A wave energy power generation water seal damping system

Abstract

This invention discloses a wave energy power generation water-sealed damping system, including a float, a damper, a guide shaft, a limiting assembly, and a damping water tank. The float floats on the water surface, and the guide shaft is fixed to the lower end of the float. The damper is located below the float and suspended in the water, and is mounted on the guide shaft, allowing it to slide up and down. The limiting assembly consists of an upper limiting assembly and a lower limiting assembly, respectively located above and below the damper, limiting the upper and lower sliding positions of the damper. The damping water tank consists of an upper damping water tank and a lower damping water tank, corresponding to and cooperating with the upper and lower limiting assemblies, respectively. When the damper slides upward, the upper limiting assembly acts on the upper damping water tank to buffer the upward collision force; when the damper slides downward, the lower limiting assembly acts on the lower damping water tank to buffer the downward collision force. This invention can weaken or even eliminate direct collisions between moving mechanisms, improve the continuity of wave capture device operation, enhance the reliability of the wave energy power generation system, and improve energy conversion efficiency.

Description

Technical Field

[0001] This invention relates to the field of damping and vibration reduction technology for preventing mechanical collisions, specifically a water-sealed damping system for preventing direct collisions between moving mechanisms during wave energy generation. Background Technology

[0002] Wave energy generation devices can generally be divided into three types in terms of structure: oscillating water column type, oscillating float type, and wave-top type. Among them, the oscillating float type is the most widely used wave energy generation technology. It uses an oscillating float as a capture device to absorb wave energy. It can be in the form of a single float, double float, or even multiple floats. Then, it uses different energy conversion strategies such as hydraulic, pneumatic, and direct drive to convert the captured energy into electrical energy output by the generator.

[0003] In wave energy generation, collisions between moving structures are inevitable in order to confine the movement of the floating body within a certain range. These collisions disrupt the original oscillating motion, resulting in a period where the body cannot absorb wave energy and loses its ability to capture wave energy, severely hindering the improvement of wave energy generation efficiency. Furthermore, these collisions are a major destructive force on wave energy generation devices. Therefore, it is essential to take technical measures to weaken or eliminate these motion collisions, which can effectively improve the continuity of the capture device's operation, enhance the reliability of the wave energy generation system, and improve energy conversion efficiency.

[0004] Currently, the primary collision avoidance method for oscillating buoy-type wave energy generation scenarios is the use of hydraulic dampers. This involves installing a hydraulic damping system near the collision point, utilizing the buffering effect of hydraulic pressure to reduce impact and prevent the relatively moving structure from directly colliding with pre-set mechanical limiting devices. However, hydraulic damping systems are costly, structurally complex, and inconvenient to install and maintain. Furthermore, the concentrated force of the hydraulic system can easily cause excessive localized stress on the structure, even tearing welds, resulting in low reliability in wave energy generation scenarios where collisions are frequent. Additionally, hydraulic systems are prone to oil leaks, causing pollution to the marine environment. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention proposes a wave energy power generation water seal damping system, which weakens or even eliminates direct collisions between moving mechanisms, improves the continuity of the capture device's operation, enhances the reliability of the wave energy power generation system, and improves energy conversion efficiency.

[0006] The technical solution of the present invention is as follows:

[0007] A wave energy power generation water-sealed damping system mainly includes a float, a damping body, a guide shaft, a limiting assembly, and a damping water tank. Specifically:

[0008] The float is on the water surface, and the guide shaft is fixed to the lower end of the float.

[0009] The damping body is located below the float and is suspended in the water. It has a central opening and is mounted on a guide shaft via a rolling bearing, allowing it to slide up and down on the guide shaft.

[0010] The limiting assembly consists of an upper limit assembly and a lower limit assembly, which are respectively located above and below the damping body to limit the upper and lower limits of the sliding position of the damping body.

[0011] The damping water chamber is divided into an upper damping water chamber and a lower damping water chamber, which are respectively located above and below the damping body, and respectively cooperate with the upper limit assembly and the lower limit assembly. The damping water chamber has a water damping structure. When the damping body slides upward, the upper limit assembly acts on the upper damping water chamber, and the water damping structure buffers the upward collision force. When the damping body slides downward, the lower limit assembly acts on the lower damping water chamber, and the water damping structure buffers the downward collision force.

