Adaptive tension compensator system for offshore charging operations between vessel and offshore power plant

Abstract

An adaptive tension compensator system is provided for offshore charging a vessel via an umbilical cable of a motor-driven spool disposed at a power plant. The compensator system comprises: a motor hub member (102) mountable to a motor shaft (20) and configured to transmit rotational motion between a motor (18) and a winding drum (16) along a first rotational axis (104); a winding hub member (106) mountable to the winding drum, arranged coaxially with the motor hub member, and configured to transmit rotational motion between the winding drum and the motor; and a coupling mechanism (108) operably coupled between the winding hub member and the motor hub member, adapted to transmit rotational motion between the winding hub member and the motor hub member when the motor is in a first mode, and to transmit rotational motion between the winding hub member and the motor hub member when the motor is in a second mode. The motor hub member is adapted to provide a biased rotational movement of the winding hub member about the first axis of rotation relative to the motor hub member between a first angular position (110) and a second angular position (112).

Description

Technical Field

[0001] The present invention relates to the field of offshore charging of vessels (hybrid or fully electric) and in particular to offshore charging of vessels at an offshore location (e.g. a wind turbine or an offshore oil and gas facility) using a single umbilical cable for mooring to and charging directly from the offshore generator. In particular, the present invention relates to a tension compensation system for an umbilical cable used for both mooring and charging of a vessel at an offshore location. More specifically, the present invention relates to a passive tension compensation system. Background Art

[0002] Offshore support vessels (OSVs), service operation vessels (SOVs) or crew transfer vessels (CTVs) are often used during the construction, maintenance and operation of offshore wind farms (or any other standard or renewable offshore generators such as wave power, tidal power, solar power, fuel generators, etc.). These vessels are often used to transport technicians and other personnel and / or equipment and supplies to the site on a daily basis, or for large vessels to stay in the offshore area for several weeks. In order to reduce the carbon footprint of such offshore maintenance activities, the demand for environmentally friendly transportation (such as hybrid and fully electric OSVs, SOVs or CTVs) is growing to mitigate the negative impact of vessels powered by hydrocarbon fuels. However, the energy density of current limited battery storage severely reduces the operational capabilities and range of electric OSVs, SOVs and CTVs (eOSVs, eSOVs, eCTVs), thereby limiting the full adoption of such vessels. Therefore, offshore charging is becoming increasingly important for the charging of such eOSVs, eSOVs, eCTVs.

[0003] For example, during charging operations from a wind turbine or wind farm energy storage, the CTV can be moored to a fixed power station via dedicated mooring cables, and then use a separate umbilical cable to transfer electricity from the offshore power station to the vessel. The ship's motion caused by changing sea conditions (waves, wind, swells, etc.) can make it difficult to control the position of the ship relative to the power station, i.e., the relative distance and direction between the ship and the power station when the umbilical cable and mooring cable are connected to the power station during charging. Separate elastic composite mooring cables are often used to avoid cable failures because they absorb potentially destructive tension from the separately connected charging cable (which has a high axial stiffness). However, the use of multiple separate cables carries the risk of entanglement themselves. In addition, in the event of a cable failure, the potential snapback of the elastic mooring cables can pose a significant risk to personnel.

[0004] Active compensation is essential in situations where one is trying to moor a vessel with a single, relatively inelastic charging cable and avoid potential entanglement problems. Here, the reel 16 is actively driven by an electric motor 18 and its variable speed drive unit in a so-called "torque control" mode, where a controller monitors the torque on the reel 16 (caused by the tensioned cable) and drives the reel motor so as to keep the cable tension within predetermined limits. However, active tension control presents a significant risk in the event of a system failure, i.e. a power supply and / or motor drive failure during operation. Such a failure can have serious consequences, not only risking damage to the system, but also endangering personnel safety.

[0005] It is therefore an object of the present invention to provide an improved system and method for charging a CTV (or eCTV) at an offshore location (e.g. a wind farm) which avoids or at least minimizes the disadvantages and potential risks of the systems known in the prior art. In particular, it is an object of the present invention to provide a system which provides a simple and safe connection between a vessel and a power station using an umbilical charging cable as both a mooring cable and a charging cable. Summary of the invention

[0006] An aspect of the invention is set out in the independent claim.

[0007] According to one aspect of the present invention, there is provided an adaptive tension compensator system for offshore charging of a vessel via an umbilical cable of a motor-driven reel disposed at a power station, the system comprising:

[0008] a motor hub member mountable to the motor shaft and configured to transfer rotational motion between the motor and the winding drum along a first rotational axis;

[0009] a winding hub member mountable to the spool, disposed coaxially with the motor hub member, and configured to transmit rotational motion between the spool and the motor; and

[0010] A coupling mechanism is operably coupled between the winding hub member and the motor hub member, adapted to transmit rotational motion between the winding hub member and the motor hub member when the motor is in a first mode, and adapted to provide offset rotational motion of the winding hub member about the first rotation axis between a first angular position and a second angular position relative to the motor hub member when the motor is in a second mode.

[0011] This provides the advantage of a single umbilical charging cable that serves as both a mooring cable and a charging (power) cable, eliminating the risk of entanglement and potential damage (due to excessive tension). In addition, the system of the present invention provides a charging cable that typically has a relatively high axial stiffness to protect the "power" core from excessive strain, an elastic feature or flexibility (i.e., the introduction of "elasticity") that is typically only exhibited in elastic mooring cables. This increased elasticity reduces the axial and lateral loads on the cable, for example in wave conditions. In addition, the system of the present invention advantageously provides passive compensation, i.e., compensation activation that is independent of any power supply, making the system safer, more reliable and cost-effective, especially in the event of power outages or other failures that may occur when the vessel is connected to a power station. In addition, the present invention provides a highly adaptable compensation system that can seamlessly switch between different modes for different uses. For example, in a first mode, the winding drum is actively coupled to a motor drive, allowing the motor to actively drive the winding drum (e.g., to pay out / retract the cable, or to provide active compensation), or simply to idle the winding drum around its axis of rotation (motor idling). In the second mode, the reel is allowed to be biased disengaged from the motor drive, thereby introducing a predetermined "springiness" into the connected charging cable during use.

[0012] Advantageously, the coupling mechanism comprises a first elastic energy storage system adapted to elastically resiliently bias the winding hub member towards the first angular position.

[0013] Preferably, the first elastic energy storage system comprises at least one first accumulator configured to provide a predetermined one-way spring force in response to the rotational movement of the winding hub member relative to the motor hub member from the first angular position toward the second angular position. Even more preferably, the first accumulator is any one of a piston accumulator, a diaphragm accumulator, a bladder accumulator, a spring accumulator, and a gas-filled accumulator.

[0014] Advantageously, the first elastic energy storage system comprises at least two diametrically opposed first accumulators, each accumulator being adapted to provide the predetermined unidirectional spring force in synchronism with the other accumulator.Preferably, the at least one first accumulator is operably coupled to a hydraulic cylinder or a pneumatic cylinder.

[0015] Advantageously, the motor shaft is actively or passively rotatable when the motor is in said first mode, and wherein the motor shaft is rotationally locked when the motor is in said second mode.

[0016] This provides the advantage that the reel can be driven by a motor to actively pay out or reel in the charging cable, and also provide a rotational bias to the axially loaded charging cable within a predetermined angular range without requiring any adjustments or changes to the coupling mechanism between the reel and the motor drive.

[0017] Advantageously, the adaptive tension compensator system further comprises a gear mechanism operatively coupled between the motor shaft and the winding hub member and adapted to provide a predetermined transmission ratio between the motor shaft and the winding drum. Preferably, the gear mechanism is a planetary gear mechanism.

