Patent Publication Number: US-2022239151-A1

Title: Marine vessel with repositionable onboard inductive charge system for recharging an onboard rechargeable energy source when servicing offshore wind turbines

Description:
RELATED APPLICATION 
     This Application claims priority to co-pending U.S. Provisional Patent Application having Ser. No. 63/121,130 filed on Dec. 3, 2020; the contents of which are incorporated herein by reference in their entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     Offshore wind turbines require maintenance to ensure proper upkeep and operation. To service the offshore wind turbines, marine vessels may be used to travel between the wind turbines. As understood in the art, marine vessels that service offshore wind turbines are sufficiently large to be able to support a crew and needed equipment to service the offshore wind turbines. Such large marine vessels have propulsion systems that are typically powered by diesel fuel. As the marine vessels typically remain at the wind turbines being serviced, the marine vessels must remain powered to ensure that the marine vessels do not collide with the platform or support structure on which the offshore wind turbines are secured. As a result, fuel consumption while servicing offshore wind turbines can be expensive and produce a significant amount of emissions. 
     SUMMARY OF THE INVENTION 
     To overcome the problem of marine vessels consuming excessive diesel fuel while being used during offshore wind turbine maintenance, electric-powered marine vessels with rechargeable energy sources may be used. In an embodiment, some or all of the wind turbines may be configured to collect and transfer power to the marine vessels via wireless electrical transfer devices, such as an inductive chargers, positioned at the platforms. In an embodiment, the marine vessels may be configured with corresponding wireless electrical transfer devices, so as to receive power for use in recharging the rechargeable energy sources on the marine vessels. 
     One embodiment of a marine vessel may include a propulsion system and a rechargeable energy storage system inclusive of at least one rechargeable energy source configured to supply power to the propulsion system. The marine vessel may further include a vessel-side inductive charge component in electrical communication with the rechargeable energy storage system, and be configured to inductively couple with a platform-side inductive charge component positioned at a marine-based platform, the platform-side inductive charge component electrically coupled to a power generator at the marine-based platform that generates electrical power to be electrically and wirelessly conducted via the corresponding inductive charge component to the inductive charge component. A moveable structure may be coupled to the marine vessel on which the vessel-side inductive charge component is positioned to enable the moveable structure to be moveably positioned to wirelessly couple the vessel-side inductive charge component with the platform-side charge component that is positioned at the marine-based platform, thereby causing the rechargeable energy storage device to be recharged. The moveable structure may be dynamically controlled to maintain relative position between the vessel-side and platform-side and platform-side inductive charge components. 
     A method of recharging a rechargeable storage source on a marine vessel may include positioning the marine vessel at a platform. A structure coupled to the marine vessel on which a vessel-side inductive charge component is positioned may be moved to enable the structure to be moveably positioned to wirelessly couple the vessel-side inductive charge component with the platform-side charge component that is positioned at the marine-based platform. A rechargeable energy source on the marine vessel may be recharged by conducting electrical power signals via the platform-side inductive charge component and vessel-side inductive charge component. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Illustrative embodiments of the present invention are described in detail below with reference to the attached drawing figures, which are incorporated by reference herein and wherein: 
         FIG. 1  is an illustration of an illustrative offshore wind turbine farm including a set of offshore wind turbines with respective platform-side inductive charge components and a marine vessel configured with a rechargeable energy source system with a vessel-side inductive charge component; 
         FIG. 2  is an illustration of an illustrative scene in which a marine vessel is recharging a rechargeable energy source using inductive charging from a marine platform, in this case an offshore wind turbine; 
         FIG. 3  is an illustration of an illustrative marine vessel showing system components including a rechargeable energy storage system for powering the marine vessel; and 
         FIG. 4  is a flow diagram of an illustrative process for recharging a marine vessel from an offshore platform, such as an offshore wind turbine. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     With regard to  FIG. 1 , an illustration of an illustrative offshore wind turbine farm  100  including a set of offshore wind turbines  102   a - 102   n  (collectively  102 ) mounted to platforms  104   a - 104   n  (collectively  104 ) with platform-side inductive charge components (see  FIG. 2 ) and a marine vessel  106  configured with a rechargeable energy source system (see  FIG. 3 ) with a vessel-side inductive charge component (see  FIG. 3 ) is shown. The marine vessel  106  may be used to service each of the wind turbines  102  using a fully electric propulsion system and be capable of recharging at some or all of the wind turbines, as further described herein. By including an inductive charge component that is repositionable on the marine vessel  106 , such as positioning the inductive charge component on a bottom of a gangplank (see  FIG. 2 ) or carried by a crane, for example, cost may be reduced for the platforms  104  as a single moveable component (i.e., on the marine vessel  106 ) may be utilized rather than multiple moveable components (i.e., moveable components on multiple or all platforms  104 ). In other words, the inductive charge component on the platform(s) may in a fixed position and the vessel side-inductive charge component may be moveable, and optionally dynamically controlled to be maintained in a stable position (i.e., in a fixed position within a physical distance tolerance, such as  3 -inches). Although a wireless solution, such as an inductive charge system, is ideal, it should be understood that other wired or plug solutions on moveable structures may be possible, as well. 
