Wave power generation unit and wave power generation system

Abstract

To provide a wave power generation unit having a configuration suitable for executing wave power generation in waters such as ocean areas where impact of breaking waves is less, that is, offshore, and a wave power generation system.SOLUTION: A wave receiving bucket 32P1 submerged at a first position P1 has a wave receiving surface 32b facing downward when a floater 2 is floating on a water surface 100, and an upward relative water flow 103a acts toward the wave receiving surface 32b, to push the wave receiving bucket 32P1 at the first position P1 relatively upward, causing a rotation body part 31 and a rotation shaft 33 to rotate in a forward direction (a solid arrow direction in Fig.5). Consequently, the wave receiving bucket 32P1 submerged at the first position P1 is suitable for converting the relative water flow 103a, which acts as an upward external force, into rotational motion of the rotation shaft 33 of the wave receiving rotor 3.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a wave power generation unit and a wave power generation system that can generate power using the force of waves generated offshore. [Background technology]

[0002] Various proposals have been made in the past regarding wave power generation systems that generate electricity using wave power and wave power generation units used in such systems. For example, Patent Document 1 proposes a wave energy conversion system that uses a turbine with rotatable blades that are appropriately designed to convert the water flow of breaking waves generated on the coast into electricity, and a wave energy conversion unit that is used in this system.

[0003] This system and unit uses multiple wave energy conversion units installed on or near the shoreline to capture water currents caused by ocean waves approaching the shoreline. Ocean waves are waves that arise on the ocean surface as small wind waves (ripples) are generated by the frictional force of wind blowing over the water surface, and gradually grow as they absorb energy from the wind.

[0004] According to Patent Document 1, the wave energy conversion unit is installed near the coast in an area with an average water depth of approximately 1 to 5 m, and the waves on the coastline generate fast horizontal water currents that repeatedly flow toward and away from the land. Note that the coast refers to the boundary area between the sea and the land, and the coastline refers to the boundary line between the sea and the land.

[0005] Furthermore, according to the ocean wave theory described in Patent Document 1, when ocean waves approach the coast, the boundary between the water surface and the slope of the seabed narrows, so that the wave energy is concentrated near the surface, causing the wave height to increase and eventually reach a critical point and break. It also states that just before the waves break, in typical wave conditions (several meters high), the water flow speed in the direction facing the coast reaches approximately 5 to 10 m / s, and therefore electricity can be generated by placing a rotating turbine in this water flow.

[0006] Here, waves that break as they approach the shore are called "breaking waves." Such breaking waves occur when waves move from deep offshore waters into shallow waters, and as the water depth decreases, the wave height increases, the crests become pointed, the troughs become flat, and finally, when the wave height approaches the water depth, the wave breaks in the direction of its travel and breaks.

[0007] The sea area from the offshore position where such breaking waves begin to occur to the shoreline is called the "surf zone." Because the energy generated by breaking waves in this surf zone is extremely large, many power generation systems that utilize the horizontal flow of breaking waves have been proposed in addition to the one described in Patent Document 1. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] JP 2017-521599 A Summary of the Invention [Problem to be solved by the invention]

[0009] However, breaking waves that occur on the coastline or in areas close to the coastline generate large impact forces (also called impact wave breaking force or impact wave pressure) when they collide with objects, and these collisions occur frequently, so installing wave power generation units such as wave energy conversion units poses the problem that the units may be damaged or malfunction due to the impact forces of breaking waves.

[0010] In contrast, ocean waves that occur offshore, such as deep water waves, are caused by circular motion of seawater fluid particles moving in a circular motion, which results in water movement and currents not only horizontally but also vertically, and behaves differently from coastal waters such as surf zones or waters close to the coast, where horizontal water movement is the main force. In other words, deep water waves are external gravity waves that occur on the surface of water that is sufficiently deep compared to their wavelength.

[0011] Theoretically, in areas where deep water waves occur, where the water depth h is very large compared to the wave wavelength λ (h≫λ), the fluid particles in the deep water waves will move in a circular motion, and in shallower areas, for example, areas where shallow water waves occur, where the water depth h is smaller than the wave wavelength λ (h<λ), the fluid particles in the shallow water waves will move in an extremely flattened elliptical motion, and the entire water from the surface to the bottom will move very little in the vertical direction, i.e., it can be approximated as moving almost only horizontally.

[0012] On the other hand, as the water depth h approaches infinity relative to the wave wavelength λ, the motion of the fluid particles in the waves changes from an extremely flattened elliptical motion to an elliptical motion in which the vertical minor axis gradually becomes larger than the horizontal major axis, becoming closer to a circular motion, resulting in a motion that involves vertical motion and behaves differently from motion that moves only horizontally. In other words, offshore ocean waves do not consist of water moving only horizontally, but also water moving vertically.

[0013] When waves approach the shore from offshore, the change in water depth due to the slope of the bottom causes the wave height to increase while the wavelength of the wave shortens. This change in waveform due to the change in water depth is called "shallowing." After this "shallowing" process, when the wave height finally approaches the water depth, the wave breaks in the direction of its travel, causing the wave to break. Generally, this "shallowing" process occurs in waters where the water depth h is shallower than half the wave wavelength λ (h<λ / 2), and it is said that breaking also occurs as a secondary phenomenon.

[0014] Therefore, in this application, for the sake of convenience, we define "offshore" as waters deeper than the area where "shallow water deformation" occurs, and propose a wave power generation unit that can generate electricity using wave power in such offshore areas, as well as a wave power generation system that uses this wave power generation unit.

[0015] In other words, the present invention has been made to solve the above-mentioned problems, and proposes a wave power generation unit and wave power generation system having a configuration suitable for carrying out wave power generation in waters such as ocean areas where the impact of breaking wave impact forces is small, i.e., offshore.As a result, the effects of breaking wave impact forces caused by the wave-breaking phenomenon can be avoided, and damage to the wave power generation unit caused by such breaking wave impact forces can also be reduced.

[0016] In this application, the ocean is mainly used as an example of the water area to which the present invention is applicable; however, the water area to which the present invention is applicable is not necessarily limited to the ocean, and may include, for example, lakes, marshes, rivers, and other water areas where surface waves occur similarly to the ocean. [Means for solving the problem]

[0017] To achieve this object, the wave power generation unit of the first invention is for a wave power generation system that generates power using water surface waves generated on the water surface offshore, and comprises a float that can float on the water surface where water surface waves are generated by buoyancy and moves in each axis direction of a spatially fixed coordinate system in response to the water surface waves and rotates around each axis, thereby swaying and oscillating freely on the water surface; a rotating main body that is rotatably supported by the float via a rotating shaft and is integrated with the rotating shaft; a plurality of wave receiving buckets provided on the entire outer periphery of the rotating main body; and a wave receiving member formed on each of the wave receiving buckets that receives the water surface waves. The wave-receiving rotor is formed in a waterwheel-like shape having a wave-receiving surface and uses the rotation of the rotating shaft to rotate the rotor part of the generator. When the float is floating on the water surface, at least a portion of the multiple wave-receiving buckets are submerged in water, and the wave-receiving buckets in the submerged part receive the relative water flow generated in the water at their wave-receiving surfaces at a first position where the wave-receiving surface faces downward, and at a second position rotated from the first position around the axis of the rotating shaft where the wave-receiving surface faces sideways, thereby applying a rotational force to the rotating main body part.

[0018] Here, the space-fixed coordinate system is a three-dimensional Cartesian coordinate system XYZ whose origin is fixed in space such as the earth's surface, and is also called a space coordinate system or a ground-fixed coordinate system.

[0019] Furthermore, the rotation axis of the wave receiving rotor is the rotation axis of the entire wave receiving rotor and also the rotation axis of the rotating main body of the wave receiving rotor. The axis center of this rotation axis (center of the shaft) is also the center of the circular orbit of the multiple wave receiving buckets and the rotation center of the rotating main body. The generator is a device that converts the rotation of the rotor part into electrical energy.

[0020] Additionally, "upward" refers to facing vertically upward (the direction opposite to the direction of the Earth's gravity, the positive direction of the Z axis of the spatially fixed coordinate system), "downward" refers to facing vertically downward (the direction of the Earth's gravity, the negative direction of the Z axis of the spatially fixed coordinate system), and "sideways" refers to facing horizontally (the direction perpendicular to the direction of the Earth's gravity, the direction parallel to the XY plane of the spatially fixed coordinate system).

[0021] Furthermore, when the wave receiving rotor rotates approximately 90° in the forward direction from the second position, the wave receiving bucket rotates to the first position. In other words, the wave receiving bucket in the first position corresponds to the wave receiving bucket in the second position having rotated approximately 90° in the forward direction around the axis of the rotation shaft of the wave receiving rotor.

[0022] Furthermore, the relative water current that occurs in the water refers to the relative water current that occurs in the water due to the cooperation of the movement of water surface waves and the rocking of the floating body caused by those water surface waves.

[0023] According to the buoyancy power generation system of the first invention, a floating body floats on the surface of a body of water, such as the ocean, by buoyancy. The floating body oscillates on the water surface due to the movement (including swaying) of water surface waves. The oscillating of the floating body is a movement along each of the X, Y, and Z coordinate axes of a spatially fixed coordinate system, and a rotation around each of these axes, and is a movement that is a combination of one or more of these movements and rotations.

[0024] The motions of such floating bodies include motion in the X-axis direction (surge, surging), motion in the Y-axis direction (sway, swaying), motion in the Z-axis direction (heave, heaving), rotational motion around the X-axis (roll, rolling), rotational motion around the Y-axis (pitch, pitching), and rotational motion around the Z-axis (yaw, yawing).

[0025] Here, when the float is floating on a horizontal water surface, at least a portion of the multiple wave-receiving buckets of the wave-receiving rotor are submerged in water, and the wave-receiving buckets in these submerged portions receive the relative water flow occurring in the water on their wave-receiving surfaces, and this relative water flow acts as an external force to push and move the wave-receiving buckets, causing the rotating main body to rotate in the forward direction together with the rotating shaft.

