JP2013036365A - Ocean energy power generation system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ocean current and tidal current wave power generation system which can sensitively and optimally respond to complicated motions of ocean currents and tidal currents in a wide range and has a large size and outputs high power with high efficiency and is economical.SOLUTION: Rotary disks 11, 12 are mounted with a large number of current-receiving blades 3 which have faces in a vertical direction and are arranged in a passive variable pitch or a fixed pitch of a lifting force generation type or an active variable pitch. The rotary disks are installed in a horizontal direction near the water surface or tethered to float, and made to rotate by acquiring a propelling force in the same direction from motions of ocean currents and tidal currents as an energy source, and thereby, energy is absorbed from the rotation. By mounting a large number of current-receiving blades on segmented positions, it is possible to respond with an independent and optimal form in each segment to a water flow that always changes in accordance with the motion directions and flow velocities of ocean currents and tidal currents and influences of other blades, and as the whole apparatus, a current receiving cross-sectional area with respect to ocean currents and tidal currents can be increased in size and the structure can be simplified.

Description

The present invention relates to an ocean current / tidal current power generation system using ocean energy.

Power generation using natural energy is a power generation method that does not rely on fossil fuels, and it has great expectations such as prevention of global warming, measures against uneven distribution of resources, and effects of economic levitation.

As power generation using ocean energy, there are ocean current power generation, tidal current power generation, wave power generation, temperature difference power generation, and the like, but their existing amounts are large. Among them, ocean currents and tidal currents are limited in the area where they exist compared to waves, but the energy density is large and has great utility value.
However, the ocean current power generation and tidal current power generation methods that have been proposed in the past are small in scale, difficult to install, high in power generation cost, and not sufficient for practical use at a large commercial level.

In order to promote practical application, it is essential to increase the size and increase the efficiency from the technical aspect and to reduce the construction cost and power generation cost from the cost aspect.

Ocean currents are oceanic circulations caused by winds such as westerly winds, and flow in almost constant directions. However, the point where the ocean current is strong is several kilometers away from the land, and it is difficult to install and manage the equipment because of the deep water depth, and it was difficult to realize the power generation system with the conventional method similar to tidal current power generation.

Tidal current power generation uses the flow caused by tidal currents, and the location where the tidal current can be used is relatively close to the land, making it easier to install a power generation system than ocean currents. However, the direction of flow is reversed twice a day.

Examples of conventional ocean current and tidal current power generation methods are as follows.

One is classified as a horizontal axis turbine. A typical example is a propeller type, and the wings installed in the water rotate in response to the flow of ocean currents and tidal currents to drive the generator.

The other is classified as a vertical axis turbine, and examples include Darius type and Savonius type.

However, these methods are difficult to increase the size of the propeller, are difficult to install, and it is difficult to increase the size of the power generation system at low cost.

JP2011-117397A

"NEDO Renewable Energy Technology White Paper" New Energy and Industrial Technology Development Organization (NEDO) December 2010

The problem to be solved by the present invention is to provide an efficient large-scale and large-output economical ocean current and tidal current power generation system.

Specifically, the receiving cross-sectional area or the receiving line length for ocean currents and tidal currents is increased, the ocean currents that change in the direction and size of movement, the method capable of finely responding to tidal currents, and the high efficiency of energy absorption. Is to realize.

In addition, it is to provide a system with low construction costs, maintenance costs, and power generation costs, including the equipment itself, and to realize a system that is simple in structure, easy to manufacture, transport, and install, especially ocean currents and tidal currents. It is to realize the simplification of the installation offshore where the installation area can be large.

In order to achieve the above object, the present invention provides the following means.

The ocean current and tidal current power generation method according to the present invention is a method of turning a rotary disk equipped with a plurality of passive variable pitches whose vertical direction is vertical, a large number of lift generating fixed pitches or a large number of active variable pitch receiving vanes near the water surface. It is installed in the horizontal direction or is levitated and tethered, and it is rotated by obtaining a propulsive force from the ocean current and tidal motion that are energy sources, and absorbs energy from this rotation.

