Offshore floating type gravity energy storage system and method based on gravity energy storage

Abstract

The invention discloses an offshore floating type gravity energy storage system and method based on gravity energy storage, the system comprises a large floating body, the large floating body is connected with a seabed anchorage through a main rope, and the large floating body floats in a specific area on the sea surface; a lifting device and a power generation device are arranged on the large floating body, the lifting device is connected with a heavy object and the main frame through ropes, power is generated through the power generation device in the process that the heavy object descends to the seabed, and the heavy object is lifted to the large floating body for gravity energy storage; the main frame can frame a plurality of heavy objects for limiting, and each heavy object and the main frame can ascend and descend through a rope connected with the heavy object and the main frame. According to the invention, the ropes or auxiliary cables for lifting the weights can be prevented from being mutually entangled, each floating body can lift a plurality of weights at the same time without mutual interference because the ropes are prevented from being mutually entangled, the charging and discharging power can be greatly increased, and the water surface utilization rate can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of offshore gravity energy storage, and particularly relates to an offshore floating gravity energy storage system and method based on gravity energy storage. Background Art

[0002] The demands of electric vehicles and artificial intelligence may lead to a significant increase in electricity demand. Since both wind and sunlight are unstable, neither photovoltaic nor wind power can provide stable power generation capabilities. For the stability of the power grid, large-scale energy storage power stations are needed to store the electricity generated by wind power and photovoltaics. Pumped-storage power stations and compressed air energy storage are mature and reliable technologies. However, only specific topographical or geological conditions meet the requirements, and their energy conversion rates are not high. The ideal goal should be that the cost of photovoltaics or wind power plus the cost of energy storage is not higher than the cost of coal-fired power. Therefore, it is necessary to develop other large-scale energy storage technologies that are cheap, reliable, can be built quickly, and have high energy conversion rates.

[0003] Deep-sea gravity energy storage has the potential to become a competitive large-scale energy storage technology. In the prior art, Chinese invention patent CN103867409B discloses a gravity energy storage system using the depth difference of the ocean. Multiple sets of power lifting devices are arranged to lift heavy objects onto a large floating body for energy storage. Since the heavy objects are suspended on cables by hooks for ascending and descending, when multiple sets of power lifting devices are set, multiple cables respectively suspend the corresponding heavy objects, and there may be complex and unstable ocean currents below the sea surface. When multiple heavy objects operate within a relatively short horizontal distance, the unstable ocean currents may cause various ropes to become entangled with each other, thereby affecting the use of the energy storage platform. Summary of the Invention

[0004] Aiming at the problems existing in the prior art, the present invention provides an offshore floating gravity energy storage system and method based on gravity energy storage, which solves the problem that when the underwater ocean current is unstable, the ropes connecting multiple floating bodies below the large floating body to the heavy objects or the hooks of the heavy objects may become entangled with each other.

[0005] The technical solution of the present invention is as follows:

[0006] In the first aspect of the present invention, an offshore floating gravity energy storage system based on gravity energy storage is provided, including a large floating body. A lifting device and a power generation device are arranged on the large floating body. The lifting device is respectively connected to a heavy object and a main frame through ropes. When the heavy object descends to the seabed, power generation is carried out through the power generation device, and when the heavy object is lifted to the large floating body, gravity energy storage is carried out; the main frame can limit the heavy objects in the horizontal direction, and the heavy objects and the main frame can respectively ascend and descend through the ropes connected thereto.

[0007] In some embodiments of the present invention, the lifting device employs a winch, a capstan or a crane. Multiple winches are provided, and each winch is connected to a heavy object by a rope. One or more groups of winches are provided on each floating body. Each group of winches includes multiple winches, and multiple heavy objects are connected by ropes under each group of winches.

[0008] Each group of winches also corresponds to a main frame, and each main frame also has a winch and a rope to control its lifting; the multiple heavy objects under each group of winches are limited by a main frame.