[0012] Preferably, the damping water tank includes a tank cylinder and a sealing plate, forming a water damping structure. One end of the tank cylinder is fixed and sealed to the float or damping body, and the other end has an opening corresponding to the position of the limiting assembly. The sealing plate is disposed inside the tank cylinder, can move up and down, and is restricted near the opening to prevent it from falling out of the tank cylinder. The diameter of the opening is larger than the outer diameter of the limiting assembly, so that the limiting assembly can act on the sealing plate.

[0013] Preferably, the water damping structure has two forms. One is that a water inlet is provided on the wall of the tank, and the water inlet is located near the opening of the tank and inside the restricted position where the water sealing plate moves to the opening of the tank. A small gap is left between the edge of the water sealing plate and the inner wall of the tank to allow a small amount of water to pass through. A stepped water-blocking structure is formed by the water inlet and the small gap. When the water sealing plate moves to the restricted position, water enters the tank from the water inlet. When the water sealing plate is pushed into the tank by the restricted position assembly, the water is gradually discharged from the water inlet, and the damping force is small. After the water sealing plate moves past the water inlet, the water can only be discharged from the small gap, and the damping becomes larger. The water sealing plate and the tank form a water tank with a larger damping force, which makes the movement speed of the water sealing plate decrease rapidly and buffers the upward and downward collision forces.

[0014] Preferably, there are multiple water inlets evenly distributed on the cylinder wall, and the size of the water inlets does not exceed one-quarter of the height of the cylinder wall.

[0015] Another type of water damping structure does not have water inlet holes in the tank wall, meaning the tank wall is sealed. Instead, a water flow gap is left between the edge of the water sealing plate and the inner wall of the tank. This water flow gap can be larger than the small gap in the previous structure. As the water sealing plate moves to the restricted position, water enters the tank through the water flow gap. When the water sealing plate is pushed into the tank by the restricted position assembly, the water gradually exits from the water flow gap, gaining damping force and causing the movement speed of the water sealing plate to decrease rapidly, buffering the upward and downward collision forces. This water damping method without water inlet holes maintains a constant water damping.

[0016] Preferably, the damping water tank is further provided with a return spring, one end of which is fixed to the end of the tank and the float or the damping body, and the other end is in contact with the water sealing plate but not fixed, so as to apply a return force to the water sealing plate.

[0017] Preferably, the water sealing plate includes a substrate and a viscoelastic material layer disposed on the inner side of the substrate. The viscoelastic material layers are spaced apart, and the surface is covered with a rigid constraint layer. The contact point with the return spring is located in the rigid constraint layer.

[0018] Preferably, the damping water tank can be arranged in at least two ways: one is to install the upper damping water tank at the bottom of the float and the corresponding upper limit assembly at the top of the damping body; the other is to install the lower damping water tank at the bottom of the damping body and the corresponding lower limit assembly at the lower end of the guide shaft.

[0019] Another method involves installing the upper damping water tank on top of the damping body, with the corresponding upper limit assembly installed at the bottom of the float; and installing the lower damping water tank at the bottom of the damping body, with the corresponding lower limit assembly installed at the lower end of the guide shaft.

[0020] Preferably, the weight of the sealing plate of the lower damping water tank is designed to be greater than the buoyancy. When the upper damping water tank is installed at the bottom of the float, the weight of its sealing plate is designed to be greater than the buoyancy. When the upper damping water tank is installed at the top of the damping body, the buoyancy of its sealing plate is greater than the weight.

[0021] Preferably, the limiting assembly consists of several annularly arranged triangular ribs, fixed to the damping body or float. The side of the limiting assembly that contacts the water sealing plate is provided with a viscoelastic material layer and covered with a rigid constraint layer.

[0022] Compared with the prior art, the advantages of this invention are as follows:

[0023] 1. This invention utilizes seawater as a force transmission medium, so that the impact load is evenly distributed at the bottom of the structure. At the same time, as the seawater in the damping tank is discharged at high speed from the water inlet or gap under the high pressure of the impact, it carries away part of the impact energy and plays a role in buffering the impact, thereby overcoming the problem of stress concentration in hydraulic dampers.

