A fully enclosed double-floating wave energy power generation device

Abstract

The present invention discloses a fully enclosed double-floating wave energy power generation device, comprising an outer float, an inner float, a buffer device, a cable winding device and a nonlinear bistable device; the buffer device is connected to a hydraulic device and a hydraulic power generation device; a wave-shaped groove is provided on the side of the inner float; the outer float comprises a buoy, a partition arranged in the buoy, and an energy-capturing buoy sleeved on the buoy; the cable winding device is located on the partition; an opening is provided on the partition, and a guide wheel with a rotating shaft is provided in the opening; the nonlinear bistable device comprises a pressure rod, a spring, and a sleeve fixed on the inner side of the buoy; the cable winding device comprises a cable winding rope, a cable power generation device, a transmission shaft, a spring plate bracket and a spring plate; the present invention utilizes the nonlinear bistable device to provide a nonlinear restoring force to cause two stable equilibrium positions to appear when the outer float and the inner float undergo relative vertical motion, thereby forming a bistable system, amplifying the motion amplitude of the float under wave excitation, expanding the capture frequency bandwidth, and improving the wave energy capture efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of wave power generation, and in particular to a fully enclosed double-floating wave energy power generation device. Background Art

[0002] With the rapid development of the economy, energy demand is increasing, but this has also led to energy shortages and environmental pollution. The development of renewable energy is urgent. Wave energy, as an important marine renewable energy source, can generate 8,000-80,000 TWh of electricity annually, offering enormous development prospects. Wave energy generation technology involves capturing wave energy and converting it into usable electrical energy through an energy output system. Systems that capture wave energy are called wave energy conversion systems or wave energy generation systems. Wave energy devices have diverse structural forms and can be categorized based on their principles into oscillating water column, overriding, and oscillating float types. The oscillating float double-floating wave energy device has attracted widespread attention due to its simple structure and high stability.

[0003] While oscillating buoy-type double-floating wave energy converters (WECs) have promising application potential in wave energy capture, most such devices are linear. These devices face two major challenges during their development: low capture efficiency and a narrow bandwidth. The conversion efficiency of a WEC depends on many factors, including the incident wave frequency, device shape, draft, center of gravity, and parameters of the energy conversion system. To achieve optimal wave energy capture efficiency, linear WECs typically resonate at a specific frequency. However, since the dominant frequency of waves can vary over time, deviating from the system's design frequency, this can lead to poor efficiency. Furthermore, real waves are irregular waves with spectral characteristics. The narrow capture bandwidth of WECs prevents them from effectively capturing energy from the various frequencies of irregular waves, thus impacting overall capture efficiency.

[0004] In addition, many components of the traditional oscillating float double-floating body wave energy power generation device are exposed to seawater. The harsh working environment (high salinity, strong winds, huge waves) will greatly reduce the working reliability of many components and affect the stability of the wave energy conversion device. Summary of the Invention

[0005] Purpose of the invention: In response to the above-mentioned deficiencies in the prior art, the present invention proposes a fully enclosed double-floating wave energy power generation device. By placing the inner float and other devices inside the outer float, a fully enclosed double-floating wave energy power generation device is constructed to avoid contact between the devices and seawater. At the same time, a nonlinear bistable device is introduced to make the wave energy power generation device have relatively high adaptability to sea areas, and at the same time provide a nonlinear restoring force to allow two stable equilibrium positions to appear when relative heaving motion occurs between the outer float and the inner float, forming a bistable system. Under wave excitation, the inter-well jumping mechanism of the bistable system is used to amplify the motion amplitude of the float and expand the capture bandwidth, thereby effectively improving the wave energy capture efficiency.