[0009] In some embodiments of the present invention, the main frame includes upper and lower planar layers. Multiple rope limiting spaces are provided on the upper planar layer of the main frame to limit the horizontal position of the rope or cable above the heavy object, and the lower planar layer of the main frame is used to enclose a group of heavy objects.

[0010] Further, sensors and propellers are provided on the upper layer of the main frame; the propellers are used to adjust and control the horizontal position and rotation of the main frame.

[0011] In some embodiments of the present invention, the large floating body is connected to an anchor on the seabed by a main rope, the length of the main rope can be adjusted, and the large floating body floats in a specific area on the sea surface.

[0012] In some embodiments of the present invention, storage hooks are provided at the bottom of the large floating body, and heavy objects are hung on the storage hooks for gravitational energy storage. Multiple suspended heavy objects are connected by ropes or rigid rods.

[0013] In some embodiments of the present invention, the main frame is connected to a sub-frame, the sub-frame is sleeved on the main rope, and the main frame and the sub-frame are lifted along the main rope.

[0014] The sub-frame is connected to the upper layer of the main frame; or, the lower layer of the main frame; or, the upper and lower layers of the main frame are respectively connected to the sub-frame.

[0015] The main frame and the sub-frame are connected by rigid connecting rods and / or ropes. When connected by ropes, the length of the ropes can be adjusted.

[0016] In some embodiments of the present invention, multiple sub-frames are sleeved on the main rope. The sub-frame adopts a frame that can be opened and closed. A variety of sensors are provided on the sub-frame. The sub-frame is driven by a motor to open and close, and the sub-frame is locked and unlocked with the main rope.

[0017] In some embodiments of the present invention, during the ascending or descending process of the main frame, the auxiliary frame moves along the main rope, and the movement of the main frame and the auxiliary frame is guided by the main rope. When two auxiliary frames on the main rope approach and need to pass each other, one of the auxiliary frames crosses over the other frame and then reframes the main rope.

[0018] In some embodiments of the present invention, a large frame is suspended below the large floating body by a winch and a rope to frame and separate all the ropes and cables belonging to two adjacent main frames in the horizontal direction, so as to prevent these two groups of ropes and cables from winding around each other. The large frame is located above two adjacent main frames in the horizontal direction in the vertical direction, and the depth of the large frame can be adjusted by the length of its suspension rope.

[0019] In a second aspect of the present invention, there is provided a working method of an offshore floating gravity energy storage system based on gravity energy storage, including:

[0020] When energy storage is required, after lifting a heavy object by a lifting device, the heavy object is suspended at the bottom of the floating body platform for gravity energy storage;

[0021] When power generation is required, the heavy object at the bottom of the floating body platform is gradually sunk into the seabed, and the power generation device uses the gravity and potential energy of the heavy object to generate electricity;

[0022] During the ascending or descending process of the heavy object, the main frame frames the heavy object and its affiliated ropes and rises or falls synchronously with the heavy object, and the main frame limits the heavy object and the ropes suspending the heavy object in the horizontal direction to avoid entanglement between the ropes.

[0023] One or more technical solutions of the present invention have the following beneficial effects:

[0024] (1) For the offshore floating gravity energy storage system based on gravity energy storage provided by the present invention, by setting the main frame to limit various ropes and cables belonging to it in the horizontal direction, it is possible to avoid the mutual entanglement between various ropes and cables within the same main frame. By using a large frame to frame the ropes and cables belonging to adjacent main frames under the same floating body, it is possible to prevent the mutual winding between the ropes belonging to different main frames under the same floating body. Therefore, when there is an unstable ocean current underwater, it is possible to avoid the mutual entanglement of the ropes or auxiliary cables under the same floating body. Due to avoiding the mutual entanglement of the ropes, each floating body can lift multiple heavy objects or multiple groups of heavy objects simultaneously without interference with each other, which can greatly increase the charge-discharge power.