[0018] This provides the advantage of a different (eg increased) biased rotational range of the winding drum when the motor is in the second mode.The gear mechanism may be a variable gear mechanism adapted to provide a plurality of different gear ratios.

[0019] Advantageously, the adaptive tension compensator system further comprises a stopper assembly adapted to stop the rotational movement of the winding hub member at the second angular position relative to the motor hub member. Preferably, the stopper assembly comprises a contact element coupled to the winding hub member, and a surface element coupled to the motor hub member adapted to stopably engage with the contact element when the winding hub member is rotationally moved to the second angular position relative to the motor hub member.

[0020] Advantageously, the adaptive tension compensator system includes a cable suspension mechanism configured to guide and suspendingly engage the umbilical cable of the winding drum, the cable suspension mechanism including a suspension arm operably connected to a support frame of the motor-driven winding drum and configured to move in an offset manner between an upper arm position and a lower arm position about a pivot axis arranged parallel to the rotation axis.

[0021] This provides the advantage of additional compliance or "springiness" to the connected charging cable which complements the winding drum compensator and guides or constrains the charging cable within a predetermined range of motion.

[0022] Advantageously, the cable suspension mechanism comprises a second elastic energy storage system adapted to elastically resiliently bias the suspension arm towards the lower arm position. Preferably, the second elastic energy storage system comprises at least one second accumulator configured to provide a second unidirectional spring force in response to pivotal rotation of the suspension arm about the pivot axis.

[0023] Advantageously, the adaptive tension compensator system further comprises a slewing mechanism operably mounted between the power station and the motor-driven winding drum and configured to allow the motor-driven winding drum to rotate about a second rotation axis perpendicular to the first rotation axis.

[0024] Advantageously, the adaptive tension compensator system further comprises a sliding mechanism operably mounted between the power station and the motor-driven winding drum and configured to allow the motor-driven winding drum to move along a predetermined track relative to the power station.

[0025] The advantage of the slewing and sliding mechanisms is that the winding drum is able to track the position of the vessel relative to the charging station within a predetermined range of motion, thereby minimizing the risk of potential cable damage due to excessive side loads and excessive cable fatigue caused by cyclic bending tensions and / or movement of the vessel around the power station.

[0026] Advantageously, the adaptive tension compensator system further comprises a cable connector mountable to a vessel and adapted to receive and lock an end portion of an umbilical cable of a motor-driven reel and to provide a predetermined range of motion of the received umbilical cable. Preferably, the cable connector comprises a dual-axis gimbal mechanism adapted to allow rotational movement of the cable connector about a first gimbal axis and a second gimbal axis perpendicular to the first gimbal axis. Even more preferably, the gimbal mechanism is adapted to actively and / or passively move the cable connector.

[0027] Advantageously, the cable connector comprises a flared member adapted to guidingly receive an end portion of the umbilical cable. Preferably, the cable connector comprises a docking mechanism adapted to mechanically and electrically connect with the end portion of the umbilical cable. Even more preferably, the docking mechanism is adapted to disconnect from the end portion of the umbilical cable under a predetermined pulling force acting on the umbilical cable. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Exemplary embodiments of the present invention are explained in more detail below with reference to the accompanying drawings:

[0029] Figure 1 An overview of an in-situ adaptive tension compensator system is shown, i.e. the charging cable is reeled out and coupled to the vessel's cable connector;

[0030] Figure 2 A perspective side view of an exemplary embodiment of a tension compensator system mounted on a wind turbine or generator is shown (the marine connector system is not shown);

[0031] Figure 3 Shows Figure 2(a) left view, (b) right view and (c) front view of the tension compensator system;

[0032] Figure 4 shows an exposed close-up view of a passive winding drum compensator system coupled to the winding drum but without the cable suspension mechanism and the slewing and sliding mechanisms;

[0033] Figure 5 A passive winding drum compensator system is shown removed from the winding drum and without the winding motor, (a) is a perspective side view, (b) is a left side view (from the winding drum side) and (c) is a right side view (from the motor side);

[0034] Figure 6 Shows Figure 5 A cross-sectional side view of a passive winding drum compensator system, (a) a cross-sectional front view along AA, and (b) a cross-sectional side view along BB;

[0035] Figure 7 shows a perspective side view of a passive winding drum compensator system (without the winding drum), (a) in a retracted position (the winding drum is in a first angular position) and (b) in an extended position (the winding drum is in a second angular position);

[0036] Figure 8 Schematic diagrams showing alternative coupling mechanisms (i.e., biasing mechanisms coupling the motor hub member and the winding hub member), (a) a passive compensator driven by a differential gear using a bevel gear mechanism, and (b) a passive compensator driven by a differential gear using a planetary gear mechanism (e.g., coupled between the winding hub member and the motor hub member);

[0037] Fig. 9 Shown is a cable suspension mechanism coupled to a winding drum (the winding drum compensator system, slewing mechanism and sliding mechanism have been removed), (a) is a perspective side view, and (b) is a perspective cross-sectional side view along the mid-plane;

[0038] Fig.10 A cable suspension mechanism (including a drum compensator system and a slewing mechanism and a sliding mechanism) coupled to a winding drum is shown (a) in a static position (i.e., cable tension is insufficient to initiate compensation) and (b) in a fully compensated position (i.e., cable tension is sufficient to rotate the suspension arm upward);

[0039] Fig.11 Shown are (a) the roller mechanism (winder), (b) a cross section of the bell mouth (side load detection), and (c) a detailed close-up view of the bell mouth's proximity switch and housing roller;

[0040] Fig.12Shown are (a) a perspective front side view of an adaptive tension compensator system including a slewing mechanism and a sliding mechanism, and (b) a perspective rear side view of the slewing mechanism and the sliding mechanism without a winding drum;

[0041] Fig.13 (a) to (e) show a series of perspective views of the adaptive tension compensator system in different swivel and sliding positions, and (f) a schematic diagram of the degrees of freedom (DOF) of the swivel mechanism and the sliding mechanism, as well as the winding drum (swivel) and the suspension arm (swivel);

[0042] Fig.14 A slide mechanism coupled to a wind turbine is shown (a) in a straight slide configuration, (b) in a horseshoe slide configuration, and (c) a ship following mode for the straight slide configuration and (d) for the horseshoe slide configuration;

[0043] Fig.15 Shown is a cable connector installed on a vessel (a) a perspective view of the bellmouth, (b) a cross-sectional side view of the latch and insertion mechanism through the mid-plane of the bellmouth, and (c) a perspective close-up view of the lateral control cylinder and passive side load compensator of the cable connector;

[0044] Fig.16 (a) to (g) show a series of views showing two angles of motion of the universal joint mechanism, namely, (a) to (c) the fore / aft motion of the bellmouth and (e) to (g) the right / port motion of the bellmouth;

[0045] Fig.17 A close-up side view of a latch mechanism of a cable connector is shown (a) in an open position and (b) in a closed position;

[0046] Fig.18 Shown are (a) a detailed close-up view of the insertion mechanism without the housing, and (b) a cross-sectional view of the insertion mechanism along its front plane;

[0047] Fig.19 An umbilical connector coupled to an end portion of an umbilical charging cable including a bend restrictor (or bend stiffener) is shown (a) in perspective side view, (b) in perspective front view, and (c) in cross-sectional view.