     With regard to  FIG. 2 , an illustration of an illustrative scene  200  in which a marine vessel is recharging a rechargeable energy source using inductive charging from a marine platform, in this case an offshore wind turbine, is shown. The scene  200  may include a wind turbine  202  affixed to a marine platform  204 . A marine vessel  206  may be configured to engage with the platform  204  using a gangplank or crane  208 . Mounted beneath the gangplank  208  may be a vessel-side inductive charger component  210  that may engage a platform-side inductive charger component  212  positioned on or extending from the platform  204 . For example, an extension member  214  may be coupled to the platform  204  and have a platform-based inductive component mounted thereon. In an embodiment, the platform-based inductive component  212  may be positioned facing upward, thereby enabling the vessel-side inductive charger component  210  mounted beneath the gangplank or crane  208  to be positioned above the upward facing platform-based inductive component  212 . It should be understood that the platform-based inductive charger component  212  and/or vessel-side inductive charger component  210  may have different orientations, such as being horizontally aligned with one another or otherwise. It should be understood that the platform-based inductive charger component  212  may have a power system that is connected to an output of the wind turbine  202  or any other power source to draw energy therefrom to supply the platform-based inductive charger component  212 . 
     In an embodiment, charge storage elements (see  FIG. 3 ) may be positioned on the platform  204 , thereby storing a charge that may be drawn by the rechargeable energy storage system even if the wind turbine  202  is not operational while the marine vessel  206  is positioned thereat. By having the platform-based inductive charger component  212  stationary relative to the vessel-based inductive charger component  210 , an operator of the marine vessel  206  may focus on maintaining position of the vessel-based inductive charger component  210  relative to the platform-based inductive charger component  212 . In an embodiment, an extension member  214  on which the platform-based inductive charger component  212  may be fixed position relative to the platform. In an embodiment, the extension member  214  may have the ability to be moved so as to maintain a relative position between the extension member  214  and gangplank  208 . Similarly, the gangplank  208  may have a controller that may be used to dynamically adjust position of the gangplank  208  so as to maintain the vessel-based inductive charge component  210  in a stable position relative to the platform-based inductive charger component  212  in case of movement of the marine vessel  206  relative to the platform  204  due to waves, wind, or current, for example. 
     With regard to  FIG. 3 , an illustration of an illustrative marine vessel  300  showing system components including a rechargeable energy storage system  302  for powering the marine vessel is shown. The rechargeable energy storage system  302  may include one or more rechargeable energy storage sources  304  that may be recharged and used to power electrically driven systems and devices onboard the marine vessel  300 . As shown, the marine vessel  300  may further include a control computer  306  for controlling operation of the marine vessel  300 , including navigation using an inertial measurement unit, propulsion, communications, scheduling, and so forth, as understood in the art. The control computer  306  may be controlled by an operator computer  308  or a remote computer (not shown), such as a land-based computer or cloud computer. The control computer  306  may further be in electrical communication with a propulsion system  310  that may include engines or thrusters  312   a - 312   n  (collectively  312 ) that drive propellers  314  or other propulsion mechanism. Depending on the configuration of the marine vessel  300 , the thrusters  312  may be powered by diesel fuel or electricity. In an embodiment, one or more of the thrusters  312  may be diesel driven and one or more thrusters may be electricity driven. An inertial measurement unit (IMU)  316  may produce inertial measurements, including global positioning be used by the control computer  306  for maintaining navigation headings and speed, but also stable or fixed positions when positioned at a platform, for example. The IMU  316  may measure parameters, such as pitch, roll, longitude, latitude, and speed vectors, and may measure absolute and/or relative positions. 
