JP2013256920A - Wave-power generation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wave-power generation device with a turbine rotating in the same one direction by a reciprocating flow of air, capable of maintaining a high degree of conversion efficiency even if its cycle or wind velocity varies, with its structure being of a simple one resulting in a small number of movable parts and components, thus its equipment cost being reduced and maintenance being made easy.SOLUTION: There is provided a wave-power generation device 10 that generates power by a turbine 14 installed in a duct 13 in communication with an air chamber 11 into which sea water W flows in and out, with a turbine 14 to be constituted of a variable pitch turbine 100 so constructed that its blade 120 is brought to rotate autonomously around a mounting angle change shaft 121 without performing an operation input, in response to the direction of the flow of air within the duct 13, air velocity, or rotational angular velocity of the turbine shaft 110.

Description

  The present invention relates to an improvement of a wave power generation apparatus that is used on the coast and generates power using wave energy.

Conventionally, various types of wave power generation devices that generate power using wave energy have been proposed, and a duct through which air enters and exits communicates with an air chamber having an opening through which seawater enters and exits. A wave power generator having a structure in which a turbine that rotates by movement of incoming and outgoing air is provided to drive a generator is known.
In such a wave power generation device, the direction of the air flow in the duct is switched in a short cycle, and the cycle and wind speed are not constant depending on the wave condition. A turbine is used that rotates in the same direction with the flow.
A variable pitch propeller is known as one that maintains efficiency over a wide range of wind speeds, and is widely used in propellers and windmills for propulsion of aircraft and the like.
In particular, variable pitch propellers have been widely used for aircraft propulsion since the 1930s. As a representative example, the Hertzwell method has been the mainstream, but this method uses a mechanical governor and hydraulic pressure. The problem is that it consists of a piston, a cam mechanism, etc., is complicated, takes time to maintain, and is expensive.
Various mechanisms have been proposed to solve this problem.
For example, as shown in Patent Documents 2 and 3, it is known that the rotation axis of the blade is provided in front of the pressure center of the blade, and the mounting angle is autonomously changed by the balance between the aerodynamic force and the reaction force of the spring. is there.
Also, as shown in Patent Document 4, the trailing edge of the blade tip is extended and the blade mounting angle is changed only by aerodynamic force, or as shown in Patent Document 5, an array is attached to the blade tip, It is known that the torsion angle of the propeller blade is autonomously changed using the mass distribution of the array.

U.S. Pat. No. 4,221,538 JP 2007-50869 A JP 2004-353644 A JP-A-6-56092 JP 63-212200 A

However, the turbine described in Patent Document 1 rotates in the same direction by a reciprocating air flow and has a problem that the energy conversion efficiency is as low as about 40% although it is less affected by the cycle and wind speed. Although known variable pitch propellers as described in 2 and 3 can maintain high efficiency over a wide range of wind speeds, the center of gravity of the blade tends to be located behind the rotation axis, and there is a risk of causing flutter, and the rotation of the propeller Due to the moment of inertia accompanying this, a moment for reducing the mounting angle of the blade was added, and it was difficult to always keep the effective angle of attack of the blade at an ideal value.
In addition, since the elasticity of the spring is used, there are many movable parts and a large number of parts, which causes a problem that maintenance is troublesome.
Although the known variable pitch propeller as described in Patent Document 4 has a simple mechanism, the blade plane shape cannot be optimized, so that the propeller efficiency is lowered, and the known variable pitch propeller as described in Patent Documents 2 and 3 is used. Similar to the pitch propeller, there were a flutter problem due to the center of gravity of the blade and a moment of inertia accompanying the rotation of the propeller.
In the known variable pitch propeller as described in Patent Document 5, although the propeller efficiency is improved by changing the torsion, the structure of the blade is complicated and the configuration of changing the mounting angle is disclosed in Patent Documents 2, 3 This is similar to the known variable pitch propeller as described above, and has the same problems.
In addition, since an array having a high air resistance is attached to the tip of the blade that becomes high speed, there is a problem that the air resistance of the blade increases.
And since the well-known variable pitch propellers as described in Patent Document 2 to Patent Document 5 can only deal with the air flow in a certain direction, when the direction of the air flow is switched in a short cycle, the air in the reverse direction The energy of the flow cannot be used, and in order to use this, a plurality of ducts and variable pitch propellers must be made independent so that an air flow in a certain direction is always generated by a device such as a valve. However, there is a problem that the number of movable parts and components of the entire wave power generation apparatus increases and the scale of equipment increases, equipment costs increase, and maintenance frequency also increases.