[0024] 2. Furthermore, the present invention configures a viscoelastic material layer inside the water sealing plate, which can effectively suppress high-frequency vibration after impact, block the transmission of secondary vibration after structural collision, improve the fatigue resistance of the welded parts, and make the entire system have better stability and reliability.

[0025] 3. At the same time, the water seal damping system described in this invention does not have the problem of medium leakage, which is conducive to the protection of the marine ecological environment.

[0026] In summary, this water-sealed damping system has a simple structure and low cost. It directly uses seawater as the medium for force transmission, requires no daily maintenance, has no risk of leakage, can reduce or even eliminate direct collisions between moving mechanisms, improve the continuity of wave capture device operation, enhance the reliability of wave energy power generation system, and improve energy conversion efficiency. It is an environmentally friendly technology utilization method. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the overall structure of the wave energy power generation water seal damping system provided in Embodiment 1 of the present invention;

[0028] Figure 2 This is a schematic diagram of the water seal damping system described in this invention;

[0029] Figure 3 This is a schematic cross-sectional view of the water seal damping system described in this invention;

[0030] Figure 4 This is a schematic diagram of the upper limit assembly described in this invention;

[0031] Figure 5 This is a schematic diagram of the overall structure of the wave energy power generation water seal damping system provided in Embodiment 2 of the present invention. Detailed Implementation

[0032] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings and embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present invention. It should be noted that, unless otherwise specified, the features in the embodiments of the present invention can be combined with each other.

[0033] The floating body of the wave energy power generation device oscillates back and forth under the action of waves. When the sea conditions are relatively bad, it is necessary to limit the movement of the floating body to prevent excessive waves from damaging the energy conversion system and to protect the safety of components such as the PTO system and generator.

[0034] Example 1:

[0035] See Figure 1 The wave energy power generation water seal damping system provided in this embodiment mainly includes a float 1, a damping body 2, a guide shaft 3, an upper limit assembly 4, a lower limit assembly 5, an upper damping water tank 61, a lower damping water tank 62, and a rolling bearing 7.

[0036] The guide shaft 3 is fixed to the bottom of the float 1. The damping body 2 is located below the float 1 and can be suspended in the water. It has an opening in the middle and is mounted on the guide shaft 3 through a rolling bearing 7, and can slide up and down along it. The upper limit assembly 4 is fixed to the damping body 2 and the rolling bearing 7, and the lower limit assembly 5 is fixed to the lower end of the guide shaft 3. The upper limit assembly 4 and the lower limit assembly 5 are located on the upper and lower sides of the damping body 2, respectively.

[0037] The bottom of float 1 is equipped with an upper damping water tank 61, and the bottom of damping body 2 is equipped with a lower damping water tank 62. The two damping water tanks have the same structure. Here, the upper damping water tank 61 is used as an example. See [link to relevant documentation]. Figure 2 The upper damping water tank 61 includes a return spring 611, a water inlet 612, a tank cylinder 613, and a water sealing plate 614, forming a water damping structure. Specifically, one end of the tank cylinder 613 is fixed and sealed to the float 1, while the other end has an opening corresponding to the upper limit assembly 4 at the top of the damping body 2. The water sealing plate 614 is disposed inside the tank cylinder 613, with its edge fitting a small gap with the inner wall of the tank cylinder 613, allowing a small amount of water to pass through. This, combined with the design of the water inlet of the tank cylinder, forms a stepped water-blocking structure, with initially low damping that increases after passing the water inlet. The water sealing plate 614 can move up and down and is restricted near the opening without detaching from the tank cylinder 613. Furthermore, the diameter of the opening is larger than the outer diameter of the upper limit assembly 4, allowing the upper limit assembly 4 to act on the water sealing plate 614. A water inlet hole 612 is provided on the wall of the silo 613, and the water inlet hole 612 is located near the opening of the silo and inside the restricted position where the sealing plate moves to the opening of the silo.

