Integrated floater drive and oscillating water column collaborative wave power generation device

Abstract

The application discloses an integrated float driving and oscillating water column collaborative wave absorbing and power generation device, which comprises an oscillating water column box, an oscillating water column type power generation device, a float type power generation device and an energy storage device, and the oscillating water column box adopts a variable-diameter structure with a wide upper chamber and a narrow lower chamber. Compared with the prior art, the application reduces the system inherent frequency by reducing the cross-sectional area of the lower chamber, so that the oscillating water column type power generation device can efficiently resonate with low-frequency waves under the condition of a small draught; the wave energy is converted into stable rotary mechanical energy for power generation through the up-and-down movement of the float in the vertical direction; the oscillating water column type power generation device is driven by the alternating airflow generated by the oscillation of the water column, the electric energy generated by the two sets of power generation devices is stored in a super capacitor after rectification, and the collaborative capture of wide-frequency wave energy is realized. Meanwhile, the application has excellent wave absorbing and protecting functions, and has a compact structure and is suitable for array arrangement.

Description

Technical Field

[0001] This invention relates to the field of marine renewable energy technology, specifically to an integrated float-driven and oscillating water column coordinated wave-damping and power generation device. Background Technology

[0002] With the deepening of global energy structure transformation, the development and utilization of clean and renewable ocean energy, especially wave energy, has increasingly become a research hotspot. Wave energy has advantages such as high energy density, wide distribution, and strong predictability. Among them, the oscillating water column (OWC) device has become one of the most promising technical routes due to its relatively simple structure, high reliability, and strong adaptability.

[0003] Currently, conventional open-wave energy capture (OWC) devices typically employ a chamber structure with a uniform cross-section. Their energy capture efficiency is highly dependent on the degree of matching between the natural frequency of the water column oscillation within the chamber and the incident wave frequency. Studies have shown that in energy-rich low-frequency long-wave sea areas, traditional OWC devices often require extremely deep chamber drafts to achieve resonant capture. This results in large structural dimensions, high construction and installation costs, limiting their economic viability and applicability. Furthermore, single OWC devices have limited adaptability to wave frequencies when facing complex sea conditions, leaving significant room for improvement in overall energy efficiency. Additionally, their chamber openings directly bear the wave impact, posing structural safety risks in harsh sea conditions. On the other hand, point-absorption type (such as float-type) wave energy devices are sensitive to short-to-medium period waves, and their energy capture systems (such as hydraulic or mechanical transmissions) can efficiently extract energy directly from the violent motion of the float. However, simple float-type devices have relatively low capture efficiency under long-wave conditions, and their energy conversion systems are typically complex. While existing technologies have attempted to combine different forms of wave energy capture devices, these are mostly simple physical superpositions, failing to achieve deep synergy and optimization of the two mechanisms in terms of structure and function. Therefore, a new power generation device is urgently needed to solve the aforementioned technical problems. Summary of the Invention

[0004] Purpose of the invention: The present invention aims to overcome the above-mentioned defects and provide an integrated float-driven and oscillating water column coordinated wave-damping and power generation device to solve the problems of large resonant draft, weak impact resistance and limited wave energy capture efficiency of traditional OWC devices under low-frequency waves.

[0005] Technical Solution: To achieve the above objectives, the integrated float-driven and oscillating water column coordinated wave-damping and power generation device of the present invention includes an oscillating water column box with an internal oscillating water column chamber, an air hole located at the center of the top of the oscillating water column box, an oscillating water column power generation device placed in the air hole, a float-type power generation device located in the oscillating water column box, and energy storage devices located in the oscillating water column box and on both sides of the oscillating water column chamber; the float-type power generation device includes an eccentric shaft with a transverse axis, a float connected to the eccentric shaft, a flywheel coaxially arranged with the eccentric shaft, and a first generator with a gear drive perpendicular to the flywheel; the oscillating water column chamber includes an upper chamber and a lower chamber, the horizontal cross-sectional area of ​​the upper chamber being larger than that of the lower chamber; the two side walls of the lower chamber are respectively provided with channels extending upward to the top of the box; the bottom of the channels communicates with the lower chamber; the bottom of the lower chamber penetrates the oscillating water column box; the float is located in the channel and suspended below the eccentric shaft; the oscillating water column power generation device includes a second generator and a rotating impeller coaxially arranged with the second generator.

[0006] Furthermore, the energy storage device is electrically connected to the oscillating water column power generation device and the float power generation device.