[0026] As the rotating body and the rotating shaft rotate in the forward direction, the multiple receiving buckets on the outer periphery of the rotating body move circularly along a circular orbit centered on the rotating shaft as the rotating body rotates, and each receiving bucket performs a series of movements in which it repeatedly passes through the first position and also the second position in turn.

[0027] The circular motion of the multiple wave receiving buckets rotates the rotating body, and when the rotating shaft rotates integrally with the rotating body, the rotation of this rotating shaft is used to rotate the rotor, which is the rotating body of the generator. This generator is mounted on a floating body, and when the rotating shaft of the wave receiving rotor rotates, the rotational force of this rotating shaft is used to rotate the rotor, thereby generating electricity.

[0028] Here, the wave receiving bucket in the submerged first position has its wave receiving surface facing downward when the float is floating on the water surface, and when a relative upward water flow acts on this wave receiving surface, the wave receiving bucket in the first position is pushed relatively upward, causing the rotating main body and rotating shaft to rotate in the forward direction.

[0029] Therefore, the wave receiving bucket in the submerged first position is particularly suitable for converting a relative water flow that acts an external force upward, rather than a relative water flow that acts an external force in a lateral direction, into rotational motion of the rotation axis of the wave receiving rotor.

[0030] For example, if we assume that the direction parallel to and perpendicular to the rotation axis of the wave receiving rotor is the fore-and-aft direction of the float, when the float receives water surface waves and causes rolling (see Figure 5(c)), pitching (see Figures 5(a) and 5(b)), or heaving (see Figures 5(a) and 5(b)), the relative water flow generated in the water tends to act as an upward relative flow against the wave receiving surface of the wave receiving bucket in the first position, and it is presumed that the rotating main body and rotating axis are likely to rotate forward through the external force received by the wave receiving bucket in such first position.

[0031] On the other hand, when the submerged wave receiving bucket is in the second position, its wave receiving surface faces sideways when the float is floating on the water surface, and when a relative horizontal water flow acts toward this wave receiving surface, the wave receiving bucket in the second position is pushed relatively sideways, causing the rotating main body and rotating shaft to rotate in the forward direction.

[0032] Therefore, the wave receiving bucket in the submerged second position is suitable for converting relative water flows that act on the external force in a lateral direction, such as forward, backward, left, or right, rather than a relative water flow that acts on the external force by moving upward, into rotational motion of the rotation axis of the wave receiving rotor.

[0033] For example, if we assume that the direction parallel to and perpendicular to the rotation axis of the wave-receiving rotor is the fore-and-aft direction of the float, when the float is subjected to water surface waves and experiences motions such as surging or yawing, the relative water flow that occurs in the water is likely to act as a relative water flow that is transverse to the wave-receiving surface of the wave-receiving bucket in the second position, and it is estimated that the rotating main body and the rotation axis are likely to rotate forward through the external force received by the wave-receiving bucket in this second position.

[0034] The external forces received by the wave receiving surfaces of the wave receiving buckets in the first and second positions in this way are rotational forces that rotate the main rotating body in the forward direction because the wave receiving rotor is shaped like a waterwheel. This rotational force is generated when the wave receiving surfaces of each wave receiving bucket that has rotated to the first and second positions in turn are subjected to the external force of the relative water flow in the water. With this wave receiving rotor, not only the lateral movement of the relative water flow but also the upward movement of the relative water flow can be converted into driving force that rotates the wave receiving rotor.

[0035] In this way, the wave-receiving rotor can convert the movement of the relative water flow into rotational force, not only for the wave-receiving bucket in the second position, but also for the wave-receiving bucket in the first position, and this rotational force is used to rotate the rotating main body and rotating shaft, which in turn rotates the rotor part of the generator and generates electricity.This is different from conventional power generation systems that simply generate electricity by converting only the lateral movement of the relative water flow into rotational force.

[0036] Furthermore, when the rotating main body of the wave-receiving rotor begins to rotate in the forward direction, each wave-receiving bucket also begins to move circularly in the forward direction around the rotating axis together with the rotating main body, and one after another they come to the first and second positions, and are pushed by the movement of the relative water flow, moving from the first and second positions to further positions, and then they come back to the first and second positions again, repeating this action, maintaining the rotation of the rotating axis and continuing to rotate the rotor part of the generator, thereby continuing to generate electricity.

[0037] In particular, since the wave-receiving rotor can be rotated via the wave-receiving bucket in the first position, by keeping the float in a fixed position offshore, etc., it is possible to generate electricity using the rotational force of the wave-receiving rotor by taking advantage of the upward movement of the relative water current, even in places where there are no or weak backwash or surge waves, such as on or near the shore.

[0038] The wave power generation unit of the second invention is the wave power generation unit of the first invention, wherein the multiple wave-receiving buckets are arranged on the rotating main body at regular intervals on a pitch circle centered on the axis of the rotating shaft, and are equipped with a pointed tip portion that is pointed toward the forward rotation direction of the rotating main body, a wave-receiving surface that faces the opposite direction from the pointed tip portion and is concave toward the pointed tip portion, and a pointed outer peripheral surface whose outer diameter gradually decreases from the wave-receiving surface toward the pointed tip portion.

[0039] This wave power generation unit of the second invention achieves the same actions and effects as the wave power generation unit of the first invention, and in addition, each wave receiving bucket is formed so that its pointed tip and pointed outer surface face in the forward rotation direction of the rotating main body, thereby reducing the resistance coefficient when the wave receiving bucket moves relatively through the water as the rotating main body rotates, and by having at least a portion of the multiple wave receiving buckets submerged, the rotational resistance experienced by the wave receiving rotor can be reduced, and a decrease in the power generation efficiency of the generator operated by the rotation of the wave receiving rotor can be suppressed.

[0040] The wave power generation unit of the third invention is a wave power generation unit of the first or second invention, wherein the plurality of wave receiving buckets are arranged at regular intervals on a pitch circle centered on the axis of the rotating shaft, N number of wave receiving buckets, each of which is N-fold symmetrical with the pitch circle center as the axis of rotational symmetry, and when one wave receiving bucket is located at the first position, the other wave receiving buckets are located at the second position.

[0041] This wave power generation unit of the third invention not only achieves the same functions and effects as the wave power generation unit of the first or second invention, but also has the advantage that the wave receiving bucket is simultaneously positioned at the first and second positions underwater, and even if the rotating main body and rotating shaft rotate forward, the wave receiving buckets come to these first and second positions one after another simultaneously, so even if the relative water flow changes from moment to moment, the movement can be received by the wave receiving bucket at either the first or second position, and can be efficiently converted into rotational force for the rotating main body.

[0042] The wave power generation unit of the fourth invention is a wave power generation unit of any of the first to third inventions, wherein the wave receiving bucket is formed in a cone or frustum shape tapered such that the outer diameter gradually increases from the tip towards the wave receiving surface, and the wave receiving surface is a cone or frustum-shaped recess provided on the inner periphery of the wave receiving bucket.

[0043] This wave power generation unit of the fourth invention achieves the same actions and effects as any of the wave power generation units of the first to third inventions, and in addition, the shape of the wave receiving bucket is formed into a tapered cone or frustum shape with the outer diameter gradually increasing from the tip towards the wave receiving surface, so when the wave receiving rotor rotates forward, the resistance coefficient when the wave receiving bucket moves relatively through the water can be reduced, and since at least a portion of the multiple wave receiving buckets are submerged, the rotational resistance experienced by the wave receiving rotor can be reduced, and a decrease in the power generation efficiency of the generator operated by the rotation of the wave receiving rotor can be suppressed.

[0044] A wave power generation unit of a fifth invention is the wave power generation unit of any of the first to fourth inventions, wherein the wave receiving bucket comprises bucket bodies provided on the rotating main body part at regular intervals on a pitch circle centered on the axis of the rotating shaft, a tip end of the bucket body facing the normal rotation direction of the rotating main body part, a base end of the bucket body facing the reverse direction of the rotating main body part opposite to the tip end, a water passage which is a flow path provided penetrating the inside of the bucket body from the base end to the tip end of the bucket body, and an on-off valve formed to be freely movable between one of a closed position which closes the water passage and an open position which opens the water passage, and the other, and which controls a relative water flow which flows relatively from the base end side of the bucket body towards the tip end side thereof (hereinafter referred to as a "relative forward flow") The bucket has a wave-receiving surface that receives a water current (hereinafter referred to as a "relative backward flow") flowing relatively in the opposite direction to the relative forward flow at the closed position, and a wave-receiving member that moves from the closed position to the open position when it receives a relative water current (hereinafter referred to as a "relative backward flow") that flows relatively in the opposite direction to the relative forward flow. When the wave-receiving surface of the wave-receiving member receives the relative forward flow at the closed position, it converts the force accompanying the flow of the relatively forward flow into a rotational force for rotating the rotating main body in the forward direction, and when the wave-receiving member receives the relative backward flow at the closed position, it moves from the closed position to the open position and opens the water passage. The relative backward flow is allowed to pass through the inside of the bucket body through the opened water passage and escape, reducing the underwater resistance that the bucket body experiences.

[0045] The wave power generation unit of the sixth invention is the wave power generation unit of the fifth invention, further comprising a biasing member that biases the wave receiving member to move the wave receiving member back from the open position to the closed position, and when the wave receiving surface of the wave receiving member is subjected to a relative forward flow at the closed position, the wave receiving member converts the force associated with this relative forward flow into a rotational force for rotating the rotating main body in the forward direction, and when the wave receiving member is subjected to a force from a relative reverse flow at the closed position that exceeds the biasing force of the biasing member, the wave receiving member moves from the closed position to the open position, opening the water passage, and the relative reverse flow is allowed to pass through the inside of the bucket body through this opened water passage and escape, reducing the underwater resistance experienced by the bucket body.

[0046] The wave power generation unit of the fifth or sixth invention achieves the same functions and effects as any of the wave power generation units of the first to fourth inventions, and in addition, the wave receiving rotor is rotated forward by the relative forward flow caused by the multiple wave receiving buckets, while the relative reverse flow, which is opposite to the relative forward flow, reduces the underwater resistance that acts on the wave receiving buckets.

