Cable connector system for floating offshore platforms

Abstract

The present invention relates to a cable connector system for connecting power cables in a cable connector channel extending from the bottom of a floating offshore platform, the cable connector system comprising an insert connector inserted into the cable connector channel, a cable pull-out section fixed to the power cable, a plurality of pull-in ropes extending adjacent to each other between the insert connector and the cable pull-out section, and a cable protector on the cable pull-out section, wherein the insert connector, pull-in ropes, cable pull-out section, and cable protector define a continuous cable passage section of an internal cable passage for the power cable.

Description

Background Art

[0001] The present invention relates to a cable connector system for connecting a power cable to a cable connector channel of a floating ocean platform. The floating ocean platform is used to support a wind turbine. The cable connector channel typically extends from the bottom of the floating ocean platform and is inserted into the water. The power cable connects the wind turbine to an offshore power grid.

Summary of the Invention

[0002] A known cable connector system includes an insert connector for insertion into a cable connector channel and a bend stiffener that hangs downwards from the insert connector. The power cable is passed through and connected to the cable connector system before being installed under the floating ocean platform. The insert connector is fixed in the water within the cable connector channel by a plurality of latches. The power cable is passed through an upper support at the upper end of the cable channel, and the termination or stripping is performed to expose the conductor. There is a possibility that the latch may fail during the service life of the floating ocean platform, and in that case, the latch can only be released by an expensive utility-class underwater remotely operated vehicle (ROV). In practice, the insert connector can only be removed in a destructive manner. If it is necessary to temporarily disconnect the power cable during the service life of the floating ocean platform, the cable is cut under the upper support, thereby losing a part of the power cable. Therefore, the power cable is initially operated with a certain margin, and when reconnecting after a temporary disconnection, it is necessary to perform the termination again and readjust the cable configuration under the floating ocean platform, which is a costly ocean operation.

[0003] The object of the present invention is to provide a cable connector system for connecting power cables to cable connector channels of a floating offshore platform, in which the power cables can be reversibly connected to and disconnected from the floating offshore platform.

[0004] According to a first embodiment, the present invention provides a set comprising a floating offshore platform having a cable connector channel opening at the bottom of the floating offshore platform, and a cable connector system for connecting power cables within the cable connector channel, the cable connector system comprising an insert connector inserted into the cable connector channel, a cable pull-out section fixed to a power cable, a plurality of pull-in ropes extending adjacent to each other between the insert connector and the cable pull-out section, and a cable protector on the cable pull-out section, the insert connector, pull-in ropes, cable pull-out section, and cable protector defining a continuous cable passage section of an internal cable passage for power cables.

[0005] The cable connector system according to the present invention comprises a cable pull-out section fixed to a power cable and an insert connector suspended from the cable pull-out section by a pull-in rope. Therefore, equipment such as an underwater latch to keep the insert connector inserted in the cable connector channel is not required. The power cable can be detached from the floating offshore platform by lowering the cable pull-out section to which it is fixed. The end of the cable is protected by a cable protector on the cable pull-out section. The entire cable can be sunk to the seabed and recovered without damage, and its entire length can be reused without cutting. In this way, the power cable can be reversibly connected to and disconnected from the floating offshore platform without requiring the intervention of potentially expensive, practical-grade underwater remotely operated equipment or adjustments to the cable configuration beneath the platform.

[0006] In one embodiment, the pull-in ropes extend parallel to each other.

[0007] In one embodiment, the pull-in rope is arranged around the cable passage it defines.

[0008] In one embodiment, the pull-in rope is evenly distributed around the cable passage it defines.

[0009] In one embodiment, the insert connector includes an insert plug for inserting into the cable connector Channel.

[0010] In one embodiment of the present invention, the insert connector comprises a radially projecting flange having a larger radius dimension than the insert opening toward the cable connector channel. This projecting flange prevents the insert connector from being inserted too deeply into the insert channel at the bottom of the floating offshore platform during the installation of the cable connector system.