  The present invention solves a known problem, in which a turbine rotates in the same direction by a reciprocating air flow, and can maintain high conversion efficiency even if its period and wind speed fluctuate. Another object of the present invention is to provide a wave power generation device that has few components, reduces equipment costs, and facilitates maintenance.

  The invention according to claim 1 is an air chamber having an opening through which seawater enters and exits by waves, a duct that communicates with the air chamber and through which air enters and exits, and is rotated by movement of the air that is provided in the duct and enters and exits. And a generator driven by the rotation of the turbine, wherein the turbine is a variable pitch turbine having a turbine shaft in the air flow direction, and the variable pitch turbine is A turbine shaft, a plurality of blades rotating around the turbine shaft, a mounting angle changing shaft integrally provided on the turbine shaft side of the blade, and a state in which the mounting angle changing shaft is rotatable And a hub connected to the turbine shaft, and the blade performs an operation input in accordance with an air flow direction in the duct, an air velocity, and a rotational angular velocity of the turbine shaft. By being configured to rotate in without autonomously the mounting angle change shaft around solves the above problems.

In the invention according to claim 2, in addition to the configuration of the wave power generation device according to claim 1, in the blade, the rotation axis of the mounting angle changing shaft is forward of a quarter of the chord length of the blade. The blade is provided with a counterweight capable of adjusting a fixed position, and a direction in which the moment of inertia around the rotation axis of the counterweight is maximum is the rotation axis of the blade. It is formed so as to be orthogonal to the direction in which the surrounding moment of inertia becomes maximum, and the center of gravity of the blade and the counterweight is configured so as to be located on the rotation axis, thereby solving the problem. Is.
The invention according to claim 3 is characterized in that, in addition to the configuration of the wave power generation device according to claim 2, the counterweight is configured to change the moment of inertia around the rotation axis. It is a solution.
The invention according to claim 4 is configured such that, in addition to the configuration of the wave power generation device according to claim 2 or claim 3, the counterweight can change the position of the center of gravity in a plane orthogonal to the rotation axis. Therefore, the problem is solved.
The invention according to claim 5 includes, in addition to the configuration of the wave power generation device according to claim 3 or claim 4, a base member in which the counterweight is fixed to the blade or the mounting angle changing shaft, and the base member And the base member is configured to change the distance from the rotation axis of the weight main body, thereby solving the problem.
The invention according to claim 6 includes, in addition to the configuration of the wave power generation device according to any one of claims 3 to 5, the base weight fixed to the blade or the mounting angle changing shaft, A weight main body fixed to the base member, and the base member is configured to be able to exchange weight main bodies having different masses, thereby solving the above-mentioned problems.
According to the seventh aspect of the present invention, in addition to the configuration of the wave power generation device according to any one of the first to sixth aspects, the generator is provided in the duct and directly connected to a turbine rotating shaft of the turbine. Therefore, the problem is solved.

  According to the wave power generation device according to the first aspect of the present invention, the turbine is autonomously installed without performing an operation input in accordance with the air flow direction in the duct, the air velocity, and the rotational angular velocity of the turbine shaft. Because it is composed of a variable pitch turbine with blades that rotate around the angle change axis, it can be rotated in the forward and reverse directions by reciprocating air flow, and even if its period and wind speed fluctuate, it can maintain high conversion efficiency, There are few movable parts and components of the entire wave power generation device, and the equipment cost is reduced and maintenance is easy.