[0007] Furthermore, the horizontal cross-section of the upper chamber is a large rectangle with a side length of [missing information]. The lower chamber has a small square cross-section with a side length of [missing information]. .

[0008] Furthermore, the structure of the oscillating water column chamber is designed based on the Helmholtz resonance principle, and the lower chamber is a slender pipe structure.

[0009] Furthermore, there are two float-type power generation devices and channels, which are symmetrically arranged on the left and right sides perpendicular to the direction of incident wave propagation.

[0010] Furthermore, the flywheel is provided with a large gear on its outer edge, which meshes perpendicularly with the small gear.

[0011] Furthermore, the energy storage device is installed in the bottom cavity of the wave-facing side and the wave-repellent side of the oscillating water column tank.

[0012] Furthermore, the pores are circular.

[0013] Furthermore, the side length of the horizontal cross-section of the lower chamber... As the volume decreases, the natural frequency of the water inside the oscillating water column chamber drops.

[0014] Furthermore, the formula for the natural frequency is as follows:

[0015] ,in, It is gravitational acceleration. It is the effective height below the water surface in the upper chamber. It is the effective height of the lower chamber. , , Fixed and unchanging, The larger the value, the smaller the natural frequency.

[0016] Beneficial Effects: Compared with existing technologies, this invention has the following significant advantages: Based on the Helmholtz resonator principle, the OWC chamber is designed with a variable diameter structure that is wider at the top and narrower at the bottom, reducing the natural frequency of the water column. This makes it easier for the device to resonate with low-frequency long waves at the same draft; or, at the same resonant frequency, a smaller draft is required, reducing structural construction costs and material usage. Integrating the float-type power generation device and the OWC power generation device into one unit, the float-type power generation device is sensitive to medium and short waves, while the OWC power generation device is highly efficient at capturing long waves. Their collaborative operation achieves the division of labor in capturing and coordinating the conversion of wave energy at different frequencies, effectively broadening the device's operating frequency band and improving the overall power generation efficiency under complex sea conditions. The symmetrically arranged float-type power generation device, while capturing wave energy, also first consumes and reflects a portion of the wave energy, reducing the wave height and wave energy directly impacting the OWC chamber, lessening the structural load, and improving the overall device's survivability and service life under harsh sea conditions. In the float-type power generation system, the intermittent, variable-speed mechanical energy generated by the reciprocating motion of the float is converted into stable, high-speed unidirectional rotational mechanical energy through the transmission design of "eccentric shaft-flywheel-speed-increasing gear set," improving the power generation efficiency and quality of the first generator. Simultaneously, the supercapacitor, in conjunction with the current integrator, can smooth out power output fluctuations caused by wave irregularities in both power generation devices, achieving efficient energy storage and smooth output, thus improving power quality. The overall device has a compact structure and high functional integration, serving as a standard power generation unit. Multiple units can be flexibly arranged in single-row or multi-dimensional arrays according to sea conditions. By differentiating the dimensions or drafts of the lower chambers of different units within the array, the entire array can adapt to a wider wave spectrum, achieving both large-scale wave energy generation and coastal protection functions. Attached Figure Description

[0017] Figure 1 This is a cross-sectional view along the incident wave propagation direction of the integrated float-driven and oscillating water column wave-damping and power generation device of the present invention.

[0018] Figure 2 This is a cross-sectional view of the integrated float-driven and oscillating water column wave-damping and power generation device of the present invention, perpendicular to the direction of incident wave propagation.

[0019] Figure 3 This is a schematic diagram of a float-type power generation device.

[0020] Figure 4 This is a cross-sectional view of the first generator.

[0021] Figure 5 This is a schematic diagram of an oscillating water column power generation device.

[0022] Figure 6 This is a cross-sectional view of the float oscillation guide mechanism.

[0023] Figure 7 This is a schematic diagram of the electrical energy flow generated by the integrated float-driven and oscillating water column wave-damping power generation device.

[0024] Figure 8 This is a cross-sectional view of the oscillating water column chamber.

[0025] Figure 9 A schematic diagram of a compact array formed by multiple integrated float-driven and oscillating water column collaborative wave-damping and power generation devices.