[0011] In one embodiment, the insert plug has a distal end having an outer diameter at the distal end and a proximal end having a larger proximal outer diameter. If the cable connector channel has corresponding different diameters at the distal end position and the proximal end position, the proximal and distal ends of the insert plug engage with the insert channel substantially synchronously only in the final stage of insertion, thereby facilitating proper insertion of the insert plug.

[0012] In one embodiment, the cable connector system includes a bend restrictor portion between the cable outlet portion and the insert connector, which defines the cable passage portion of the internal cable passage.

[0013] In one embodiment of the present invention, the bend restrictor section comprises a series of interconnected bend restrictor links, each of which is provided with a pull-in rope channel through which a pull-in rope passes. The pull-in rope can maintain the alignment of the bend restrictor links before the power cable is inserted into the internal cable passage.

[0014] In this embodiment, the bend restrictor link includes a female component that merges with a male component and extends into the female component of a subsequent bend restrictor link.

[0015] In this embodiment, the female component comprises an internal insert channel, and the male component comprises a radially extending rim that is confined within the insert channel with play in the direction of the internal cable passage.

[0016] In one embodiment, the cable connector system includes a bend stiffener connected to an insert connector, which defines the cable path portion of the internal cable passage.

[0017] In one embodiment, the cable passage portion of the bend stiffener is at a predetermined orientation angle with respect to the cable passage portion of the insert connector.

[0018] In one embodiment, the bend stiffener is connected to the insert connector via a spool piece that sets the orientation angle.

[0019] In one embodiment, the cable protector is removably attached to the cable outlet so as to expose the distal end of the power cable after the cable outlet has been fixed to the cable connector channel. The cable protector can be reinstalled after the power cable has been removed from the floating offshore platform.

[0020] In one embodiment, the cable protector comprises a protective tube that encloses the end of the power cable and a distal hoist coupling provided on the protective tube for suspending the cable connector system. The entire assembly of the power cable and the cable connector system is suspended at the distal hoist coupling by a lifting cable that descends, for example, through the cable connector channel.

[0021] In one embodiment, the cable outlet section comprises a fixing bush surrounding the cable passage of the internal cable passage and an insert slot that opens radially and is radially accessible for inserting a hang-off lock.

[0022] In one embodiment, the cable connector system includes a guide that is detachably mounted around the connection between the cable outlet and the cable protector.

[0023] In one embodiment, the floating offshore platform comprises a circumferential wall, a bottom wall, and at least one column including a cable connector channel that penetrates the column and extends from the bottom wall, the cable connector system having an installed state in which insert connectors are inserted into the cable connector channel and suspended from the cable outlet via pull-in cables that penetrate the cable connector channel, and an unconnected state in which the cable connector system is outside the cable connector channel.

[0024] In this embodiment, the insert connector comprises an insert plug inserted into a cable connector channel, and distal and proximal elastic bodies extending around the insert plug at a distance from each other, wherein in the installed state, the distal and proximal elastic bodies are pressed against and in contact with the inner surface of the cable connector channel.

[0025] According to one embodiment, the floating offshore platform comprises a central column, a plurality of peripheral columns extending circumferentially around the central column, radially extending outriggers connecting the peripheral columns to the central column, and tendons spanning between each pair of adjacent peripheral columns.

[0026] According to a second embodiment, the present invention provides a cable connector system for use in a set according to the first embodiment of the present invention.

[0027] According to a third embodiment of the present invention, the present invention provides a method for connecting a power cable to a floating offshore platform using a cable connector system. The floating offshore platform includes a cable connector channel opening at the bottom of the floating offshore platform, and the cable connector system includes an insert connector for insertion into the cable connector channel, a cable pull-out section fixed to a power cable, a plurality of pull-in ropes extending adjacent to each other between the insert connector and the cable pull-out section, and a cable protector on the cable pull-out section, wherein the insert connector, pull-in ropes, cable pull-out section, and cable protector define a continuous cable passage section of an internal cable passage for the power cable. The method includes the steps of inserting the power cable into the internal cable passage and fixing the inserted power cable to the cable pull-out section, and lifting the cable connector system into the cable connector channel from below the bottom of the floating offshore platform using a lifting cable that passes through the cable on the cable protector. The insert connector remains suspended on the pull-in ropes even after it has reached its final insertion position.