[0038] See Figure 3 One side of the return spring 611 is fixed to the bottom of the float 1, and the other side is in contact with but not fixed to the water sealing plate 614. The water sealing plate 614 includes a substrate, a viscoelastic material layer 6141 and a rigid constraint layer 6142. The viscoelastic material layer 6141 is distributed in a ring at intervals inside the substrate as an intermediate layer. Its surface is covered by the rigid constraint layer 6142, and the contact point with the return spring 611 is located on the rigid constraint layer.

[0039] The upper and lower limit assemblies 4 and 5 have the same structure, see [link / reference]. Figure 4 Taking the upper limit assembly 4 as an example, its contact surface is provided with a viscoelastic material layer 41 distributed at intervals, and is covered by a rigid constraint layer 42.

[0040] In addition, the length of the rolling bearing 7 is greater than the sum of the heights of the damping body 2 and the upper limit assembly 4.

[0041] The number of return springs 611 and water inlet holes 612 can be multiple. The size of the water inlet holes 612 should preferably not exceed one-quarter of the height of the tank 613 to ensure the space for forming a closed water tank. In addition, the return spring 611 is preferably a compression spring with low stiffness, which only provides the restoring force to return the sealing plate to its original position.

[0042] In addition, in order to effectively limit the water sealing plate, a baffle is provided at the opening of the silo 613 to ensure that the water sealing plate 614 does not fall out of the silo 613 and that the water sealing plate 614 always moves within the damping water silo.

[0043] Of course, the damping water tank 61 can also be designed without an inlet hole, and the water sealing plate 614 and the tank 613 can be designed with a certain water flow gap, so that seawater can pass through the gap. In this way, when the water sealing plate 614 returns to the opening, seawater can enter the tank through the water flow gap. When the water sealing plate 614 is squeezed and moves into the tank, seawater can be discharged through the water flow gap, thus obtaining a certain water damping. However, unlike the previous structure, the water damping of this method without an inlet hole is constant.

[0044] Alternatively, a return spring may not be installed inside the damping water tank. Instead, depending on the installation position of the damping water tank, the weight of the sealing plate itself may be designed to be greater than the buoyancy, or the buoyancy of the sealing plate itself may be greater than the weight, so that the sealing plate can return to its original position by its own weight or buoyancy.

[0045] The wave energy generation water seal damping system shown in this embodiment operates as follows:

[0046] Float 1 and damper 2 oscillate irregularly simultaneously under the action of waves. When float 1 and damper 2 approach each other, the upper limit assembly 4 connected to damper 2 collides with the water-sealing plate 614 at the bottom of float 1. This causes the water-sealing plate 614 to move upward and compress the seawater in the upper damping tank 61. The high-frequency secondary vibration generated by the initial collision is dissipated by the viscoelastic material layer 6141 in the water-sealing plate 614 and is not transmitted to float 1. At this time, the seawater in the upper damping tank 61 is mainly squeezed out of the tank at high speed through the inlet hole 612. The high-speed outflow of seawater carries away some of the impact energy, thus producing a buffering effect and appropriately slowing down the movement speed of the water-sealing plate 614. When the sealing plate 614 moves above the water inlet 612, the sealing plate 614, the tank 613, and the bottom of the float 1 will form a water tank with a greater degree of sealing. When the sealing plate 614 moves upward, the seawater in the water tank can only flow out from the tiny gaps around the sealing plate 614, which will create greater damping and cause the movement speed of the sealing plate 614 to drop rapidly. The process of seawater flowing out from the gaps in the water tank is also a process of dissipating collision energy, thereby achieving the purpose of dispersing load and soft contact.

[0047] When the upper limit assembly 4 leaves the water sealing plate 614, the water sealing plate 614 returns to its original position under its own weight or in conjunction with the return spring 611. The seawater inside the upper damping water tank 61 is quickly replenished through the water inlet 612, preparing for the next cycle.

[0048] When the float 1 and the damper 2 move away from each other under the action of waves, the lower limit assembly 5 connected to the lower end of the guide shaft 3 collides with the sealing plate of the lower damping water tank 62 at the bottom of the damper 2, causing the sealing plate to move upward and compress the seawater in the lower damping water tank 62. The subsequent operation of the water seal damping system is the same as described above, until the sealing plate returns to its original position.