[0026] Figure 10 A schematic diagram of an array of spaced-out devices formed by multiple integrated float-driven and oscillating water column wave-damping and power generation devices. Detailed Implementation

[0027] This invention discloses an integrated float-driven and oscillating water column coordinated wave-damping and power generation device. Please refer to [reference needed]. Figures 1 to 7 The following is a further detailed description of the integrated float-driven and oscillating water column coordinated wave-damping and power generation device provided by the present invention: The device includes an oscillating water column (OWC) housing 1, a float-type power generation device 2, an oscillating water column-type power generation device 3, and an energy storage device 4. The energy storage device 4 is electrically connected to the oscillating water column-type power generation device 3 and the float-type power generation device 2 for collecting and storing electrical energy. The OWC housing 1 is the main structure of the device. A circular air hole 31 is provided at the center of the top of the OWC housing 1, and the oscillating water column-type power generation device 3 is installed inside the air hole 31. The OWC housing 1 has an OWC chamber 30 inside, which includes an upper chamber 101 and a lower chamber 102. The upper chamber 101 has a large rectangular horizontal cross-section with a side length of [missing information]. The bottom of the lower chamber 102 penetrates the oscillating water column box 1. The horizontal cross-section of the lower chamber 102 is a small square with a side length of [missing information]. Based on the Helmholtz resonance principle, the lower chamber 102 adopts a slender pipe structure, thus forming a variable diameter structure with the upper chamber 101 that is "wider at the top and narrower at the bottom". This reduces the natural frequency of the water column, making it easier for the device to resonate with low-frequency long waves at the same draft; or requiring a smaller draft at the same resonant frequency, reducing construction costs and material usage. The lower chamber 102 has two channels 32 extending upwards to the top of the OWC housing 1 on each of its two side walls. These channels 32 are symmetrically arranged on the left and right sides perpendicular to the direction of incident wave propagation, and their bottoms are connected to the lower chamber 102.

[0028] Two float-type power generation devices 2 are provided, with one float-type power generation device 2 in each channel 32. In this embodiment, the channel 32 is L-shaped, that is, it includes a longitudinally extending channel portion and a transversely extending channel portion at the bottom. The float-type power generation device 2 is located in the longitudinally extending channel portion, and the transversely extending channel portion communicates with the lower chamber 102. A single float-type power generation device 2 includes a float 8, an eccentric shaft 5 with its axis arranged transversely, a flywheel 9, and a first generator 11. The float 8 is hinged to the eccentric shaft 5 through a connecting rod 6 and a bolt 7, and is suspended below the eccentric shaft 5. The two ends of the eccentric shaft 5 are rotatably mounted on the inner wall of the channel 32 through bearing seats. The flywheel 9 is fixedly mounted on one end of the eccentric shaft 5, and the outer edge of the flywheel 9 is a large gear. Vertical slide rails 23 are installed on both sides of the longitudinally extending channel 32, perpendicular to the direction of incident wave propagation. Pulleys 24 are mounted on both sides of the float 8 via pulley connecting pins 25, thus forming a heave guide mechanism with the slide rails 23. This ensures that the float 8 can only reciprocate vertically along the slide rails 23 under wave action. The first generator 11 is fixed inside the channel 32 by a bracket. A small gear 10 is mounted on its drive shaft 13, meshing with the large gear of the flywheel 9 to form a speed-changing gear set. The first generator 11 includes a motor housing 12, a drive shaft 13, magnetic poles 14, a rotor 15, brushes 16, slip rings 17, and a junction box 18. The symmetrically arranged float-type power generation device captures wave energy while simultaneously consuming and reflecting a portion of it, thereby reducing the wave height and wave energy directly impacting the OWC chamber, effectively reducing structural load, and improving the overall device's survivability and service life under harsh sea conditions. In the energy conversion path, through the transmission design of "eccentric shaft-flywheel-speed gear set", the intermittent and variable mechanical energy generated by the reciprocating motion of float 8 is converted into stable and high-speed unidirectional rotational mechanical energy, thereby improving the power generation efficiency and power quality of the first generator 11.

[0029] The oscillating water column generator 3 includes a rotating impeller 21, a second generator 22, and a support frame 20. Both the rotating impeller 21 and the second generator 22 are fixed to the outer casing 19 via the support frame 20 and are positioned as a whole at the air vent 31. The float-type generator 2 and the oscillating water column generator 3 work together to achieve the division of labor in capturing and coordinating the conversion of wave energy at different frequencies, effectively broadening the operating frequency band of the device and improving the overall power generation efficiency and adaptability under complex sea conditions.