[0028] According to a fourth aspect, the present invention provides a method of disconnecting a power cable on a floating ocean platform using a cable connector system. In this method, the floating ocean platform includes a cable connector channel that opens at the bottom of the floating ocean platform, and the cable connector system includes an insert connector inserted into the cable connector channel, a cable lead-out portion fixed to the power cable, a plurality of draw-in ropes extending side by side between the insert connector and the cable lead-out portion, and a cable protector on the cable lead-out portion. The insert connector, the draw-in ropes, the cable lead-out portion, and the cable protector define a continuous cable passage portion of an internal cable passage for the power cable. This method includes the steps of disposing the cable protector on the cable lead-out portion and lowering the cable connector system from the cable connector channel using a hoisting cable on the cable protector that extends through the cable connector channel.

[0029] The various forms and features described and shown herein can be applied individually as much as possible. These individual forms, particularly the forms and features described in the appended dependent claims, can be the subject of a divisional patent application.

Brief Description of the Drawings

[0030] The present invention is described based on exemplary embodiments shown in the accompanying drawings. [Figure 1] FIG. 1 is an isometric view of a floating ocean platform supporting a wind turbine, connected to an offshore power cable by a cable connector system according to the present invention. [Figure 2] FIG. 2 is an isometric view showing only a relevant portion of the floating ocean platform of FIG. 1. [Figure 3A] FIG. 3A is an isometric view and a partial longitudinal sectional view of the central column of the floating ocean platform of FIG. 2 with the cable connector system inserted. [Figure 3B]Figure 3B is an isometric and partial longitudinal section of the central column of the floating offshore platform shown in Figure 2, with the cable connector system inserted. [Figure 4] Figure 4 is a detailed view of the central column and cable connector system shown in Figures 3A and 3B. [Figure 5] Figure 5 is a side view of the cable connector system being installed on the floating offshore platform shown in Figure 1. [Figure 6A] Figure 6A shows details of the cable connector system shown in Figure 5. [Figure 6B] Figure 6B shows details of the cable connector system shown in Figure 5. [Figure 6C] Figure 6C shows details of the cable connector system shown in Figure 5. [Figure 6D] Figure 6D shows details of the cable connector system shown in Figure 5. [Modes for carrying out the invention]

[0031] Figure 1 shows a floating offshore platform 1 in which a wind turbine 300 is supported to form a floating wind turbine 5 in this example. The wind turbine 300 has a vertical tower 301, a nacelle 302, and a rotor 303. The rotor 303 has a hub 304 connected to a generator in the nacelle 302. In this example, the wind turbine 300 has three blades 305 extending radially from the hub 304. The wind turbine 300 can produce more than 1 MW of power, currently reaching about 10-15 MW. The base diameter of the vertical tower 301 may be 5-10 meters for wind turbines of 10 MW or more. The three blades 305 may each be more than 100 meters long. An example is General Electric's 12 MW HaliadeX turbine. Other turbine designs, such as vertical-axis wind turbines, can also be supported by the floating offshore platform 1. The wind turbine 300 is connected to the offshore power grid by a power cable 90 attached to the floating offshore platform 1 by a cable connector system 100 according to the present invention.

[0032] Figure 2 shows the floating offshore platform 1 with the wind turbine 300, walkways, handrails, and attached equipment removed to illustrate the structural components.