[0025] Furthermore, since many heavy objects can be lifted simultaneously and power is no longer a limiting factor, the speed of lifting and lowering the heavy objects does not need to be too fast, which can reduce the resistance of water to the lifted and lowered heavy objects, thereby reducing energy loss.

[0026] (2) The offshore floating gravity energy storage system based on gravity energy storage provided by the present invention connects the main frame and the auxiliary frame, sleeving the auxiliary frame on the main rope, and using the main rope connecting the floating body and the anchor to provide a guiding function for the up and down movement of the main frame and the auxiliary frame, which can prevent the ropes belonging to two floating bodies in a short distance from being wound around each other. In this way, the floating bodies can be placed closer to each other without worrying about the entanglement of their ropes, which can improve the utilization rate of the unit water surface, that is, more floating bodies can be placed within a certain water area to store more energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 is a schematic diagram of the offshore floating gravity energy storage system based on gravity energy storage of the present invention;

[0028] Figure 2 is a side view of the main frame of the present invention;

[0029] Figure 3 is a top view of the main frame of the present invention;

[0030] Figure 4 is a bottom view of the main frame of the present invention;

[0031] Figure 5 is a schematic diagram of the passing process of the auxiliary frame on the main rope of the present invention;

[0032] Figure 6 is a schematic diagram of the opening and closing of the auxiliary frame on the main rope of the present invention.

[0033] In the figure: 1. Large floating body; 2. Hoisting unit; 3. Main frame; 301. Upper plane layer; 3011. Rope frame; 3012. Cable frame; 3013. Sensor and propeller; 302. Lower plane layer; 4. Main rope; 5. Hovering main frame; 6. Rope; 601. Rope connecting the main frame; 602. Rope connecting the heavy object; 7. Auxiliary cable; 8. Heavy object; 9. Rope for hanging the heavy object; 10. Winch; 11. Connector; 12. Pulley; 13. Submarine heavy object; 14. Anchor; 15. Hook; 16. Anchor with sonar beacon; 17. Auxiliary frame; 18. Connecting link; 19. Lights and cameras; 20. Rod; 21. Large frame; 22. Rope connecting the large frame. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0034] The present invention will be further described below in conjunction with the drawings and embodiments.

[0035] Embodiment 1

[0036] In a typical embodiment of the present invention, an offshore floating gravity energy storage system based on gravity energy storage is proposed, as Figure 1As shown, it includes a large floating body 1, and the large floating body 1 is connected to an anchor 14 on the seabed through a main rope 4. The large floating body 1 floats in a specific area on the sea surface;

[0037] An elevating device and a power generation device are provided on the large floating body 1. The elevating device is respectively connected to a heavy object 8 and a main frame 3 through ropes. When the heavy object descends to the seabed, power is generated through the power generation device, and when the heavy object is lifted to the large floating body, gravitational energy storage is performed; the main frame can frame multiple heavy objects for horizontal limiting. The heavy object and the main frame can be respectively lifted and lowered through the ropes connected to them, but usually they are lifted and lowered together. Specifically, the main frame is connected through a rope 601 connecting the main frame, and the heavy object 8 is connected through a hook 15 on a rope 602 connecting the heavy object.

[0038] In this embodiment, the elevating device adopts a winch unit 2. Multiple groups of winch units 2 can be provided, and each group includes multiple winches. Each winch suspends a heavy object through a rope, and multiple winches in a group lift and lower multiple heavy objects in a coordinated manner simultaneously.

[0039] Furthermore, each group of winch units 2 corresponds to a main frame 3, and the main frame 3 limits multiple heavy objects on each winch unit 2. The main frame 3 usually rises and falls synchronously with the corresponding heavy object or heavy object hook below it.