[0006] Technical solution: The fully enclosed double-floating wave energy power generation device of the present invention includes an outer float, an inner float, a buffer device, a cable winding device, and a nonlinear bistable device; the buffer device is connected to a hydraulic device and a hydraulic power generation device; the side of the inner float is provided with a wave-shaped groove; the bottom of the inner float is connected to the bottom of the outer float through the buffer device;

[0007] The outer float includes a buoy, a partition arranged inside the buoy, and an energy-capturing float sleeved on the buoy; the rope reel is located on the partition; an opening is provided on the partition, and a guide wheel with a rotating shaft is provided in the opening;

[0008] The nonlinear bistable device includes a pressure rod, a spring, and a sleeve fixed on the inner side of the float; one end of the pressure rod is connected to a roller; the other end of the pressure rod passes through the sleeve and is connected to the sleeve through the spring; the roller is embedded in the wave-shaped groove;

[0009] The cable winding device includes a cable winding rope, a cable winding power generation device, a transmission shaft, a spring leaf bracket and a spring leaf; the cable winding power generation device and the spring leaf bracket are arranged at both ends of the transmission shaft, and the spring leaf is arranged in the spring leaf bracket and connected to the transmission shaft; one end of the cable winding rope is connected to the top of the inner floating body through a guide wheel, and the other end of the cable winding rope is wound around the transmission shaft.

[0010] The buffer device includes a spring buffer, a buffer plate, and cross-connected hinged telescopic rods; one end of the cross-connected hinged telescopic rod is connected to the bottom of the buffer plate through the spring buffer, and the other end is connected to the hydraulic device.

[0011] The hydraulic device is located at the bottom of the buoy and is connected to the buffer device to convert the mechanical energy of the waves into hydraulic energy.

[0012] The spring buffer comprises a buffer spring, a buffer rod and a buffer cylinder; the buffer rod passes through the top of the buffer cylinder, and the buffer spring is located between the buffer rod and the buffer cylinder.

[0013] One end of the pressure rod is provided with a hinged fastener, and the pressure rod is connected to the roller through the hinged fastener.

[0014] A hinged fastener is provided on the top of the inner floating body, and one end of the winding rope is connected with the hinged fastener on the top of the inner floating body through a guide wheel in an opening of the partition plate.

[0015] The nonlinear bistable devices are distributed in multiple layers inside the buoy.

[0016] The bottom of the buoy is provided with a plurality of hinged fixtures, which are connected to the buffer plate through cross-connected hinged telescopic rods.

[0017] The inner float is located on the buffer plate of the buffer device, and the buffer device buffers the movement of the inner float to avoid collision between the inner float and the outer float and cause damage.

[0018] The energy-capturing float is an annular hollow float, which provides buoyancy and anti-overturning capability.

[0019] Working Principle: This invention constructs a fully enclosed dual-float wave energy device by placing the inner buoy and all other devices inside the outer buoy. This prevents contact between the devices and seawater, improving the device's long-term operational reliability. Furthermore, a nonlinear bistable device is introduced. Its nonlinear characteristics provide a nonlinear restoring force, enabling two stable equilibrium positions to emerge during relative heave motion between the outer and inner buoys, forming a bistable system. Under wave excitation, the inter-well hopping mechanism of the bistable system amplifies the motion amplitude of the floats, widening the capture bandwidth and effectively improving wave energy capture efficiency.

[0020] Beneficial effects: Compared with the prior art, the present invention has the following advantages:

[0021] (1) The fully enclosed double-floating wave energy power generation device of the present invention improves the working reliability of the wave energy power generation device by placing the inner floating body and other devices inside the outer floating body, thereby making it more adaptable to sea areas.

[0022] (2) On the other hand, the present invention introduces a nonlinear bistable device, which is introduced between the outer float and the inner float. Based on the mutual cooperation of multiple functional components, a nonlinear restoring force is generated through the relative heaving motion between the outer float and the inner float, so that two stable equilibrium positions appear when the relative heaving motion occurs between the outer float and the inner float, which is conducive to the generation of large-amplitude inter-well oscillations between the outer float and the inner float between different stable equilibrium positions, so as to expand the frequency bandwidth of the wave energy power generation device, improve the wave energy capture efficiency, and ensure stable and reliable energy output.