[0033] As shown in Figures 2, 3A, and 3B, the floating offshore platform 1 comprises a steel central column 10 having a central axis B. The central column 10 has a vertical cylindrical upper circumferential wall portion 11 closed by an upper wall 17, which in this embodiment is connected downwards via a flared wall portion or a conically expanding intermediate circumferential wall portion 12 to form a vertical cylindrical lower circumferential wall portion 13, the lower part of which is closed by a bottom wall 14 to form an internal chamber 16. The diameter of the upper circumferential wall portion 11 of the central column 10 is approximately equal to the bottom diameter of the vertical tower 301, and the diameter increases toward the bottom or keel of the central column 10 via the conically expanding intermediate circumferential wall portion 12. The central column 10 may be provided with a larger diameter foundation (not shown) below the bottom wall portion 13. This foundation wall portion 13 provides additional volume. When the foundation is filled with air, it helps to support the weight of the wind turbine 300. When the foundation is filled with water, the stability of the floating wind turbine 5 is improved. Alternatively, the central column 10 has a vertical cylindrical wall having a constant diameter over its entire height, which is preferably approximately equal to the diameter of the base of the vertical tower 301.

[0034] As shown in Figure 2, the floating offshore platform 1, in this example, comprises three vertical cylindrical stabilizing columns or peripheral columns 30 made of steel with a central axis A. The peripheral columns 30 are arranged radially around the central column 10 at 120-degree intervals, with their central axis A extending parallel to the central axis B of the central column 10. Each peripheral column 30 has a vertical cylindrical peripheral wall 31 that is closed on its upper side by an upper wall 32 to form an internal chamber 34. Inside the internal chamber 34, the peripheral columns 30 have a watertight flat section just below the mean draft W, through which the internal chamber 34 is open to the sea. The peripheral columns 30 have a skirt 33 along the lower edge of the peripheral wall 31.

[0035] The floating offshore platform 1 includes three outriggers 50 that extend radially between the central column 10 and the surrounding columns 30. The outriggers 50 are made of steel and consist of an upper tubular member 51 and a lower tubular member 52, which in this example extend parallel to each other and are interconnected by diagonal braces 53. Alternatively, at least one of the upper tubular member 51 and the lower tubular member 52 may be oblique to the other. Alternatively, the upper tubular member 51 and the lower tubular member 52 may be individual members that are not interconnected by braces.

[0036] The floating offshore platform 1 comprises three elongated upper structural members or tendons 60 of the same length that are pre-tensioned and connect the upper ends of the surrounding columns 30, and three elongated lower structural members or tendons 65 of the same length that are pre-tensioned and connect the lower ends of the surrounding columns 30 in the skirt 33.

[0037] The base diameter of the central column 10 is a maximum of 20 meters. The combined height of the central column 10 and the surrounding columns 30 is typically 20-30 meters, and in this example, it is approximately 24 meters. The diameter of the surrounding columns 30 is 6-12 meters. The lengths of the tendons 60 and 65 are 60-90 meters, respectively.

[0038] As shown in Figure 3B, the central column 10 includes an intermediate platform 18 extending parallel to the upper wall 17 and the bottom wall 14. In this example, the intermediate platform 18 is connected to the joint of the upper peripheral wall 11 and the intermediate peripheral wall 12. In this example, the central column 10 includes one internal cable connector channel 20 having a circular cross-section and extending parallel to the centerline B of the central column 10 with its central axis C offset. In this example, the cable connector channel 20 is formed by a steel insert tube 21 having a first inner diameter D1 that penetrates the bottom wall 14 and protrudes into the sea through a bottom opening 27. The insert tube 21 joins a longer steel riser tube 23 having a smaller second inner diameter D2 that penetrates the main channel W via a steel conical reduced-diameter section 22. The riser pipe 23 is welded through the intermediate platform 18 and discharged through an upper opening 25 above the main channel W at a height that ensures seawater remains within the cable connector channel 20, even if seawater temporarily rises above the main channel W due to, for example, the impact of waves. The riser pipe 23 joins a mounting flange 26 that extends around the upper opening 25. The cable connector system 100 includes a hang-off lock 101 on the mounting flange 26, which is shown in detail in Figure 6A. In this example, the hang-off lock 101 comprises two mating lock bodies 102 formed from a flat steel plate to form a split flange, which together cover the entire mounting flange 26. Each lock body 102 is provided with an inner recess 103 with a certain radius, which together form a circular inner lock passage 104.