[0048] Fig. 20 A simplified schematic diagram showing the hydraulic circuit of the latch mechanism;

[0049] Fig.21 The following scenarios are shown: (a), (b) receiving an umbilical connector in the flare (funnel) of a vessel cable connector, (c), (d) latching the received umbilical connector, and (e), (f) "plugging in" the electrical connections of the received umbilical connector;

[0050] Fig. 22 A simplified schematic diagram of the electrical system architecture is shown;

[0051] Fig.23 A "flow board" overview showing the main steps of the charging process;

[0052] Fig.24 Shown with Fig.23 A “flow board” overview of the catenary control states associated with the main sequential steps shown;

[0053] Fig.25 A "flow board" overview showing the swing / slide mode of operation active at each step in the charging process;

[0054] Fig.26 A "flow board" overview of the bellmouth (funnel) operating mode active at each step of the charging process is shown;

[0055] Fig. 27 A “flow board” overview showing the sequence of steps for an active emergency release;

[0056] Fig.28 shows a simplified schematic diagram of a wireless link between a vessel (CTV) and a power station (OWT);

[0057] Fig.29 A simplified diagram showing a possible cloud architecture for a control system;

[0058] Fig.30 The steps of the charging process are shown (see Fig.23 ) is a simplified illustration of a communication flow chart;

[0059] Fig.31 Schematic diagram showing charging methods, (a) directly connected to the ship's batteries, and (b) connected to the ship's DC system to provide DC voltage, and

[0060] Figure 32 shows various screenshots of the software application: (a) location and real-time status of all nearby chargers, (b) booking schedule, (c) AC functionality; (d) location and status of vessels (CTV) near the power station (OWT), (e) booking schedule of the power station, and (f) system status of the power station. DETAILED DESCRIPTION

[0061] The abbreviations used in this manual include the following:

[0062] AHC Active Heave Compensation

[0063] BMS Battery Management System

[0064] CTV Crew Transfer Vessel

[0065] eCTV Battery Powered Crew Transfer Vessels

[0066] ER Emergency Release

[0067] FMECA Failure Mode, Effects and Criticality Analysis

[0068] MRU Motion Reference Unit

[0069] OWF offshore wind farm

[0070] OWT offshore wind turbine

[0071] OSS offshore substation

[0072] The described exemplary embodiments relate to a tension compensator system for an umbilical / cable used for both mooring and charging.

[0073] Certain terms are used in the following description for convenience only and are not limiting. The words "right", "left", "lower", "upper", "front", "rear", "upward", "lower", "downward", "above", and "below" indicate directions of reference in the accompanying drawings and are relative to the components being described when assembled and installed (e.g., in situ). The words "inward", "inwardly", "outwardly", and "outwardly" refer to directions toward and away from a designated centerline or geometric center (e.g., central axis) of the elements being described, respectively, and the specific meanings are readily apparent from the context of the specification.

[0074] In addition, as used herein, the terms "connected," "attached," "coupled," and "mounted" are intended to include a direct connection between two components without any other components interposed therebetween, as well as an indirect connection between components with one or more other components interposed therebetween. The terminology includes the words specifically mentioned above, their derivatives, and words of similar meanings.

[0075] Furthermore, unless otherwise indicated, the use of ordinal adjectives, such as "first," "second," "third," etc., merely indicates different instances of similar objects referred to and does not imply that the objects so described are necessarily in a given order temporally, spatially, ordinalally, or in any other manner.

[0076] Throughout the description and claims of this specification, the terms "comprises" and "comprising" and their variations are understood to mean "including but not limited to", and they are not intended to (and do not) exclude other parts, additives, components, integral bodies or steps. Throughout the description and claims of this specification, the singular encompasses the plural unless the context otherwise requires. In particular, where the indefinite article is used, the specification should be understood to contemplate both the plural and the singular unless the context otherwise requires.

[0077] Features, integers, characteristics, compounds, chemical moieties or groups described in conjunction with a particular aspect, embodiment or example of the invention are to be understood to be applicable to any other aspect, embodiment or example described herein unless incompatible therewith. All features disclosed in this specification (including any accompanying claims, abstract and drawings) and / or all steps of any method or process so disclosed may be combined in any combination, except combinations where at least some of such features and / or steps are mutually exclusive. The invention is not limited to the details of any foregoing embodiments. The invention extends to any novel feature or any novel combination of features of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel step or any novel combination of steps of any method or process so disclosed.

[0078] In the following description, the invention is described in the context of an offshore charging or power supply system and, therefore, a functional description of a turbine / substation offshore charging system is provided. For this specific example, the system has been developed as an enabling technology to provide offshore charging to all electric and hybrid electric wind farm support vessels and other marine vessels and is intended to be installed on a wind turbine foundation at an offshore wind farm or on an offshore substation. However, it will be appreciated by those skilled in the art that the invention is applicable to any offshore power station capable of supplying power (from conventional and / or renewable energy sources) to a charging vessel (e.g., an eCTV) via a charging cable.

[0079] In summary, the purely passive (ie independent of any electric power source) adaptive tension compensator system of the present invention provides a safe and reliable solution to protect the umbilical charging cable 14 and control mooring loads even in the event of a fault.

[0080] like Figure 1 As shown, the adaptive tension compensator system embodying aspects of the invention claimed herein includes four subsystems, (i) a drum compensator mechanism 100 coupled to a drum 16 storing an umbilical charging cable 14, (ii) a cable suspension arm 200 coupled to a drum support frame 22, (iii) a cable suspension arm 200 coupled to a power station such as a wind turbine 10 (see FIG. 1 ). Fig.14 and Fig. 22 ) and a swivel mechanism 300 and a slide mechanism 400 that operably supports the winding drum 16, and (iv) a vessel connector system 500 mounted on the vessel 12. Each of the four subsystems will be described separately.

[0081] (i) Winding drum compensator mechanism

[0082] Now refer to Figures 2 to 7The winding drum tension compensator mechanism 100 is operably coupled between the winding drum 16 and the motor shaft 20 of the motor 18 so as to transmit rotational motion between the winding drum 16 and the motor 18 .

[0083] The winding drum tension compensator mechanism 100 includes a winding hub coupling or flange member 106 mounted to the winding drum 16 and a motor hub coupling or flange member 102 mounted to the motor shaft 20 of the motor 18. The winding hub coupling 106 and the motor hub coupling 104 are both mounted coaxially with the winding rotation axis 104 between the winding drum 16 and the motor shaft 20, forming a rotatable joint between the winding drum 16 and the motor shaft 20. The winding hub coupling 106 is rotatably supported by a first bearing 26 mounted to the support frame 22 and a second bearing 28 engaging the winding hub coupling 106 and the motor hub coupling 102. In addition, the motor hub coupling 106 is rotatably supported by the second bearing 28 and a third bearing 30 disposed between the motor housing 32 and a portion of the motor hub coupling 102.

[0084] The two diametrically opposed hydraulic cylinders 118 are operably coupled to the respective accumulators 116 and are configured to provide a predetermined spring force (i.e., form an elastic energy storage system) via a piston rod 119. For each of the two opposed hydraulic cylinders 118, a proximal end of the piston rod 119 is operably (i.e., movably) coupled to a winding hub coupling member 128 that extends radially away from a distal end portion of the winding hub coupling 106. The cylinder barrel 130 is operably coupled to a motor hub coupling member 132 that extends radially from a distal end portion of the motor hub coupling 102. Thus, the two opposed hydraulic cylinders 118 are operably coupled between the winding hub coupling 106 and the motor hub coupling 102 to form a coupling mechanism 108 that allows unidirectional rotational movement of the winding hub coupling 106 relative to the motor hub coupling 102 about a common rotational winding axis 104. In particular, the hydraulic cylinder 118 and the winding hub coupling member 128 and the motor hub coupling member 132 are arranged in such a way that relative rotational movement between the winding hub coupling 106 and the motor hub coupling 102 is possible only in a first direction of the winding drum 16, i.e., the direction in which the winding drum 16 pays out the charging cable 14. When the winding drum 16 rotates in a second, opposite direction, i.e., the direction when retracting or winding the charging cable 14, the winding hub coupling member 128 stops engaging with the motor hub coupling member 132, thereby preventing any relative rotational movement between the winding hub coupling 106 and the motor hub coupling 102 in the second direction.