According to the second aspect of the present invention, the moment around the rotation axis that reduces the blade mounting angle generated by the moment of inertia accompanying the rotation of the turbine is reduced around the rotation axis generated by the counterweight provided in a fixed manner. Therefore, the blade can autonomously reach the optimum angle of attack only by the aerodynamic force applied to the blade without providing a complicated movable mechanism.
As a result, the variable pitch turbine itself that constitutes the turbine has a simple structure, has a small number of moving parts and parts, facilitates maintenance, and can optimize the blade planar shape to improve efficiency. The center of gravity of the weight is located on the axis of rotation so that flutter does not occur, and the effective angle of attack of the blade is autonomously maintained at an ideal value by eliminating the influence of the moment of inertia accompanying the rotation of the turbine. Is possible.
Furthermore, even during reverse rotation, an optimum angle of attack can be obtained without performing any control, and the efficiency can be improved.
In the configuration according to claim 3, in a normal blade, the main inertial axis is in the chord direction, and the inertial moment in this direction is superior to the inertial moment in the other inertial main axis direction orthogonal thereto. In this case, an undesired moment of reducing the blade mounting angle due to the moment of inertia is generated during rotation. However, according to the configuration of the third aspect, the inertia moment of the turbine is adjusted by adjusting the inertia moment of the counterweight. It is possible to eliminate the influence of the moment around the rotation axis that reduces the angle of attack of the generated blade, and it is possible to obtain optimum efficiency according to the use conditions.
According to the configuration of the fourth aspect of the present invention, even if the moment of inertia of the counterweight is changed according to the use conditions, it is possible to always set the overall gravity center position of the blade and the counterweight on the rotation axis. Therefore, even if the balance around the rotation axis is stable and the angle of attack changes, flutter does not occur, and there is no complicated moving mechanism or biasing mechanism to change or stabilize the angle of attack. Will improve.
According to the configuration of the fifth aspect of the present invention, it is possible to easily change the moment of inertia and the position of the center of gravity of the counterweight, and it is easy to change the shape and characteristics of the turbine and to facilitate maintenance.
According to the configuration of the sixth aspect of the present invention, it is possible to easily change the moment of inertia of the counterweight and the position of the center of gravity, and it is possible to greatly expand the range of change, thereby expanding the range of change of the turbine characteristics. In addition, application to various usage conditions becomes possible.
According to the configuration of the seventh aspect, by omitting the rotational drive system from the turbine in the duct to the generator, there is no loss of the rotational drive system during power generation, and energy conversion efficiency can be further improved. It becomes possible.

BRIEF DESCRIPTION OF THE DRAWINGS Schematic explanatory drawing at the time of forward rotation of the wave power generator which is one Embodiment of this invention. BRIEF DESCRIPTION OF THE DRAWINGS Schematic explanatory drawing at the time of reverse rotation of the wave power generator which is one Embodiment of this invention. Explanatory drawing of the relationship between the angle of attack of a blade of a variable pitch turbine and lift. The schematic operation | movement explanatory drawing of a variable pitch turbine. 1 is a partial cross-sectional external view of a variable pitch turbine that constitutes a turbine of a wave power generator that is an embodiment of the present invention. FIG. 6 is a partial cross-sectional perspective view inside the spinner of FIG. 5. The expansion perspective view of the counterweight of FIG. The diagram which shows the front projection shape of the variable pitch turbine which comprises the turbine of the wave power generator which is one experimental example of this invention. The graph which shows the efficiency of the variable pitch turbine of FIG.

  The wave power generation device of the present invention is rotated by movement of air that is provided in the duct and has an air chamber having an opening through which seawater enters and exits by waves, a duct that communicates with the air chamber, and air enters and exits. And a generator driven by the rotation of the turbine, the turbine comprising a variable pitch turbine having a turbine shaft in the air flow direction, the variable pitch turbine comprising: A turbine shaft, a plurality of blades rotating around the turbine shaft, a mounting angle changing shaft integrally provided on the turbine shaft side of the blade, and a turbine shaft in a state in which the mounting angle changing shaft is rotatable The blade is autonomously mounted without any operation input according to the air flow direction in the duct, the air speed, and the rotational angular speed of the turbine shaft. It is configured to rotate around the further axis, and the turbine rotates in the forward and reverse directions by the reciprocating air flow, so that high conversion efficiency can be maintained even if the cycle and wind speed fluctuate. Any specific embodiment may be used as long as it has a simple structure, few movable parts and components, can reduce equipment costs, and can be easily maintained.