[0039] The central column 10 comprises, in this example, a hoisting winch 106 installed on the intermediate platform 18, a hoisting sheave 107 above the cable connector channel 20 suspended from the upper wall 17, and a hoisting cable 108 on the hoisting winch 106, the hoisting cable 108 being routed along the hoisting sheave 107 and hanging directly above the center of the cable connector channel 20. The area between the upper wall 17 and the intermediate platform 18 forms a workspace where workers can walk and operate the hoisting winch 106, install the hang-off lock 101, and connect the power cable 90 to the electrical equipment and wind turbine 300 of the floating offshore platform 1.

[0040] A cable connector system 100, comprising a power cable 90 inserted into a cable connector channel 20, is shown in detail in Figures 5 and 6A-6D. The power cable 90 comprises a plurality of bendable or flexible electrical conductors 91, each conductor 91 comprising a conductive core 92 and an electrically insulating jacket 93. The power cable 90 comprises a reinforced or strengthened sheath 95 around the bundled flexible electrical conductors 91.

[0041] The cable connector system 100 includes an insert connector 110 inserted into the cable connector channel 20 in the winding direction H. The insert connector 110 includes a rigid insert plug 111 having a circular cross-section. The insert connector 110 may be made of steel. In this embodiment, the insert plug 111 includes a proximal tube 112 having a first outer diameter E1, which merges with a longer distal tube 114 having a smaller second outer diameter E2 via a conical reduced-diameter portion 113. The insert plug 111 includes a bottom flange 116 around the bottom of the proximal tube 112. In this embodiment, the insert connector 110 includes a tubular distal elastic body 115 around the end of the distal tube 114, thereby giving the insert connector 110 a locally larger initial outer diameter E3 relative to the distal tube 114, which can be reduced by reversible radial compression. In this embodiment, the insert connector 110 is provided with a tubular proximal elastic body 119 around the proximal tube 112, thereby giving the insert connector 110 a locally larger initial outer diameter E4 relative to the proximal tube 112, and this outer diameter E4 can be reduced by radial press-fitting. The insert plug 111 has an internal insert connector channel 117 along the central axis C, which forms a cable passage through which the power cable 90 passes.

[0042] The cable connector system 100 includes a flexible bend stiffener 130 having a central axis D, which is connected to a bottom flange 116 via a spool piece 140. The bend stiffener 130 is made of flexible plastic or synthetic rubber, such as flexible polyurethane (PU). The bend stiffener 130 includes a cylindrical portion 131 that transitions into a longer conical portion 132. The bend stiffener 130 has an internal bend stiffener channel 133 having a central axis D, through which a cable passage portion is formed, through which the power cable 90 extends. The spool piece 140 is made of steel and includes an upper flange 141 attached to the lower flange 116 of the insert plug 111, a lower flange 142 attached to the bend stiffener 130, a bend tube 143 connected to and protruding through the upper flange 141 and lower flange 142, and several reinforcing members 144 extending radially around the bend tube 143 and welded to the bend tube 143, the upper flange 141, and the lower flange 142. The spool piece 140 holds the internal bend stiffener channel 133 at a constant, well-defined bending angle Q relative to the internal insert connector channel 117. In this example, this bending angle Q is not 180 degrees, but for example, 150 degrees. The cable connector channel 20 and the insert connector 110 are provided with an orientation mechanism that imposes an azimuth angle R between the cable 90 and the marine platform 1. In this example, this orientation mechanism consists of a guide rim 24 in the insert tube 21 that engages with a protruding notch 118 of the insert connector 110. The bending angle Q and azimuth angle R are defined by the three-dimensional trajectory of the suspended power cable 90 from end to end as it passes through seawater.