     In an embodiment, all of the thrusters  312  may be electricity driven. Still yet, the thrusters  312  may be of different sizes and oriented in different directions for forward, side-to-side, and reverse movement. As the marine vessel  300  may be used for working near platforms, such as offshore wind turbines (see  FIG. 1 ), the use of thrusters  312  that are partial or all electric thrusters allows for the rechargeable energy storage system  302  to power the marine vessel  300  partially or entirely using renewable energy sources (e.g., wind turbine, solar cells, etc.) accessible at the offshore wind turbine platforms, as described herein. 
     The marine vessel  300  may further include a gangplank recharger interface system  318  that may control operation of a gangplank unit  320  including a gangplank  322  on which a vessel-side inductive charge component  324  is connected. A power line  326  may be electrically connected to the vessel-side inductive charge component  324  and rechargeable energy storage system  302  directly or via the gangplank recharger interface system  318 . The power line  326  may carry electrical power  328  delivered to the vessel-side inductive charge component  324  by a platform-side inductive charge component  330  at a platform  332 , which may be an offshore wind turbine. It should be understood that rather than the vessel-side inductive charge component  324  be connected to a gangplank  322 , that the vessel-side inductive charge component  324  may be connected to a crane or other moveable structure that allows for the vessel-side inductive charge component  324  to be repositioned at a platform or land-side inductive charger component (i.e., inductive charge component located at a pier, for example). 
     To supply power between the platform-side inductive charge component  330  and vessel-side inductive charge component  330 , a power collector system  334  connected to a structure, in this case a vertical structure, but any structure and in any orientation available to support the power collector system  334  is possible. The platform  332  may further include one or more energy storage sources  338   a - 338   n  (collectively  338 ) that may be charged by the power manager system  334 . The power collector system  334  may be electrically coupled to power sources, such as a wind turbine mounted to the platform  332 , solar cells at the platform  332 , or otherwise, and the energy storage sources  338  via power lines  340   a - 340   n  (collectively  340 ). Electrical power  342   a - 342   n  (collectively  342 ) may be communicated by the power collector system  334  via power lines  340   a - 340   n  (collectively  340 ) to be stored by the energy storage sources  338 . 
     In operation, the marine vessel  300  may be positioned at the platform  332  so as to rechargeable energy storage system  304  to charge the energy storage sources  304 . More specifically, the gangplank recharger interface system  318  may control electromechanical components, such as one or more motors, to reposition the gangplank system  320  from a first position (e.g., raised or retracted) to a second position (e.g., lowered or extended) so that the vessel-side inductive charge component  324  may be positioned within an inductive range of the platform-side inductive charge component  330 . Power signals  344   a  may be inductively transferred from the power collector system  334  and/or energy storage sources  338  via the platform-side inductive charge component  330  and vessel-side inductive charge component  324  so as to be power signal  344   b . The power signal  344   b  may be conducted along the power line  326  and used to charge the energy storage sources  304 . 
     In particular, a frequency converter (not shown) may be used to transform the 50/60 Hz, 3-phase system into the power signal  344   a  with an AC voltage signal at several kHz. This voltage feeds the component  330 , while the component  324  receives the power signal  344   b  and conducts the signal  344   b  to the gangplank recharger interface system  318 . power signal  344   a . The high frequency voltage may then be converted to DC-voltage by the gangplank recharger interface system  318  or alternatively the rechargeable energy storage system  302  to recharge the rechargeable energy storage source(s)  304 . In an embodiment, this system is capable of transferring more than 2 MW of energy between the components inductive charge components  330  and  324  within a distance range of between 150 and 500 mm. Other configurations of power conversion are also possible. 