A basic configuration and operation of the wave power generation device of the present invention will be described with reference to FIGS. 1 and 2.
The wave power generation device 10 of the present invention is provided in an air chamber 11 having an opening 12 through which seawater W can enter and exit, a duct 13 communicating with the air chamber 11 and allowing air to enter and exit, and the duct 13. The turbine 14 is rotated by the movement of air entering and exiting (air flow F), and a generator (details will be described later) driven by the rotation of the turbine 14 is installed on the coast or the like.
For example, when the wave power generation device 10 is installed on the coast, the opening 12 is provided so that the upper end thereof does not come out on the sea surface even at low tide. When the seawater W enters the air chamber 11 from the opening 12 and a wave is drawn, the seawater W is discharged from the air chamber 11 as shown in FIG. Is set not to enter or exit.

As the seawater W enters and exits, the air in the air chamber 11 enters and exits from the communicating duct 13, and the direction is switched in the duct 13 in synchronization with the wave period. Is generated.
In the duct 13, a turbine 14 composed of the variable pitch turbine 100 is installed so that the turbine shaft is in the reciprocating direction of the air flow F. The turbine 14 is rotationally driven by the air flow F in the duct 13. The
In the present embodiment, the turbine 14 is provided with a generator 102 (details will be described later) coaxially with the turbine shaft, and the electric power generated by the generator 102 is passed through a transformer 15 provided appropriately outside. Power is transmitted.

Next, the basic operation of the variable pitch turbine constituting the turbine of the wave power generator of the present invention will be described.
The variable pitch turbine constituting the turbine of the wave power generation device of the present invention uses the fact that the point of action of the lift acting on the blade changes its position in the chord length direction according to the angle of attack, thereby changing the blade mounting angle The position of the axis of rotation of the shaft is stabilized by positioning it at the point of action of the lift at a predetermined angle of attack, and by adding a counterweight, the moment of inertia accompanying the rotation of the turbine is changed, and the change in the rotational speed It makes the change in the angle of attack due to the optimum.

FIG. 3 shows the relationship between the angle of attack and lift when the chord length is c and the moment coefficient (Cm) is a Reynolds number of 200,000 for a positive blade.
For example, if the position of the rotational axis of this blade is the position where lift acts when the angle of attack is 5 °, and the weight balance between the front and rear is taken, the moment around the rotational axis resulting from the lift will be less than 5 °. In this case, the angle of attack increases toward the angle of attack, and when the angle of attack exceeds 5 °, the angle of attack decreases. Therefore, when only lift is considered, the angle of attack is autonomously stabilized at 5 °.
This lift is proportional to the square of the airspeed U in the blade chord direction.
In addition, when the twist of the blade in the longitudinal direction is taken into consideration, the blade is autonomously stabilized at an angle of attack at which the sum of moments about the rotation axis in all cross sections in the longitudinal direction becomes zero.

The variable pitch turbine constituting the turbine of the wave power generator of the present invention removes the moment to reduce the mounting angle due to the rotation of the turbine and the moment of inertia by adding a counterweight, and the air applied to the blades The angle of attack of the blade is autonomously and optimally stabilized according to the rotational speed of the turbine only by the force.
FIG. 4 schematically shows blade cross sections and counterweights having radii of 0.4R, 0.6R, and 0.8R.
The blade of the variable pitch turbine that constitutes the turbine of the wave power generation device of the present invention is a blade type having a positive moment coefficient (Cm), and has a chord length from the blade leading edge using a constant k of 0.25 or less. The rotation axis CP of the mounting angle changing shaft is placed at a position of k times.
Of the principal axes of inertia perpendicular to the rotation axis CP, the axis with the larger moment of inertia is the y-axis, the axis with the smaller moment is the z-axis, and the moments of inertia are denoted as Iyy and Izz.
Generally, the y-axis is in the direction connecting the leading edge and the trailing edge of the blade.
In addition, a counterweight that is vertically symmetrical is provided in the z-axis direction of the root of the blade on the turbine shaft side, and the distance from the rotation axis CP of the center of gravity of each of the upper and lower sides is 1 and the mass is m.
The distance l and the mass m of the counterweight center of gravity from the rotation axis CP are variable, and the center of gravity position around the rotation axis CP of the blade and the entire counterweight is added to the rotation axis CP by adding a separate mass (not shown). Match.