[0040] As Figure 3 and Figure 4 shown, the main frame 3 includes upper and lower planar layers. Among them, multiple rope limiting spaces are provided on the upper planar layer 301 of the main frame 3, and the lower planar layer 302 of the main frame 3 is a large limiting space that frames the heavy objects, and the lower planar layer 302 can prevent other ropes from entangling the heavy objects. Specifically, a rope frame 3011 and a cable frame 3012 are provided on the upper planar layer 301 to respectively limit the ropes connecting the heavy objects and the auxiliary cable 7, so that each rope can only be located within an independent and limited interval in the horizontal direction and cannot be entangled with each other. The upper planar layer also frames the auxiliary cable, and the auxiliary cable is responsible for transmitting power and signals. Sensors and a propeller 3013 are provided on the upper layer of the main frame, and the propeller is used to adjust and control the horizontal position and rotation of the main frame.

[0041] Furthermore, optionally, as Figure 3 shown by the red frame, a large frame 21 (red) is suspended below the floating body by ropes to frame and separate all the ropes and cables belonging to two adjacent main frames in the horizontal direction, aiming to prevent these two groups of ropes and cables from entangling each other. The height of the large frame can be adjusted through a rope 22 connecting the large frame so that the large frame is always above the main frame with a relatively higher position among two adjacent main frames.

[0042] In asFigure 2 As shown, the main frame 3 is connected to the auxiliary frame 17. The auxiliary frame 17 is sleeved on the main rope 4. The main frame 3 and the auxiliary frame 17 are lifted and lowered along the main rope 4, and the main rope is used to guide the movement of the main frame and the auxiliary frame.

[0043] The main frame 3 and the auxiliary frame 17 are connected by a connecting cable or a rigid connecting link 18, and the length of the connecting cable can be adjusted.

[0044] When more than one main frame moves up and down by sleeving / framing on the same main rope through the auxiliary frame, they sometimes need to pass each other. Sensors 3013 are installed near the auxiliary frame that frames the main rope or on the main frame to sense their own depth and the distance from the other main frame. The sensors include pressure gauges, lights, cameras 19, sonars, etc. As Figure 5 shown, there are two upper and lower auxiliary frames for the main frame to sleeve the main rope or cable. When two main frames approach and need to pass each other, the upper auxiliary frame is released first, crosses the auxiliary frame of the other party, and then reframes the main rope. Then the lower auxiliary frame is untied, crosses the auxiliary frame of the other party, and then reframes the main rope to complete the passing process.

[0045] Furthermore, a plurality of auxiliary frames 17 are sleeved on the main rope 4. The auxiliary frame adopts a frame that can be opened and closed. As Figure 6 shown, various sensors are arranged on the auxiliary frame. The auxiliary frame is driven by a motor to open and close, and locks and unlocks the auxiliary frame with the main rope. Specifically, the auxiliary frame is connected to the rod member 20 through a rope. The rod member moves along the connecting rod between the main frame and the auxiliary frame under the drive of the motor, and then pulls the rope to open the auxiliary frame. The opened frame is closed under the action of the spring to realize the locking and unlocking of the auxiliary frame and the main rope.

[0046] In this embodiment, storage hooks are arranged at the bottom of the large floating body 1, and heavy objects are suspended on the storage hooks for gravitational energy storage. The storage hooks are connected to ropes. The height of the rope 9 suspending the heavy object is adjusted through the winch 10 on the floating body. The motor drives the winch to lift the rope to adjust the height of the heavy object. The plurality of suspended heavy objects are connected by a connecting member 11 of a rope or a rigid rod member.

[0047] In this embodiment, the storage hook and the winch are connected by a track. A pulley 12 is arranged on the track. The heavy object is transferred between the storage hooks through the pulley, and an underwater robot is configured to realize the suspension of the heavy object. Here, the existing technology is directly adopted to achieve this, and it will not be elaborated here.

[0048] In this embodiment, the anchor 14 can be a heavy object or an anchor. The anchor does not need to provide very high strength because its function is not to stabilize the position of the floating body. The anchor can even be one or more heavy objects placed on the seabed connected together. The seabed beacon can be placed above or near the anchor and used as an anchor 16 with a sonar beacon, and the length of the main rope can be adjusted.