[0023] (3) The fully enclosed double-floating wave energy power generation device of the present invention is anchored to the seabed through an external anchor chain, thereby achieving the collection and power generation of wave energy while ensuring a certain degree of marine survivability. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic diagram of the overall structure of the fully enclosed double-floating wave energy power generation device of the present invention;

[0025] Figure 2 This is a schematic diagram of the internal structure of the fully enclosed double-floating wave energy power generation device of the present invention;

[0026] Figure 3 It is a schematic structural diagram of the outer floating body of the present invention;

[0027] Figure 4 It is a schematic structural diagram of the inner floating body of the present invention;

[0028] Figure 5 It is a structural schematic diagram of the hydraulic device of the present invention;

[0029] Figure 6 It is a schematic structural diagram of the buffer device of the present invention;

[0030] Figure 7 It is a structural schematic diagram of the spring buffer of the present invention;

[0031] Figure 8 It is a structural schematic diagram of the cable winding device of the present invention;

[0032] Figure 9 It is a schematic structural diagram of the nonlinear bistable device of the present invention;

[0033] Figure 10 It is a schematic diagram of the cooperation between the inner float and the nonlinear bistable device of the present invention;

[0034] Figure 11 2 is a schematic diagram of a potential energy function curve of a nonlinear bistable device of the present invention;

[0035] Figure 12 This is a comparison of the wave energy capture width of the nonlinear bistable device of the present invention and the traditional linear device;

[0036] Figure 13 This is a schematic diagram of the structure of the energy-capturing float of the present invention;

[0037] Figure 14 It is a schematic diagram of the partition and guide wheel of the present invention. DETAILED DESCRIPTION

[0038] like Figures 1 to 14 As shown, the fully enclosed double-floating body wave energy power generation device of the present invention includes an outer floating body 1, an inner floating body 2, a hydraulic device 3, a hydraulic power generation device 7, a buffer device 4, a cable winding device 5, and a nonlinear bistable device 6. The inner floating body 2, the hydraulic device 3, the hydraulic power generation device 7, the buffer device 4, the cable winding device 5, and the nonlinear bistable device 6 are all arranged inside the outer floating body 1.

[0039] The outer buoy 1 includes a buoy 1-2, a top cover 1-1 installed on the top of the buoy 1-2, a partition 1-3 arranged inside the buoy 1-2 and above the inner buoy, and an energy-capturing buoy 1-4 sleeved on the outside of the buoy 1-2.

[0040] The inner float 2 is located on the buffer plate of the buffer device 4, the cable winding device 5 is placed on the partition 1-3, the inner float 2 is connected to the cable winding device 5 through the top hinged fastener, and the nonlinear bistable device 6 is arranged on the inner side of the buoy.

[0041] like Figure 13 As shown, the energy-harvesting float 1-4 is an annular hollow float. In this embodiment, the energy-harvesting float 1-4 is welded to the outer wall of the buoy 1-2, thereby providing buoyancy and anti-overturning capability. The inner bottom of the buoy 1-2 is provided with multiple hinged fasteners 8 for connecting the hinged telescopic rod 4-1.

[0042] like Figure 14 As shown, in this embodiment, the partition 1-3 is provided with three holes, and a rotating shaft and a guide wheel 1-5 are provided in the holes. The rotating shaft passes through the center hole of the guide wheel 1-5, and the guide wheel 1-5 rotates freely around the rotating shaft. The guide wheel 1-5 is used to guide the winding rope 5-1.

[0043] The hydraulic device 3 comprises a hydraulic rod 3-1, a hydraulic cylinder 3-2, and an articulated telescopic rod 4-1. The hydraulic device 3 and the buffer device 4 are located at the bottom of the buoy 1-2. A hydraulic generator 7 is located in the center of the bottom of the buoy 1-2. The inner buoy 2 is positioned above the buffer device 4. A cable reel 5 is positioned on the bulkhead 1-3. The inner buoy 2 is connected to the cable reel 5 via a hinged fixture 8 at the top. A nonlinear bistable device 6 is located on the inner sidewall of the buoy 1-2. The roller 6-4 of the nonlinear bistable device 6 is embedded in a wave-shaped groove 2-1 on the side of the inner buoy 2.

[0044] like Figure 5-6 As shown, the inner bottom of the pontoon 1-2 is provided with three groups of articulated fasteners 8 and three groups of hydraulic devices 3, each group of articulated fasteners 8 and hydraulic devices 3 is connected to an articulated telescopic rod 4-1, and the two articulated telescopic rods 4-1 are cross-interconnected. The two articulated telescopic rods 4-1 are respectively connected to an articulated telescopic rod 4-1, and the added articulated telescopic rods 4-1 are still cross-interconnected, and one of the added articulated telescopic rods 4-1 is hinged to the articulated fastener 8 at the bottom of the buffer plate 4-3, and the other is connected to the spring buffer 4-2, and the spring buffer 4-2 is then articulated to the articulated fastener 8 at the bottom of the buffer plate 4-3.