[0047] Specifically, when a relative downstream flow occurs with respect to the bucket body of the wave receiving bucket, the wave receiving member is moved to the blocking position by the force of the relative downstream flow in the case of the fifth invention, or by the force of the relative downstream flow and the biasing force of the biasing member in the case of the sixth invention, thereby blocking the water passage, and the wave receiving member in this blocking position is subjected to the relative downstream flow by its wave receiving surface, which pushes the wave receiving bucket in the forward rotation direction of the rotating main body, thereby generating a rotational force that rotates the rotating main body in the forward rotation direction. This rotational force in the forward rotation direction causes the wave receiving bucket to rotate in the forward direction.

[0048] On the other hand, if a relative backflow occurs against the bucket body of the wave receiving bucket, the force of the relative backflow in the case of the fifth invention, or the force of the relative backflow exceeding the biasing force of the biasing member in the case of the sixth invention, will push and move the wave receiving member from the closed position to the open position, opening the water passage as a result of this movement of the wave receiving member.The relative backflow will pass through this open water passage from the tip end to the base end of the bucket body and escape, reducing the underwater resistance that the bucket body experiences from this relative backflow.As a result, the relative backflow is prevented from pushing the wave receiving bucket back in the reverse direction, preventing interference with the forward rotation of the wave receiving rotor.

[0049] In the fifth aspect of the invention, when the force of the relative forward flow acts on the wave receiving member (wave receiving surface), the force of the relative forward flow, or in the sixth aspect of the invention, when the strength of the relative backward flow decreases and becomes weaker than the biasing force of the biasing member, the force of the relative forward flow, causes the wave receiving member to return from the open position to the closed position, and the water passage is blocked by the wave receiving member that has returned to this closed position. As a result, the wave receiving surface of the wave receiving member is returned to a state in which it is more susceptible to the relative forward flow.

[0050] The wave power generation unit of the seventh invention is a wave power generation unit of any of the first to sixth inventions, and is equipped with a mooring member that has one end attached to the float and the other end attached to the bottom of the water itself or a heavy object placed on the bottom of the water, mooring the float at a fixed location.

[0051] This wave power generation unit of the seventh invention has the same action and effect as any of the wave power generation units of the first to sixth inventions, and because the float is moored in a fixed location by mooring members, the float can be kept in an offshore location where water surface waves that cause the float to roll, pitch, heave, and other motions are likely to occur, making it possible to generate power using water surface waves even in places where there are no incoming or outgoing waves, such as on or near a shore.

[0052] The wave power generation unit of the eighth invention is a wave power generation unit of any of the first to seventh inventions, which has a rotor part that is a rotating body that is connected directly to the rotation shaft of the wave receiving rotor or connected to the rotation shaft of the wave receiving rotor via a connection transmission mechanism and is rotated by the rotational force of the rotation shaft, converts the rotation of the rotor part into electrical energy, and is equipped with a generator mounted on the floating body.

[0053] Here, the connecting transmission mechanism is a mechanism that is interposed between the rotating shaft of the wave receiving rotor and the rotor part of the generator, connects the rotating shaft of the wave receiving rotor and the rotor part of the generator, and transmits the rotation (force) of the rotating shaft of the wave receiving rotor to the rotor part of the generator.

[0054] A wave power generation unit of a ninth aspect of the present invention is the wave power generation unit of any one of the first to eighth aspects of the present invention, wherein the wave receiving rotors are provided on both sides of the float in the width direction in a plan view.

[0055] This wave power generation unit of the ninth invention has the same action and effect as any of the wave power generation units of the first to eighth inventions, and the wave receiving rotors located on both lateral sides of the float (the parts corresponding to the port and starboard sides if the float is considered to be a ship's hull) are rotated by receiving relative water currents in the water via wave receiving buckets located in the first and second positions, respectively.

[0056] A wave power generation unit according to a tenth aspect of the present invention is the wave power generation unit according to any one of the first to ninth aspects of the present invention, wherein the wave receiving rotors are provided on both sides of the floating body in the longitudinal direction in a plan view.

[0057] This wave power generation unit of the 10th invention has the same action and effect as any of the wave power generation units of the 1st to 9th inventions, and the wave receiving rotors located on both sides of the float in the fore-and-aft direction (the parts corresponding to the bow and stern if the float is considered to be a ship's hull) are rotated by receiving relative water currents in the water via wave receiving buckets located in the first and second positions, respectively.

[0058] The wave power generation system of the 11th invention comprises a wave power generation unit of any one of the first to tenth inventions, a power transmission means for transmitting the power generated by the wave power generation unit, and power equipment for receiving the power transmitted by the power transmission means. [Effects of the Invention]

[0059] According to the wave power generation unit and wave power generation system of the present invention, the wave receiving rotor mounted on the floating body not only converts the lateral relative water current movement into rotational force via the wave receiving bucket in the second position, but also converts the upward relative water current movement into rotational force via the wave receiving bucket in the first position. This allows the rotor of the generator to be rotated to generate electricity by comprehensively utilizing the rotational forces of these different relative water currents. This distinguishes the system from conventional power generation systems that simply use the horizontal flow of incoming and outgoing waves on coastal areas to generate electricity. This system has the advantageous effect of being able to generate electricity using water surface waves with up-and-down motion that occur on the water surface offshore. This avoids the impact of breaking waves and reduces damage to the wave power generation unit caused by such impact. [Brief explanation of the drawings]

[0060] [Figure 1] (a) is a right side view of a wave power generation unit used in a wave power generation system that is one embodiment of the present invention, and is a projection view of the port front, and (b) is a longitudinal cross-sectional view along line IB-IB of (a), which is a longitudinal cross-sectional view of the bow of the wave power generation unit. [Figure 2] (a) is a plan view of the wave power generation unit, and (b) is a configuration diagram showing the main equipment installed inside the floating body. [Figure 3] (a) is a side view of the wave receiving rotor installed on the port side of the floating body, and is an explanatory diagram of the first to fourth positions of the wave receiving bucket submerged in water on the wave receiving rotor, and (b) is an enlarged oblique view of the wave receiving bucket. [Figure 4] FIG. 1 is a diagram showing the mooring state of a wave power generation unit. [Figure 5] An explanatory diagram illustrating the state in which a wave power generation unit is subjected to a relative water flow, where (a) is a right side view of the wave power generation unit, (b) is a left side view of the wave power generation unit, and (c) is a front view of the wave power generation unit. [Figure 6] FIG. 10 is a side view of the wave receiving rotor of the wave power generation unit of the second embodiment, illustrating first to fourth positions of the wave receiving bucket of the wave receiving rotor submerged in water. [Figure 7] 10A and 10B are explanatory diagrams illustrating the operating state of each wave receiving bucket used in the wave receiving rotor of the wave power generation unit of the second embodiment, where (a) is an oblique view showing the state in which the wave receiving member of the wave receiving bucket blocks the tip opening, (b) is a longitudinal cross-sectional view showing the internal structure of the wave receiving bucket of (a), (c) is an oblique view showing the state in which the wave receiving member of the wave receiving bucket opens the tip opening, and (d) is a longitudinal cross-sectional view showing the internal structure of the wave receiving bucket of (c). DETAILED DESCRIPTION OF THE INVENTION

[0061] An embodiment of the present invention will be described below with reference to the accompanying drawings. For convenience, in this embodiment, the terms bow, stern, port side, and starboard side will be used for the wave power generation unit 1 and its floating body 2, just as in the case of a ship hull. Specifically, the left side of Fig. 1(a) and the left side of Fig. 2(a) will be defined as the bow section 21, the right side of Fig. 1(a) and the right side of Fig. 2(a) will be defined as the stern section 22, the front side of Fig. 1(a) and the lower side of Fig. 2(a) will be defined as the port side 23, and the back side of Fig. 1(a) and the upper side of Fig. 2(a) will be defined as the starboard side 24.

[0062] Fig. 1(a) is a right side view and a port front projection of a wave power generation unit 1 used in a wave power generation system that is one embodiment of the present invention, and Fig. 1(b) is a longitudinal cross-sectional view along line IB-IB in Fig. 1(a), showing a longitudinal cross-sectional view of the bow 21 of the wave power generation unit 1. Note that Fig. 1 illustrates a state in which a floating body 2 is floating on a horizontal water surface 100, and the left side view and starboard front projection of the wave power generation unit 1 appears in a form that is bilaterally symmetrical to the diagram in Fig. 1(a). Note that Figs. 1 to 5 show the coordinate axes XYZ of a spatially fixed coordinate system.

[0063] Fig. 2(a) is a plan view of the wave power generation unit 1, and Fig. 2(b) is a configuration diagram showing the main devices installed inside the floating body 2. Note that Fig. 2 illustrates a state in which the floating body 2 is floating on a horizontal water surface 100.

[0064] Figure 3(a) is a side view of the wave receiving rotor 3 provided on the port side 23 of the floating body 2, and is an explanatory diagram of the first position P1 to the fourth position P4 of the wave receiving bucket 32 ​​submerged in water 102 on the wave receiving rotor 3, and Figure 3(b) is an enlarged oblique view of the wave receiving bucket 32.

[0065] Here, Figure 3(a) shows the state in which the float 2 is floating on a horizontal water surface 100 and the wave receiving rotor 3 is stopped, and the float 2 is omitted from the illustration, and all the wave receiving buckets 32 are viewed in vertical cross section, with the first position P1 to the fourth position P4 indicated by dashed double-dashed lines and the forward rotation direction of the wave receiving rotor 3 indicated by a solid arrow, and Figure 3(b) shows only one wave receiving bucket 32, and in Figure 3 the flow of the relative water flow 103 is indicated by a hollow arrow.

[0066] Here, the relative water flow 103 refers to the relative water flow that occurs in the water 102 based on the relative movement between the swaying movement of the water surface wave 101 and the floating body 2 that sways in response to this water surface wave 101. In particular, in Figures 3(a) and 5, the upward relative water flow 103 received by the wave receiving surface 32b of the wave receiving bucket 32P1 is denoted by the symbol "103a", the lateral relative water flow 103 received by the wave receiving surface 32b of the wave receiving bucket 32P2 is denoted by the symbol "103b", the downward relative water flow 103 received by the wave receiving surface 32b of the wave receiving bucket 32P3 is denoted by the symbol "103c", and the lateral relative water flow 103 received by the wave receiving surface 32b of the wave receiving bucket 32P4 (relative water flow in the opposite direction to the relative water flow 103b) is denoted by the symbol "103d".

