PRESSURE COMPENSATED SUBSEA ELECTRICAL SYSTEM

• US 20170280577A1
• Filed: 08/10/2015
• Published: 09/28/2017
• Est. Priority Date: 08/22/2014
• Status: Active Grant

• Current Assignee: ABB Schweiz AG (ABB Limited)
• Original Assignee: ABB Schweiz AG (ABB Limited)
• Inventors: Laneryd, Tor, Gradinger, Thomas, Lendenmann, Heinz, Virtanen, Esa, Wagner, Thomas, Koivuluoma, Timo
• Granted Patent: US 10,244,650 B2
• Time in Patent Office: Days
• CPC Class Codes: F28D 1/022 for immersion in a natural body of water, e.g. marine radiators
• CPC Class Codes: H01F 27/14 Expansion chambers; Oil conservators; Gas cushions; Arrangements for purifying, drying, or filling
• CPC Class Codes: H02M 7/068 mounted on a transformer
• CPC Class Codes: H05K 5/068 having a pressure compensation device, e.g. membrane venting means H05K5/0213
• CPC Class Codes: H05K 7/20236 by immersion
• CPC Class Codes: H05K 7/209 Heat transfer by conduction from internal heat source to heat radiating structure H05K7/20909 takes precedence
• CPC Class Codes: H05K 7/20927 Liquid coolant without phase change

Abstract

A pressure compensated subsea electrical system and a pressure compensated subsea electrical system which has a housing filled with a dielectric liquid. The housing has a first housing portion and a second housing portion in pressure communication with each other. The first housing portion includes a transformer, and the second housing portion includes a power converter. The pressure compensated subsea electrical system includes a pressure compensator arranged to compensate pressure inside the housing. The pressure compensator is enabled to compensate pressure in both the first housing portion and the second housing portion.

Claims

1. A pressure compensated subsea electrical system, comprising:

a housing filled with a dielectric liquid, the housing having a first housing portion and a second housing portion in pressure communication with each other, the first housing portion comprising a transformer, and the second housing portion comprising a power converter;

a pressure compensator arranged to compensate pressure inside the housing, wherein the pressure compensator is enabled to compensate pressure in both the first housing portion and the second housing portion; and

a cooling circuit through which the dielectric liquid flows, the cooling circuit encompassing the power converter and the transformer.

2. The pressure compensated subsea electrical system according to claim 1, wherein the pressure communication is fluid communication.

3. The pressure compensated subsea electrical system according to claim 1, wherein the first housing portion comprises a tank wall for transferring heat from the power converter.

4. The pressure compensated subsea electrical system according to claim 1, wherein the housing further comprises:

at least one separating wall arranged between the power converter and the transformer.

5. The pressure compensated subsea electrical system according to claim 4, wherein the pressure communication consists of at least one through hole in the at least one separating wall.

7. The pressure compensated subsea electrical system according to claim 5, wherein at least one electrical connection runs through the at least one through hole in the at least one separating wall for electrically connecting the power converter and the transformer.

8. The pressure compensated subsea electrical system according to claim 3, wherein the tank wall comprises corrugations or cooling fins.

9. The pressure compensated subsea electrical system according to claim 1, wherein the power converter and the transformer are serially connected along the cooling circuit.

10. The pressure compensated subsea electrical system according to claim 9, wherein flow of the dielectric liquid inside the cooling circuit is driven at least partially by natural convection.

11. The pressure compensated subsea electrical system according to claim 9, wherein the transformer and the power converter are arranged relative the cooling circuit such that the flow of the dielectric liquid is induced by thermal losses in the transformer and is at least partially used to cool the power converter.

12. The pressure compensated subsea electrical system according to claim 1, wherein the transformer and the power converter are arranged such that in use the transformer is arranged in a vertical position above the power converter.

13. The pressure compensated subsea electrical system according to claim 1, further comprising:

a heat exchanger, the heat exchanger being provided on an outside wall of the housing.

14. The pressure compensated subsea electrical system according to claim 13, wherein the heat exchanger is arranged to receive dielectric liquid from the first housing portion and to provide dielectric liquid to the second housing portion.

15. The pressure compensated subsea electrical system according to claim 2, wherein the first housing portion comprises a tank wall for transferring heat from the power converter.

17. The pressure compensated subsea electrical system according to claim 10, wherein the transformer and the power converter are arranged relative the cooling circuit such that the flow of the dielectric liquid is induced by thermal losses in the transformer and is at least partially used to cool the power converter.

6. The pressure compensated subsea electrical system according to claim 6, wherein the at least one through hole has a total cross section of at least 1 square centimeter.

16. The pressure compensated subsea electrical system according to claim 6, wherein at least one electrical connection runs through the at least one through hole in the at least one separating wall for electrically connecting the power converter and the transformer.