[0085] The angular range of the winding hub coupling 106 relative to the motor hub coupling 102 when moving in the first direction is limited by the extension length of the piston rod 119 of the hydraulic cylinder 118, but can be increased using a suitable gear mechanism between the winding drum 16 and the winding hub coupling 106.

[0086] For this particular exemplary embodiment, the hydraulic cylinder / accumulator mechanism 118, 116 (using liquid and / or gas) is used to provide elastic resistance (e.g., spring force or damping) to the rotational movement of the winding hub coupling 106 relative to the motor hub coupling 102. However, it should be understood by those skilled in the art that any other suitable biasing device, such as a spring or damping member, device, system or assembly, may be used to provide a rotational bias to the winding hub coupling 106 when moving relative to the motor hub coupling 102. For example, the bias may be provided by any one of a spring (torsion spring, helical coil, leaf spring, etc.), an elastic material (elastically stretchable or compressible), a hydraulic or pneumatic accumulator, or any combination thereof.

[0087] In this example, the hydraulic cylinder 118 is adapted to provide a 50 degree rotation of the reel 16 (e.g., having a reel radius of 0.65 meters) during the full stroke of the piston rod 119 when subjected to a 2 ton cable load, translating into a cable length of 0.60 meters released into the catenary under a 2 ton cable load. As previously described, a suitable gear mechanism coupled to the reel 16 can be used to vary (e.g., increase) the length of the payout cable.

[0088] The stop mechanism 122 is provided by a contact or bumper 124 mounted at the distal end of the winding hub coupling structure 128 and a surface element 126 mounted to the motor hub coupling structure 132 of the opposing hydraulic cylinder 118. The contact or bumper 124 is arranged to stopably engage the surface element 126 when the winding hub coupling 106 moves from a first angular position (relative to the motor hub member 102) in which the piston rod 119 is fully retracted to a second angular position (relative to the motor hub member 102) in which the piston rod 119 is fully extended.

[0089] During use, the umbilical charging cable 14 is paid out for connection with the vessel 12. The initial payout is driven by the motor 18, and once connected, the vessel 12 reels the cable 14 out while away from the power station 10. Here, the motor 18 is "switched" into a "slave mode", i.e., the motor shaft 20 is either allowed to "idle" about its rotational winding axis 104 (when rotating the winding drum 16), or the motor shaft 20 is rotated by the activated motor 18 (so as to actively drive the winding drum 16). When the motor 16 is in the "slave mode", when the winding drum 16 is rotated in a first direction (paying out the cable 14), the winding hub coupling 106 and the motor hub coupling 102 move synchronously as a unit about the rotational winding axis 104. When moving the winding drum 16 in the first direction, the biasing force provided by the elastic energy storage system 114 (i.e., the hydraulic cylinder 118 and the accumulator 116) prevents relative rotational movement between the winding hub coupling 106 and the motor hub coupling 102. When the winding drum 16 is actively driven by the motor 18 to retract the charging cable 14 in the (second direction), the biasing force of the elastic energy storage system 114 (i.e., the hydraulic cylinder 118 and the accumulator 116) prevents relative rotational movement between the winding hub coupling 106 and the motor hub coupling 102. When the winding drum 16 is actively driven by the motor 18 to pay out the charging cable 14 in the (first direction), the stoppered mating arrangement of the winding hub coupling member 128 and the motor hub coupling member 132 prevents relative rotational movement between the winding hub coupling 106 and the motor hub coupling 102.

[0090] Once the charging cable 14 is connected to the vessel 12, and the vessel 12 is a predetermined distance from the power station 10, the motor 18 is "switched" to a "mooring mode", i.e., the motor is in a standby state, and the brake is powered by its variable speed drive ("waiting" at zero speed to actively assist the passive compensator when needed), thereby allowing the reel hub coupling 106 to rotate relative to the biased "locked" motor hub coupling 102. When the umbilical cable tension increases (e.g., by wave motion) above a predetermined threshold determined by the characteristics of the elastic energy storage system 114 (i.e., hydraulic cylinder 118 and accumulator 116), the spring or damping force provided by the elastic energy storage system 114 (i.e., hydraulic cylinder 118 and accumulator 116) is overcome, and the piston rods 119 extend out of their respective cylinders 130, thereby allowing the reel 16 to rotate and pay out a length of the charging cable 14, thereby reducing the tension in the umbilical charging cable 14. When the cable tension is reduced (e.g., by wave motion), the piston rod 119 retracts into the cylinder 130, causing the reel 16 to rotate back and retract a length of the charging cable 14. The reel 16 rotates forward against the spring force (tension increases) and rotates backward (tension decreases) caused by the spring force in a reciprocating motion, such as caused by waves. Alternatively, the elastic energy storage system 114 may include one or more fluid-filled spring dampers.

[0091] Due to the limited biased rotation of the spool 16 , peak tension in the cable 14 is reduced to an acceptable (ie, safe) level, preventing or at least minimizing potential damage during charging operations.

[0092] In addition, the passive drum tension compensator 100 can be used in conjunction with active tension load compensation. For example, as the drum 16 pays out the cable 14, a suitable sensor feeds information of the cable tension to the controller, and the controller operates the drum 16 in a "constant tension" mode to automatically pay out (or retract) the charging cable 14 so as to maintain or limit the cable tension during use. Thus, by limiting the cable tension to a predetermined maximum value, active tension load compensation can be used to assist the passive drum tension compensator 100 in extreme vessel motion situations so that the cable 14 can be safely disconnected if necessary. Suitable sensors for monitoring cable tension may include feedback from load cells and stroke / pressure of the hydraulic cylinder 118.

[0093] Figure 8 Optional winding drum couplings are shown that can be used with the winding drum tension compensator 100. For example, (a) a bevel gear mechanism can be used to couple the motor 18 and winding drum 16 with the elastic energy storage system, or (b) a planetary gear mechanism can be used to couple the motor 18 and winding drum 16 with the elastic energy storage system.

[0094] (ii) Cable suspension mechanism

[0095] Reference now Figures 9 to 11 , the cable suspension mechanism 200 comprises a suspension arm 202, which is operably connected to the support frame 22 of the winding drum 16 and is configured to rotate around a rotation arm axis 212, which is arranged parallel to the rotation winding axis 104 of the winding drum 16. In addition, the suspension arm 202 is constrained by a second elastic energy storage system 207, which includes two parallel arranged hydraulic cylinders 208 connected to corresponding accumulators 210. The hydraulic cylinders 208 and the accumulators 210 are suitable for providing spring forces or damping forces, as described for the winding drum tension compensator 100. In the static position (lower arm position 206, see Fig.10 (a)), the suspension arm 202 is fully rotated downward to a substantially vertical position, wherein the hydraulic cylinder 208 is fully retracted. In the compensating arm position (upper arm position 204, see Fig.10 (b)), the suspension arm 202 is rotated upward toward a horizontal position, with the hydraulic cylinder 208 fully extended and biased back.

[0096] Especially Fig. 9 and Fig.11As shown, the suspension arm 202 also includes a bell mouth 216 at its distal end. The bell mouth 216 is formed by a plurality of rollers 218 arranged around the four sides of the bell mouth 216, and when the charging cable 14 is guided from the winding drum 16 to the vessel 12, the plurality of rollers surround the charging cable. The surrounding rollers 218 are arranged to form a bell shape, which has a wider opening at the distal end of the suspension arm 202. Each of the two lateral arrays of rollers 218 (side rollers) can be connected to a proximity switch 220, which is suitable for measuring the lateral load (to be transmitted to the controller). These switches 220 can be used to actively drive the slewing mechanism 300 and / or the sliding mechanism 400 (described in more detail in the following sections) to reduce the lateral load in the catenary. Proximity switches 220 can also be provided to the upper and lower roller arrays 218 to detect the tension load in the charging cable 14.