[0049] The working principle of the offshore floating gravity energy storage system based on gravity energy storage provided in this embodiment is as follows:

[0050] To prevent the ropes belonging to different floating bodies from entangling with each other, one or more main ropes are connected between the floating body and the seabed anchor. Each main frame structure is sleeved / framed on one or more main ropes through one or several sub-frames and moves up and down along the main ropes. The multiple heavy objects and their ropes under each winch are restricted in their horizontal positions by a main frame, so that the ropes and cables belonging to the same main frame cannot entangle with each other. The various ropes and cables belonging to two adjacent main frames are also framed and separated by a large frame located above the two main frames, so that the ropes belonging to two adjacent main frames cannot entangle with each other. The above measures can prevent the various ropes from entangling with each other.

[0051] To prepare for charging, when the main frame and its affiliated ropes and hooks descend to near the seabed, the main frame hovers at a certain height. The propellers on the main frame adjust the horizontal position and rotation angle of the main frame. The multiple hooks under the main frame further descend in height. The heavy object hooks in the prior art have propellers and sensors and can move freely like an underwater robot and search for and hook the heavy objects on the seabed according to a digital map. Then, the winches and ropes lift each heavy object to the height where the main frame hovers, and then all the winches in a group lift all the heavy objects and the main frame up to the height of the floating body to store energy. At the bottom of the floating body, the heavy objects under the winches are transferred to the heavy object storage hooks at the bottom of the floating body for hanging storage.

[0052] When generating electricity, the winches hanging the heavy objects lower the heavy objects and the main frame to a height near the seabed. The main frame hovers at a certain height and does not continue to descend. The propellers on the main frame adjust the horizontal position and rotation angle of the main frame, and each heavy object under each winch further descends and places the heavy object on the seabed.

[0053] There are rigid and / or flexible connection devices and anti-collision pads between the heavy objects suspended under the floating body to prevent collision during strong winds and waves.

[0054] When the floating body needs to move away from its working position, for example, when it needs to return to the shipyard for maintenance, the floating body can be temporarily unlocked / disconnected from the main rope and the main auxiliary cable. The main rope and the main auxiliary cable can be moored by airbags floating on the water surface. When the floating body returns, it can be reconnected to the main rope and the main auxiliary cable.

[0055] Embodiment 2

[0056] In a typical embodiment of the present invention, a working method of an offshore floating gravity energy storage system based on gravity energy storage is provided, including:

[0057] When energy storage is required, after lifting the heavy object through the lifting device, the heavy object is suspended at the bottom of the floating body platform for gravity energy storage;

[0058] When power discharge is required, the heavy object at the bottom of the floating body platform is gradually sunk to the seabed, and the power generation device uses the gravity and potential energy of the heavy object to generate electricity;

[0059] During the ascending or descending process of the heavy object, the main frame encloses the heavy object and its affiliated ropes and ascends or descends synchronously with the heavy object, and the heavy object and the ropes suspending the heavy object are limited in the horizontal direction by the main frame to avoid entanglement between the ropes.

[0060] Although the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, it is not a limitation on the protection scope of the present invention. Those skilled in the art should understand that, based on the technical solutions of the present invention, various modifications or deformations that can be made by those skilled in the art without creative efforts are still within the protection scope of the present invention.

Claims

1. An offshore floating gravity energy storage system based on gravity energy storage, characterized in that, It includes a large floating body, on which a lifting device and a power generation device are provided. The lifting device is respectively connected to a heavy object and a main frame through ropes. During the process of the heavy object descending to the seabed, power is generated through the power generation device, and the heavy object is lifted to the large floating body for gravitational energy storage; the main frame can limit the horizontal position of multiple heavy objects, and the heavy object and the main frame can be lifted respectively through the ropes connected to them.