[0067] Figure 4 is a longitudinal cross-sectional view of the water 102 in offshore waters, showing the moored state of the wave power generation unit 1. Note that Fig. 4 omits the mooring members 6 and part of the transmission line 7. Note that Fig. 4 illustrates a state in which the floating body 2 is floating on a horizontal water surface 100.

[0068] Figure 5 is an explanatory diagram showing a longitudinal cross section of the water 102 in offshore waters, illustrating the state in which the wave power generation unit 1 floats on the water surface 100 in response to a relative water current 103, where Figure 5(a) is a right side view of the wave power generation unit 1 (projection of the port front), Figure 5(b) is a left side view of the wave power generation unit 1 (projection of the starboard front), and Figure 5(c) is a front view of the wave power generation unit 1 (projection of the bow front).

[0069] 5, the small white arrows indicate the direction of the relative water flow 103, the large white arrows indicate the movement of the water surface waves 101, and the solid arrows indicate the direction of rotation of the wave receiving rotor 3. In addition, in FIG. 5, the wave receiving bracket 32 ​​in the first position is denoted by the symbol "32P1," the wave receiving bracket 32 ​​in the second position is denoted by the symbol "32P2," the wave receiving bracket 32 ​​in the third position is denoted by the symbol "32P3," and the wave receiving bracket 32 ​​in the fourth position is denoted by the symbol "32P4."

[0070] As shown in Figures 1 to 5, the wave power generation unit 1 is installed floating on a water surface 100 such as an ocean or lake where water surface waves 101 are generated offshore, and generates electricity using the water surface waves 101 generated on the water surface 100.

[0071] This wave power generation unit 1 mainly comprises a float 2, a wave receiving rotor 3, a connecting transmission mechanism 4, a generator 5, and a mooring member 6, and a wave power generation system using this wave power generation unit 1 also comprises, in addition to this wave power generation unit 1, a transmission line 7 and onshore power equipment (not shown).

[0072] As shown in Figure 1, the floating body 2 is installed on a water surface 100 such as the surface of the sea or a lake, and is configured to be able to float on the water surface 100 through its buoyancy, and to sway in response to water surface waves 101 generated on the water surface 100 (see Figure 5).

[0073] In response to the swaying motion of water surface waves 101, this floating body 2 oscillates in a manner that combines one or more of the following movements: movement in the X-axis direction (including both positive and negative coordinate axis directions; the same applies below), which is the coordinate axis of a spatially fixed coordinate system fixed to the ground surface; movement in the Y-axis direction; movement in the Z-axis direction; rotation around the X-axis (including both positive and negative rotation directions; the same applies below); rotation around the Y-axis; or rotation around the Z-axis direction.

[0074] The float 2 is formed in the shape of a ship hull, and a storage space 25 is provided inside the float 2. The storage space 25 is a space for storing the generator 5 and the connecting transmission mechanism 4, and the float 2 itself serves as a storage casing 26 that covers the entire storage space 25. The storage casing 26 is a casing that covers the storage space 25 in a sealed state, and prevents water such as seawater or lake water from entering the storage space 25 from the outside, preventing the generator 5 and the connecting transmission mechanism 4 from being submerged.

[0075] As shown in Figure 2(a), the floating body 2 has a bow section 21 which is its front part, a stern section 22 which is its rear part, a starboard section 24 which is its right part, and a port section 23 which is its left part. The floating body 2 is provided with a wave receiving rotor 3 at the port section 23 (lower left side of Figure 2(a)) and starboard section 24 (upper left side of Figure 2(a)) on the bow section 21 side, and at the port section 23 (lower right side of Figure 2(a)) and starboard section 24 (upper right side of Figure 2(a)) on the stern section 22 side, so that the floating body 2 as a whole is provided with a total of four wave receiving rotors 3 on the front, rear, left and right sides.

[0076] These four wave receiving rotors 3, located front to back, left to right, are driven to rotate by relative water currents 103 (see Figure 5) in the water 102. Each wave receiving rotor 3 is shaped like a water wheel, is formed in the same shape, and is configured to rotate in the same forward direction. All wave receiving rotors 3 are driven to rotate by relative water currents 103 generated in the water 102, and each comprises a rotating main body 31, multiple wave receiving buckets 32, and a rotating shaft 33.

[0077] As shown in Fig. 1, the rotating main body 31 of the wave receiving rotor 3 is a ring-shaped body that is the main body of the wave receiving rotor 3, and is formed in a roughly circular shape in side view. This rotating main body 31 has a boss 31a at its center, and a rotating shaft 33 is fixed to this boss 31a. This rotating shaft 33 is the rotating shaft 33 of the wave receiving rotor 3 and its rotating main body 31, and is formed integrally with the rotating main body 31. In addition, the rotating shaft 33 is rotatably supported by the floating body 2 via a bearing 26 (see Fig. 2(b)) provided on the floating body 2 (see Fig. 1(b)).

[0078] As shown in Figure 2(b), the rotating shaft 33 of the receiving rotor 3 is an axial body whose axis coincides with the center of rotation of the rotating main body 31, and the rotating main body 31 is connected to its base end, while the connecting transmission mechanism 4 is connected to its tip end.

[0079] The connecting transmission mechanism 4 is a mechanism that is interposed between the rotating shaft 33 of the wave receiving rotor 3 and the rotor part 51 of the generator 5, connects the rotating shaft 33 of the wave receiving rotor 3 and the rotor part 51 of the generator 5, and transmits the rotation (force) of the rotating shaft 33 of the wave receiving rotor 3 to the rotor part 51 of the generator 5, and is mainly equipped with a speed increaser 41 and a flywheel 42.

[0080] The speed increaser 41 includes a low-speed input shaft 41a that is rotated by receiving external rotational force, a plurality of gears (not shown) that increase the speed of the rotation input from the low-speed input shaft 41a and output it, and a high-speed output shaft 41b that rotates at the increased rotational speed output from the plurality of gears. According to the speed increaser 41, the rotating shaft 33 of the wave receiving rotor 3 is concentrically connected to the low-speed input shaft 41a, and the rotor part 51 of the generator 5 is concentrically connected to the high-speed output shaft 41b via a flywheel 42. Therefore, the rotor part 51 and flywheel 42 of the generator 5 rotate at a higher speed than the wave receiving rotor 3 and its rotating shaft 33.

[0081] The flywheel 42 is what is called a flywheel, and when the rotational force obtained by the rotation of the wave receiving rotor 3 is transmitted to the flywheel 42 via the speed increaser 41, the flywheel 42 rotates and stores the rotational inertia energy. The flywheel 42 is housed in a casing 42a and is supported by a low-friction bearing 42b, so that the rotational inertia energy obtained by the rotation of the wave receiving rotor 3 can be stored with low loss.

[0082] In this way, the flywheel 42 can store the rotational inertia energy obtained by the rotation of the wave-receiving rotor 3. Therefore, even in a situation where, for example, the water surface waves 101 temporarily weaken and the rotation of the wave-receiving rotor 3 stops or slows down, the rotational inertia energy stored in the flywheel 42 can be used to rotate the rotor part 51 of the generator 5, thereby continuing power generation.

[0083] The generator 5 comprises a stator section (not shown) that is fixed to a casing 52 and generates a magnetic field, and a rotor section 51 that is rotatably provided within the stator section and is a rotating body that rotates within the magnetic field of the stator section. The generator 5 is a device that converts the rotation of the rotor section 51 into electrical energy, and generates electricity by generating electromotive force through electromagnetic induction as the rotor section 51 rotates within the magnetic field generated by the stator section.

[0084] In addition, the generator 5 has a main shaft 51a of its rotor section 51 and one end (left side of FIG. 3(b)) of the center shaft 42a of the flywheel 42 connected and fixed on the same axis, and the other end (right side of FIG. 3(b)) of the center shaft 42a of the flywheel 42 connected and fixed on the same axis with the high-speed output shaft 41b of the speed increaser 41. Therefore, the rotation of the wave receiving rotor 3 rotates the flywheel 42 via the speed increaser 41, and also rotates the rotor section 51 of the generator 5.

[0085] Each generator 5 of the wave power generation unit 1 converts the kinetic energy generated by the rotation of the multiple wave-receiving rotors 3 into electricity, and the generated electricity is sent to a power facility (not shown) on land via a transmission line 7 connected to each generator 5.

[0086] As shown in Figure 3(a), the wave receiving rotor 3 comprises a rotating main body 31, a rotating shaft 33, a plurality of wave receiving buckets 32, and a wave receiving surface 32b formed on each of the wave receiving buckets 32. Note that each of the plurality of wave receiving rotors 3 provided on the floating body 2 has the same shape, and all are formed in the shape of a water wheel as a whole, so only one wave receiving rotor 3 will be described in Figure 3.

[0087] According to this wave receiving rotor 3, the rotating main body 31 is a member that supports multiple wave receiving buckets 32 in predetermined positions, and all of the multiple wave receiving buckets 32 are formed in the same shape. When the float 2 is floating on a horizontal water surface 100, this wave receiving rotor 3 is a member that generates the rotational force required to rotate the rotor part 51 of the generator 5 by having all of the multiple wave receiving buckets 32 submerged in water 102 and directly receiving a relative water current 103.

[0088] The wave receiving rotor 3 has a plurality of wave receiving buckets 32 provided at predetermined intervals around the entire outer periphery of its rotating main body 31. Eight wave receiving buckets 32 are provided at regular intervals on a pitch circle P centered on the axis of the rotating shaft 33 of the rotating main body 31, and each wave receiving bucket 32 ​​is eight-fold symmetrical with the center of the pitch circle P as the axis of rotational symmetry, and are provided at equal intervals around the entire outer periphery of the rotating main body 31.

