WO2017017317A1

WO2017017317A1 - Electrical apparatus designed to be submerged, and electrical system comprising such an apparatus

Info

Publication number: WO2017017317A1
Application number: PCT/FR2015/052097
Authority: WO
Inventors: Edouard THIBAUT; Bruno LEFORGEAIS
Original assignee: Total Sa
Priority date: 2015-07-28
Filing date: 2015-07-28
Publication date: 2017-02-02
Also published as: AR105511A1

Abstract

The invention relates to an electrical apparatus (14) designed to be submerged, particularly at a great depth, typically one or several hundred metres, said apparatus comprising a sealed housing (30) and at least one electrical module (32) arranged inside the housing (30). The electrical apparatus (14) also comprises: at least one conduit (36) through which an electric cable (16) is guided, each cable conduit (36) passing through the housing (30); and at least one current transformer (38), each current transformer (38) being arranged around a respective cable conduit (36) and being designed to power the at least one electrical module (32) arranged inside the housing (30) by means of a current circulating in the corresponding electric cable (16).

Description

Electrical equipment, intended to be immersed, and electrical system comprising such equipment

The present invention relates to an electrical equipment, intended to be immersed, particularly at great depth, typically at one or several hundred meters, the electrical equipment comprising a sealed housing and at least one electrical module disposed inside the housing.

The invention also relates to an electrical system, intended to be immersed and comprising at least one such electrical equipment and at least one electrical cable.

The invention generally relates to the power supply of submerged underwater electrical equipment, particularly at great depth, typically several hundred meters, or even several thousand meters deep. In this area, the environment is particularly restrictive, particularly due to the hydrostatic pressure associated with the depth. The required reliability is also high, the required lifetime being generally greater than 20 years.

Document WO 201/1/029566 A1 discloses an electrical system of the aforementioned type. The electrical system is a subsea submerged electrical system, and includes a number of subsea electrical equipment that is connected, via electrical cables, to a power source, for example a power converter, the source feeding being preferably underwater. The electrical connections between, on the one hand, the cables, and on the other hand, the electrical equipment or the power supply, are connections with a wet mateable connection, or connections with dry mateable connection where necessary the use of penetrators with wall penetrations.

WO 2015/004000 A1 discloses a similar underwater electrical system with subsea electrical equipment connected to an underwater power source, such as an underwater power converter, preferably via connections with coupling in a humid environment, or connections with coupling in a dry environment which, however, have less reliability and a higher cost.

However, such electrical systems with these many electrical connections are relatively expensive regardless of the type of connections, that is to say with coupling in a wet or dry environment, and may also have a relatively low reliability. The object of the invention is therefore to provide electrical equipment to reduce costs, while maintaining reliability or improving.

To this end, the invention relates to an electrical equipment of the aforementioned type, wherein the electrical equipment further comprises:

at least one passage duct for an electric cable, each passage duct passing through the casing,

- At least one current transformer, each current transformer being arranged around a respective passage duct and being configured to supply, from a current flowing in the corresponding electric cable, the electrical module or modules arranged at the inside the case.

The electrical equipment according to the invention does not then require an electrical connector to receive a power supply from the corresponding electrical cable, the coupling between the electrical module or modules to be powered and said electrical cable being an inductive coupling. This lack of electrical connector for electrical equipment therefore, at the same time, to reduce costs and improve reliability.

According to other advantageous aspects of the invention, the electrical equipment comprises one or more of the following characteristics, taken separately or in any technically possible combination:

the electrical equipment comprises several electrical cable ducts and several current transformers;

each current transformer is in the shape of a torus;

- Each current transformer comprises at least one turn disposed at least partially around the corresponding passage conduit;

each turn is disposed over the entire periphery of the corresponding passage duct;

at least one passage duct has a diameter of variable value and each turn disposed around said passage duct has a diameter of variable value;

- The or turns of the current transformer are molded in a sealed chamber disposed inside the housing and around the corresponding passage conduit; and

each turn is of circular or rectangular shape.

