JP6123098B2 - Floating body with vibration reduction function - Google Patents

Description

  The present invention relates to a floating body with a motion reduction function and a floating body with a motion reduction function provided with a power generation system.

  In recent years, floating bodies have been used as marine resource development facilities, leisure facilities, hotels, and the like. There are mono-column hull types and floating spar types. Mono-column hull type floating bodies are attracting attention from both sides of excavation and production of submarine resources because they are less swaying and have a storage capacity compared to ship types and construction costs are low. Further, in a marine structure such as an offshore floating type power generation facility that has been attracting attention in recent years, a spar type floating body may be employed. In such a floating body, large amplitude and long period vortex induced fluctuations (VIM: Vortex Induced Motion) caused by strong tidal currents in the ocean and interference with mooring lines are generated. Easy to do.

  Patent Document 1 discloses a floating body for wave power generation in which a floating body is installed on the sea surface and wave energy is converted into electric power by a generator provided in a contracted portion at the lower part of the floating body. However, this floating body for wave power generation generates a reciprocating water flow in synchronism with ocean waves, and does not actively reduce shaking.

  Patent Document 2 discloses a technique for reducing fluctuations in a floating marine structure in which a disk-shaped lower hull and a cylindrical column are combined by providing fins on the outer peripheral portion of the lower hull. Here, it is also described that fluctuation can be reduced by providing a thruster in the lower hull, rotating the thruster, and controlling the rotation speed and the rotation direction.

  In Patent Document 3, a fluctuation reduction tank is provided in a floating structure, and the water level in the fluctuation reduction tank is adjusted by controlling the rotation of a propeller disposed at the outflow inlet of the fluctuation reduction tank with an electric motor. Thus, a technique for reducing the fluctuation of the floating structure is disclosed.

  In Patent Document 4, a projecting structure portion is provided on the outer periphery of the lower end of the floating structure, and a surrounding wall is further provided around the projecting structure portion. A technique for reducing fluctuations by preventing movement through a gap set at% or less or movement to an adjacent section is disclosed.

Japanese Patent Laid-Open No. 09-144642 Japanese Patent Laid-Open No. 06-56074 JP 09-142380 A JP 2008-74297 A

  In a floating body used in the ocean or the like, it is desired to realize a floating body that can reduce the fluctuation of the floating body and can effectively use natural energy. In addition, it is desired to secure power required for offshore structures and to supply power to nearby facilities by power transmission.

  An object of the present invention is to provide a floating body with a motion reduction function and a floating body with a motion reduction function provided with a power generation system.

The floating body with a motion reduction function according to the present invention includes a floating body, a projecting structure that projects structurally from the floating body, and a relative fluid to the floating body that is attached to the projecting structure via a shaft. A rotating means that can rotate by the flow of the power and a generator that generates electric power by receiving the power of rotation of the shaft, the shaft is provided in a substantially vertical direction with respect to the floating body, and the vortex induced by the floating body reduce the eddy excitation upset. Further, for example, it is preferable that the rotating means can be rotated by a horizontal flow with respect to the floating body.

  Moreover, it is preferable that the said rotation means is provided with the flat rotating blade attached to the said axis | shaft. The rotary blade may have a blade shape or a symmetrical blade shape.

  In addition, it is preferable that the rotating unit includes a plurality of the rotating blades on one of the shafts. At this time, it is more preferable that the plurality of rotor blades are attached to the shaft at different angles when viewed in the axial direction. For example, it is preferable to provide the rotor blades at equiangular intervals with respect to the shaft.

  In addition, it is preferable that the plurality of rotor blades have different sizes along the axial direction. For example, it is preferable that the size of the rotor blades decreases from the upper part toward the lower part along the vertical direction.

  Moreover, it is preferable that the said rotary blade has an end plate in the edge part of the said axial direction.

  Moreover, it is preferable to have a plurality of the rotating means. At this time, it is preferable that the shaft is divided into a plurality of parts in a substantially vertical direction, and the rotating means is provided on each of the divided shafts.

  In addition, it is preferable that a floating body main body overhanging portion is provided at a lower part in the vertical direction of the floating body main body, and the floating body main body overhanging portion also serves as the overhang structure. At this time, it is more preferable that a plurality of the floating body main body overhanging portions are provided at intervals around the floating body main body.

  In addition, it is preferable that load adjusting means for adjusting the load of the generator is provided. It is preferable that the generator includes an inverter unit or a converter unit and a power storage unit connected to each other.