[0089] Each wave receiving bucket 32 ​​has a pointed tip 32a that is pointed in the forward rotation direction of the rotating body 31 (the direction of the arrow in Figure 3(a)). Each wave receiving bucket 32 ​​also has a wave receiving surface 32b formed on the end surface facing in the reverse direction (the direction opposite to the arrow in Figure 3(a)) from the tip 32a, and this wave receiving surface 32b is shaped to be concave toward the tip 32a. Each wave receiving bucket 32 ​​also has a pointed outer peripheral surface 32c whose outer diameter gradually decreases from the wave receiving surface 32b toward the tip 32a.

[0090] 3(b), the wave receiving bucket 32 ​​has a conical shape with its outer diameter gradually increasing from its tip 32a to its wave receiving surface 32b, and its pointed outer peripheral surface 32c is tapered. The wave receiving surface 32b of the wave receiving bucket 32 ​​is a conical recess provided on the inner periphery of the conical wave receiving bucket 32.

[0091] Here, the tip 32a and pointed outer surface 32c of the wave receiving bucket 32 ​​have an overall conical shape, so that when the wave receiving bucket 32 ​​rotates in the forward direction (the direction of the solid arrow in Figure 5), the resistance it receives from the water in the water 102 can be reduced.

[0092] As shown in Figure 3(a), the wave receiving rotor 3 is in a state where all of the multiple wave receiving buckets 32 are submerged in water 102 when the float 2 is floating on the water surface 100, and of the submerged wave receiving buckets 32, four wave receiving buckets 32 are located at a first position P1 where their wave receiving surfaces 32b face downward, a second position P2 where their wave receiving surfaces 32b face sideways (facing rearward of the float 2), a third position P3 where their wave receiving surfaces 32b face upward, and a fourth position P4 where their wave receiving surfaces 32b face sideways (facing forward of the float 2).

[0093] Here, with this wave power generation unit 1, even when subjected to the swaying motion of the water surface waves 101 and the rocking motion of the float 2, all or most of the multiple wave receiving rotors 3 remain submerged in the water 102, and in particular, the wave receiving buckets 32P1, 32P2, 32P3 located at the first position P1, the third position P3 and the second position P2 are always maintained submerged in the water 102 regardless of the water surface waves 101 and the rocking motion of the float 2.

[0094] Of the multiple wave receiving buckets 32 submerged in the water 102, at least the wave receiving bucket 32 ​​at the first position P1 has its downward wave receiving surface 32b, the wave receiving bucket 32 ​​at the second position P2, which is rotated approximately 90° in the reverse direction from the first position P1 around the axis of the rotation shaft 33, has its sideways (towards the rear of the float 2) wave receiving surface 32b, the wave receiving bucket 32 ​​at the third position P3, which is rotated approximately 90° in the reverse direction from the second position P2 around the axis of the rotation shaft 33, has its downward wave receiving surface 32b, and the wave receiving bucket 32 ​​at the fourth position P4, which is rotated approximately 90° in the reverse direction from the third position P3 around the axis of the rotation shaft 33, has its sideways (towards the front of the float 2) wave receiving surface 32b, each of which receives the relative water flow 103 generated in the water 102 and applies a rotational force to the rotating main body part 31.

[0095] In other words, the wave receiving rotor 3 is arranged so that the wave receiving surface 32b of the wave receiving bucket 32P1 at the first position P1 receives the relative water flow 103a, the wave receiving surface 32b of the wave receiving bucket 32P2 at the second position P2 receives the relative water flow 103b, the wave receiving surface 32b of the wave receiving bucket 32P3 at the third position P3 receives the relative water flow 103c, and the wave receiving surface 32b of the wave receiving bucket 32P4 at the fourth position P4 receives the relative water flow 103d.

[0096] Therefore, with the multiple wave receiving buckets 32, the wave receiving surface 32b of the wave receiving bucket 32P1 at the first position P1 faces downward and is pushed by the upward relative water flow 103a, the wave receiving surface 32b of the wave receiving bucket 32P2 at the second position P2 faces sideways (towards the rear of the float 2 (right side in Figure 3(a))) and is pushed by the sideways relative water flow 103b (water flow coming relatively from the rear of the float 2), and the wave receiving surface 32b of the wave receiving bucket 32P3 at the third position P3 faces upward and is pushed by the downward relative water flow 103c. The wave receiving surface 32b of the wave receiving bucket 32P4 at the fourth position P4 is pushed and moved sideways (facing forward of the float 2 (left side of Figure 3(a)), i.e., facing the opposite direction to the wave receiving surface 32b of the wave receiving bucket 32P2 at the second position P2) and is pushed and moved by the relative water flow 103d that is sideways (water flow coming relatively from the front of the float 2, i.e., opposite to the sideways relative water flow 103b received by the wave receiving surface 32b of the wave receiving bucket 32P2 at the second position P2), causing the wave receiving rotor 3 to rotate in the forward direction.

[0097] However, the relative water flow 103 inside the water 102 is not necessarily limited to vertical and horizontal water flow like the relative water flows 103a to 103d, and movement of the relative water flow 103 can occur in directions other than these depending on the situation at the time. As a result, of the multiple wave receiving buckets 32 that are submerged, not only the wave receiving buckets 32 located at the first position P1 to the fourth position P4 receive the movement of the relative water flow 103 on their wave receiving surfaces 32b and impart a rotational force to the wave receiving rotor 3, but even at positions other than the first position P1 to the fourth position P4, the wave receiving buckets 32 receive the relative water flow 103 on their wave receiving surfaces 32b and impart a rotational force to the wave receiving rotor 3.

[0098] In other words, it is naturally possible that the wave receiving bucket 32 ​​submerged at a position different from the first position P1 to the fourth position P4 will receive a relative water flow 103 heading toward its wave receiving surface 32b, generating a rotational force that rotates the wave receiving rotor 3 in the forward direction. It is clear that the same applies to the second embodiment described below.

[0099] As shown in Figure 4, the mooring member 6 is a string-like or rope-like member such as a wire or chain for mooring the floating body 2 at a fixed location. One end of the mooring member 6 is fastened to the floating body 2, and the other end is fastened to a heavy object 8 installed on the water bottom 104. The heavy object 8 is, for example, a sinker, an anchor, or another heavy object. The other end (lower end) of the mooring member 6 may be fixed by driving it into the water bottom 104 itself.

[0100] As shown in Figure 5, with the wave power generation unit 1, the floating body 2 floats in offshore waters due to buoyancy. In offshore waters, fluid particles in the water 102 in a longitudinal cross section of the waters undergo circular motion or a similar elliptical motion (an elliptical motion with a vertical minor axis and a horizontal major axis) when viewed from the side, and the motion of water surface waves 101 is such that the water surface 100 where the floating body 2 is present and the water 102 near the water surface 100 reciprocate horizontally as well as up and down (vertical) directions.

[0101] As the water surface waves 101 sway horizontally and vertically in this manner, the floating body 2 of the wave power generation unit 1 also sways on the water surface 100, and a relative water flow 103 is generated in the floating body 2 and each wave receiving rotor 3 based on the swaying of the floating body 2 and the movement of the water surface waves 101.

[0102] All of the wave receiving rotors 3 have all of their wave receiving buckets 32 submerged in water 102, and the wave receiving surfaces 32b of the wave receiving buckets 32P1, 32P2, 32P3, and 32P4 located at the first position P1 to the fourth position P4 are rotated in the forward direction by receiving the corresponding relative water flows 103a, 103b, 103c, and 103d, respectively.

[0103] Specifically, when the float 2 is floating on the water surface 100, the wave receiving bucket 32P1 at the first position P1 has its wave receiving surface 32b facing downward, and when an upward relative water flow 103a acts on this wave receiving surface 32b, the wave receiving bucket 32P1 at the first position P1 is pushed relatively upward, causing the rotating main body 31 and the rotating shaft 33 to rotate in the forward direction (the direction of the solid arrow in Figure 5).

[0104] Therefore, the wave receiving bucket 32P1 at the submerged first position P1 converts the relative water flow 103a, which acts as an external force in an upward direction, into rotational motion of the rotation axis 33 of the wave receiving rotor 3, rather than the relative water flows 103b and 103d, which act as external forces in lateral directions such as forward, backward, left and right.

[0105] Furthermore, when the submerged wave receiving bucket 32P3 is at the third position P3, its wave receiving surface 32b faces upward when the float 2 is floating on the water surface 100, and when a downward relative water flow 103c acts on this wave receiving surface 32b, the wave receiving bucket 32P3 at the third position P3 is pushed relatively downward, causing the rotating main body 31 and the rotating shaft 33 to rotate in the forward direction (the direction of the solid arrow in Figure 5).

[0106] Therefore, the wave receiving bucket 32P3 at the submerged third position P3 converts the relative water flow 103c, which acts as an external force in a downward direction, into rotational motion of the rotation axis 33 of the wave receiving rotor 3, rather than the relative water flows 103b and 103d, which act as external forces in lateral directions such as forward, backward, left and right.

[0107] For example, when the floating body 2 receives water surface waves 101 and experiences motions such as rolling (see Figure 5(c)), pitching (see Figures 5(a) and 5(b)), or heaving (see Figures 5(a) and 5(b)), the relative water flow 103 generated in the water 102 acts as an upward relative water flow 103a on the wave receiving surface 32b of the wave receiving bucket 32P1 at the first position P1, and as a downward relative water flow 103c on the wave receiving surface 32b of the wave receiving bucket 32P3 at the third position P3, and the rotating body 31 and the rotating shaft 33 are rotated forward through the external forces received by the wave receiving buckets 32P1, 32P3 at the first position P1 and the third position P3.

[0108] On the other hand, when the submerged wave receiving bucket 32P2 is at the second position P2, its wave receiving surface 32b is turned sideways when the float 2 is floating on the water surface 100, and when a relative horizontal water flow 103b acts on this wave receiving surface 32b, the wave receiving bucket 32P2 at the second position P2 is pushed relatively sideways, causing the rotating main body 31 and the rotating shaft 33 to rotate in the forward direction.

[0109] Therefore, the wave receiving bucket 32P2 at the submerged second position P2 converts the relative water flows 103b, 103d, which act as external forces in lateral directions such as forward, backward, left and right, into rotational motion of the rotation axis 33 of the wave receiving rotor 3, rather than the relative water flows 103a, 103c, which move upward and act as external forces.