[0045] The buffer device 4 includes a hinged telescopic rod 4-1, a spring buffer 4-2 and a buffer plate 4-3. Figure 7As shown, the spring buffer 4-2 is composed of a buffer spring 4-2-1, a buffer rod 4-2-2, a buffer cylinder 4-2-3 and hinged fasteners 8 at both ends. The buffer rod 4-2-2 passes through the top of the buffer cylinder 4-2-3 and is coaxial with the buffer spring 4-2-1. The buffer rod 4-2-2 is located between the buffer rod 4-2-2 and the buffer cylinder 4-2-3. When the inner float 2 generates a vertical swing motion in the outer float 1, the buffer device 4 acts as a buffer for the movement of the inner float 2, preventing the inner float 2 and the outer float 1 from colliding and causing damage, thereby affecting the stability of the wave energy conversion device. Secondly, the buffer spring 4-2 in the buffer device 4 also acts as an energy storage device while the inner float 2 compresses the buffer device 4, providing auxiliary power to the inner float 2, which is conducive to generating a larger motion amplitude when the inner float 2 and the outer float 1 move relative to each other. In addition, the hydraulic power generation device 7 arranged at the center of the bottom of the float 1-2 is connected to the hydraulic device 3 through a pipeline. The hydraulic device 3 is used to convert the mechanical energy of the waves into hydraulic energy; the hydraulic power generation device 7 is used to convert the hydraulic energy into electrical energy.

[0046] like Figure 4 As shown, the inner float 2 is placed on the buffer plate 4-3 of the buffer device, the top of the inner float 2 is provided with a hinged fastener 8 for connecting the rope winding device 5, and the side of the inner float 2 is provided with three wave-shaped grooves 2-1.

[0047] like Figure 9-10 As shown, the nonlinear bistable device 6 includes a pressure rod 6-1, a spring 6-2, and a sleeve 6-3. One end of the pressure rod 6-1 is provided with a hinged fastener 8 and connected to a roller 6-4, which is freely rotatable. The pressure rod 6-1 passes through the top of the sleeve 6-3 and is coaxial with the spring 6-2. The spring 6-2 is located between the bottom surfaces of the pressure rod 6-1 and the bottom surfaces of the sleeve 6-3.

[0048] The nonlinear bistable device 6 is provided in two layers, with three equidistant arrays in each layer around the buoy 1-2. The bottom of the sleeve 6-3 of each nonlinear bistable device 6 is welded to the inner wall of the buoy 1-2, and the roller 6-4 is embedded in the wave-shaped groove 2-1 on the side of the inner float 2 and abuts against the inner float 2. When the inner float 2 moves to the point where the roller 6-4 of the nonlinear bistable device 6 abuts the vertex of the wave-shaped groove 2-1, as shown in FIG. Figure 10 As shown, the spring 6-2 in the nonlinear bistable device 6 is in the maximum compression state, and the system potential energy is large (the calculation formula of the system potential energy here is E=k*x 2 , where k is the spring stiffness of spring 6-2 and x is the spring extension), the system is in an unstable state. At this time, no matter whether the inner floating body 2 has an upward or downward movement trend, the nonlinear bistable device 6 will provide a corresponding upward or downward thrust, causing the inner floating body 2 to produce a larger heaving motion amplitude, such as Figure 11As shown, at this time, a potential barrier will appear in the system potential energy function of the wave energy power generation device, that is, the expansion and contraction amount x of the spring 6-2 reaches the maximum value, so that the potential energy function E reaches the maximum value; when the inner floating body 2 moves upward or downward to the lowest point where the roller 6-4 of the nonlinear bistable device 6 presses against the wave-shaped groove 2-1, as shown in FIG. Figure 10 As shown, the system is in a stable state. Two potential wells will appear in the system potential energy function of the wave power generation device. At this time, the expansion and contraction amount x of the spring 6-2 reaches the minimum. According to the calculation formula of the potential energy function E=k*x 2 , at this time, the potential energy also reaches its minimum value, that is, two potential wells appear. When the system moves from an unstable state to a stable state, the expansion and contraction amount x of spring 6-2 decreases, and spring 6-2 releases energy. At this time, spring 6-2 exerts a thrust in the same direction as the movement direction of inner float 2 on inner float 2 through the roller, that is, nonlinear restoring force, which is conducive to generating a larger motion amplitude when inner float 2 and outer float 1 move relative to each other, such as Figure 12 As shown in the figure, due to the addition of nonlinear devices, the energy capture width is widened to the low-frequency region, and its peak value is much higher than that of traditional linear devices, which plays a role in expanding the capture bandwidth and improving the wave energy capture efficiency.