[0097] A low friction roller in the form of a reel 214 is also provided at the proximal tip of the suspension arm 202 and is configured to guide the charging cable 14 from the reel 16 into and out of the bellmouth 216 over the suspension arm 202. The reel 214 may be driven by a motor 222 to actively move and guide the charging cable 14 from the reel 16 toward the vessel 12. Alternatively, the reel 214 may be passively driven from the reel 16 via a chain or gear mechanism.

[0098] During use, the cable suspension mechanism 200 cooperates with the spool tension compensator 100, i.e., further increases the "springiness" of the catenary when the vessel 12 is moored to the power station 10 during charging. Specifically, as cable tension increases, the suspension arm 202 rotates upward, extending the hydraulic cylinder 208 (and the charging cable 14) to reduce the tension in the umbilical charging cable 14. The biasing force (spring / damping force) provided by the suspension mechanism 200 may be lower than the biasing force (spring / damping force) provided by the spool tension compensator 100, so that the suspension arm 202 reacts to the increase in tension before the spool tension compensator 100 is activated (i.e., a length of the charging cable 14 is paid out). However, it will be appreciated by those skilled in the art that any suitable combination (i.e., spring or damping force) between the two cooperating compensator mechanisms 100, 200 may be used without departing from the scope of the present invention, i.e., the biasing force provided by the cable suspension mechanism 200 may be greater than or equal to the biasing force of the spool tension compensator 100.

[0099] In this particular example, the suspension arm 202 may be configured to rotate upward approximately 25° (degrees) under a cable tension load of 2 tons. However, it will be appreciated that any other suitable angular range may be provided directly or via a gear mechanism.

[0100] (iii) Rotating and sliding mechanisms

[0101] Reference Figure 12 to Figure 14 The slewing mechanism 300 operably coupled to the sliding mechanism 400 is configured to (i) allow the winding drum 16 to be manually oriented toward the vessel 12 when in the propulsion / stop position, (ii) automatically (actively or passively) track or follow the vessel 12 when moving due to tidal currents or wind changes, thereby allowing the vessel to "follow the wind" around the power station 10, and (iii) provide side load protection for the engaged umbilical charging cable 14 during use.

[0102] like Fig.12 As shown, the slewing mechanism 300 includes a support platform 304 and a frame platform 306, which is adapted to receive and support the winding drum support frame 22. The frame platform 306 is operably (i.e., rotatably) coupled to the support platform 304 so as to allow rotational movement around a rotational slewing axis 308 (perpendicular to the rotational winding axis 104). A gear mechanism 310 is provided to actively drive the frame platform 306 to rotate around the rotational slewing axis using a motor (not shown). The motor (not shown) can be activated by the controller in response to a signal received from any proximity switch 220 disposed at the bell mouth 216 of the suspension mechanism 200, or in response to the cable tension measured at the winding drum tension compensator 100.

[0103] The cooperating sliding (or tracking) mechanism 400 includes a platform for mounting to a track 402 of a power station 10 (e.g., a wind turbine). A trolley or cart 404 is movably coupled to the track 402 and can be driven along the track 402 via a motor drive mechanism 406 (see FIG. Fig.12 and Fig.13 The motor drive mechanism 406 may be activated by the controller in response to a signal received from any proximity switch 220 disposed at the bell mouth 216 of the suspension mechanism 200 , or in response to cable tension measured at the winding drum tension compensator 100 .

[0104] Track 402 may have any form or shape suitable for a particular range of motion around power station 10. For example, Fig.12 , Fig.13 and Fig.14 As shown in (a) and (c), the track 402 can be a straight rail (e.g., for retrofitting) in which the trolley 404 and the winding drum 16 slide / move along a straight line. The straight track 402 can be cantilevered to the wind turbine 10, allowing the winding drum 16 to move further than the actual footprint of the power plant 10 and provide a wider range of operating angles. Fig.14 (c) shows a series of simplified illustrations of a straight track 402 and a connected vessel 12 at different following positions.

[0105] Alternatively, if Fig.14As shown in (b) and (d), the track 402 may be horseshoe shaped, or arranged in a semicircle or even a circle around the power plant 10, thereby allowing the winding drum 16 to move around the power plant 10 and providing a wider range of operating angles than a straight track. Fig.14 (d) shows a simplified illustration of the horseshoe track 402 and the connected vessels 12 at different locations around the power station 10.

[0106] In line with the slewing mechanism 300, the sliding mechanism 400 can be operated in the following modes: (i) a "manual mode", in which case the slewing and sliding mechanisms 300, 400 are completely controlled by the vessel, (ii) an "active mode", in which case the slewing and sliding mechanisms 300, 400 actively follow the movement of the vessel (controlled by a controller and sensors) so as to keep the side load or cable tension below a predetermined threshold, or (iii) a passive "following mode", in which case both the slewing and sliding mechanisms 300, 400 are configured to "idle" (i.e., around a rotating slewing axis and along a predetermined trajectory) without active control so as to simply follow the movement of the vessel 12 by being dragged by the charging cable 14.

[0107] (iv) Ship connector

[0108] Reference now Figures 15 to 21 The system of the present invention also includes a vessel connector system or assembly 500 installed on the vessel 12.

[0109] The marine connector system 500 includes a connector or docking mechanism 510 with an attached bellmouth 508. The docking mechanism 510 and bellmouth 508 are mounted to the marine vessel 12 via a gimbal mechanism 502, which is configured to allow the bellmouth 508 and the docking mechanism 510 to rotate with two degrees of freedom. In addition, the gimbal mechanism 502 includes a hydraulic cylinder 512 (coupled with a corresponding accumulator) to provide biased motion about a first gimbal axis 504 and a second gimbal axis 506. The biased rotational motion introduces further mechanical damping (i.e., introduces "springiness") to the entire adaptive tension compensator system.

[0110] like Fig.15As shown in (a), the docking mechanism 510 includes a latch 516 and an insertion mechanism 518, which are configured to receive and lockably connect the cable end connector 514 of the charging cable 14, and automatically release the locked cable end connector 514 under a predetermined tension (that is, if the umbilical cable tension reaches a level that is dangerous to the equipment, the latch 516 will automatically open). In addition, the insertion mechanism 518 is provided with a guide 526 to ensure correct connection. The control system is suitable for continuously monitoring the position of the insertion cylinder 522 and the latch cylinder 520 to ensure correct electrical connection. In the event of any unexpected movement or incomplete connection, the controller will stop the charging process.

[0111] Fig.16 The gimbal mechanism 502 is shown about its respective first gimbal axis 504 (see Fig.16 (a) to (d)) and the second cardan axis 506 (see Fig.16 (e) to (g)) provide the degrees of motion (DOF). Fig.17 The latching function (via hydraulic cylinder 520 ) when securing a received cable end connector 514 to the marine connector system 500 is shown.

[0112] Details of the umbilical cable end connector 514 are as follows Fig.18 and Fig.19 As shown. In this exemplary embodiment, the cable end connector 514 is a waterproof electrical connector (enclosure rating is at least IP67), that is, the connector 514 is self-sealing, has a wet-fit design, and is configured to allow immersion in water without damage, or without intervention after immersion and recovery. In addition, the cable end connector 514 is made of a lightweight, strong and durable material and has an expandable design suitable for handling increased power. A bend reinforcement 524 is provided at the distal end of the charging cable 14 to avoid or minimize excessive bending damage when connected to the vessel 12. The cable end connector 514 of this particular example has a DC rated voltage of up to 950VDC and has a mirrored "+ve" and "-ve" pin arrangement to enable connection of + / -180° (degrees) without polarity reversal.