     To maintain the platform-side inductive charge component  330  and vessel-side inductive charge component  324  in inductive proximity from one another, the control computer  306  of the marine vessel  300  may be placed into a “bumper” mode so as to maintain a highly stable position of the marine vessel  300  due to being attached to the platform  332  via lines with bumpers disposed between the marine vessel  300  and the platform  332 . The gangplank  332 , which is typically maintained in position on the platform  332 , enables the charge components  324  and  330  to remain in inductive position relative to one another. Housings of the charge components  324  and  330  may be sufficiently durable to avoid damage such as when the two housings touch or contact one another while maintaining electrical conductors (e.g., coils) within the housings inductively coupled with one another. The control computer  306  may be configured to monitor the power signal  344   b , and if the power signal  344   b  stops or is significantly reduced while the charge components  324  and  330  are supposed to be inductively coupled, the control computer  306  may issue a notification to the operator computer  308 , which may display and/or communicate a notice to an operator that a power transfer disruption has occurred. 
     In an embodiment, if the marine vessel  300  is to remain floating, a stable location (e.g., within 2 feet) of the marine vessel  300  may be maintained, and the gangplank recharger interface system  318  may be set to maintain a stable position of the gangplank system  320  so that the vessel-side inductive charger  324  remains in inductive coupling with the platform-side inductive charger  330 . For example, a 3-degree-of-freedom controller may maintain the vessel-side inductive charge component  324  in a fixed point in space by controlling X, Y, and Z axes of the gangplank system  320  optionally using a local IMU or other measuring device(s) on the gangplank  322  or motors controlling the gangplank  322 , for example. In an embodiment, the platform-side inductive charge component  330  may be positioned on a 3-axes electromechanical system (not shown) that allows for the platform-side inductive charge component  330  to be moved relative to the vessel-side inductive charge component  324 , thereby providing additional inductive charging stability between the two components  324  and  330 . 
     A variety of other mechanical and electromechanical techniques for maintaining the platform-side inductive charge component  330  and vessel-side inductive charge component  324  in inductive proximity from one another may be used. In an embodiment, a power level may be monitored, and if the power level drops off, then the gangplank recharger interface system  318  may reposition the gangplank system  320 . The power level being monitored may be the power signal  344   b , for example. Still yet, electromagnetic sensing, optical sensing, or a combination thereof may be utilized. Still yet, other non-powered relative stability structures may be utilized, such as using springs or coils, dampers, universal joints, etc., to assist in maintaining the components  330  and  324  inductively coupled with one another. In another embodiment, a mechanical temporary locking system may be utilized, but the locking system may release when a certain amount of force is exerted on the locking system, thereby preventing the gangplank  322  or other structural component from being damaged. 
     With regard to  FIG. 4 , a flow diagram of an illustrative process  400  for recharging a marine vessel from an offshore platform, such as an offshore wind turbine, is shown. The process  400  may start at step  402 , where a marine vessel may be positioned at a platform, such as an offshore wind turbine, offshore oil platform, docket, or otherwise. In being positioned, a controller computer that controls a propulsion system of the marine vessel may be placed in a stationary hold mode, whereby the marine vessel maintains a stationary position (e.g., within 2 feet). At step  404 , a vessel-side inductive charge component may be positioned in an inductive relation with a platform-side inductive charge component. To be in an inductive relation, an inductive charge between the platform-side inductive charge component and vessel-side inductive charge component, and such a relative position may depend on a variety of electromagnetic factors of the inductive charge components. The position of the inductive charge components may be maintained in relative position from one another using a variety of techniques, as described relative to  FIG. 3  hereinabove. At step  406 , rechargeable energy source(s) on the marine vessel may be recharged by conducting electrical power signals via the platform-side inductive charge component and vessel-side inductive charge component. The recharging may be performed until the rechargeable energy source(s) are fully recharged. 
     As a result of using a repositionable vessel-side inductive charge component to be positioned in an inductive relation to one another, an increased charging time may result. For example, by having the vessel-side inductive charge component mounted to an underside or other location on the gangplank that is going be moved into a bumper position when the marine vessel is positioned at a pier or platform, charging may start when the vessel-side inductive charge component or onboard coil is positioned 500 mm away from the platform-side inductive charge component or onshore coil. That is, the typically takes needed to connect the marine vessel to a plug-in charger is eliminated, and charging may be initiated immediately upon moving the gangplank into position. The increased time allows more kWhs to be transferred to the battery during mooring. 
     The previous description is of at least one embodiment for implementing the invention, and the scope of the invention should not necessarily be limited by this description. The scope of the present invention is instead defined by the following claims.