According to the present invention, by installing a large number of receiving wings at the segmented positions, independent and optimal features for each segment with respect to the ocean currents and the water currents that constantly change in the direction and size of the tidal currents. The system as a whole can handle a wide range of ocean currents and complex tidal currents in a fine and optimal manner.

According to the present invention, the direction of the ocean current and the tidal current can be adjusted by making each receiving blade installed in the vertical direction a passive variable pitch type, an active variable pitch type, or a lift generating type fixed pitch. Even if it changes with time and position, the rotational propulsion direction of the disk by the ocean current and tidal current is the same, and the rotational movement in the same direction is performed.

According to the present invention, the entire apparatus may be a bottomed type or a tethered floating type, has a high degree of freedom in selecting an installation location, and is easy to carry and install. In particular, ocean currents and tidal currents are large, enabling installation offshore with a large footprint.

According to the present invention, the structure of a wide rotating disk can be simplified, an appropriate buoyancy can be given, and it is not necessary to make a strong structure to resist gravity, and it is possible to increase the size with a simple structure. To do.

The following effects are produced by the present invention.

By installing each receiving blade installed in the vertical direction to a passive variable pitch type, or an active variable pitch type, and a lift generating type fixed pitch receiving blade at a segmented position, It is possible to respond to wave currents that constantly change in the direction and size of tidal currents in an independent and optimal form for each section, and the entire device can be optimally adapted to a wide range of ocean currents and complex tidal currents.

In addition, even if the direction of the ocean current and tidal current changes depending on the time and position, the receiving blades have the same rotational propulsion direction of the disk due to the ocean current and tidal current. realizable.

In addition, a wide rotating disk has a simple structure, can give an appropriate buoyancy, and does not need to be a strong structure to resist gravity, and can be easily increased in size.

In addition, since the entire apparatus can be a floating type that is anchored as well as a bottomed type, the degree of freedom in selecting the installation location is large, and transportation and installation are easy. In particular, it can be expected to generate large-scale power generation with large ocean currents and tidal currents, and can be installed offshore with a large installation area. The fishery problem can be avoided.

Moreover, since the rotating disk is almost near or below the surface of the water, it does not cause noise problems such as wind power generation, bird crash death problems, and landscape problems. Since the rotating speed of the rotating disk is not as high as that of wind power generation wings, there is little possibility of causing damage due to centrifugal force and collision death of marine animals.

If this rotating disk is installed near the water surface, energy can be absorbed not only from ocean currents and tidal currents but also from waves near the water surface. Moreover, as will be described later, the amount of absorption can generate more energy than the sum of the amount of energy absorbed from only ocean currents and tidal currents and the amount of energy absorbed only from waves.

Regarding power generation methods using energy from waves, there are Patent Document 1 and Japanese Patent Application Laid-Open No. 2011-117397 (hereinafter referred to as Patent Documents) which are the inventors' invention.
In the method of the patent document, the receiving wing is not in the vertical direction, and it is not possible to absorb the ocean current and tidal current energy which are horizontal flows according to the present invention. Or inefficient.
In addition, the method disclosed in the patent document cannot provide a synergistic effect between ocean current, tidal current energy and wave energy.

On the other hand, in the present invention, the receiving vanes are installed in the vertical direction, and thereby can absorb energy from ocean currents and tidal currents that are horizontal flows.
Further, in the shape of the present invention, since the ocean current, tidal current and wave motion are simultaneously applied to the receiving blade at the same place, energy is added in a form proportional to the cube of the flow velocity added to the receiving blade. There is an effect more than the amount added individually, and the synergistic effect of ocean current, tidal current and wave motion is obtained.

FIG. 1 is an overall view showing an embodiment. FIG. 2 is an enlarged view showing the embodiment. It is a side view. FIG. 3 is an enlarged view of a part of the rotating disk of the embodiment. Furthermore, it is on an enlarged view. FIG. 4 is a top view of the embodiment. FIG. 5 is a side view of the embodiment. FIG. 6 is an external view of the receiving vane of the embodiment. FIG. 7 is an explanatory view showing the pitch change of the receiving blade. FIG. 8 is an explanatory diagram showing a force vector applied to the receiving blade. FIG. 9 is an explanatory diagram for showing numerical examination. FIG. 10 is an explanatory diagram showing a force vector applied to the receiving blade. FIG. 11 is an explanatory view showing a pitch change of the receiving blade. FIG. 12 is an explanatory view showing a pitch change of the embodiment.