[0113] Fig. 20 A schematic diagram of an example hydraulic diagram for the latch cylinder 520 is shown. Fig.21The mating process between the cable end connector 514 and the ship connector system 500 is shown. In particular, during use, (a) the cable end connector 514 approaches the flare 508 (paid out from the reel 16), then (b) enters the flare 508 (i.e., funnels into) and connects with the docking mechanism 510, wherein the latch 516 moves from its open position (c) to its closed position (d), thereby securing the cable end connector 514 to the ship connector system 500, and (e), (f) wherein the insertion mechanism 518 moves into engagement with a corresponding insertion receiver of the cable end connector 514 to provide an electrical connection between the ship connector system 500 and the umbilical charging cable 14.

[0114] The ship connector 500 is also provided with an emergency release function, which is usually a voluntary action initiated by the ship's crew, who have the ability to request an emergency release at any stage of the process. The emergency release can also be automatically initiated by the controller when a predetermined measured load is reached. The emergency release of this exemplary embodiment estimates that it takes about 2.5 seconds from its initiation to the complete electrical and mechanical disconnection of the cable end connector 514 from the ship connector 500. In the event of a major failure of the control system, or even a complete power outage, the emergency release can be triggered by initiating a manual release of the ship connector system 500.

[0115] Additionally, in the event of a high (i.e., predetermined threshold) tension load on the charging cable 14 / cable end connector 514, a passive but automatic mechanical action unlocks the latch mechanism 516 in order to release the cable end connector 514. This is a last resort to preserve the integrity of the equipment and ensure personnel safety. The overload emergency release is adapted to operate independently of any controller or power supply. However, while the controller is still operating, it will issue a warning to the crew that the tension has reached a high level and then shut down the charging process. Thus, if the predetermined tension load threshold is reached, the controller will simply initiate the ejection of the cable end connector 514.

[0116] In the event of a controller or power supply failure, the DC switchgear on the vessel 12 will simply default to opening the latch mechanism 516, thereby interrupting the charging current, assuming that the charger cannot be disabled before release due to the unavailability of the control system. In addition, when the controller is unavailable or fails and the umbilical cable tension increases beyond a predetermined safety threshold, the cable end connector 514 is automatically ejected. To do this, the pressure on the latch cylinder 520 is higher than the pressure of the accumulator, so oil is pushed into the accumulator and the latch cylinder 520 is retracted to release the cable end connector 514.

[0117] Example of charging process

[0118] Once the vessel 12 is in position at the wind turbine 10 , the cable end connector 514 is lowered from the wind turbine 10 under remote control from the vessel bridge and docked in the flare 508 of the vessel connector system 500 where it is secured by the latch 516 and electrically coupled to the insertion system 518 .

[0119] Prior to connection and before the vessel 12 approaches the wind turbine 10, the bell 508 is moved to its vertical position in preparation for the insertion of the cable end connector 514. Both the cable reel 16 on the wind turbine 10 and the bell 508 of the vessel connector system 500 have several dynamic degrees of freedom to enable the crew to perform a rough alignment of the cable end connector 514 with the vessel 12 before the cable end connector 514 enters the bell 508. The geometric configuration of the cable end connector 514 and the bell 508 ensures that once the cable end connector 514 is roughly aligned, it can be lowered into the bell 508, where it is automatically aligned and oriented during docking. The design intent is that connection and disconnection can be done "hands-free", i.e., the crew does not have to handle any connectors or cables on deck.

[0120] When the cable end connector 514 is docked in the bellmouth 508, it is locked in place by the latch mechanism 516. This is powered by a small electric HPU at the rear of the vessel connector system 500. The HPU can be located in a machine space inside the vessel 12 and, for economy, can even be shared with the vessel's crane.

[0121] In the next step, a pair of hydraulic "insertion" cylinders are moved upward to electrically mate with the cable end connector 514. The vessel 12 is now electrically and mechanically connected to the wind turbine 10, although electrical power remains isolated until the vessel 12 reaches a mooring and charging location.

[0122] At this stage, the vessel 12 is moving away from the wind turbine 10, with the reel 16 automatically paying out the umbilical charging cable 14 (i.e. under constant tension control). If desired, the reel 16 can be controlled in other modes (see previous sections), for example, a "manual" or "position control" mode, whereby the reel 14 follows the position of the vessel 12 relative to the wind turbine 10. As the vessel 12 moves away from the wind turbine 10, the flare 508 is manually or automatically lowered towards a horizontal position to ensure that the cable load path remains substantially straight. When the vessel 12 has reached its dedicated mooring and charging position, power can be "fed" to the vessel's battery storage or simply to provide an alternative source of power to the vessel's main grid.

[0123] The bellmouth 508 is mounted on a gimbal mechanism 502 that can be hydraulically operated or moved in a "floating mode" (passive motion). This allows the vessel 12 to assume a natural position relative to the wind turbine 10 while keeping the umbilical cable load path as straight as possible to avoid excessive bending of the cable 14 under tension. In this exemplary embodiment, the vessel connector system 500 is positioned completely forward along the vessel centerline and recessed so that its top is flush with the vessel deck, allowing personnel to pass over it without obstruction.

[0124] In addition, as previously described, an emergency release system is provided at the vessel connector system 500 to disconnect the vessel 12 in emergency or high tension situations due to increased weather conditions and in situations where normal disconnection is not possible. This can be manually initiated by the crew using a button on the bridge, or automatically initiated by the control system when the system is approaching its safe working load and is expected to be overloaded. In addition, in the event of a control and safety system or power failure, the disconnection can be passively initiated. In effect, this provides a manual and automatic overload protection system (MOPS / AOPS) similar to that of offshore lifting equipment. In the event of a power supply or control failure, a passive release system (discussed in the previous section) is provided to unlock and eject the cable end connector 514. During an emergency release, the power supply is disconnected before the cable end connector 514 "disengages" or disconnects.

[0125] Further detailed steps of the charging process, the operating modes, the communication protocols between the power station 10 and the vessel 12 (WiFi, Internet, Cloud), the operator interface and the booking procedure are referred to in the Appendix section. Figure 23 to Figure 3 The process board and schematic diagram shown in 2 are described in more detail.

[0126] Fig. 22 A schematic diagram of an electrical power system is shown, wherein a vessel 12 is connected to a power station 10 via a charging cable 14 .

[0127] Optional Active Heave Compensation (AHC)

[0128] The system of the present invention may be equipped with an active heave compensation (AHC) system. If desired, AHC may be used when (i) the vessel is propelling, or (ii) the vessel is stationary. Under normal circumstances, AHC is not required when propelling because the vertical motion of the vessel 12 is small. However, when propulsion is not possible, AHC will be required to compensate for the heave motion of the vessel 12 during the docking process of the cable end connector 514 and the mating mechanism 510 with the vessel connector 500. Here, a motor reference unit (MRU) will be located at the vessel 12 and the motion of the vessel will be sent to the winding drum 16 using a wireless link. The system controller may utilize a wireless communication system under the trade name XWave. TMcontrol software, which is a fully mature AHC control system platform developed and patented by MJR (see EP3303204B1), and has been used in many applications in this field.

[0129] Automatic motion compensation of the bellmouth 508 may also be provided, together with an auxiliary guidance system to ensure that the connector can be inserted into the bellmouth when the vessel is stopped and not being propelled. In this case, the controller may be equipped with a basic dynamic positioning system which, in all normal weather conditions, will automatically use the vessel's propulsion system to hold the vessel in the proper position under the reel to enable the connector to be aligned and inserted.

