CONTROL OF DC VOLTAGE DISTRIBUTION SYSTEM

• US 20200136423A1
• Filed: 10/25/2019
• Published: 04/30/2020
• Est. Priority Date: 10/29/2018
• Status: Active Grant

• Current Assignee: ABB Schweiz AG (ABB Limited)
• Original Assignee: ABB Schweiz AG (ABB Limited)
• Inventors: Haxhiu, Arber, Kanerva, Sami, Chan, Ricky Riyadi
• Granted Patent: US 11,601,006 B2
• Time in Patent Office: Days
• CPC Class Codes: H01M 16/003 of fuel cells with other electrochemical devices, e.g. capacitors, electrolysers
• CPC Class Codes: H01M 16/006 of fuel cells with rechargeable batteries
• CPC Class Codes: H01M 8/04873 of the individual fuel cell
• CPC Class Codes: H01M 8/04888 of auxiliary devices, e.g. batteries, capacitors
• CPC Class Codes: H01M 8/04932 of the individual fuel cell
• CPC Class Codes: H01M 8/04947 of auxiliary devices, e.g. batteries, capacitors
• CPC Class Codes: H02J 1/08 Three-wire systems; Systems having more than three wires
• CPC Class Codes: H02J 1/10 Parallel operation of dc sources
• CPC Class Codes: H02J 1/102 being switching converters H02J1/108, H02J1/12 take precedence
• CPC Class Codes: H02J 2300/30 The power source being a fuel cell
• CPC Class Codes: H02J 2310/42 for ships or vessels
• CPC Class Codes: H02J 7/34 Parallel operation in networks using both storage and other dc sources, e.g. providing buffering H02J7/14 takes precedence
• CPC Class Codes: H02M 3/158 including plural semiconductor devices as final control devices for a single load
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02E 60/50 Fuel cells

Abstract

A DC voltage distribution arrangement and method of controlling a DC voltage distribution system, the DC voltage distribution system including a DC voltage bus, a fuel cell electrically connected to the DC voltage bus, an energy storage and an energy storage converter, wherein the input of the energy storage converter is connected to the energy storage and the output of the energy storage converter is connected to the DC bus. The method comprises providing a DC voltage reference for the energy storage converter, the energy storage converter controlling the voltage of the DC voltage bus by providing power from the energy storage or to the energy storage, detecting power flow of the energy storage converter, and changing the DC voltage reference on the basis of the detected power flow to change the power taken from the fuel cell.

Claims

1. A method of controlling a DC voltage distribution system, the DC voltage distribution system comprising

a DC voltage bus,

a fuel cell electrically connected to the DC voltage bus,

an energy storage and an energy storage converter, wherein the input of the energy storage converter is connected to the energy storage and the output of the energy storage converter is connected to the DC bus,

wherein the method comprises

providing a DC voltage reference for the energy storage converter, the energy storage converter controlling the voltage of the DC voltage bus by providing power from the energy storage or to the energy storage,

detecting power flow of the energy storage converter, and

changing the DC voltage reference on the basis of the detected power flow to change the power taken from the fuel cell.

2. The method according to claim 1, wherein the DC voltage reference is further changed to charge the energy storage.

3. The method according to claim 1, wherein the DC voltage distribution system comprises a fuel cell converter, wherein the input of the fuel cell converter is connected to the fuel cell and the output of the fuel cell converter is connected to the DC voltage bus.

4. The method according to claim 3, wherein the fuel cell converter is operated to convert the fuel cell voltage to a lower value when the voltage of the fuel cell is above an upper limit set for the DC voltage of the DC voltage bus.

5. The method according to claim 3, wherein the fuel cell converter is operated to convert the fuel cell voltage to a higher value when the voltage of the fuel cell is below a lower limit set for the DC voltage of the DC voltage bus.

6. The method according to claim 1, wherein the DC voltage reference is increased when the detected power flow is towards the energy storage.

7. The method according to claim 1, wherein the DC voltage reference is decreased when the detected power flow is from the energy storage.

9. The method according to claim 2, wherein the DC voltage distribution system comprises a fuel cell converter, wherein the input of the fuel cell converter is connected to the fuel cell and the output of the fuel cell converter is connected to the DC voltage bus.

10. The method according to claim 9, wherein the fuel cell converter is operated to convert the fuel cell voltage to a lower value when the voltage of the fuel cell is above an upper limit set for the DC voltage of the DC voltage bus.

11. The method according to claim 4, wherein the fuel cell converter is operated to convert the fuel cell voltage to a higher value when the voltage of the fuel cell is below a lower limit set for the DC voltage of the DC voltage bus.

12. The method according to claim 2, wherein the DC voltage reference is increased when the detected power flow is towards the energy storage.

13. The method according to claim 3, wherein the DC voltage reference is increased when the detected power flow is towards the energy storage.

14. The method according to claim 4, wherein the DC voltage reference is increased when the detected power flow is towards the energy storage.

15. The method according to claim 2, wherein the DC voltage reference is decreased when the detected power flow is from the energy storage.

16. The method according to claim 3, wherein the DC voltage reference is decreased when the detected power flow is from the energy storage.

17. The method according to claim 4, wherein the DC voltage reference is decreased when the detected power flow is from the energy storage.

18. The method according to claim 5, wherein the DC voltage reference is decreased when the detected power flow is from the energy storage.

19. The method according to claim 9, wherein the DC voltage reference is decreased when the detected power flow is from the energy storage.

20. The method according to claim 9, wherein the DC voltage reference is increased when the detected power flow is towards the energy storage.

8. A DC voltage distribution arrangement, the DC voltage distribution arrangement comprising

a DC voltage bus,

a fuel cell electrically connected to the DC voltage bus,

an energy storage and an energy storage converter, wherein the input of the energy storage converter is connected to the energy storage and the output of the energy storage converter is connected to the DC bus,

means for providing a DC voltage reference for the energy storage converter, the energy storage converter controlling the voltage of the DC voltage bus by providing power from the energy storage or to the energy storage,

means for detecting power flow of the energy storage converter, and

means for changing the DC voltage reference on the basis of the detected power flow to change the power taken from the fuel cell.