A rotating disk equipped with a number of receiving wings whose vertical direction is the vertical direction described in the means for solving the above problems is installed in a horizontal direction near the water surface, or is levitated and tethered to the ocean current as an energy source, An example in which a propulsive force is obtained from the tidal current and rotated to absorb energy from the rotation is as follows.

FIG. 1 is an overall view showing an embodiment of the first embodiment. In FIG. 1, the entire structure has two rotating discs 11 and 12 that rotate in opposite directions due to the movement of ocean currents and tidal currents installed in the horizontal direction near the water surface, and a large number of receiving vanes 3 are attached to each rotating disc. Each wing 3 obtains a propulsive force by the ocean current and tidal current and rotates the rotating disk. The shaft structure 5 of the rotating disk is supported by the support structure 2.

The support structure 2 is anchored to the seabed or land with anchors 1 and chains 13. The turntable and the support structure are subjected to a force in the downstream direction by the ocean current and tidal current, but remain in place without being swept away by the anchor 1 and the chain 13. As a result, the rotating disk receives a horizontal flow pressure along the flow, and this flow pressure rotates the rotating disk as will be described later.

The two rotating disks receive the forces of ocean currents and tidal currents and rotate in opposite directions to generate counter-forces of opposite forces, but the moments of each force are transmitted to the support structure 2 through the shaft structure 5, The rotational moment received by each turntable is canceled out, and the support structure itself does not rotate and supports a stable power generation operation.

FIG. 2 is an enlarged view of the overall view of FIG. The shaft structure 5 includes a rotor 51 and a stator 52. The rotor is connected to a rotating disk and is driven to rotate by the rotating disk. The stator is fixed to the support structure 2 and does not rotate, and supports a stable power generation operation. The support structure 2 is tethered to the seabed or land via a chain 13. The chain 8 is connected to a buoy 14 which has buoyancy and is located on the sea surface, and prevents the entire equipment from being sunk or tilted by the gravity of the chain or the downward force of the tether.

The shaft structure 5 includes a speed increaser and a generator, and is driven by the rotation of the rotating disk to generate power.

The support structure has buoyancy, and this buoyancy can be adjusted to an appropriate amount by taking in and out air inside the support structure. As a result, the turntable is adjusted to the optimum vertical position for absorbing the ocean current and tidal current energy. It can also be raised to a height that is easy to work during construction and maintenance.

Also, when there are excessive winds and waves during a storm, it is lowered to a depth that has less influence to prevent it from being destroyed.

Further, when the vehicle is towed from another place at the time of construction or the like, the height is adjusted to be easily pulled.

As an energy collecting method, it is possible to drive a high-pressure fluid generating pump instead of the generator and use the high-pressure fluid generated here as an energy source.

FIG. 3 is an enlarged view of a part of the rotating disk. The rotating disk has a receiving vane 3 mounted on the frame 8 and receives the flow pressure from the ocean current and tidal current, and this serves as a rotational driving force to rotate the rotating disk.

FIG. 4 is a top view showing this embodiment. The entire device is anchored to the seabed or land with anchors 1 and chains 13 to prevent being swept away by current pressure from the ocean current, tidal current, and to allow the fluid pressure to be applied to the receiving wing.

FIG. 5 is a side view showing the present embodiment. As shown in the figure, the rotating disks 11 and 12 and the receiving blades are located immediately below the water surface 6 and receive a flow pressure due to the movement of ocean currents and tidal currents. The whole structure is a floating type, and is anchored to the seabed 9 by anchors 1 and chains. When the force applied to the anchor is large, the anchor is fixed to the anchoring structure installed on the seabed or on the land. A steel wire having a large tensile strength may be used instead of the chain.

Also, with this structure, the support structure does not need to be fixed to the seabed 7 and may be a floating body, which simplifies the structure and enables installation offshore.