Iyy, Izz of the entire rotating body of the blade and the counterweight is Iyy ′, Izz ′ and the inertia moment of the counterweight is Iyy ″, Izz ″,
Iyy = Iyy '+ Iyy "
Izz = Izz ′ + Izz ”
And
The moment of inertia Izz "of the counterweight in the z-axis direction is
Izz ”= 2 ml ²
Given in.
The inertia moments Iyy 'and Izz' of the blade itself are constant, and the inertia moment Iyy "of the counterweight in the y-axis direction is small in the front and rear lengths in this model. The moment of inertia Iyy is substantially constant.
The moment of inertia Izz in the z-axis direction of the entire rotating body can be adjusted by changing Izz ″ by changing the distance l or the mass m of the center of gravity of the counterweight from the rotation axis CP.

When the above blade is rotated around the turbine axis, the following moment Mi is generated around the x-axis (which coincides with the rotation axis CP in this description) extending through the center of gravity of the blade in a direction orthogonal to the turbine axis. Is generally known.
Mi = −1 / 2Ω ² (Iyy−Izz) sin 2θ
Here, Ω is the rotation angular velocity, and θ is the y-axis inclination from the rotation surface. Note that Mi is positive in the direction in which the mounting angle increases.
The moment Mi increases as the difference between the values of Iyy and Izz increases, and the moment Mi becomes maximum when θ is 45 °, and is proportional to the square of the rotational angular velocity Ω.

The shape of the blade is designed so that the efficiency of the turbine is optimized assuming a predetermined angle of attack under a predetermined condition (a relationship between the air velocity U and the rotational angular velocity Ω in a predetermined blade chord direction). When the predetermined condition changes, the y-axis inclination θ that is autonomously stable when the angle of attack of the blade changes due to the aerodynamic moment is affected by the Mi due to the inertial moment. There is a problem that the turbine efficiency is lowered from the optimum value.
In the present invention, a counterweight capable of arbitrarily setting the above Izz ″ is fixed so that the turbine efficiency is optimized even when the relationship between the air velocity U and the rotational angular velocity Ω in the blade chord direction is changed. is there.
That is, a counterweight formed so that the direction of maximum moment of inertia around the rotation axis is different from the direction of maximum moment of inertia around the rotation axis of the blade can be fixed to the blade, and the position and weight of the counterweight can be fixed. By adjusting Iy = Izz (Mi = 0), when the angle of attack of the blade changes autonomously by aerodynamic force, the influence of Mi that changes according to the above equation is eliminated, and the mounting angle changing shaft Without providing any additional movable mechanism other than the rotating mechanism, the blade can be autonomously set to the optimum angle of attack, and the turbine efficiency can be maintained optimally.
Also, even for airflow in the direction opposite to that described above with respect to the turbine shaft, the blade simply changes the angle by 180 ° and geometrically has the same shape, so the same efficiency is exhibited regardless of the direction of airflow. To do.

Next, a variable pitch turbine 100 constituting the turbine 14 of the wave power generation device 10 according to one embodiment of the present invention will be described with reference to FIGS.
As shown in FIG. 5, in the variable pitch turbine 100 constituting the turbine 14 of the wave power generation device 10 according to the present embodiment, the rotating shaft of the generator 102 is directly the turbine shaft 110 and is fixed to the turbine shaft 110. The mounting angle changing shaft 121 of the blade 120 is rotatably attached to the hub 140 formed.
The generator 102 is fixed to the generator mount 101 so that the turbine shaft 110 protrudes, and the generator housing 103 is fixed to the generator mount 101 so as to cover the outer periphery of the generator 102. A housing base 104 is fixed to the housing 103 so as to accommodate the generator 102.

The hub 140 is provided with a bearing 143, the mounting angle changing shaft 121 of the blade 120 is inserted into the inner periphery of the bearing 143, and the nut 144 is screwed to the end portion of the mounting angle changing shaft 121, whereby the blade 120. Is attached to the hub 140 so that only the rotation of the attachment angle changing shaft 121 around the rotation axis is possible.
In the drawing, the bearing 143 is constituted by two rows of ball bearings of thrust and radial.
A counterweight 130 is fixed to the mounting angle changing shaft 121 in the vicinity of the hub 140.