[0049] Example 2:

[0050] like Figure 5 As shown, this embodiment differs from Embodiment 1 in that the upper damping water tank 61 is installed on top of the damping body 2, and the corresponding upper limit assembly 4 is installed at the bottom of the float 1. The installation positions of the lower damping water tank 62 and the lower limit assembly 5 are the same as in Embodiment 1.

[0051] Work process:

[0052] Float 1 and damper 2 oscillate irregularly simultaneously under the action of waves. When float 1 and damper 2 approach each other, the upper limit assembly 4 connected to the bottom of float 1 collides with the water-sealing plate 614 at the top of damper 2. This causes the water-sealing plate 614 to move downwards, compressing the seawater in the damping tank 61. The high-frequency secondary vibration generated by the initial collision is dissipated by the viscoelastic material layer 6141 in the water-sealing plate 614 and is not transmitted to float 1. At this time, the seawater in the damping tank 61 is mainly squeezed out of the tank at high speed through the inlet hole 612, carrying away some of the impact energy and producing a buffering effect, thus slowing down the movement speed of the water-sealing plate 614. When the water sealing plate 614 moves below the water inlet 612, the top of the water sealing plate 614, the annular guard plate 613, and the damping body 2 will form a water tank with a greater degree of sealing. When the water sealing plate 614 moves downward, the seawater in the water tank can only flow out from the gaps around the water sealing plate 614, which will form greater damping and cause the movement speed of the water sealing plate 614 to drop rapidly. The process of seawater flowing out from the gaps in the water tank is also the process of dissipating collision energy, thereby achieving the purpose of dispersing load and soft contact.

[0053] In this embodiment, the water sealing plate 614 can be designed with buoyancy slightly greater than gravity. When the limiting assembly 4 leaves the water sealing plate 614, the water sealing plate 614 returns to its original position under its own buoyancy or under the combined action of the return spring 611. The seawater inside the damping water tank 61 is quickly replenished through the water inlet 612, so as not to form a cavity.

[0054] When the float 1 and damper 2 move away from each other under the action of waves, the lower limit assembly 5 connected to the guide shaft 3 collides with the sealing plate of the damping water tank 62 at the bottom of the damper 2. This causes the sealing plate to move upward, compressing the seawater in the damping water tank 62. The high-frequency secondary vibration generated by the initial collision is dissipated by the viscoelastic material layer in the sealing plate and is not transmitted to the float 1. At this time, the seawater in the damping water tank 62 is mainly squeezed out of the tank at high speed through the inlet, carrying away some of the impact energy and producing a buffering effect, thus slowing down the movement speed of the sealing plate. When the sealing plate moves above the inlet, the sealing plate, the tank cylinder, and the bottom of the damper 2 will form a water tank with a greater degree of sealing. When the sealing plate moves upward again, the seawater in the tank will create greater damping, causing the movement speed of the sealing plate to decrease rapidly.

[0055] When the lower limit assembly 5 leaves the water sealing plate, the water sealing plate returns to its original position under its own weight or in conjunction with the return spring. The seawater inside the damping water tank 62 is quickly replenished through the water inlet hole, preventing the formation of a cavity.

[0056] In summary, the wave energy power generation water seal damping system of the present invention can reduce or even eliminate direct collisions between moving mechanisms, improve the continuity of operation of the capture device, enhance the reliability of the wave energy power generation system, and improve energy conversion efficiency.

Claims

1. A wave energy power generating water seal damping system, characterised in that, The device comprises a floating body, a damping body, a guide shaft, a limiting assembly and a damping water tank. The floating body floats on the water surface, and the guide shaft is fixed to the lower end of the floating body. The damping body is located below the floating body and suspended in the water, with a central hole and installed on the guide shaft through a rolling bearing, and can slide up and down. The limiting assembly comprises an upper limiting assembly and a lower limiting assembly, which are respectively arranged above and below the damping body to limit the upper limit position and the lower limit position of the damping body. The damping water tank comprises an upper damping water tank and a lower damping water tank, which are respectively arranged above and below the damping body and correspondingly matched with the upper limiting assembly and the lower limiting assembly. The damping water tank has a water damping structure, and when the damping body slides upward, the upper limiting assembly acts on the upper damping water tank to buffer the upward collision force, and when the damping body slides downward, the lower limiting assembly acts on the lower damping water tank to buffer the downward collision force. The damping water tank comprises a tank barrel and a water sealing plate, which constitute the water damping structure.