[0030] The energy storage device 4 is installed in the bottom cavities on the wave-facing and wave-avoiding sides of the OWC enclosure 1. In this embodiment, the energy storage device 4 uses a supercapacitor to adapt to the instability of wave energy and the need for rapid charging and discharging. The energy storage device 4 includes a current integrator, whose input terminal is connected via cables to the junction box 18 of the first generator 11 and the output terminal of the second generator 22, respectively, and whose output terminal is connected to the supercapacitor. The supercapacitor, in conjunction with the current integrator, can smooth out the power output fluctuations caused by wave irregularities in the two power generation devices, achieving efficient energy storage and smooth output, thereby improving the quality of the final output power.

[0031] Working principle:

[0032] When the wave arrives, the energy is captured by two parts of the device simultaneously: when the wave acts on the oscillating water column generator, the seawater enters the OWC chamber 30 through the bottom opening of the lower chamber 102, pushing the water inside the OWC chamber 30 to move up and down, squeezing the gas inside the upper chamber 101 to flow to the air hole 31. The gas flows through the air hole 31, thereby driving the rotating impeller 21 to rotate, converting the kinetic energy of the high-speed air into mechanical energy. The rotating impeller 21 coaxially transmits the mechanical energy to the oscillating water column generator 22, and converts the mechanical energy into electrical energy. Finally, the current is integrated into stable DC power by the current integrator and stored in the energy storage device 4.

[0033] Simultaneously, when waves act on the float-type power generation device, seawater rushes into the channels 32 on both sides. The water surface in the channels 32 rises and falls with the waves, pushing the float 8 in the channels 32 to move up and down along the slide rail 23. The vertical mechanical energy of the float 8 is converted into the rotational mechanical energy of the eccentric shaft 5 via the connecting rod 6. The flywheel 9 is fixedly installed on the eccentric shaft 5. The large gear and small gear 10 on the flywheel 9 mesh to form a speed-changing gear set, which converts the rotational motion of the eccentric shaft 5 into unidirectional, stable, and rapid rotational mechanical energy of the transmission shaft 13. The transmission shaft 13 drives the rotor 15 and slip ring 17 in the first generator 11 to rotate coaxially. Since the magnetic field directions of the magnetic poles 14 on both sides are opposite, when the rotor 15 rotates, its coil cuts the magnetic field lines to generate an induced current. This current is led out through the brush 16 and slip ring 17, and then output through the junction box 18. Furthermore, the commutator structure of slip ring 17 can automatically switch the contact points of brush 16 when the direction of the coil magnetic field changes, so that the output current direction remains consistent, thereby generating direct current. Junction box 18 transmits the generated electrical energy to energy storage device 4 via current integrator.

[0034] like Figure 8As shown, the core advantage of the device of this invention lies in the adjustable natural frequency of the water within the OWC chamber 30. Assuming the water within the OWC chamber 30 is an incompressible fluid, when it moves within the OWC chamber 30, it follows the law of conservation of mass flow rate—the mass flow rates of the fluid in the upper chamber 101 and the lower chamber 102 are always equal (the principle of continuity). The formula for calculating the mass flow rate is: ,in, It is the density of seawater. The cross-sectional area through which the fluid flows. Let be the fluid velocity at the corresponding cross-section. Substituting the horizontal cross-sectional areas and velocities of the upper and lower chambers into the formula, we obtain: After sorting, we get: ,in, It's about time. The function, It is about The first derivative is the velocity of the water in the upper chamber. It is the side length of the horizontal cross-section of the upper chamber. It is the side length of the horizontal cross-section of the lower chamber. This is the velocity of the fluid flowing through the lower chamber. The general formula for kinetic energy is... ,in, For the mass of the object, Let be the velocity of the object. The kinetic energies of the upper and lower chambers are respectively: , Summing the two formulas above and rearranging them, we obtain the total kinetic energy of the water in the OWC chamber: ,in, It is the mass of the water in the upper chamber. It is the mass of the water in the lower chamber. It is the effective height below the water surface in the upper chamber. This is the effective height of the lower chamber. The water in the upper chamber undergoes vertical displacement. At that time, its equivalent centroid displacement is The formula for calculating gravitational potential energy is: Therefore, the gravitational potential energy of the upper chamber is: ,in, It is gravitational acceleration. The formulas for the total kinetic energy of the water in the OWC chamber and the gravitational potential energy of the upper chamber are adjusted with respect to time. Taking the derivative, we obtain the corresponding frequency formula: , .according to It can be seen that the inertial force can be obtained from the above formulas for kinetic energy frequency and potential energy frequency. and resilience and on inertial force Perform linearization and ignore higher-order small terms. : , Finally, let's assume a simple harmonic motion: ,in, It is a complex amplitude. If it is frequency, then the amplitude of the inertial force is... and restoring force amplitude They are respectively: , The natural frequency formula of the water in the chamber is obtained based on the force balance equation: As shown in the above formula, and When fixed, by changing or The magnitude of the water body changes its natural frequency. When decreasing, Decrease; when When increasing, It will also decrease.