  As shown in FIGS. 3 and 4, the periphery of the hub 140 and the counterweight 130 is covered with a spinner 142 that rotates integrally with the turbine shaft 110 and the hub 140.

Also, left and right of the spinner 142 are provided with mounting angle changing shaft insertion holes 145 into which the mounting angle changing shaft 121 of the blade 120 can be inserted.
Note that the variable pitch turbine 100 constituting the turbine 14 of the wave power generation device 10 according to the present embodiment has two blades 120 arranged at a position 180 ° in the rotational direction with respect to the turbine shaft 110. 140 and the spinner 142 are 180 ° rotationally symmetric shapes and structures with respect to the axis of the turbine shaft 110, but when the number of blades 120 is three, four, etc., the shape of the hub 140 and the spinner 142, The structure may also have a shape and structure such as 120 ° rotational symmetry and 90 ° rotational symmetry.

As shown in FIG. 7, the counterweight 130 includes a plurality of weight main bodies 131 having fixed pieces 132 and a base member 134 having arm portions 139 extending in three directions capable of fixing the fixed pieces 132.
The base member 134 is provided with a blade fixing hole 137 into which the mounting angle changing shaft 121 of the blade 120 is inserted. The blade fixing screw has a thread formed on the inner peripheral surface thereof penetrating into the blade fixing hole 137 from the side. A hole 138 is provided.
The base member 134 is firmly attached to the mounting angle changing shaft 121 by inserting the mounting angle changing shaft 121 into the blade fixing hole 137 and screwing and fixing a blade fixing screw (not shown) into the blade fixing screw hole 138. It is fixed and rotates around the turbine axis together with the blade 110 and rotates around the rotation axis.

A fixing elongated hole 133 is provided in the fixing piece 132 of the weight main body 131, and two weight fixing screw holes 135 for fixing the fixing piece 132 are respectively provided in the arm portions 139 extending in three directions of the base member 134. Is provided.
The arm portion 139 and the fixing piece 132 are firmly fixed by inserting the weight fixing screw 136 through the fixing elongated hole 133 of the fixing piece 132 and tightening the weight fixing screw 136 to the weight fixing screw hole 135, whereby the base member 134 and the weight main body are fixed. Reference numeral 131 forms a counterweight 130 together.

The two weight fixing screw holes 135 of each arm portion 139 are provided side by side in a direction away from the rotation axis of the mounting angle changing shaft 121, and the fixing elongated hole 133 of the fixing piece 132 is formed by the two weight fixing screws. It is set longer than the interval between the holes 135.
Thus, the distance from the rotation axis of the mounting angle changing shaft 121 of the weight main body 131 can be adjusted and fixed, and the moment of inertia around the rotation axis can be adjusted.
Further, the weight main body 131 can be replaced by completely removing the weight fixing screw 136, and the inertia moment around the rotation axis can be adjusted by fixing the weight main body 131 having a different mass.

Of the arm portions 139 extending in three directions, two are configured to extend in a 180 ° symmetrical direction within a plane orthogonal to the rotation axis of the mounting angle changing shaft 121, and the other one is configured to extend in a 90 ° direction. When the base member 134 is fixed to the mounting angle changing shaft 121, the former two arm portions 139 are set to be in a direction orthogonal to the direction in which the moment of inertia around the rotation axis of the blade 120 is maximized.
Thus, the weight body 131 attached to the former two arm portions 139 adjusts the moment around the rotation axis that reduces the attachment angle of the blade 120 generated by the moment of inertia accompanying the rotation of the turbine. The weight body 131 attached to the latter arm portion 139 extending in the 90 ° direction can optimally maintain the position of the center of gravity around the rotation axis of the entire blade 120. Become.
In the present embodiment, the shape and dimensions of the three arm portions 139 and the shape and dimensions of the weight main body 131 attached to each of the arms 139 are the same. However, different shapes and dimensions may be used.
Further, the shape, structure, and dimensions of each part are not limited to those shown in the drawings.