[0043] The cable connector system 100 includes a steel cable outlet section 150. The cable outlet section 150 comprises a lower mounting flange 151 having a plurality of mounting holes 152 and a smaller upper mounting flange 159, which are integrated into a cylindrical fixing bush 154, the fixing bush 154 having an internal passage 155 through which the power cable 90 is inserted. In this example, the internal passage 155 is conical, and its inner diameter decreases downward toward the bend stiffener 130. In this example, the power cable 90 is fixed to the cable suspension section 150 by a wedge body (not shown) fixed between the power cable 90 and the internal passage 155. Alternatively, a resin body is formed between the power cable 90 and the internal passage 155. The cable suspension section 150 comprises two rims 157 that project parallel to the fixing bush 154 and are spaced apart from each other, defining a radially open insert slot 158 ​​that extends along the circumference of the fixing bush 154 and is radially accessible. The diameter of the bottom of the insert slot 158 ​​matches the inner diameter of the locking passage 104 of the hang-off lock 101. The cable outlet section 150 forms a single unit in this example, but it may instead be formed by mating components that are mounted together around the power cable 90 to form the cable outlet section 150.

[0044] The cable connector system 100 comprises a plurality of flexible pull-in cables or pull-in ropes 160 extending parallel to each other between an insert connector 110 and a cable outlet 150. In this example, the cable connector system 100 comprises four pull-in ropes 160 evenly distributed around a power cable 90, forming a cable passage for the power cable 90. In this example, the pull-in ropes are synthetic fiber ropes, such as Dyneema ropes. Each pull-in rope 160 has one end connected to the distal end of the insert connector 110 and the other end connected to a bottom mounting flange 151. In this example, the pull-in ropes 160 extend through mounting holes 152 in the bottom mounting flange 151, into which a cable clamp (not shown) engages with the pull-in rope 160.

[0045] The cable connector system 100, in this example, includes two bend restrictor sections 170 between the insert connector 110 and the cable outlet section 150. The bend restrictor sections 170 are made of rigid plastic and each comprises a series of interconnected bend restrictor links 172. Details of the bend restrictor links 172 are shown in Figures 6C and 6D. The bend restrictor links 172 extend around the power cable 90 and, in this example, have a cylindrical outer surface. The bend restrictor links 172 include a female component 173 having an inner insert channel 175 that extends circumferentially. The female component 173 merges with a male component 176 with a smaller outer diameter, the distal end of which merges with a circumferential and radially extending rim 177 that is confined within the insert channel 175 with axial play. This allows the interconnected bend restrictor links 172 to follow and restrict any bends in the power cable 90 along the entire length of the bend restrictor section 170. The bend restrictor link 172 has an inner channel 179 that forms the cable passage for the power cable 90. The bend restrictor link 172 includes a pull-in rope channel 178 that passes through the female component 173. The pull-in rope 160 passes through the pull-in rope channel 178 and is fixed therein to maintain the alignment of the bend restrictor section 170 and the power cable 90. In this example, the cable connector system 100 includes one bend restrictor section 170 on the cable outlet section 150 and one bend restrictor section 170 on the insert connector 110. Alternatively, the cable connector system 100 includes one continuous bend restrictor section 170 along the entire length between the cable outlet section 150 and the insert connector 110.

[0046] The cable connector system 100 includes an optional steel cable protector 190 that is temporarily attached to the cable outlet 150. The cable protector 190 includes a protective tube 191 that forms an internal cable passage in which the power cable 90 is completely enclosed at the location of the exposed electrical conductor 91, a lower mounting flange 192 that is bolted to an upper mounting flange 159 of the cable outlet 150, and an upper mounting flange 193 that is attached to a hoist coupling 195 with a terminal hoist eye 196. The cable connector system 100 also includes a steel guide 200 that is temporarily attached to the cable outlet 150 and the cable protector 190. The guide 200 includes a conical head 201, a cylindrical wall 202, and an inward-facing rim 203 that extends into the cable insert slot 158. The guide 200 consists of a plurality of mating parts connected to each other around the cable outlet 150.

[0047] The cable connector system 100 can be used to connect power cables 90 to the floating offshore platform 1 during commissioning of a newly constructed offshore wind power plant. Furthermore, the power cables 90 can be temporarily cut and reconnected offshore, and because it is completely reversible, there is no need to cut and discard any portion of the power cables 90.