[0049] like Figure 8 As shown, the cable winding device 5 is installed on the partition 1-3 and consists of a cable winding rope 5-1, a cable winding generator 5-2, a transmission shaft 5-3, a spring bracket 5-4, and a spring plate 5-5. The cable winding generator 5-2 and the spring bracket 5-4 are installed at both ends of the transmission shaft 5-3. The spring plate 5-5 is located in the spring bracket 5-4 and is fixedly connected to the transmission shaft 5-3. The cable winding rope 5-1 passes through a hole in the partition 1-3. One end is connected to the hinged fixture 8 at the top of the inner float 2 through the cable joint 5-1-1. The other end is fixed and wrapped around the transmission shaft 5-3. When the cable winding rope 5-1 is pulled, the transmission shaft 5-3 rotates along with the cable winding rope 5-1. When the inner buoy 2 moves downward relative to the outer buoy 1, the windup rope 5-1 is pulled, driving the transmission shaft 5-3 to rotate, tightening the spring 5-5 and storing energy. When the inner buoy 2 moves downward to its maximum distance relative to the outer buoy 1, that is, the inner buoy 2 remains stationary due to inertia while the outer buoy 1 moves upward due to the waves, the inner buoy 2 compresses the buffer device 4 and pulls the windup rope 5-1 until the inner buoy 2 no longer remains stationary and moves upward with the outer buoy 1. At this time, the spring 5-5 begins to release energy, driving the transmission shaft 5-3 to rotate in the opposite direction to retract the windup rope 5-1. During the rotation of the transmission shaft 5-3, the windup rope generator 5-2 converts mechanical energy into electrical energy.

[0050] The working method of the fully enclosed double-floating wave energy power generation device of the present invention is as follows:

[0051] (1) The outer buoy 1 is anchored to the seabed through the anchor chain 9, and the energy-capturing buoy 1-4 floats on the water surface. Under the action of waves, the energy-capturing buoy 1-4 absorbs wave energy and drives the buoy 1-2 to produce a vertical motion. The buffer device 4 and the reel device 5 transfer the wave energy captured by the energy-capturing buoy 1-4 and the buoy 1-2 to the inner buoy 2. Specifically, when the outer buoy 1 moves upward relative to the inner buoy 2, the buffer device 4 is compressed, generating an upward thrust on the inner buoy 2, and the reel rope 5-1 in the reel device 5 is pulled, generating an upward pulling force on the inner buoy 2, thereby The wave energy is transferred to the inner floating body 2; the inner floating body 2 also undergoes heaving motion under the thrust of the buffer device 4 and the tension of the cable winding device 5; and when the outer floating body 1 just starts to move, the inner floating body 2 remains in its original stationary state due to inertia, and only undergoes heaving motion under the action of the buffer device 4 and the cable winding device 5. At the same time, due to the different overall structures and mass parameters of the outer floating body 1 and the inner floating body 2, the two have different resonant frequencies, and thus produce relative displacement, thereby driving the hydraulic device 3 to generate hydraulic motion and the transmission shaft 5-3 of the cable winding device 5 to generate rotational motion.

[0052] (2) Under the action of the inner floating body 2, part of the captured energy is converted into hydraulic energy through the hydraulic device 3, and further drives the engine in the hydraulic power generation device 7 through the pipeline to generate electricity; the other part is converted into elastic potential energy through the winding device 5, and further drives the generator in the winding power generation device 5-2 through the transmission shaft 5-3 to convert the wave energy into electrical energy.

[0053] (3) During the movement of the outer floating body 1 and the inner floating body 2, the nonlinear bistable device 6 provides a nonlinear restoring force, which makes the outer floating body 1 and the inner floating body 2 produce a larger motion amplitude when moving relative to each other, thereby expanding the captured frequency bandwidth and improving the capture efficiency of wave energy.