2. The floating offshore gravity energy storage system based on gravity energy storage according to claim 1, wherein The lifting device adopts a winch or a capstan or a crane. Multiple winches are provided, each winch is connected to a heavy object through a rope, one or more groups of winches are provided on each floating body, each group of winches includes multiple winches, and multiple heavy objects are connected under each group of winches through ropes; Each group of winches also corresponds to a main frame, and each main frame also has a winch and a rope to control its lifting; multiple heavy objects under each group of winches are horizontally limited by a main frame.

3. The offshore floating gravity energy storage system based on gravity energy storage according to claim 2, characterized in that, The main frame includes upper and lower planar layers. Among them, multiple rope limiting spaces are provided on the upper planar layer of the main frame to limit the horizontal position of the ropes or cables above the heavy objects, and the lower planar layer of the main frame is used to enclose a group of heavy objects; Further, sensors and propellers are provided on the upper layer of the main frame; The propeller is used to adjust and control the horizontal position and rotation of the main frame.

4. The offshore floating gravity energy storage system based on gravity energy storage according to claim 3, characterized in that: The large floating body is connected to an anchor on the seabed through a main rope, the length of the main rope can be adjusted, and the large floating body floats in a specific area on the sea surface.

5. The offshore floating gravity energy storage system based on gravity energy storage according to claim 4, characterized in that Storage hooks are provided at the bottom of the large floating body, and the heavy objects are hung on the storage hooks for gravitational energy storage. Multiple suspended heavy objects are connected through ropes or rigid rods.

6. The floating offshore gravity energy storage system based on gravity energy storage according to claim 4, wherein The main frame is connected to a sub-frame, the sub-frame is sleeved on the main rope, and the main frame and the sub-frame are lifted along the main rope; The sub-frame is connected to the upper layer of the main frame; Or, the lower layer of the main frame is connected; Or, the upper and lower layers of the main frame are respectively connected to the sub-frame; The main frame and the sub-frame are connected through rigid connecting rods and / or ropes. When connected by ropes, the length of the ropes can be adjusted.

7. The floating offshore gravity energy storage system based on gravity energy storage according to claim 6, characterized in that, Multiple sub-frames are sleeved on the main rope. The sub-frame adopts a frame that can be opened and closed. A variety of sensors are provided on the sub-frame. The sub-frame is driven by a motor to open and close, and the sub-frame is locked and unlocked with the main rope.

8. The offshore floating gravity energy storage system based on gravity energy storage according to claim 7, characterized in that, During the ascending or descending process of the main frame, the sub-frame moves along the main rope, and the movement of the main frame and the sub-frame is guided by the main rope. When two sub-frames on the main rope approach and need to pass by each other, one of the sub-frames crosses over the other frame and then re-frames the main rope.

9. The offshore floating gravity energy storage system based on gravity energy storage according to claim 1, characterized in that A large frame is hung under the large floating body by a winch and a rope to enclose and separate all the ropes and cables belonging to two adjacent main frames in the horizontal direction to prevent these two groups of ropes and cables from winding around each other. The large frame is located above two adjacent main frames in the horizontal direction in the vertical direction, and the depth of the large frame can be adjusted by the length of its hanging rope.

10. A working method of an offshore floating gravity energy storage system based on gravity energy storage according to any one of claims 1-9, characterized in that, It includes: When energy storage is required, after lifting the heavy object through the lifting device, the heavy object is hung at the bottom of the floating body platform for gravitational energy storage; When power generation is required, the heavy objects at the bottom of the floating body platform are gradually sunk to the seabed, and the power generation device uses the gravity and potential energy of the heavy objects to generate electricity; During the rising or falling process of the heavy objects, the main frame encloses the heavy objects and their affiliated ropes and rises or falls synchronously with the heavy objects. The main frame limits the heavy objects and the ropes hanging the heavy objects in the horizontal direction to avoid entanglement between the ropes.

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