[0048] During the commissioning phase of the floating offshore platform 1, the entire cable connector system 100 is connected to the power cable 90, for example, on land or on an anchor handling vessel. The hoisting cable 108 is unfurled from the cable connector channel 20, recovered using an underwater remotely operated vehicle (ROV) or the like, brought onto the ship, and connected to the hoisting eye 196. The power cable 90 and the cable connector system 100 are pushed out of the ship. The hoisting cable 108 is wound up in the hoisting direction H by the winch 106, and the power cable 90 is guided underwater toward the cable connector channel 20. The cable protector 190 enters the cable connector channel 20 first, followed by the protective cable pull-out section 150, the bend restrictor section 170, and finally the insert connector 110. In the final stage of inserting the insert connector 110 into the cable connector channel 20, the distal elastic body 115 slides along the conical reduced-diameter section 22 and is pressed into the riser tube 23, and the proximal elastic body 119 is pressed into the insert tube 21, securely fixing the insert connector 110 into the cable connector channel 20. The bottom flange 116 prevents the insert plug 111 from going too deep into the cable connector channel 20, although in practice a clearance remains between the bottom flange 116 and the bottom wall 14. In this final position, the cable outlet section 150 passes through the mounting flange 26 of the intermediate platform, allowing the guide 200 to be removed by the operator, and the hang-off lock 101 is installed by inserting and receiving two locking bodies 102 on the mounting flange 26 into the insert slots 158 of the cable outlet section 150 in the radial insert direction L. The locking bodies 102 can be fixed to the mounting flange 26, for example, by bolts. After the hang-off lock 101 is installed, the cable protector 190 is removed, exposing the electrical conductor 91 for connection to the electrical equipment of the floating offshore platform 1 and the wind turbine 300.

[0049] If it is necessary to remove the power cable 90 from the floating offshore platform 1, the electrical conductor 91 can be disconnected from the electrical equipment, the cable protector 190 can be attached to the cable exit section 150 and lifted slightly, the hang-off lock 101 can be released and the guide 200 can be attached, and then the power cable 90 with the cable connector system 100 can be lowered and sunk to the seabed for later recovery.

[0050] It should be understood that the above description is intended to illustrate the operation of preferred embodiments and does not limit the scope of the invention. From the above discussion, many variations that fall within the scope of the invention will be apparent to those skilled in the art.

Claims

1. A set comprising a floating offshore platform having a cable connector channel opening at the bottom of the floating offshore platform, and a cable connector system for connecting a power cable into the cable connector channel, wherein the cable connector system comprises an insert connector inserted into the cable connector channel, a cable pull-out section fixed to the power cable, a plurality of pull-in ropes extending adjacent to each other between the insert connector and the cable pull-out section, and a cable protector provided on the cable pull-out section, wherein the insert connector, the pull-in ropes, the cable pull-out section, and the cable protector define a downstream cable passage section for the internal cable passage for the power cable.

2. The set according to claim 1, wherein the pull-in ropes extend parallel to each other.

3. The set according to any one of the preceding claims, wherein the pull-in ropes are arranged around the cable passage defined by them.

4. The set according to any one of the preceding claims, wherein the pull-in ropes are evenly distributed around the cable passages they define.

5. The set according to any one of the preceding claims, wherein the insert connector comprises an insert plug that is inserted into the cable connector channel.

6. The set according to claim 5, wherein the insert connector comprises a radially projecting flange having a radial size larger than the insert opening toward the cable connector channel.

7. The set according to claim 5 or 6, wherein the insert plug has a distal end having a distal outer diameter and a proximal end having a proximal outer diameter larger than that.

8. The set according to any one of the preceding claims, wherein the cable connector system comprises a bend restrictor between the cable outlet portion and the insert connector, which defines the cable passage portion of the internal cable passage.

9. The set according to claim 8, wherein the bend restrictor comprises a series of interconnected bend restrictor links, each having a pull-in rope channel through which the pull-in rope extends.