The subject of the invention is also an electrical system intended to be immersed, particularly at great depth, typically several hundred meters away, the electrical system comprising at least one electrical equipment and at least one electrical cable, in which each electrical equipment is as defined above, and each electrical cable is disposed inside a passage duct for at least one corresponding electrical equipment.

According to other advantageous aspects of the invention, the electrical system comprises one or more of the following characteristics, taken separately or in any technically possible combination:

each electrical cable has two ends intended to be connected to a power source, and each electrical cable is provided, at at least one of its ends, with a connector that can be coupled in a humid medium with a complementary connector. equipping the power source;

each electrical cable is provided, at one of its ends, with an indenter for an electrical coupling in a dry medium with a complementary connector inside the power source;

- At least one electrical cable is provided at each of its ends, a connector adapted to be coupled in a humid environment with a complementary connector equipping the power source;

- The electrical system further comprises a power source, connected to each electrical equipment via the electrical cable or cables; and

each electrical cable comprises a single electrical conductor. These features and advantages of the invention will become apparent on reading the description which follows, given solely by way of nonlimiting example, and with reference to the appended drawings, in which:

- Figure 1 is a schematic representation of an electrical system comprising three electrical equipment and a power source, according to a first embodiment of the invention;

FIG. 2 is a view similar to that of FIG. 1, according to a second embodiment of the invention; and

- Figure 3 is a view similar to that of Figure 1, according to a third embodiment of the invention.

In Figure 1, an electrical system 10 comprises a power source 12, at least one electrical equipment 14 and at least one electrical cable 16 connecting the power supply 12 to one or more electrical equipment 14 corresponding. In the example of Figure 1, the electrical system 10 comprises three electrical equipment 14 and a single electrical cable 16 connecting the power source 12 to three electrical equipment 14, arranged in series one after the other.

The electrical system 10 is intended to be immersed, especially at great depth, typically several hundred meters. The electrical system 10 is then also called subsea electrical system.

In a variant not shown, the electrical system 10 comprises at least two electrical cables 16, each electrical cable 16 connecting the power source 12 to one or more electrical equipment 14 separate from one cable to another.

The power source 12 is preferably a power source intended to be immersed, especially at great depth, typically several hundred meters, and is then also called underwater power source.

The power source 12 is known per se, and is capable of delivering, on an internal bus 17, a single-phase or polyphase alternating current.

The power source 12 is, for example, an alternating energy converter into another alternative energy, connected to an alternating network, not shown. As a variant, the power source 12 is, for example, a continuous energy converter for alternating energy, such as an inverter, connected to a continuous network.

In the example of FIG. 1, the power supply 12 comprises a through-passage of walls 18 at a first end 20 of the electric cable and a connector 22 for wet-coupling (English wet mateable connector) intended to be coupled into the water with a complementary connector 24 fitted to the other end 26 of the cable, also called the second end 26.

Each electrical equipment 14 is intended to be immersed, especially at great depth, typically one or several hundred meters deep, and is also called electrical equipment underwater.

Each electrical equipment 14 comprises a sealed housing 30 forming the outer casing of the electrical equipment and intended to be in contact with the water when the electrical equipment is immersed.

Each electrical equipment 14 also comprises at least one electrical module 32 disposed inside the housing 30. In the example of FIG. 1, the different electrical equipment items 14 each comprise two electrical modules 32, each module 32 being connected in series with an internal power bus 34.

According to the invention, each electrical equipment 14 further comprises at least one conduit 36 configured to allow the passage of an electrical cable, such as cable 16, each passage conduit 36 passing through the housing 30. Each passage conduit 36 through the sealed housing 30 from one side, while maintaining the sealing of the housing 30. In other words, the inside of each passage conduit 36 is intended to be in contact with the water when the electrical equipment 14 is immersed, while not allowing the water to enter the interior of the housing 30. In other words, each passage duct 36 forms an orifice passing through the housing 30 and opening through said housing without communicating with the interior of the housing 30.