[0035] like Figures 9 to 10 As shown, a single device can be arranged in an array as a basic unit. Multiple devices can be arranged in a close array to form a continuous breakwater, or in a spaced array to cover a wider sea area. Within the array, devices with different... or The units form a "wideband wave-absorbing array", which can efficiently capture wave energy across the entire spectrum from shortwave to longwave, improve the overall efficiency and economic benefits of wave energy power plants, and realize the dual functions of large-scale wave energy power generation and coastal protection.

Claims

1. An integrated float-driven and oscillating water column synergistic wave energy generation device, characterized in that, The device includes an oscillating water column tank (1) with an internal oscillating water column chamber (30), an air hole (31) located at the center of the top of the oscillating water column tank (1), an oscillating water column type power generation device (3) placed in the air hole (31), a float type power generation device (2) located in the oscillating water column tank (1), and an energy storage device (4) located in the oscillating water column tank (1) and on both sides of the oscillating water column chamber (30); the float type power generation device (2) includes an eccentric shaft (5) with its axis arranged laterally, a float (8) connected to the eccentric shaft (5), a flywheel (9) arranged coaxially with the eccentric shaft (5), and a first generator (11) with a gear drive perpendicular to the flywheel (9); The oscillating water column chamber (30) includes an upper chamber (101) and a lower chamber (102). The horizontal cross-sectional area of ​​the upper chamber (101) is larger than that of the lower chamber (102). The two side walls of the lower chamber (102) are respectively provided with channels (32) extending upward to the top of the box body (1). The bottom of the channel (32) is connected to the lower chamber (102). The bottom of the lower chamber (102) penetrates the oscillating water column box body (1). The float (8) is located in the channel (32) and suspended below the eccentric shaft (5). The oscillating water column power generation device (3) includes a second generator (22) and a rotating impeller (21) coaxially arranged with the second generator (22).

2. The integrated float-driven and oscillating water column synergistic wave energy generation device according to claim 1, characterized in that, The energy storage device (4) is electrically connected to the oscillating water column power generation device (3) and the float power generation device (2).

3. The integrated float-driven and oscillating water column synergistic wave energy generation device according to claim 1, characterized in that, The upper chamber (101) has a large square horizontal cross-section with a side length of [missing information]. The horizontal cross-section of the lower chamber (102) is a small square with a side length of . .

4. The integrated float-driven and oscillating water column synergistic wave energy generation device according to claim 1, characterized in that, The structure of the oscillating water column chamber (30) is designed based on the Helmholtz resonance principle, and the lower chamber (102) is a slender pipe structure.

5. The integrated float-driven and oscillating water column synergistic wave energy generation device according to claim 1, characterized in that, The float-type power generation device (2) and the channel (32) are both provided in twos, and are symmetrically arranged on the left and right sides perpendicular to the direction of incident wave propagation.

6. The integrated float-driven and oscillating water column synergistic wave energy generation device according to claim 1, characterized in that, The flywheel (9) has a large gear on its outer edge, which meshes perpendicularly with the small gear (10).

7. The integrated float-driven and oscillating water column synergistic wave energy generation device according to claim 1, characterized in that, The energy storage device (4) is installed in the bottom cavity of the wave-facing side and the wave-repellent side of the oscillating water column tank (1).

8. The integrated float-driven and oscillating water column synergistic wave energy generation device according to claim 1, characterized in that, The pores (31) are circular.

9. The integrated float-driven and oscillating water column synergistic wave energy generation device according to claim 1, characterized in that, The horizontal cross-sectional side length of the lower chamber (102) As the volume decreases, the natural frequency of the water inside the oscillating water column chamber (30) decreases.

10. The integrated float-driven and oscillating water column coordinated wave energy generation device according to claim 1, characterized in that, The formula for the natural frequency is as follows: ,in, It is gravitational acceleration. It is the effective height below the water surface in the upper chamber. It is the effective height of the lower chamber; , , Fixed and unchanging, The larger the value, the smaller the natural frequency.

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