Subsea fuse assembly

Patent metadata

Field	Value
Publication number	US-12080503-B2
Application number	US-201917296270-A
Country	US
Kind code	B2
Filing date	Nov 25, 2019
Priority date	Nov 27, 2018
Publication date	Sep 3, 2024
Grant date	Sep 3, 2024

Abstract

The subsea fuse assembly includes an enclosure filled with a dielectric fluid and provided with an equalization opening, which is sealed with a flexible element. A first electric conductor extends into the enclosure through a first lead-through positioned in a wall of the enclosure. A second electric conductor is attached to an inner surface of a wall of the enclosure. A fuse is connected between the first electric conductor and the second electric conductor within the enclosure. A third electric conductor extends outside the enclosure and is attached to an outer surface of a wall of the enclosure. An electrically conductive path is thus provided between the second electric conductor and the third electric conductor through the electrically conductive enclosure.

First claim

The invention claimed is:

1. A subsea fuse assembly comprising:
an enclosure filled with a dielectric fluid and provided with an equalization opening in a wall of the enclosure, the enclosure being of an electrically conductive material,
a flexible element sealing the equalization opening in a fluid tight manner,
an electric insulation layer that comprises crepe paper and that is wrapped around the enclosure,
a first electric conductor extending into the enclosure through a lead-through positioned in a first wall of the enclosure,
a second electric conductor extending within the enclosure, wherein the second electric conductor is welded to an inner surface of a second wall of the enclosure that is different from the first wall of the enclosure,
a fuse connected between the first electric conductor and the second electric conductor within the enclosure,
a third electric conductor extending outside the enclosure and welded to an outer surface of the second wall of the enclosure,

wherein an electrically conductive path is provided between the first electric conductor and the third electric conductor via a serial connection of the enclosure, the second electric conductor and the fuse,
wherein the first wall comprises a back wall of the enclosure and the second wall comprises a front wall of the enclosure,
wherein the second electric conductor and the third electric conductor are conductively attached to the front wall and the first electric conductor passes through the back wall, and wherein the wall through which the first electric conductor passes in the enclosure is opposite to the wall on which the third electric conductor is attached.

2. The subsea fuse assembly according to claim 1 , wherein the first wall through which the first electric conductor passes in the enclosure is opposite to the second wall on which the second electric conductor is attached.

3. The subsea fuse assembly according to claim 1 , wherein the flexible element is a membrane.

4. The subsea fuse assembly according to claim 3 , wherein the membrane is selected from the group comprising a rubber membrane, a nitrile rubber membrane, a thermoplastic polyurethane membrane, a membrane comprising polyester filaments, a membrane comprising polyvinyl chloride, and a butyl rubber membrane.

5. A subsea installation comprising:
a pressure compensated main tank filled with a dielectric fluid,
an electric component submerged in the dielectric fluid in the main tank,
a subsea fuse assembly according to claim 1 , the subsea fuse assembly being submerged in the dielectric fluid in the main tank.

6. The subsea fuse assembly according to claim 1 , wherein the first wall is opposite the second wall.

7. The subsea fuse assembly according to claim 1 , wherein the enclosure comprises a bottom wall that contacts a first side of a pressure compensator.

8. The subsea fuse assembly according to claim 1 , wherein the enclosure comprises a mating flange that contacts a second side of the pressure compensator, and
wherein the second side of the pressure compensator is opposite the first side of the pressure compensator.

9. The subsea fuse assembly according to claim 1 , wherein the enclosure comprises a top wall that extends from the front wall to the back wall.

10. A subsea fuse assembly comprising:
an electrically conductive enclosure filled with a dielectric fluid and including a bottom wall, a front wall, a back wall that is opposite the front wall, at least one sidewall, and a bottom wall that is opposite the top wall comprises an equalization opening that forms a passage through the bottom wall;
a mating flange that is positioned against a bottom surface of the bottom wall and that is of a same size as bottom wall;
a pressure compensator is between the bottom wall and the mating flange and closes the equalization opening to form a fluid type seal;
a lead through that comprises plastic or resin and that is mounted in a lead through opening on the back wall to provide a fluid type seal;
a first electric conductor that is directed through the lead through into an interior of the electrically conductive enclosure;
a second electric conductor that is provided in the interior enclosure and comprising a first end being welded to an inner surface of the front wall of the enclosure;
a third electric conductor comprising a first end that is conductively connected to an outer surface of the front wall;
a fuse connected between the first electric conductor and the second end of the second electric conductor within the enclosure, wherein the fuse is serially connected to the second electric conductor which is serially connected to the third electric connector, wherein the fuse is mechanically supported by the first electric conductor and the second electric conductor; and
an electric insulation layer that comprises crepe paper and that is wrapped around the enclosure,
wherein the first electric conductor is routed from outside the enclosure to the interior of the enclosure and is electrically insulated from the enclosure via the lead through and the second electric conductor is conductively coupled to the enclosure and does not extend outside the interior, and wherein the third electric conductor is conductively coupled to the enclosure and does not extend to the interior of the enclosure.

Assignees

• Hitachi Energy Ltd

Inventors

• Launonen Markku

Classifications

• H01H85/1755

  composite casing · CPC title

• H01H85/055

  Fusible members · CPC title

• H01H85/175

  characterised by the casing shape or form · CPC title

• H01H85/17

  characterised by the casing material · CPC title

• H01H85/143

  Electrical contacts; Fastening fusible members to such contacts · CPC title