14, 2010
Publication date	Apr 4, 2017
Grant date	Apr 4, 2017

Abstract

A dc energy store system includes a dc energy store, an AC/DC power converter having ac terminals connected to an ac power supply and dc terminals connected to the dc energy store, and at least one auxiliary unit associated with the dc energy store. The dc energy store system is adapted to be operated in a number of different operating modes including: (i) a first mode to supply power from the ac power supply to the dc energy store; (ii) a second mode to supply power from the dc energy store to the ac power supply; (iii) a third mode to supply power from the ac power supply to the auxiliary unit(s); and (iv) a fault mode where there is a fault in the ac power supply, and power is supplied from the dc energy store to the auxiliary unit(s).

First claim

What is claimed is:

1. A method of operating a dc energy store system comprising a dc energy store, an AC/DC power converter having ac terminals connected to an ac power supply and dc terminals connected to the dc energy store, and at least one auxiliary unit associated with the dc energy store, the method comprising the steps of:
(i) in a first mode supplying power from the ac power supply to the dc energy store wherein the power is stored therein;
(ii) in a second mode supplying power from the dc energy store to the ac power supply, wherein the DC energy store supplies bi-directional power flow between the AC power supply and the DC energy store depending on whether energy is being stored in the DC energy store or returned to the ac power supply;
(iii) in a third mode supplying power from the ac power supply to the at least one auxiliary unit associated with the dc energy store; and
(iv) in the event of a fault in the ac power supply receiving power from an external power source, supplying the power stored from the dc energy store to the at least one auxiliary unit associated with the dc energy store and from the dc energy store back to the ac power supply, until the power stored in the dc energy store is exhausted.

2. A dc energy store system comprising:
a dc energy store;
an AC/DC power converter having ac terminals connected to an ac power supply and dc terminals connected to the dc energy store; and
at least one auxiliary unit associated with the dc energy store;
wherein the dc energy store system is adapted to be operated:
(i) in a first mode to supply power from the ac power supply to the dc energy store, wherein the power is stored therein;
(ii) in a second mode to supply power from the dc energy store to ac power supply, wherein the DC energy store supplies bi-directional power flow between the AC power supply and the DC energy store depending on whether energy is being stored in the DC energy store or returned to the ac power supply;
(iii) in a third mode to supply power from the ac power supply to the at least one auxiliary unit associated with the dc energy store; and
(iv) in the event of a fault in the ac power supply from an external power source, to supply the power stored from the dc energy store to the at least one auxiliary unit associated with the dc energy store and from the dc energy store back to the ac power supply until the power stored at the dc energy store is exhausted.

3. The dc energy store system of claim 2 , wherein the ac terminals of the AC/DC power converter are connected to the ac power supply by means of a switched connection.

4. The dc energy store system of claim 3 , wherein the switched connection includes a first switch and a second switch.

5. The dc energy store system of claim 4 , wherein the at least one auxiliary unit is connected to the switched connection at a first junction between the first and second switches.

6. The dc energy store system of claim 5 , wherein the at least one auxiliary unit is connected to the first junction of the switched connection by a third switch.

7. The dc energy store system of claim 6 , wherein the at least one auxiliary unit is further connected to the switched connection at a second junction between the second switch and the ac terminals of the AC/DC by a fourth switch.

8. The dc energy store system of claim 6 , wherein the at least one auxiliary unit is further connected to the dc terminals of the AC/DC power converter by a DC/AC power convener and a fifth switch.

9. The dc energy store system of claim 5 , wherein the switched connection further includes a harmonic filter connected between the second switch and the ac terminals of the AC/DC power converter.

10. The dc energy store system of claim 5 , wherein the switched connection further includes a transformer connected between the first switch and the first junction.

11. The dc energy store system of claim 2 , further comprising a DC/DC power converter having a first pair of dc terminals connected to the dc terminals of the AC/DC power converter and a second pair of dc terminals connected to the dc energy store.

12. The dc energy store system of claim 11 , further comprising a dc link between the second pair of dc terminals of the DC/DC power converter and the dc energy store, the dc link including a sixth switch.

13. The dc energy store system of claim 5 , further comprising a DC/DC power converter having a first pair of dc terminals connected to the dc terminals of the AC/DC power converter by means of a dc link and a second pair of dc terminals connected to the dc energy store, wherein the at least one auxiliary unit is further connected to the dc link by a DC/AC power converter and a fifth switch.

14. The dc energy store system of claim 6 , further comprising a DC/DC power converter having a first pair of dc terminals connected to the dc terminals of the AC/DC power converter by means of a dc link and a second pair of dc terminals connected to the dc energy store, wherein the at least one auxiliary unit is further connected to the dc link by a DC/AC power converter and a fifth switch.

15. The dc energy store system of claim 2 , wherein the at least one auxiliary unit is a pump, a fan, an uninterruptible power supply (UPS), control unit or other device.

16. The dc energy store system of claim 2 , further comprising a first auxiliary unit being an uninterruptible power supply (UPS) and a second auxiliary unit being a pump or a fan associated with the dc energy store.

17. The dc energy store system of claim 16 , further comprising a control unit for controlling the operation of the AC/DC power converter, the control unit being connected to the first auxiliary unit.

18. The dc energy store system of claim 2 , wherein ac power is supplied from the ac power supply to the at least one auxiliary unit in the third mode, at the same time as power is being supplied from the ac power supply to the dc energy store in the first mode or from the dc energy store to the ac power supply in the second mode.

Assignees

• Lewis Eric Anthony
• Ge Energy Power Conversion Technology Ltd

Inventors

• Lewis Eric Anthony

Classifications

• H02J9/04 Primary

  in which the distribution system is disconnected from the normal source and connected to a standby source · CPC title

• H02J9/062 Primary

  for AC powered loads · CPC title

• H02M7/66

  with possibility of reversal · CPC title

• Y10T307/344

  Cross-Sectional Technologies · mapped topic

• H02J9/06 Primary

  with automatic change-over {, e.g. UPS systems} · CPC title