10. The set according to claim 9, wherein the bend restrictor link has a female part connected to a male part, and the male part extends into the female part of a subsequent bend restrictor link.

11. The set according to claim 10, wherein the female portion comprises an internal insert channel, and the male portion comprises a radially extending flange that is housed within the insert channel with play in the direction of the internal cable passage.

12. The set according to any one of the preceding claims, wherein the cable connector system comprises a bend stiffener connected to the insert connector and defining the cable passage portion of the internal cable passage.

13. The set according to claim 12, wherein the cable passage portion of the bend stiffener is positioned at an orientation angle with respect to the cable passage portion of the insert connector.

14. The set according to claim 13, wherein the bend stiffener is connected to the insert connector via a spool piece that determines the orientation angle.

15. The set according to any one of the preceding claims, wherein the cable protector is detachably attached to the cable outlet.

16. The set according to any one of the preceding claims, wherein the cable protector comprises a protective tube for housing the end of the power cable and a distal hoist coupling provided on the protective tube for lifting the cable connector system.

17. The set according to any one of the preceding claims, wherein the cable outlet portion comprises a fixing bush that defines the boundary of the cable passage portion of the internal cable passage, and an insert slot that opens radially and is radially accessible for inserting an outlet lock.

18. The set according to any one of the preceding claims, wherein the cable connector system comprises a guide that is detachably attached around the connection between the cable outlet and the cable protector.

19. The floating offshore platform comprises at least one column having a peripheral wall, a bottom wall, and a cable connector channel extending through the column and opening through the bottom wall, wherein the cable connector system has an installed state in which the insert connector is inserted into the cable connector channel and suspended from the cable outlet via the pull-in cable extending through the cable connector channel, and an unconnected state in which the cable connector system is outside the cable connector channel, according to any one of the preceding claims.

20. The set according to claim 19, wherein the insert connector comprises an insert plug inserted into the cable connector channel, and a distal elastic body and a proximal elastic body extending around the insert plug at a distance from each other, and in the installed state, the distal elastic body and the proximal elastic body are pressed against and in contact with the inner surface of the cable connector channel.

21. The set according to claim 19 or 20, wherein the floating offshore platform comprises a central column, a plurality of peripheral columns provided circumferentially around the central column, radially extending outriggers connecting the peripheral columns and the central column, and tendon members stretched between each adjacent pair of peripheral columns.

22. A cable connector system for use in the set described in any one of the preceding claims.

23. A floating offshore platform is provided with a cable connector channel opening at the bottom of the floating offshore platform, and the cable connector system comprises an insert connector inserted into the cable connector channel, a cable pull-out section fixed to a power cable, a plurality of pull-in ropes extending adjacent to each other between the insert connector and the cable pull-out section, and a cable protector provided on the cable pull-out section, wherein the insert connector, the pull-in ropes, the cable pull-out section, and the cable protector define a downstream cable passage for the internal cable passage for the power cable, using the cable connector system. A method for connecting a power cable to a floating offshore platform, comprising the steps of: inserting the power cable into an internal cable passage and securing the inserted power cable to a cable outlet; and lifting the cable connector system into the cable connector channel from below the bottom of the floating offshore platform using a lifting cable provided on a cable protector extending through the cable connector channel, wherein the insert connector remains suspended from the pull-in rope after the insert connector has reached its final insert position.

24. A method for disconnecting a power cable from the floating ocean platform using the cable connector system, wherein the floating ocean platform has a cable connector channel opening at the bottom of the floating ocean platform, and the cable connector system comprises an insert connector inserted into the cable connector channel, a cable pull-out section fixed to a power cable, a plurality of pull-in ropes extending adjacent to each other between the insert connector and the cable pull-out section, and a cable protector provided on the cable pull-out section, wherein the insert connector, the pull-in ropes, the cable pull-out section, and the cable protector define a downstream cable passage for the internal cable passage for the power cable, the method comprising the steps of positioning the cable protector on the cable pull-out section and lowering the cable connector system from the cable connector channel using a lifting cable provided on the cable protector that extends through the cable connector channel.

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