Claims

1. A fully enclosed double-floating wave energy power generation device, characterized by: The invention comprises an outer floating body (1), an inner floating body (2), a buffer device (4), a cable winding device (5), and a nonlinear bistable device (6); the buffer device (4) is connected to a hydraulic device (3) and a hydraulic power generation device (7); a wavy groove (2-1) is provided on the side surface of the inner floating body (2); and the bottom of the inner floating body (2) is connected to the bottom of the outer floating body (1) through the buffer device (4); The outer floating body (1) comprises a buoy (1-2), a partition (1-3) arranged inside the buoy (1-2), and an energy-capturing buoy (1-4) sleeved on the buoy (1-2); the rope reel device (5) is located on the partition (1-3); an opening is provided on the partition (1-3), and a guide wheel (1-5) with a rotating shaft is provided in the opening; The nonlinear bistable device (6) comprises a pressure rod (6-1), a spring (6-2), and a sleeve (6-3) fixed on the inner side of a buoy (1-2); one end of the pressure rod (6-1) is connected to a roller (6-4); the other end of the pressure rod (6-1) passes through the sleeve (6-3) and is connected to the sleeve (6-3) via a spring (6-2); the roller (6-4) is embedded in the wave-shaped groove (2-1); The cable winding device (5) comprises a cable winding rope (5-1), a cable winding power generation device (5-2), a transmission shaft (5-3), a spring plate bracket (5-4) and a spring plate (5-5); the cable winding power generation device (5-2) and the spring plate bracket (5-4) are arranged at both ends of the transmission shaft (5-3), and the spring plate (5-5) is arranged in the spring plate bracket (5-4) and connected to the transmission shaft (5-3); one end of the cable winding rope (5-1) is connected to the top of the inner floating body (2) through the guide wheel (1-5), and the other end of the cable winding rope is wound around the transmission shaft (5-3).

2. The fully enclosed double-floating wave energy power generation device according to claim 1, characterized in that: The buffer device comprises a spring buffer (4-2), a buffer plate (4-3), and cross-connected hinged telescopic rods (4-1); one end of the cross-connected hinged telescopic rod (4-1) is connected to the bottom of the buffer plate (4-3) through the spring buffer (4-2), and the other end is connected to the hydraulic device (3).

3. The fully enclosed double-floating wave energy power generation device according to claim 1, characterized in that: The hydraulic device (3) is located at the bottom of the buoy (1-2).

4. The fully enclosed double-floating wave energy power generation device according to claim 2, characterized in that: The spring buffer (4-2) comprises a buffer spring (4-2-1), a buffer rod (4-2-2) and a buffer cylinder (4-2-3); the buffer rod (4-2-2) passes through the top of the buffer cylinder (4-2-3), and the buffer spring (4-2-1) is located between the buffer rod (4-2-2) and the buffer cylinder (4-2-3).

5. The fully enclosed double-floating wave energy power generation device according to claim 1, characterized in that: One end of the pressure rod (6-1) is provided with a hinged fastener (8), and the pressure rod (6-1) is connected to the roller (6-4) via the hinged fastener (8).

6. The fully enclosed double-floating wave energy power generation device according to claim 1, characterized in that: A hinged fastener (8) is provided on the top of the inner floating body (2), and one end of the winding rope (5-1) is connected to the hinged fastener (8) on the top of the inner floating body (2) through a guide wheel (1-5) in an opening of the partition (1-3).

7. The fully enclosed double-floating wave energy power generation device according to claim 1, characterized in that: The nonlinear bistable device (6) is distributed in multiple layers inside the buoy (1-2).

8. The fully enclosed double-floating wave energy power generation device according to claim 2, characterized in that: The bottom of the buoy (1-2) is provided with a plurality of hinged fasteners (8), and the hinged fasteners are connected to the buffer plate (4-3) via cross-connected hinged telescopic rods (4-1).

9. The fully enclosed double-floating wave energy power generation device according to claim 2, characterized in that: The inner float (2) is located on the buffer plate (4-3) of the buffer device.

10. The fully enclosed double-floating wave energy power generation device according to claim 1, characterized in that: The energy-capturing float (1-4) is an annular hollow float.

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