According to the invention, each electrical equipment 14 also comprises at least one current transformer 38, each current transformer 38 being arranged around a respective passage duct 36, while being inside the sealed housing 30. Each transformer current 38 is configured to supply, from a current flowing in the corresponding electrical cable 16, the electrical module or modules 32 disposed inside the housing 30. In other words, each current transformer 38 is arranged around an outer surface of the passage duct 36 while being inside the casing 30, and the electric cable 16 is disposed inside the passage duct 36, that is to say facing an inner surface of this conduit, this for each electrical equipment 14 powered by said electric cable.

Each electrical cable 16 preferably comprises a single electrical conductor 40, as shown in FIG. Each electrical cable 16 comprises an outer envelope 41 surrounding the electrical conductor 40 and protecting it from the external environment, the outer envelope 41 being intended to be in contact with the water when the electric cable 16 is immersed.

Each electrical cable 16 is disposed inside a corresponding passage duct 36 for each electrical equipment 14 intended to be supplied by means of this cable, and then has an external diameter of value less than the internal diameter of the duct. passage 36 corresponding.

Each electrical cable 16 has its two ends 20, 26 intended to be connected to the supply source 12. Each electrical cable 16 is provided, at at least one of its ends, with the connector 24 which can be coupled in the middle. wet with the complementary connector 22 fitted to the power source 12.

According to the first embodiment of the invention, each electrical cable 16 cooperates, in the other of its ends, namely the first end 20 in the example of Figure 1, with the indenter 18 for an electrical coupling in medium dry (English dry mateable οοηηβοίοή with a complementary connector, not shown, inside the power source 12. Those skilled in the art will observe that the electrical conductor 16 is not necessarily centered with respect to the passage duct 36 or with respect to the current transformer 38, the inductive coupling only requiring the electrical cable 16 to pass through the transformer current 38.

The sealed housing 30 is known per se, and is adapted to withstand the hydrostatic pressure corresponding to the depth at which the electrical equipment 14 is intended to be immersed.

Each electrical module 32 is known per se. The electrical module 32 is for example a control module of one or more subsea electronic devices external to the equipment 14, also called SCM (English Subsea Control Modulated). Alternatively or additionally, the electrical module 32 is a power supply module configured to electrically power auxiliary elements, such as sensors (s) and / or actuators (s).

The internal supply bus 34 is for example a DC bus fed directly via the current transformer 38, the current transformer 38 being adapted to receive an induced current, from the current flowing in the electrical cable 16 therethrough.

Each passage duct 36 is for example formed of a wall sealingly attached to the housing 30, and the inner surface of this wall is intended to be facing the electrical cable 16, while the outer surface of this wall is intended to be opposite the current transformer 38. In other words, the electrical cable 16 and the current transformer 38 are arranged on either side of the passage duct 36, thus allowing simple supply of the electrical equipment 14 via the cable. 16, while avoiding water infiltration inside the electrical equipment 14.

The passage duct 36 is, for example, in the form of a rigid wall. As a variant, for a compensated pressure equipment item 14, the passage duct 36 is in the form of a flexible wall, and the passage duct 36 then has a diameter of variable value.

Each current transformer 38 is, for example, in the form of a torus, as shown in FIG.

Each current transformer 38 comprises at least one turn 42 arranged at least partially around the corresponding passage duct 36. In the example of FIG. 1, each current transformer 38 comprises a plurality of turns 42 arranged around the passage duct 36.

In addition optional, the electrical conductor 40 is a conductor adapted to carry both a power supply and data. Each turn 42 is preferably disposed over the entire outer periphery of the passage conduit 36 corresponding. When the current transformer 38 has several turns 42, they are connected to each other and then form a winding around the corresponding passage duct 36. The winding has for example a helical shape.