2. A wave energy power generating water seal damping system according to claim 1, characterised in that: One end of the tank barrel is fixed and sealed with the floating body or the damping body, and the other end has an opening and corresponds to the position of the limiting assembly.

3. The wave energy power generating water seal damping system according to claim 1, characterized in that: The water sealing plate is arranged in the tank barrel and can move up and down, and is limited near the opening and does not come out of the tank barrel.

4. A wave energy power generating water seal damping system according to any one of claims 1 to 3, characterised in that: The opening diameter is larger than the outer diameter of the limiting assembly, so that the limiting assembly can act on the water sealing plate.

5. A wave energy power generating water seal damping system according to claim 4, characterised in that: The tank barrel wall is provided with a water inlet hole, which is located on the side close to the opening of the tank barrel and inside the limited position of the water sealing plate moving to the opening of the tank barrel. A small gap is left between the edge of the water sealing plate and the inner wall of the tank barrel for a small amount of water flow. The water inlet hole and the small gap form a stepped water blocking structure. When the water sealing plate moves to the limited position, water enters the tank barrel from the water inlet hole. When the water sealing plate is pushed by the limiting assembly and moves to the tank barrel, water gradually flows out of the water inlet hole, obtaining damping force with smaller damping. When the water sealing plate moves beyond the water inlet hole, water can only flow out of the small gap, and the damping becomes larger. The water sealing plate and the tank barrel form a water tank with larger damping force, so that the movement speed of the water sealing plate rapidly decreases, buffering the upward and downward collision force. The water inlet hole is uniformly distributed on the barrel wall, and the size of the water inlet hole is not more than one fourth of the height of the barrel wall. The tank barrel wall is provided with a water inlet hole, which is located on the side close to the opening of the tank barrel and inside the limited position of the water sealing plate moving to the opening of the tank barrel. A small gap is left between the edge of the water sealing plate and the inner wall of the tank barrel for a small amount of water flow. The water sealing plate and the tank barrel form a water tank with larger damping force, so that the movement speed of the water sealing plate rapidly decreases, buffering the upward and downward collision force. The damping water tank is further provided with a reset spring. One end of the reset spring is fixed to the end of the tank barrel fixed with the floating body or the damping body, and the other end is in contact with the water sealing plate but not fixed, applying a reset force to the water sealing plate. The water sealing plate comprises a base plate and a layer of viscoelastic material arranged on the inner side of the base plate. The viscoelastic material layer is spaced and coated with a rigid restraint layer. The contact point of the reset spring is located on the rigid restraint layer.

6. The wave energy power generating water seal damping system according to claim 4, characterized in that: The upper damping water tank can be installed at the bottom of the floating body, and the upper limiting assembly corresponding thereto is installed at the top of the damping body; the lower damping water tank is installed at the bottom of the damping body, and the lower limiting assembly corresponding thereto is installed at the lower end of the guide shaft.

7. The wave energy power generating water seal damping system according to claim 4, characterized in that: The upper damping water tank can be installed at the top of the damping body, and the upper limiting assembly corresponding thereto is installed at the bottom of the floating body; the lower damping water tank is installed at the bottom of the damping body, and the lower limiting assembly corresponding thereto is installed at the lower end of the guide shaft.

8. The wave energy power generating water seal damping system according to claim 4, characterized in that: The gravity of the water sealing plate of the lower damping water tank is designed to be greater than the buoyancy, the gravity of the water sealing plate of the upper damping water tank is designed to be greater than the buoyancy when the upper damping water tank is installed at the bottom of the floating body, and the buoyancy of the water sealing plate of the upper damping water tank is greater than the gravity when the upper damping water tank is installed at the top of the damping body.

9. The wave energy power generating water seal damping system according to claim 4, characterized in that: The limiting assembly is composed of a plurality of annularly arranged triangular structure rib plates, is fixed to the damping body or the floating body, and is provided with a viscoelastic material layer on the contact surface with the water sealing plate and is coated with a rigid constraint layer.

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