When the water depth is shallow and the construction is simple and a simple structure with a single rotating disk is desirable, a method of fixing the fixed axis of the rotating disk to the seabed (bottomed) may be used. In this case, since the moment of force as a reaction when the rotating disk rotates is supported by a fixed shaft fixed to the seabed, the support structure 2 shown in FIG. 1 is unnecessary. Moreover, the rotating disk may be independent and the whole structure becomes simple.

The generated electric power or generated high-pressure fluid is sent to land for use by transmission lines or pipes installed along the seabed or in the sea. This transmission line or pipe can be bundled with the above-mentioned chain to keep the strength. If the depth of water is deep and it is difficult to install the anchor, it will be fixed with the transmission line or pipe to the land or to a shallow depth.

Furthermore, when the installation site is offshore and it is difficult to extend the transmission line or pipe to the land, there is also a method of charging a large-sized battery with the generated power and transporting it to a use site by a ship or the like. Alternatively, there is a method in which a substance that can store energy such as hydrogen is generated by the generated electric power and transported to a place of use by a ship or the like.

FIG. 6 shows the external appearance of an embodiment of the single receiving blade 3. The receiving blade 3 has a rotating shaft 31 and is connected to the frame 8 of FIG. The pitch of the receiving blade changes around this rotation axis. The rotating shaft has elasticity in the direction of rotation, and the angle of the receiving blade, that is, the pitch, changes as the current pressure of the ocean current and tidal current is applied to the receiving blade. That is, the pitch of the receiving vanes changes passively.

FIG. 7 is an explanatory view showing the deformation of the receiving wing due to the movement of the ocean current and tidal current. When wave water flows from the bottom to the top of the figure, the receiving blade receives force in the upward direction, the elastic receiving blade deforms upward, and the water flow receives force in the left direction in the figure. . When the water current direction of the wave is from the top to the bottom, the elastic portion is deformed downward and receives a force in the left direction of the figure by the water flow. That is, regardless of the direction of wave water flow, each receiving blade receives a driving force in the left direction of the figure and travels in the left direction. Since the actual receiving vanes are arranged concentrically on the rotating disk, the propulsive force received by the receiving vanes acts in the direction of rotating the rotating disk in the same direction.

FIG. 8 shows, as a vector, the force that the receiving wing receives from the wave current, tidal current, and wave current. The receiving wing receives a force Fo in a direction perpendicular to the wing surface due to water flow. Fo is decomposed into a direction Fb perpendicular to the rotating disk and a direction Fa horizontal. Fa is directed to the left in the figure regardless of the direction of water flow, and is the force that propels the rotating disk in the same direction.

The numerical examination is shown below.

  FIG. 9 is a vector diagram for a rough quantitative explanation. In the figure, the horizontal line represents the rotating disk, and the diagonal line represents the receiving blade.

In the figure, each parameter and variable are defined as follows.
Fo: Force applied to the receiving wing by waves
Fa: Horizontal force on the receiving wing (traveling propulsion force)
Fb: Normal force applied to the receiving blade (non-running force)
Vc: Vertical component velocity of wave motion
Va: Receiving blade travel speed
Vd: Wave speed equivalent deceleration by receiving blade travel
So: receiving blade area θ: pitch angle of receiving blade ρ: weight density of water
P: Energy available per hour (power generation)

First, the force Fo applied to the receiving wing by waves is
Fo = ρSo (Vc − Vd) ^{2 =} ρSo (Vc − Va sinθ) ² ---------- (1)
It becomes.
Here, the wave velocity equivalent deceleration Vd due to running of the receiving blade is
Vd =
Va sinθ
--------- (2)
It is represented by

The driving force Fa received by the receiving blade is
Fa = Fo sinθ = ρSo (Vc − Va sinθ) ² sinθ -----------
(3)
The available energy per hour P generated in the receiving blade is
P = Va Fa = ρSo Va (Vc −Va sinθ) ² sinθ ----------- (4)
It becomes.