Each turn 42 has a larger diameter than the outer diameter of the passage duct 36, in order to be arranged around it. The diameter value of each coil 42 is for example fixed. Alternatively, for a compensated pressure equipment 14, the diameter value of each turn 42 is variable.

The fact of having a variable turn diameter then makes it possible to provide a maximum diameter to facilitate insertion of the electrical cable 16 inside the passage duct 36 when it preferably also has a diameter of variable value, then to reduce the value of the diameter of the passage duct, and also that of the diameter of each coil 42. This then makes it possible to reduce the distance between the electric cable 16 and the corresponding coil or turns 42, to optimize the power transfer by inductive coupling between the electrical cable 16 and the or turns 42 of the current transformer.

The inside diameter of each turn 42 is of course greater than the outside diameter of the electric cable 16, while being preferably less than or equal to twice the value of said outer diameter of the electric cable 16.

The or turns 42 of the current transformer are, for example, molded in a sealed chamber 44, disposed inside the housing 30 and around the corresponding conduit 36, as shown in FIG.

Each turn 42 is for example circular or rectangular, as known per se.

Thus, the electrical equipment 14 according to the invention is then configured to be fed reliably and simply by the electric cable 16, without requiring a connection with wet coupling with said cable, or a wall penetration, which reduces costs while improving reliability. In other words, the electrical equipment 14 according to the invention does not need to be provided with a specific electrical connector to receive a power supply from the corresponding electrical cable 16, the coupling between the electrical module or modules 32 and the electrical cable 16 being an inductive coupling via the current transformer 38. This lack of electrical connector for the electrical equipment 14 then allows to improve the tightness of the equipment, by limiting the risks of water infiltration inside the case, while reducing costs.

FIG. 2 illustrates a second embodiment of the invention, for which the elements identical to the first embodiment, previously described with reference to FIG. 1, are marked with identical references, and are not described again.

According to this second embodiment, at least one electric cable 16 is provided, at each of its ends 20, 26, with a connector that can be coupled in a humid medium with a complementary connector fitted to the power source 12.

In the example of FIG. 2, the electric cable 16 further comprises, at its second end 26, in a similar manner to the first embodiment, the connector 24 adapted to be coupled in a humid medium with the complementary connector 22 equipping the source of power. 12.

According to the second embodiment, the electric cable 16 also then comprises at its first end another connector 100 capable of being coupled in a humid medium with a complementary connector 102 fitted to the power source 12.

This then makes it possible to facilitate the installation of the electrical system 10, the electrical cable 16 being disconnectable from the supply source 12 at each of its ends 20, 26. In comparison, with the electrical system 10 according to the first embodiment, the electric cable 16 is easily disconnectable only at its second end 26 which is the only end provided with a coupling connector in a humid environment.

The operation of the electrical system 10 according to this second embodiment is also similar to that of the electrical system according to the first embodiment, described above, and is not described further.

The other advantages of this second embodiment are similar to those of the first embodiment, described above, and are not described again. FIG. 3 illustrates a third embodiment of the invention for which the elements identical to the first embodiment, previously described with reference to FIG. 1, are identified by identical references, and are not described again.

According to this third embodiment, the electrical system 10 comprises several electrical cables 16 connected to the power source 12, the electrical conductors 40 of the cables then being connected to a polyphase supply bus 200 disposed inside the source 12 power supply. In the example of Figure 3, the electrical system 10 comprises three electrical cables 16, and the three electrical conductors 40 are then connected to the internal bus 200 which is a three-phase bus.

According to this third embodiment, each electrical equipment 14 then comprises several passage ducts 36 and several current transformers 38, in order to be able to be supplied simultaneously by the different electric cables 16.

In the example of FIG. 3, each electrical equipment item 14 comprises three passage ducts 36 and three current transformers 38, each current transformer 38 being disposed around a respective passage duct 36 and being configured to supply the one or more electrical modules (not shown for the sake of simplification of the drawing) arranged inside the housing 30, from the different currents flowing in the electric cables 16.