[0130] Optional energy management system

[0131] The system of the present invention may also be equipped with an energy management system as described in GB 2571267, the details of which are incorporated herein by reference. The inclusion of such a system would provide a self-sustaining energy source (eg derived from wave energy).

[0132] It will be appreciated by those skilled in the art that the above embodiments are described by way of example only, without any limiting meaning, and that various changes and modifications are possible without departing from the scope of the invention as defined by the appended claims. Various modifications to the detailed design as described above are possible, for example, there may be changes in shape, size, arrangement (i.e., a single integral component or two independent components), components, etc.

[0133] Reference numerals

[0134] 10 Wind Turbine Power Station 204 Upper Arm Location

[0135] 12 Ship 206 Lower arm position

[0136] 14 Umbilical cable 207 Second elastic energy storage system

[0137] 16 Winding drum 208 Hydraulic cylinder

[0138] 18 Motor 210 Second accumulator

[0139] 20 Motor shaft 212 Rotating arm axis

[0140] 22 winding drum support frame 214 winding wheel

[0141] 24 Cable end portion 216 Bell mouth

[0142] 26 Roller surrounded by first bearing 218

[0143] 28 Second bearing 220 Proximity switch

[0144] 30 Third bearing 222 Winding wheel motor

[0145] 32 Motor housing 300 Rotating mechanism

[0146] 100 Winding drum tension compensator 304 Support platform

[0147] 102 motor hub component 306 frame platform

[0148] 104 Rotational winding axis 308 Rotational rotation axis

[0149] 106 Winding hub member 310 Gear mechanism

[0150] 108 connection mechanism 400 sliding mechanism

[0151] 110 first angle position 402 track

[0152] 112 second angle position 404 pulley or cart

[0153] 114 first elastic energy storage system 406 motor drive mechanism

[0154] 116First Accumulator 500 Marine Connector System

[0155] 118 hydraulic cylinder 502 universal joint mechanism

[0156] 119 piston rod 504 first universal joint axis

[0157] 120 gear mechanism 506 second universal joint axis

[0158] 122 stopper assembly 508 bell mouth member

[0159] 124 contact element 510 docking mechanism

[0160] 126 Surface element 512 Hydraulic cylinder

[0161] 128 winding hub connecting member 514 cable end connector

[0162] 130 cylinder 516 latch mechanism

[0163] 132 Motor hub connecting member 518 Insertion mechanism

[0164] 134 bevel gear 520 latch cylinder

[0165] 136 planetary gear 522 insert cylinder

[0166] 200 Cable suspension mechanism 524 Bending reinforcement

[0167] 202 suspension arm 526 guide appendix

[0168] Fig.23 The following table shows the main steps of the charging process of the standard Centella CTV. This sequence is common to all Centella series products. Fig.23 A detailed description of each step of the process board defined in:

[0169]

[0170]

[0171] Table 1

[0172] Catenary control The Umbilical Charging Cable 14 provides:

[0173] Energy is transferred from the charger to the CTV battery.

[0174] CTV mooring cables.

[0175] Umbilical cable tension is controlled by the reel, which will take different actions depending on the specific part of the process to achieve the desired umbilical cable catenary and tension. Fig.24 The catenary control states associated with the main sequential steps are shown.

[0176]

[0177] Table 2

[0178] Fig.24 The recommended umbilical control mode for each step is shown, however, the CTV crew can always select the umbilical control mode, for example, when the vessel is moving in / out of the charging area, the crew can engage the umbilical control in speed mode, allowing the CTV to control the umbilical catenary.

[0179] Passive tension compensation for moored mode is implemented in three stages as follows:

[0180] Rotating and sliding mechanisms

[0181] The rotation and sliding system of the Centella Asiatica Station has three main functions:

[0182] • Allows the winder to be manually oriented to the CTV advance / stop position.

[0183] • When moving due to tidal currents / wind changes to allow the CTV to "follow the wind" around the OWT, or automatically follow the CTV as it moves around the charging area.

[0184] Provide umbilical cable side load protection.

[0185] In order to achieve these three functions, the slewing and sliding system has two working modes. Fig.25 The operating mode of each step in the charging process is shown.

[0186]

[0187] Table 3

[0188] Fig.25 The recommended slip / slew control mode for each step is shown, but the CTV crew is always able to select the control mode, for example when the vessel is moving to the charging area or returning to the OWT, the crew can engage slip / slew control in speed mode with the CTV controlling the umbilical catenary.

[0189] The slide may have two configurations depending on whether the system will be installed on an existing OWT (in which case no platform modification is possible) or on a new OWT (in which case platform modification is more flexible).

[0190] Connection Order

[0191]

[0192] Table 4

[0193] Ship bell mouth working mode:

[0194] The ship bell mouth of Centella asiatica station has two working modes. Fig.26 The operating mode of each step in the charging process is shown.

[0195]

[0196] Table 5

[0197] Charging Mode

[0198] The marine charging system of the present invention can be used in two different modes:

[0199] · Directly connect to CTV battery.

[0200] Supply DC energy to the ship's common DC system.

[0201] Fig.31(a) and (b) show two charging methods. When the charging system is connected directly to the battery, the DC-DC converter in the charger is responsible for following the battery charging pattern, for which the charger must communicate with the battery BMS. When the charging system is connected to the ship's public DC bus, the charger only provides DC supply, and the DC-DC converter as part of the ship's system controls the battery charging. In this case, the charger also needs to communicate with the BMS to understand the battery's charge status. Both charging methods have their own advantages and disadvantages, and the Centella station is able to provide all the functions and electrical protection required for both.

[0202] The system is designed to provide DC power at a voltage compatible with the ship's electrical and propulsion systems and can be configured to cover the necessary common DC bus and battery voltage ranges common on this type of vessel. In addition, for high power, the umbilical cable and connector will be equipped with a water cooling system.

[0203] Ship and OWT control systems

[0204] The vessel and OWT have two independent and self-sufficient control systems, allowing the vessel and OWT to always have full control of their respective sides, regardless of whether there is a communication link between the vessel and the OWT. This allows the umbilical cable, connectors, vessel, batteries and winders to be protected at all times.

[0205] A redundant wireless link is implemented between the vessel and the OWT. Each vessel control system has a unique identifier, allowing the OWT to identify and authenticate the vessel it is connected to and provide winder and charger control only to authenticated vessels. Fig.28 A simplified representation of the wireless link between the vessel and the OWT is shown.

[0206]

[0207] Table 6 Ship operator interface control system

[0208]

[0209] Table 7

[0210] Booking, wind farm and vessel operator applications

[0211] Above the OWT, vessel and wind farm control systems is the MJR Application Cloud, which is the user portal for the process. The vessel will always be in communication with the cloud using a 4G link, while the wind farm and OWT will likely be connected via an array cable fiber optic infrastructure, using 4G when fiber is not available. Fig.30 A simplified representation of the MJR cloud architecture is shown.

[0212]

[0213]

[0214] Table 8

[0215] Fig.29 / Not shown in Table 8 is the Vessel Operator App which is also linked to the MJR App Cloud and whose function is to display vessel information to the vessel operator such as completed charging processes, battery levels, analytics, billing information and all other useful metrics and data. Fig.30 Shows from Figure 23 to Figure 25 The communication flow from step 1 to step 6 of the flow board.

[0216] In addition, Fig.30 In the figure, the solid lines represent messages sent to the MJR Application Cloud, and the dotted lines represent messages from the MJR Application Cloud to one of the systems.

[0217] Data logger / database

[0218] A data logger / database is provided in the MJR Application Cloud, which continuously records relevant data from chargers, wind farms and CTVs. The data logger provides analytical data to wind farm and vessel operators, allowing them to access a large number of data sets, such as the following:

[0219]

[0220] Table 9

[0221] Umbilical cable protection The umbilical is always protected against excessive tension and side loads which could damage the umbilical itself or compromise the integrity of the reel, OWT or CTV. In automatic mode the system also monitors and controls umbilical slack.