[0110] Furthermore, when the submerged wave receiving bucket 32P4 is at the fourth position P4, its wave receiving surface 32b is turned sideways when the float 2 is floating on the water surface 100, and when a relative horizontal water flow 103d acts on this wave receiving surface 32b, the wave receiving bucket 32P4 at the fourth position P4 is pushed relatively sideways, causing the rotating main body 31 and the rotating shaft 33 to rotate in the forward direction.

[0111] Therefore, the wave receiving bucket 32P4 at the submerged fourth position P4 converts the relative water flows 103b, 103d, which act as external forces in lateral directions such as front, back, left and right, rather than the relative water flows 103a, 103c, which move upward and act as external forces, into rotational motion of the rotation axis 33 of the wave receiving rotor 3.

[0112] For example, if we assume that the direction parallel to and perpendicular to the rotation axis 33 of the wave receiving rotor 3 is the fore-and-aft direction of the float 2, when the float 2 receives water surface waves 101 and experiences motions such as surging or yawing, the relative water flow 103 generated in the water 102 acts as a lateral relative water flow 103b on the wave receiving surface 32b of the wave receiving bucket 32P2 at the second position P2, and also acts as a lateral relative water flow 103d on the wave receiving surface 32b of the wave receiving bucket 32P4 at the fourth position P4, and the rotating main body 31 and the rotation axis 33 are rotated forward through the external forces received by the wave receiving buckets 32P2, 32P4 at the second position P2 and the fourth position P4.

[0113] In other words, with this wave receiving rotor 3, not only the movement of the lateral relative water currents 103b, 103d but also the movement of the upward and downward relative water currents 103a, 103c can be converted into a driving force that rotates the wave receiving rotor 3.

[0114] In this way, according to the wave power generation unit 1, each of the wave receiving rotors 3 receives external forces from the relative water flows 103a to 103d and other relative water flows 103 associated with the wave receiving buckets 32P1 to 32P4 and each of the wave receiving surfaces 32b of the other wave receiving buckets 32P1 to 32P4, and is rotated in the forward direction.This rotation rotates the rotor part 51 of the generator 5 via the connecting transmission mechanism 4, generating electricity, and the generated electricity is transmitted to the power equipment via the transmission line 7.

[0115] Fig. 6 is a side view of the wave receiving rotor 130 of the wave power generation unit of the second embodiment, and is an explanatory diagram of the first position P1 to the fourth position P4 of the wave receiving buckets 131 submerged in the water 102 of the wave receiving rotor 130. For convenience, Fig. 6 illustrates a state in which the wave receiving members 133 of all the wave receiving buckets 131 are in the closed position.

[0116] Figure 7 is an explanatory diagram explaining the operation of the wave receiving bucket 131 used in the wave receiving rotor 130 of the wave power generation unit of the second embodiment, Figure 7(a) is an oblique view showing the state in which the wave receiving member 133 of the wave receiving bucket 131 blocks the tip opening 132c1, Figure 7(b) is a vertical cross-sectional view showing the internal structure of the wave receiving bucket 131 of Figure 7(a), Figure 7(c) is an oblique view showing the state in which the wave receiving member 133 of the wave receiving bucket 131 opens the tip opening 132c1, and Figure 7(d) is a vertical cross-sectional view showing the internal structure of the wave receiving bucket 131 of Figure 7(c).

[0117] Here, Figure 6 shows the state in which the float is floating on a horizontal water surface and the wave receiving rotor 130 is stopped, the float is not shown, and all the wave receiving buckets 131 are viewed in vertical cross section, with the first position P1 to the fourth position P4 indicated by dashed double-dashed lines and the forward rotation direction of the wave receiving rotor 130 indicated by a solid arrow, and Figure 7 shows only one wave receiving bucket 131.

[0118] 6 and 7, the flow of the relative water flow 103 is shown by open arrows, and the relative water flow 103 shown by the open arrows in FIGS. 6, 7(a), and 7(b) indicates a "relative forward flow 103A," which is a relative water flow 103 flowing from the base end side of the bucket body 132 to its tip end side, and the relative water flow 103 shown by the open arrows in FIGS. 7(c) and 7(d) indicates a "relative reverse flow 103B," which is a relative water flow 103 flowing in the opposite direction to the relative forward flow 103A, i.e., from the base end side of the bucket body 132 to its tip end side.

[0119] Furthermore, the base end of the bucket body 132 refers to the portion where the base end face 132a and the base end opening 132a1 are located, and the tip end of the bucket body 132 refers to the portion of the bucket body 132 where the tip end face 132c, tip end opening 132c1, and tip end bulkhead 132d, which will be described later, are located. Note that the "base end" of the bucket body 132 is also the "base end" of the wave receiving bucket 131, and the "tip end" of the bucket body 132 is also the "tip end" of the wave receiving bucket 131.

[0120] Furthermore, the state (shape) of the wave receiving member 133 shown in Figure 6 indicates a state in which this wave receiving member 133 exists (is located) in a closed position, and the state (shape) of the wave receiving member 133 shown in Figures 7(a) and 7(b) indicates a state in which this wave receiving member 133 exists (is located) in an open position.

[0121] The wave power generation unit of the second embodiment is different from the wave power generation unit 1 of the first embodiment in that the shape of the wave receiving bucket 131 of the wave receiving rotor 130 is changed. In this second embodiment, the wave receiving rotor 130 and its wave receiving bucket 131 are described, and the same parts as in the first embodiment are given the same reference numerals and their description is omitted, while different parts are given different reference numerals and their description is omitted. In the second embodiment, even for parts given different reference numerals from the first embodiment, description of the same content as in the first embodiment is omitted.

[0122] As shown in Fig. 6, the wave receiving rotor 130 used in the wave power generation unit of the second embodiment has a plurality of wave receiving buckets 131, each having a different shape from the wave receiving bucket 131 of the first embodiment, mounted on the rotating main body 31. Note that Fig. 6 shows only one wave receiving rotor 130, but two or more such wave receiving rotors 130 may be mounted on the floating body (not shown) of this wave power generation unit.

[0123] The wave receiving rotor 130 of the second embodiment is provided with a plurality of wave receiving buckets 131 and has an overall waterwheel-like shape. All of the wave receiving buckets 131 of this wave receiving rotor 130 are formed in the same shape. Here, eight wave receiving buckets 131 are provided at regular intervals on a pitch circle P around the entire outer periphery of the rotating main body 31 of the wave receiving rotor 130, and are provided at equal intervals all around the outer periphery of the rotating main body 31 in eight-fold symmetry with the center of the pitch circle P as the axis of rotational symmetry.

[0124] The wave-receiving bucket 131 has a bucket body 132 formed as a hollow cylindrical rectangular parallelepiped with a space provided on its inner periphery. The bucket body 132 has a wave-receiving member 133 with a wave-receiving surface 133a that receives the relative water flow 103 (assumed forward flow 103A). The bucket body 132 is fixed to the rotating body 31 so that its tip faces the forward rotation direction of the rotating body 31 (the direction of the solid arrow in Figure 6) and its base faces the reverse rotation direction of the rotating body 31 (the direction opposite to the solid arrow in Figure 6).

[0125] The outer shape of the bucket body 132 is not limited to a hollow cylindrical rectangular parallelepiped, but may be, for example, a polygonal prism, a cylinder, or any other shape as long as it is hollow cylindrical.

[0126] 7(a) and 7(b), the bucket body 132 has a base end opening 132a1, which is a rectangular opening in a front view, formed on its base end surface 132a. Behind this base end opening 132a1, a water-receiving space 132b is formed, which is a space provided on the inner periphery of the bucket body 132 and receives the relative water flow 103 (relatively forward flow 103A). This water-receiving space 132b is in communication with the base end opening 132a1, so that the relative water flow 103 (relatively forward flow 103A) can flow into the water-receiving space 132b from the base end opening 132a1.

[0127] A wave receiving member 133 is provided at the innermost part of the water receiving space 132b. This wave receiving member 133 is a plate-shaped on-off valve for receiving the relative water flow 103 (relative forward flow 103A) flowing into the water receiving space 132b from the base end opening 132a1, and the surface of this wave receiving member 133 facing the base end opening 132a1 side (the reversing direction of the rotating main body 31 (the direction opposite to the solid arrow in Figure 6)) forms the wave receiving surface 133a. The wave receiving surface 133a blocks the relative water flow 103 (relative forward flow 103A) within the water receiving space 132b, and the force of the relative water flow 103 (relative forward flow 103A) flowing into the water receiving space 132b acts on the wave receiving bucket 131 as an external force, causing the wave receiving rotor 130 to rotate forward.

[0128] As shown in Figures 7(b) and 7(c), the bucket body 132 has a tip opening 132c1, which is a rectangular opening in front view, formed in the tip surface 132c. This tip opening 132c1 is formed in the center of tip partition 132d, which is a partition at the tip of the bucket body 132, and communicates with the innermost part of the water-receiving space 132b of the bucket body 132 (see Figures 7(c) and 7(d)). In addition, the tip opening 132c1 is closed by a wave-receiving member 133 (see Figure 7(b)).

[0129] In this way, the wave receiving member 133 has the wave receiving surface 133a as described above and functions to receive the relative water flow 103 (relative forward flow 103A), while also functioning as an opening / closing valve that opens and closes the tip opening 132c1.

[0130] As shown in Figure 7(b), the wave receiving member 133 has its wave receiving surface 133a, and the back side (hereinafter referred to as the "opening operating surface") 133b abutting against the inner surface of the tip partition 132d of the bucket body 132, and is formed so that in this abutting state (blocking position), the tip opening 132c1 is blocked, and the abutment between this opening operating surface 133b and the tip partition 132d stops the wave receiving member 133 in the blocking position, preventing it from rotating further in the blocking direction.

[0131] The wave receiving member 133 is pivotally supported on the bucket body 132 via a swing shaft 133c in a state in which it can swing freely within the water receiving space 132b. The wave receiving member 133 is elastically biased around the swing shaft 133c toward the tip partition wall 132d by a biasing member (not shown) such as an elastic spring. The solid arrow in Figure 7 indicates the biasing direction of the biasing member.