Where k is the wave velocity equivalent deceleration coefficient
k
= Vd / Vc = Va sinθ / Vc -------------------------- (5)
Then,
P = ρSo Vc ³ (1− k) ² k ---------- (6)
It becomes.

Differentiating P by k to find the maximum value of P, P is maximum when k = 1/3.
P, that is, the maximum value of power generation is Pmax, and the value of (1−k) ² k is μa = 0.148
-------------- (7)
Next
Pmax = ρSo Vc ³ (1−k) ² k = ρμa So Vc ³ =
0.148ρSo Vc ³ ------------------ (8)
It becomes.

Specific numerical examples are as follows.
When the ocean current and tidal current velocity Vc is 2.5 m / s, the outer diameter Ra of the rotating disk is 100 m, the number of receiving blade stages arranged concentrically is 4 inner diameter Rb is 70 m, and the height of the receiving blade is 5 m. Receiving blade total area Sa
Sa = 2πh (Ra / 2) (1 + 0.9 + 0.8 + 0.7)
= 5,341m ² ------------------ (9)

Assuming that the ocean current and tidal current come from one direction, the effective area So of the receiving wing that the wave receives is half of Sa,
So = Sa / 2 = 2,670m ² --------- (10)
It becomes.

As shown in Equation (7), the maximum efficiency μa for absorbing the energy of the ocean current and tidal current with the receiving wing is 0.148.
Power generation efficiency μg considering other losses
μg = 0.4
---------- (11)
And the weight density of seawater is 1,025 kg /
Assuming m ³ , the maximum power generation Pmax is
Pmax = ρSo Vc ³ (1−k) ² k = ρμgμa So Vc ³ = 0.044ρSo Vc ³ = 1,882KW ---------- (12)

It becomes.

When there are two rotor blades, the power generation amount is 3,764KW, twice that amount, and when there are N rotor blades, it is N times.

  Actual power generation has many complicated factors such as wing shape, complex wave shape and period, seasonal changes, overlapping of different waves, and specific power generation efficiency, and it is not easy to estimate accurately. However, the above value is a rough estimation example.

In the actual ocean, wave motions exist along with ocean currents and tidal currents. The receiving wing is subject to wave motion as well as ocean current and tidal current motion. The receiving blade also absorbs this wave energy in a complex manner.
Since the energy to be absorbed is proportional to the cube of the seawater velocity corresponding to the receiving blade, the energy to be absorbed is not simply added in a linear manner, but is added at a value higher than that and has a synergistic effect.

If the current velocity of ocean current and tidal current is a and the amplitude of wave velocity is b, the added velocity Ve is
Ve = a + bsin (2πt / T + θ) ---------- (13)
It becomes. Here, T is the wave period, and θ is a constant, which is zero here.

海流、潮流の流速aを2.5m/s、波浪の流速の振幅bを2.0m/sとすると、μcは2.03となる。
すなわち波浪が加わった場合には、加わらない場合の2.03倍もの発電量が発生する。相乗効果は大きい。 Since the absorbed energy is proportional to the cube of Ve, the ratio of the absorbed energy when the wave is added and not added is μc,

If the current velocity a of ocean current and tidal current is 2.5 m / s and the amplitude b of wave current velocity is 2.0 m / s, μc is 2.03.
In other words, when waves are added, the amount of power generation is 2.03 times as much as when no waves are added. The synergistic effect is great.

海流、潮流の流速aを2.5m/s、波浪の流速の振幅bを2.0m/sとすると、μsは1.13となる。
すなわち海流、潮流と波浪が別の所に当たり、相乗効果がない場合は、吸収エネルギー比μsは1.13(13%増)に過ぎず、前記の波浪が相乗効果として加わった場合のμcの2.03(103%増)が如何に大きいかが分かる。 If the ocean currents, tidal currents and waves are in different locations and there is no synergistic effect, and the power generation by ocean currents and tidal currents and the power generation by waves are simply added, the ratio of the absorbed energy when the waves are added and not added μs is

If the current flow velocity a of ocean current and tidal current is 2.5 m / s and the amplitude b of wave current velocity is 2.0 m / s, μs is 1.13.
In other words, when the ocean current, tidal current and waves are in different places and there is no synergistic effect, the absorbed energy ratio μs is only 1.13 (13% increase), and 2.03 (103 of μc when the waves are added as a synergistic effect. You can see how big (% increase) is.