Next, an experimental example of a variable pitch turbine constituting the turbine of the wave power generation device of the present invention will be described.
The blades of the turbine used in the experiment were designed in the front projection shape as shown in FIG. 8 by using the following specifications as design points and using a known design method and performance estimation method.
Airspeed (U) 13.9m / s (100km / h)
Diameter (D) 0.2667m (10.5inch)
Angular velocity (rotation speed n) 1043 rad / s (10,000 rpm)
Output power 225W (0.3hp)
Conversion efficiency 80%

When this turbine is used as a fixed pitch turbine, as shown in FIG. 9, the conversion efficiency decreases immediately when the turbine deviates from the design point.
On the other hand, by using this turbine as a variable pitch turbine that constitutes the turbine of the wave power generation device of the present invention, high conversion efficiency can be realized in a wide range of peripheral speed ratios.
As described above, the variable pitch turbine constituting the turbine of the wave power generation device of the present invention has a circumferential speed ratio, that is, even under use conditions in which the relationship between the airspeed and the rotational angular velocity described above varies widely. High efficiency can be maintained.

  The variable pitch turbine constituting the turbine of the wave power generation device of the present invention can maintain high efficiency even if the peripheral speed ratio varies widely, has a simple structure and has a small number of moving parts and parts, and maintenance. Therefore, it is also suitable for other uses such as wind power generation.

DESCRIPTION OF SYMBOLS 10 ... Wave power generator 11 ... Air chamber 12 ... Opening part 13 ... Duct 14 ... Turbine 15 ... Substation 100 ... Variable pitch turbine 101 ... Generator mount DESCRIPTION OF SYMBOLS 102 ... Generator 103 ... Generator housing 104 ... Housing base 110 ... Turbine shaft 120 ... Blade 121 ... Mounting angle change shaft 130 ... Counterweight 131 ... Weight main body 132 ... Fixing piece 133 ... Fixing long hole 134 ... Base member 135 ... Weight fixing screw hole 136 ... Weight fixing screw 137 ... Blade fixing hole 138 ... Blade fixing screw hole 139 ... arm part 140 ... hub 142 ... spinner 143 ... bearing 144 ... nut 145 ... mounting angle Change shaft insertion hole W ・ ・ ・ Seawater F ・ ・ ・ Air flow

Claims (7)

An air chamber having an opening through which seawater enters and exits by waves; a duct communicating with the air chamber through which air enters and exits; a turbine that is provided in the duct and that is rotated by movement of the air that enters and exits; and the rotation of the turbine A wave power generator having a driven generator,
The turbine comprises a variable pitch turbine having a turbine axis in the direction of air flow;
The variable pitch turbine includes a turbine shaft, a plurality of blades rotating around the turbine shaft, a mounting angle changing shaft integrally provided on the turbine shaft side of the blade, and the mounting angle changing shaft. A hub connected to the turbine shaft in a rotatable state;
The blade is configured to autonomously rotate around the mounting angle changing shaft without performing operation input according to the direction of air flow in the duct, the air speed, and the rotational angular speed of the turbine shaft. A wave power generation device characterized by comprising: The blade is formed in an airfoil in which the rotation axis of the mounting angle changing shaft is positioned in front of a quarter of the blade chord length of the blade,
The blade is provided with a counterweight capable of adjusting a fixed position,
A direction in which the moment of inertia around the rotation axis of the counterweight is maximized is perpendicular to a direction in which the moment of inertia around the rotation axis of the blade is maximized,
2. The wave power generation device according to claim 1, wherein the center of gravity of the blade and the counterweight is configured to be positioned on the rotation axis.   The wave power generator according to claim 2, wherein the counterweight is configured to be able to change a moment of inertia around the rotation axis.   The wave power generator according to claim 3, wherein the counterweight is configured to be able to change a position of a center of gravity in a plane orthogonal to the rotation axis. The counterweight has a base member fixed to the blade or the mounting angle changing shaft, and a weight body fixed to the base member;
5. The wave power generation device according to claim 3, wherein the base member is configured to be capable of changing a distance from a rotation axis of the weight main body. The counterweight has a base member fixed to the blade or the mounting angle changing shaft, and a weight body fixed to the base member;
The wave power generator according to any one of claims 3 to 5, wherein the base member is configured to be able to exchange weight bodies having different masses.   The wave power generator according to any one of claims 1 to 6, wherein the generator is provided in the duct and directly connected to a turbine rotating shaft of the turbine.

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