[0222] Active compensation:

[0223] The active compensation system depends on the availability of electrical power and the winder control system, drum drive motor and variable speed drive being fully operational.

[0224] Drum motor:

[0225] When the catenary control is in following or mooring mode, the drum motor actively keeps the umbilical cable tension within limits, assisting the passive compensation system if required. To monitor the tension, the control system uses the load cell and the stroke and pressure of the passive compensation cylinder as feedback.

[0226] Electrical protection

[0227] The electrical protection of the system is provided on both the charging side (OWT) and the ship side (CTV), and its design complies with the electrical installation requirements of DNVGL-RU-SHIP Part 4 Chapter 8, as shown below:

[0228] Charger AC feeder:

[0229]

[0230] Table 10

[0231] Charger DC output

[0232]

[0233] Table 11

[0234] Connector System

[0235]

[0236] Table 12

[0237]

[0238] Table 13

[0239] Failure Mode Overview

[0240] During the system design process, a separate FMECA has been developed to inform the design and ensure that any high severity failure modes are adequately mitigated.

[0241] Therefore, it is always possible to:

[0242] Disconnect and release the CTV from the system in an emergency

[0243] Protects umbilicals, connectors, CTVs, winders and OWTs from mechanical overloads using passive compensation and passive release principles

[0244] Electrical protection of umbilicals, connectors, CTVs, reels and OWTs with approved hardware protection devices

[0245] Ship booking system interface

[0246] Figures 32(a) to (c) show screenshots of the ship application home screen, where the CTV crew can see the location and real-time status of all nearby chargers. Figure 32(b) shows a screenshot of the ship application booking screen. Figure 32(c) shows a screenshot of the ship application chat screen, through which the CTV crew conducts an online chat with the wind farm operator.

[0247] Wind Farm Software Interface (OWT)

[0248] Figures 32(d) to (f) show screenshots of the main screen of the wind farm application, where the wind farm control room operator can see the location and status of all CTVs close to the charger. Figure 32(e) shows a screenshot of the booking schedule of the wind farm application, where the wind farm operator can see all scheduled bookings. Figure 32(f) shows a screenshot of the status of the Centella asiatica station of the wind farm application.

Claims

1. An adaptive tension compensator system for offshore charging of a vessel (12) via an umbilical cable (14) of a motor-driven reel (16) disposed at a power station (10), the system comprising: a motor hub member (102) mountable to the motor shaft (20) and configured to transmit rotational motion between the motor (18) and the winding drum (16) along a first rotational axis (104); a winding hub member (106) mountable to the winding drum, coaxially disposed with the motor hub member, and configured to transmit rotational motion between the winding drum and the motor; A coupling mechanism (108) is operatively coupled between the winding hub member and the motor hub member, adapted to transmit rotational motion between the winding hub member and the motor hub member when the motor is in a first mode, and adapted to provide offset rotational motion of the winding hub member about the first rotational axis between a first angular position (110) and a second angular position (112) relative to the motor hub member when the motor is in a second mode.

2. The adaptive tension compensator system of claim 1, wherein: The coupling mechanism includes a first elastic energy storage system (114) adapted to elastically resiliently bias the winding hub member toward the first angular position.

3. The adaptive tension compensator system of claim 2, wherein: The first elastic energy storage system includes at least one first accumulator (116) configured to provide a predetermined one-way spring force in response to rotational movement of the winding hub member relative to the motor hub member from the first angular position toward the second angular position.

4. The adaptive tension compensator system of claim 3, wherein: The first accumulator is any one of a piston accumulator, a diaphragm accumulator, a bladder accumulator, a spring accumulator and a gas-charged accumulator.

5. The adaptive tension compensator system according to any one of claims 3 and 4, wherein: The first elastic energy storage system comprises at least two diametrically opposed first accumulators, each accumulator being adapted to provide the predetermined unidirectional spring force in synchronism with the other accumulator.

6. The adaptive tension compensator system according to any one of claims 3 to 5, wherein: The at least one first accumulator is operatively coupled to a hydraulic cylinder or a pneumatic cylinder (118).

7. An adaptive tension compensator system according to any one of the preceding claims, wherein: When the motor is in said first mode, the motor shaft is actively or passively rotatable, and wherein when the motor is in said second mode, the motor shaft is rotationally locked.

8. An adaptive tension compensator system according to any of the preceding claims, further comprising a gear mechanism (120) operatively connected between the motor shaft and the winding hub member and adapted to provide a predetermined transmission ratio between the motor shaft and the winding drum.

9. The adaptive tension compensator system of claim 8, wherein: The gear mechanism is a planetary gear mechanism.

10. The adaptive tension compensator system according to any of the preceding claims, further comprising a stopper assembly (122) adapted to stop the rotational movement of the winding hub member at the second angular position relative to the motor hub member.

11. The adaptive tension compensator system of claim 10, wherein: The stopper assembly includes a contact element (124) coupled to the winding hub member, and a surface element (126) coupled to the motor hub member, the surface element being adapted to stopably engage the contact element when the winding hub member is rotationally moved to the second angular position relative to the motor hub member.

12. An adaptive tension compensator system according to any of the preceding claims, comprising a cable suspension mechanism (200) configured to guide and suspend an umbilical cable of a winding drum, the cable suspension mechanism comprising a suspension arm (202) operatively connected to a support frame (22) of a motor-driven winding drum and configured to move in an offset manner between an upper arm position (204) and a lower arm position (206) about a pivot axis (208) arranged parallel to the rotation axis.

13. The adaptive tension compensator system of claim 12, wherein: The cable suspension mechanism includes a second elastic energy storage system (208) adapted to elastically resiliently bias the suspension arm toward the lower arm position.

14. The adaptive tension compensator system of claim 13, wherein: The second elastic energy storage system includes at least one second accumulator (210) configured to provide a second one-way spring force in response to pivotal rotation of the suspension arm about the pivot axis.

15. An adaptive tension compensator system according to any of the preceding claims, further comprising a slewing mechanism (300) operatively mounted between the power station and the motor-driven winding drum and configured to allow the motor-driven winding drum to rotate about a second rotation axis (308) perpendicular to the first rotation axis (104).

16. An adaptive tension compensator system according to any of the preceding claims, further comprising a sliding mechanism (400) operatively mounted between the power station and the motor-driven winding drum and configured to allow the motor-driven winding drum to move relative to the power station along a predetermined track (402).

17. An adaptive tension compensator system according to any of the preceding claims, further comprising a cable connector (500) which can be mounted to a vessel (12) and is suitable for receiving and locking an end portion (24) of an umbilical cable (14) of a motor-driven winding drum and providing a predetermined range of movement of the received umbilical cable.

18. The adaptive tension compensator system of claim 17, wherein: The cable connector includes a dual-axis gimbal mechanism (502) adapted to allow the cable connector to rotationally move about a first gimbal axis (504) and a second gimbal axis (506) perpendicular to the first gimbal axis.

19. The adaptive tension compensator system of claim 18, wherein: The gimbal mechanism is adapted to actively and / or passively move the cable connector.

20. An adaptive tension compensator system according to any one of claims 17 to 19, wherein: The cable connector includes a flare member (508) adapted to guidingly receive an end portion of an umbilical cable.

21. An adaptive tension compensator system according to any one of claims 17 to 20, wherein: The cable connector includes a docking mechanism (510) adapted to mechanically and electrically connect with an end portion of an umbilical cable.

22. The adaptive tension compensator system of claim 21, wherein: The docking mechanism is adapted to be disconnected from the end portion of the umbilical cable under a predetermined pulling force acting on the umbilical cable.

Images