In the above numerical example, the ratio of μs taking into account the synergistic effect and μs not taking into consideration is 2.1, and the synergistic effect when the ocean current, tidal current and wave are combined is more than twice.
In the actual marine environment, the above-mentioned synergistic effect occurs in the movement of ocean currents, tidal currents and waves, so it can be said that the effect of power generation combining ocean currents, tidal currents and waves is extremely large.

This ocean current and tidal current power generation method is installed horizontally on the ocean as a whole facility, so it can include ocean currents, tidal currents, and waves, and it is an efficient ocean energy power generation method that has a comprehensive synergistic effect. Can be used as

There are three forms of changes in the pitch of the receiving blade. In any form, the receiving blade receives the propulsive force in the same direction regardless of the direction of movement of the seawater.
The form of the first receiving blade pitch is passive in which the pitch angle is passively changed even if the pitch angle is not particularly controlled in response to the sea current and tidal current pressure described in the above embodiment and FIG. This is a variable pitch receiving blade. The pitch or angle of the receiving blade is deformed under the pressure of fluid motion.

For this purpose, the receiving blade material is made elastic or a spring is loaded on the shaft that supports the receiving blade to make it elastic. When the fluid contact speed is large and the fluid pressure is large, the amount of change in pitch (angle) increases, and the energy absorption efficiency increases.
However, if the pitch becomes larger than necessary, the flow pressure received by the receiving blades decreases, and conversely the energy absorption efficiency decreases. In other words, the pitch angle has an optimum value corresponding to the fluid velocity, as described in Equation 7 above.

The advantage of this passive variable pitch receiving blade is that there is no need to perform pitch control and the structure is simple, but the elastic force is set so that the pitch of each receiving blade is close to the optimum value. It is necessary.

The form of the second receiving blade pitch is a fixed pitch in which the pitch does not change. In the embodiment of the receiving blade of FIG. 6, if the shaft does not have elasticity and the pitch does not change even when there is a sea current or tidal current movement, a fixed pitch type receiving blade is obtained.

Depending on the shape of the receiving vane, the propulsive force in the same direction is always generated without changing the pitch. This is also called a Welsh turbine, and what is called Darius type in wind power generation uses this principle.

If a fixed pitch type receiving vane is applied to the method of the present invention, it is not necessary to change the pitch, so that the structure of the entire rotating disk equipped with the receiving vane can be strongly and simply. However, as a problem, generally, a Welsh turbine does not increase its propulsive force unless it exceeds a certain speed. For this reason, it is necessary to apply some kind of starting force at the time of initial startup. In general, a Welsh turbine-type blade is relatively thick and has a large resistance during rotation, which may reduce power generation efficiency.

FIG. 10 shows a vector diagram of the force applied to the fixed pitch type receiving blade.
In FIG. 10, the current receiving wing on the left side is subjected to the movement of ocean currents and tidal currents from the bottom to the top of the figure, resulting in lift Fo. This lift can be decomposed into a force Fb in the direction perpendicular to the receiving blade and a force Fa in the direction along the receiving blade. Fa is the force that propels the receiving wing to the left of the figure.
In FIG. 10, the current receiving wing on the right side is subjected to the movement of ocean currents and tidal currents from the top to the bottom of the figure, resulting in lift Fo. This lift can be decomposed into a force Fb in the direction perpendicular to the receiving blade and a force Fa in the direction along the receiving blade. Fa is the force that propels the receiving wing to the left of the figure.
In other words, regardless of the direction of the ocean current and tidal current applied to the receiving blade, the receiving blade receives the force propelled in the same left direction in the figure and propels the rotating disk in the same direction.

The advantage of using a fixed pitch type receiving blade is that the structure is simple and the receiving blade and the rotating disk are fixed, so that the structural strength is maintained. The problem is that the traveling speed of the receiving blade needs to be high to some extent in order to generate sufficient lift as described above. For this reason, an activation force may be required at an early stage when the rotating disk starts to move.