[0132] The back side of the wave receiving surface 133a of the wave receiving member 133 is the opening operating surface 133b, and when an external force that exceeds the biasing force of the biasing member acts on this opening operating surface 133b, it is swung in the counter-bias direction (the opposite direction of the solid arrow in Figure 7) around the swing axis 133c, and moves from a state in which the tip opening 132c1 is blocked in the closed position as shown in Figures 7(a) and 7(b) to an open position as shown in Figures 7(c) and 7(d), opening the tip opening 132c1 of the bucket body 132, and transitioning to a state in which this tip opening 132c1 is connected to the innermost part of the water receiving space 132b.

[0133] Here, the elastic biasing force of the biasing member biasing the wave receiving member 133 is a relatively weak force sufficient to lightly abut the wave receiving member 133 against the tip partition 132d, and because of this weak biasing force, even if the relative water flow 103 (relative backflow 103B) pushing against the opening operating surface 133b of the wave receiving member 133 from the tip opening 132c1 is a relatively weak flow, the wave receiving member 133 can easily be tilted around the swing axis 133c to open the tip opening 132c1.

[0134] Therefore, with the wave receiving bucket 131, when the relative water flow 103 (relative reverse flow 103B) flowing toward the tip surface 132c of the bucket body 132 collides with the opening operating surface 133b of the wave receiving member 133 through the tip opening 132c1, this relative water flow 103 (relative reverse flow 103B) pushes the opening operating surface 133b of the wave receiving member 133 toward the inside of the bucket body 132 so as to resist the biasing force of the biasing member, and the wave receiving member 133 is rotated around the swing axis 133c, and tilted (moved) in the counter biasing direction of the biasing member (the opposite direction of the solid arrow in Figures 7(a) and 7(b)).

[0135] As a result, the relative water flow 103 (referring to the relative water flow 103 (relative reverse flow 103B) in the direction indicated by the white arrows in Figures 7(c) and 7(d)) ​​that would hinder the forward rotation of the wave receiving rotor 130, i.e., the relative water flow 103 (relative reverse flow 103B) that is about to collide with the tip surface 132c of the bucket body 132, can be caused to pass directly through the wave receiving bucket 131 from the tip opening 132c1 through the water receiving space 132b to the base end opening 132a1 by pushing down the wave receiving member 133 and causing it to assume a tilted position (position in the open position), thereby preventing the relative water flow 103 (relative reverse flow 103B) from directly colliding with the tip of the wave receiving bucket 131 and becoming resistance that would hinder the forward rotation of the wave receiving rotor 130.

[0136] Thus, according to the wave receiving rotor 130 of the second embodiment, as shown in Figures 7(a) and 7(b), the relative water flow 103 (relative forward flow 103A (white arrows in Figures 7(a) and 7(b))) flowing toward the base end opening 132a1 of the wave receiving bucket 131, i.e., the relative water flow 103 (relative forward flow 103A) that attempts to rotate the wave receiving rotor 130 in the forward direction, is received by the wave receiving surface 133a of the wave receiving member 133 within the water receiving space 132b of the bucket body 132, and can be converted into a rotational force that rotates the wave receiving rotor 130 in the forward direction.

[0137] On the other hand, according to the wave receiving rotor 130 of the second embodiment, as shown in FIGS. 7(c) and 7(d), the relative water flow 103 (relative reverse flow 103B ((white arrows in FIGS. 7(c) and 7(d)))) flowing toward the tip of the wave receiving bucket 131, i.e., the relative water flow 103 (relative reverse flow 103B) that tries to reverse the wave receiving rotor 130, hinders the forward rotation of the wave receiving rotor 130 in the first place. Therefore, in order to reduce the resistance of the relative water flow 103 (relative reverse flow 103B), the relative The force of the water flow 103 (relative reverse flow 103B) is used to tilt the wave receiving member 133 around the swing axis 133c to open the tip opening 132c1, and the relative water flow 103 (relative reverse flow 103B) is then allowed to pass through the water receiving space 132b from the tip opening 132c1 and escape through the base end opening 132a1, thereby reducing the resistance that the wave receiving bucket 131 receives from the water underwater 102, reducing the resistance force that the wave receiving rotor 130 receives from the water underwater 102, which inhibits the forward rotation of the wave receiving rotor 130, and promoting the forward rotation of the wave receiving rotor 130.

[0138] Here, the water passage 132e, which is a flow path formed by connecting the tip opening 132c1, the water receiving space 132b, and the base end opening 132a1 and penetrating from the base end face 132a to the tip end face 132c of the bucket body 132, is a flow path that is opened and closed by the wave receiving member 133 acting as an opening and closing valve.

[0139] Furthermore, when the strength of the relative backward flow 103A decreases and becomes weaker than the biasing force of the biasing member, the biasing force of the biasing member causes the wave receiving member 133 to return from the tilted open position (the position of the wave receiving member 133 shown in Figures 7(c) and 7(d)) ​​to the inverted closed position (the position of the wave receiving member 133 shown in Figures 7(a) and 7(b)), and the water passage 132e is blocked by the wave receiving member 133 returned to this closed position. As a result, the wave receiving surface 133a of the wave receiving member 133 is returned to a state where it can receive the relative forward flow 103B.

[0140] As shown in Figure 6, the wave receiving rotor 130 is in a state where all of the multiple wave receiving buckets 131 are submerged in the water 102 when the float (not shown) is floating on the water surface, and of the submerged wave receiving buckets 131, four wave receiving buckets 131 are positioned at a first position P1 where their wave receiving surfaces 133a face downward, a second position P2 where their wave receiving surfaces 133a face sideways (towards the rear of the float (right side in Figure 6)), a third position P3 where their wave receiving surfaces 133a face upward, and a fourth position P4 where their wave receiving surfaces 133a face sideways (towards the front of the float (left side in Figure 6)).

[0141] Here, according to the wave power generation unit of this second embodiment, similarly to the wave power generation unit 1 of the first embodiment, even when subjected to the swaying motion of water surface waves and the rocking motion of the float, all or most of the multiple wave receiving rotors 130 remain submerged in the water 102, and in particular, the wave receiving buckets 131 located at the first position P1, the third position P3 and the second position P2 are constantly maintained submerged in the water 102 regardless of the water surface waves and the rocking motion of the float.

[0142] As shown in FIG. 6, among the multiple wave receiving buckets 131 submerged in the water 102, at least the wave receiving bucket 131P1 at the first position P1 has its wave receiving surface 133a facing downward, and the wave receiving bucket 131P2 at the second position P2 rotated approximately 90° from the first position P1 in the reverse direction around the axis of the rotation shaft 33 has its wave receiving surface 133a facing sideways (towards the rear of the float (to the right in FIG. 6)). The wave receiving bucket 131P3, which is at a third position P3 and has rotated approximately 90° in the reverse direction around the center, receives the relative water flows 103a-103d generated in the water 102 with its downward-facing wave receiving surface 133a, and the wave receiving bucket 131P4, which is at a fourth position P4 and has rotated approximately 90° in the reverse direction from the third position P3 around the axis of the rotation shaft 33 with its sideways (facing forward of the float (left side in Figure 6)) wave receiving surface 133a, and each applies a rotational force to the rotating main body 31.

[0143] In other words, the wave receiving rotor 130 is arranged so that the wave receiving surface 133a of the wave receiving bucket 131P1 at the first position P1 receives the relative water flow 103a, the wave receiving surface 133a of the wave receiving bucket 131P2 at the second position P2 receives the relative water flow 103b, the wave receiving surface 133a of the wave receiving bucket 131P3 at the third position P3 receives the relative water flow 103c, and the wave receiving surface 133a of the wave receiving bucket 131P4 at the fourth position P4 receives the relative water flow 103d.

[0144] Therefore, with the multiple wave receiving buckets 131, the wave receiving surface 133a of the wave receiving bucket 131P1 at the first position P1 faces downward and is pushed by the upward relative water flow 103a, the wave receiving surface 133a of the wave receiving bucket 131P2 at the second position P2 faces sideways (towards the rear of the float (right side in FIG. 6)) and is pushed by the sideways relative water flow 103b (water flow coming relatively from the rear of the float (right side in FIG. 6)), and the wave receiving surface 133a of the wave receiving bucket 131P3 at the third position P3 faces upward and is pushed by the downward relative water flow 103b. c, and the wave receiving surface 133a of the wave receiving bucket 131P4 at the fourth position P4 turns sideways (facing forward of the float 2 (left side in Figure 6), i.e., facing the opposite direction to the wave receiving surface 133a of the wave receiving bucket 131P2 at the second position P2) and is pushed by the relative water flow 103d that is sideways (water flow coming relatively from the front of the float 2, i.e., in the opposite direction to the sideways relative water flow 103b received by the wave receiving surface 133a of the wave receiving bucket 131P2 at the second position P2), causing the wave receiving rotor 130 to rotate in the forward direction.

[0145] The present invention has been described above based on an embodiment, but the present invention is not limited to the above embodiment, and it can be easily inferred that various improvements and modifications are possible within the scope of the present invention.

[0146] For example, in this embodiment, all of the wave receiving rotors 3 are mounted on the floating body 2 so as to be submerged in the water 102 when the water surface 100 is horizontal, but the positions at which the wave receiving rotors 3 are mounted are not necessarily limited to this, and any mode will do as long as at least both the wave receiving buckets 32 at the first position P1 and the second position P2 are submerged in the water 102 when the water surface 100 is horizontal. Note that, when the wave receiving bucket 32 ​​at the first position P1 is submerged in this way, it is obvious that the wave receiving bucket 32 ​​at the third position P3, which is point-symmetrical to the first position P1, will also be submerged when the water surface 100 is horizontal.

[0147] Furthermore, in this embodiment, the form of the float 2 has been described as being in the form of a hull, but the form of the float is not necessarily limited to a hull, and may be, for example, any of the various forms used in floating structures for offshore wind power generation or other forms.

[0148] In addition, in this embodiment, a speed increaser 41 and a flywheel 42 are used as the connecting transmission mechanism 4, and these speed increaser 41 and flywheel 42 are interposed between the rotating shaft 33 of the wave receiving rotor 3 and the rotor part 51 of the generator 5 to connect the two, but the form of the connecting transmission mechanism is not necessarily limited to this.