Those skilled in the art will of course understand that the number of passage ducts 36 is likely to vary from electrical equipment 14 to the other, and that the number of current transformers 38 is preferably equal to the number of ducts passing through. 36 for a given electrical equipment 14, each current transformer 38 then being arranged around a respective passage duct 36.

The fact that one or more electrical equipment 14 comprises (s) several passage ducts 36 and several current transformers 38 makes it possible to supply the corresponding electrical equipment (s) 14 by means of several electric cables 16 arranged in parallel.

The operation of the electrical system 10 according to this third embodiment is also identical to that of the electrical system according to the first embodiment, and is not described again.

The other advantages of this third embodiment are similar to those of the first embodiment, described above, and are not described again.

It is thus conceived that the electrical equipment 10 according to the invention makes it possible to reduce costs, while offering better reliability.

Claims

1 .- Electrical equipment (14), intended to be immersed, especially at great depth, typically at one or several hundred meters, the electrical equipment (14) comprising a sealed housing (30) and at least one electrical module (32). ) disposed within the housing (30),

characterized in that the electrical equipment (14) further comprises:

at least one duct (36) for the passage of an electric cable (16), each passage duct (36) passing through the casing (30),

at least one current transformer (38), each current transformer

(38) being arranged around a respective passage duct (36) and being configured to supply, from a current flowing in the corresponding electric cable (16), the electrical module or modules (32) arranged at the inside the housing (30).

The electrical equipment (14) of claim 1, wherein the electrical equipment (14) comprises a plurality of electrical cable conduits (36) (16) and a plurality of current transformers (38).

3. - Electrical equipment (14) according to claim 1 or 2, wherein each current transformer (38) is in the form of a torus.

4. - Electrical equipment (14) according to any one of the preceding claims, wherein each current transformer (38) comprises at least one turn (42) disposed at least partially around the corresponding conduit (36).

5. - Electrical equipment (14) according to claim 4, wherein each turn (42) is disposed over the entire periphery of the passage conduit (36) corresponding.

6. Electrical equipment (14) according to claim 4 or 5, wherein at least one passage duct (36) has a variable value diameter and each turn (42) disposed around said passage duct (36) has a diameter variable value.

7. Electrical equipment (14) according to any one of claims 4 to 6, wherein the or turns (42) of the current transformer (38) are molded in a sealed chamber disposed inside the housing (30) and around the corresponding conduit (36).

8. - Electrical equipment (14) according to any one of claims 4 to 7, wherein each turn (42) is circular or rectangular.

9. - Electrical system (10), intended to be immersed, especially at great depth, typically several hundred meters, the electrical system (10) comprising at least one electrical equipment (14) and at least one electrical cable (16) characterized in that each electrical equipment (14) is in accordance with any one of the preceding claims, and each electrical cable (16) is disposed within a passage duct (36) for at least one electrical equipment (14) corresponding.

The electrical system (10) of claim 9, wherein each electrical cable (16) has two ends (20, 26) for connection to a power source (12), and each electrical cable (16). is provided, in at least one (26; 20, 26) of its ends (20, 26), with a connector (24; 24, 100) adapted to be coupled in a humid medium with a complementary connector (22; 22, 102) equipping the power source (12).

1 1. - Electrical system (10) according to claim 10, wherein each electrical cable (16) is provided, at one (20) of its ends (20, 26), with an indenter (18) for electrical coupling in dry medium with a complementary connector inside the power source (12).

12. - electrical system (10) according to claim 10, wherein at least one electrical cable (16) is provided at each of its ends (20, 26), a connector (24, 100) adapted to be coupled in a humid environment with a complementary connector (22, 102) fitted to the power source (12).

13. - Electrical system (10) according to any one of claims 9 to 12, wherein the electrical system (10) further comprises a power source (12), connected to each electrical equipment (14) via the or the electric cables (16).

14. An electrical system (10) according to any one of claims 9 to 13, wherein each electrical cable (16) comprises a single electrical conductor (40).