One method for generating the starting force is to combine the receiving blades mounted on the rotating disk with the variable pitch type receiving blades shown in FIG. 8 and the fixed pitch type receiving blades shown in FIG. How to equip. Since the variable pitch type receiving blade does not require the initial starting force, the variable pitch type receiving blade drives the rotating disk at the initial stage of starting, and the rotating speed of the rotating disk, that is, the traveling speed of the receiving blade. As the speed increases, the fixed-pitch driving force increases. Thereby, the advantage of a fixed pitch type receiving blade is maintained.

Another method of generating power is to give some elasticity to the rear of the fixed pitch type receiving blade, that is, the right rear portion of the receiving blade in FIG. By providing elasticity, the receiving wing receives the movement of the ocean current and tidal current and is deformed in a manner similar to the shape shown in FIG.

The form of the third receiving blade pitch is neither passive nor fixed, and is a method of actively controlling the pitch by providing each receiving blade with a pitch angle control mechanism. If the direction of the ocean current and tidal current is constant for a certain period of time, the pitch does not necessarily have to be changed passively in each section. Even if the pitch angle is actively controlled according to the direction of the entire ocean current and tidal current, good. That is, the pitch of each receiving blade is not changed by the flow pressure of the ocean current and tidal current, but the pitch angle is actively changed by a preset pitch control mechanism.

If the velocity and direction of the fluid are substantially constant, the optimum pitch angle is known in advance, and the pitch angle can be controlled to match this value. However, when applied to ocean currents and tidal currents, it is necessary to control the pitch according to the rotational position of the rotating disk.

Active pitch control technology is widely used in aircraft and ships, and is generally established as a technology.

FIG. 11 shows an example in which the pitch of the receiving blade is actively controlled when the direction of the ocean current and the tidal current is constant. In the figure, ocean currents and tidal currents flow from the top to the bottom of the figure. The pitch of the receiving blades is controlled to the angle shown in the figure at a position in the whole. As a result, the receiving blade receives the flow of ocean current and tidal current and drives the rotating disk counterclockwise.

The problem with active pitch-controlled receiving blades is that the structure is complicated and that the direction of the ocean current and tidal current must be constant for a certain period of time. In addition, it cannot be applied to wave power generation for waves whose flow direction is not constant.

FIG. 12 shows an example in which a large number of turntables are installed in a place near the land where the ocean current and the tidal current are fast. In the figure, the ocean 20 is sandwiched between land 21 and the flow velocity is large. The plurality of turntables 11 are supported by the support structure 2. The support structure 2 is fixed to the land 21 on both sides and is not in a tidal flow and is in a fixed position. The rotating disk rotates and generates electricity under the combined movement of ocean currents, tidal currents and waves.

In order not to obstruct maritime traffic, do not install a turntable near the channel, or lower the support structure to a depth that does not hinder navigation.

The ocean current and tidal current power generation method of the present invention can realize a combined power generation of ocean currents and tidal waves that are large, efficient, and low in cost, use of natural energy in the future, and accompanying reduction of CO2, correction of uneven distribution of energy resources, new economy It can be very effective in creating activities.

DESCRIPTION OF SYMBOLS 1 Anchor 2 Support structure 3 Receiving blade 5 Shaft structure 6 Water surface 7 Seabed 8 Frame 11 Rotating disk 12 Rotating disk 13 Chain 14 Buoy 31 Receiving wing axis 51 Rotor 52 Stator

Claims (2)

A rotating board equipped with multiple passive variable pitch or multiple lift generating fixed pitch or multiple active variable pitch receiving vanes whose surface orientation is vertical, is a bottomed installation or floating body in the horizontal direction near the water surface A marine energy power generation system characterized in that it is tethered and rotated by obtaining a propulsion force in the same direction from the ocean currents and tidal currents that are energy sources, and absorbing energy from this rotation.
2. The ocean energy power generation system according to claim 1, wherein the turntable is installed at a position where the wave motion near the surface of the water is easily received to receive the wave motion along with the ocean current and the tidal current motion.

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