[0149] For example, in addition to the speed increaser 41 and the flywheel 42, a friction plate type electromagnetic clutch may be provided as a connecting transmission mechanism, and this electromagnetic clutch may be provided between the speed increaser 41 and the flywheel 42. Then, depending on the rotational movement of the receiving rotor 3, the rotor part 51 of the generator 5 or the flywheel 42 may be connected to the speed increaser 41, or the flywheel 42 and the generator 5 (rotor part 51) may be disconnected from the speed increaser 41 as appropriate.

[0150] For example, by doing this, when the rotational speed of the flywheel 42 is faster than that of the wave-receiving rotor 3, the electromagnetic clutch can be disengaged and the rotor part 51 of the generator 5 can be rotated by the rotational inertia force of the flywheel 42 to generate electricity, and also, in the unlikely event that the wave-receiving rotor 3 rotates in the reverse direction, the electromagnetic clutch can be disengaged and the rotor part 51 of the generator 5 can be rotated by the rotational inertia force of the flywheel 42 to generate electricity.

[0151] Furthermore, with a friction plate type electromagnetic clutch, rotational force is transmitted from the driving shaft to the driven shaft via the frictional force between the friction plates that abut against each other, and by moving these friction plates away from each other, the driving shaft side and the driven shaft side are separated, thereby blocking the transmission of rotation of the driving shaft to the driven shaft, so that by adjusting the contact state between these friction plates to create a half-clutch state, it is possible to smoothly connect the speed increaser 41 and the generator 5. In particular, when there is a speed difference between the rotational speed of the high-speed output shaft 41b of the speed increaser 41 and the rotational speed of the flywheel 42, connecting both friction plates using the half-clutch state enables a smooth connection operation.

[0152] Furthermore, the embodiment of the coupling transmission mechanism is not necessarily limited to the above-described embodiment, and for example, the rotating shaft 33 of the wave receiving rotor 3 may be coupled to the low-speed input shaft 41a of the speed increaser 41, and the rotor part 51 of the generator 5 may be coupled to the high-speed output shaft 41b of the speed increaser 41. In other words, the rotating shaft 33 of the wave receiving rotor 3 and the rotor part 51 of the generator 5 may be coupled in a manner in which only the speed increaser 41 is interposed between them.

[0153] In addition, in this embodiment, a conical shape is adopted as the external shape of the wave-receiving bucket 32, but this is not necessarily limited to a conical shape and other shapes are also possible, for example, a frustum shape. Furthermore, the shape of the wave-receiving surface is not necessarily limited to a conical recess, and may be any concave shape that easily receives the relative water flow, for example, a frustum-shaped recess, a spherical recess, a bowl-shaped recess, or a recess of another shape.

[0154] Furthermore, in this embodiment, a total of four wave receiving rotors 3 are provided on the front, rear, left and right sides of the floating body 2, but the number of wave receiving rotors 3 mounted on one floating body 2 and their arrangement are not necessarily limited to this, and for example, a total of more than four wave receiving rotors 3 may be provided on the floating body 2. Furthermore, in this embodiment, one wave receiving rotor 3 is provided for each rotation shaft 33, but in a different embodiment, for example, two or more wave receiving rotors 3 may be provided side by side on the same axis for one rotation shaft 33.

[0155] Furthermore, in this embodiment, one wave receiving rotor 3 is provided on each side of the bow 21 and stern 22 of the float 2, but in other embodiments, for example, one wave receiving rotor 3 is provided on each of the port side 23 and starboard side 24 of the float 2 as a whole, and further, two or more wave receiving rotors 3 may be arranged side by side on the same rotation axis 33 on the port side 23 of the float 2, or two or more wave receiving rotors 3 may be arranged side by side on the same rotation axis 33 on the starboard side 24 of the float 2.

[0156] In addition, in this embodiment, a total of eight receiving buckets 32 are provided on each receiving rotor 3, but different embodiments may be used, for example, a total of more than eight receiving buckets 32 may be provided on each receiving rotor 3.

[0157] Furthermore, in the second embodiment, the wave receiving member 133 is biased by a biasing member to place the wave receiving member 133 in a closed state, but the wave receiving member 133 does not necessarily need to be biased by a biasing member, and may be a member that opens and closes only by the flow force of the relative water flow 103. In this case, when the wave receiving member 133 receives the flow force of the relative forward flow 103A, the wave receiving member 133 is pushed and moved from the open position to the closed position, and when the wave receiving member 133 receives the flow force of the relative backward flow 103B, the wave receiving member 133 is pushed and moved from the closed position to the open position. [Explanation of symbols]

[0158] 1 Wave power generation unit 2 Floating body 3 Receiving rotor 4. Linked transmission mechanism 5. Generator 6 Mooring members 8 Heavy objects 31 Rotating main body 32 Receiving bucket 32P1 Receiving bucket in first position 32P2 Receiving bucket in second position 32P3 Receiving bucket in third position 32P4 Receiving bucket in fourth position 32a Point 32b,133a Receiving surface 32c Pointed outer surface 33 Rotation axis 51 Rotor section 100 water surface 101 Water surface waves 102 Underwater 103 Relative Water Flow 103a Relative water flow received by the receiving surface of the receiving bucket in the first position 103b Relative water flow received by the receiving surface of the receiving bucket in the second position 103c Relative water flow received by the receiving surface of the receiving bucket in the third position 103d Relative water flow received by the receiving surface of the receiving bucket in the fourth position 103A Relative forward flow 103B Relative reflux 104 Underwater 130 Second embodiment of the receiving rotor 131 Wave receiving bucket of the second embodiment 131P1 Wave receiving bucket of the second embodiment in the first position 131P2 Wave receiving bucket of the second embodiment in the second position 131P3 Wave receiving bucket of the second embodiment in the third position 131P4 Wave receiving bucket of the second embodiment in the fourth position 132 Bucket body 132a Base end surface (part of the base end of the bucket body) 132a1 Base end opening (part of the base end of the bucket body, part of the water passage) 132b Receiving space (part of the waterway) 132c Tip surface (part of the tip of the bucket body) 132c1 Tip opening (part of the tip of the bucket body, part of the water passage) 132d Tip bulkhead (part of the base end of the bucket body) 132e Waterway (waterway) 133 Wave receiving member 133a Receiving surface 133b Opening operation surface 133c Oscillating shaft P1 1st position P2 2nd position P3 3rd position P4 4th position Pitch circle

Claims

1. A wave power generation unit for a wave power generation system that generates power using water surface waves generated on an offshore water surface, a floating body that can float on the water surface where water surface waves are generated by buoyancy and that moves in the directions of the axes of a spatially fixed coordinate system and rotates around the axes in response to the water surface waves, thereby swaying and freely rocking on the water surface; The floating structure is provided with a rotating body that is rotatably supported on the floating body via a rotating shaft and is integrated with the rotating shaft, a plurality of wave-receiving buckets provided on the entire outer periphery of the rotating body, and a wave-receiving rotor that is formed in a waterwheel shape and has a wave-receiving surface formed on each of the wave-receiving buckets that receives water surface waves, and that uses the rotation of the rotating shaft to rotate a rotor of a generator, The wave receiving rotor is The floating body is floating on the water surface and at least a portion of the plurality of wave receiving buckets is submerged in water, The wave receiving bucket in the submerged portion is A wave power generation unit characterized in that the wave receiving surface receives relative water currents generated in the water at a first position where the wave receiving surface faces downward, and at a second position, which is a position rotated from the first position around the axis of the rotation shaft and where the wave receiving surface faces sideways, thereby imparting a rotational force to the rotating main body.

2. The plurality of wave receiving buckets include: the rotary shaft is provided on the rotary main body at regular intervals on a pitch circle having the axis of the rotary shaft as its center, a pointed end portion that is pointed toward the forward rotation direction of the rotating main body portion; the wave-receiving surface facing the opposite direction from the tip and having a concave shape toward the tip; 2. The wave power generation unit according to claim 1, further comprising a pointed outer peripheral surface whose outer diameter gradually decreases from the wave receiving surface toward the pointed end.

3. The wave receiving bucket is bucket bodies provided on the rotating body portion at regular intervals on a pitch circle centered on the axis of the rotating shaft; a tip end of the bucket body facing the forward rotation direction of the rotating body part; a base end portion of the bucket body facing the inversion direction of the rotating body portion, opposite to the tip end portion; a water passage that is a flow path provided through the inside of the bucket body from a base end portion to a tip end portion of the bucket body; an on-off valve formed to be freely movable between one of a closed position in which the water passage is closed and an open position in which the water passage is open, and the other, and the valve has a wave-receiving surface that receives, at the closed position, a relative water flow that flows relatively from the base end side of the bucket body toward the tip end side thereof (hereinafter referred to as a "relative forward flow"), and a wave-receiving member that receives a relative water flow that flows relatively in the opposite direction to the relative forward flow (hereinafter referred to as a "relative reverse flow") and moves from the closed position to the open position; The wave receiving member is The wave-receiving surface receives the relative forward flow at the closed position, and converts the force accompanying the flow of the relative forward flow into a rotational force for rotating the rotating main body in the forward direction.

2. A wave power generation unit as described in claim 1, characterized in that the wave receiving member receives a relative backflow at the closed position, thereby moving the wave receiving member from the closed position to the open position and opening the water passage, and the relative backflow is allowed to pass through the inside of the bucket body through this opened water passage and escape, reducing the underwater resistance experienced by the bucket body.

4. A wave power generation unit as described in any one of claims 1 to 3, characterized in that one end is anchored to the float and the other end is anchored to the bottom of the water itself or a heavy object placed on the bottom of the water, and a mooring member is provided to moor the float at a fixed location.

5. A wave power generation system comprising: a wave power generation unit according to any one of claims 1 to 3; power transmission means for transmitting the power generated by the wave power generation unit; and power equipment for receiving the power transmitted by the power transmission means.

6. A wave power generation system comprising: a wave power generation unit according to claim 4; power transmission means for transmitting the power generated by the wave power generation unit; and power equipment for receiving the power transmitted by the power transmission means.

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