  In addition, it is preferable that the rotating means is driven using the generator as an electric motor to reduce vortex excitation fluctuations caused by vortices induced in the floating body by the flow.

The floating body with a motion reduction function according to the present invention includes a floating body, a projecting structure that projects structurally from the floating body, and a relative fluid to the floating body that is attached to the projecting structure via a shaft. rotating means rotatable by the flow of, including the generator to generate electric power by receiving the motive power of rotation of said shaft, by substantially Rukoto provided in a vertical direction with respect to the floating body the body the shaft, resulting in the floating body VIM (Vortex excitation fluctuation) can be suppressed. That is, by absorbing the fluid flow energy around the floating body by the rotation of the rotating means, VIM generated in the floating body can be effectively reduced. Also, by providing the overhang structure, vortices generated around the floating body can be easily peeled off, and VIM generated in the floating body can be effectively reduced. Further, for example, when the rotating means can be rotated by a horizontal flow with respect to the floating body, the influence of a tidal current or a sea current that is a horizontal flow causing interference of the VIM or the mooring line can be reduced.

  Here, by including a generator that generates power by receiving the rotational power of the shaft, the generator can be used as a rotational load of the rotating means to absorb the energy of the fluid flow around the floating body, The suppression effect of VIM becomes remarkable. Furthermore, the energy of the fluid flow around the floating body can be converted into electric power by the generator, and the energy can be used efficiently.

  In addition, since the rotating means is a plate-like rotating blade attached to the shaft, the fluid flow around the floating body can be absorbed by the rotation of the rotating means by the blade having a simple structure. . Moreover, energy absorption due to rotation of the rotating means can be made more efficient by making the rotary blade into a blade shape or a symmetrical blade shape according to the characteristics of the fluid flow.

  Further, by providing a plurality of the rotating blades on one of the shafts as the rotating means, it is possible to make it possible to absorb energy more effectively according to the state of fluid flow around the floating body. At this time, by attaching a plurality of the rotor blades at different angles when viewed in the axial direction with respect to the shaft, uneven rotation speed depending on the rotation angle during one rotation of the rotating means can be reduced. , VIM suppression effect can be enhanced. In particular, by providing the rotor blades at equiangular intervals with respect to the shaft, it is possible to further reduce unevenness in the rotational speed of the rotating means.

  Further, by varying the size of the plurality of rotor blades along the axial direction, energy absorption can be optimized according to the flow speed along the vertical direction of the floating body. it can. For example, by reducing the size of the rotor blade from the top to the bottom along the vertical direction, the energy of the flow is effectively absorbed in the ocean where the flow of tidal current near the sea surface is often fast. It is possible to increase the VIM suppression effect and improve the power generation efficiency.

  In addition, by providing an end plate at the end in the axial direction on the rotor blade, the generation of vortices generated at the end of the rotor blade can be suppressed, and the efficiency of rotation can be increased.

  Further, by providing a plurality of the rotating means or by dividing the shaft into a plurality of parts in a substantially vertical direction, the shape and size of the rotor blades according to the flow in each peripheral region of the floating body main body. And a load corresponding to the flow can be set.

  Further, a floating body main body overhanging portion is provided at a lower portion in the vertical direction of the floating body main body, and the floating body main body overhanging portion also serves as the overhang structure, thereby dispersing vortices at the end of the overhang structure. Or peeling is accelerated | stimulated and the stability of a floating body can be improved. At this time, for example, by providing a plurality of floating body overhanging portions around the floating body with a space therebetween, the mooring line is exposed to the open space and the load of the mooring line overhanging the floating body is imposed. It can be reduced, the overhang range can be reduced, and the area required for installation of the floating body can be reduced.

  Further, by providing a load adjusting means for adjusting the load of the generator, the load of the rotating means can be adjusted according to the flow around the floating body, and over-rotation of the rotating means is suppressed. it can.

  Further, by using the generator as an electric motor to drive the rotating means, it is possible to reduce vortex excitation fluctuations caused by vortices induced in the floating body by the flow.

It is a perspective view which shows the structure of the floating body in embodiment of this invention. It is a figure which shows the mooring state of the floating body in embodiment of this invention. It is a figure which shows the structure of the electric power control part in embodiment of this invention. It is a perspective view which shows the structure of another example of the floating body in embodiment of this invention. It is a top view which shows the attachment angle of the rotary blade in embodiment of this invention. It is a perspective view which shows the structure of another example of the floating body in embodiment of this invention.

  The floating body 100 in this Embodiment is comprised including the floating body main body 10, the overhang | projection structure 12, the rotation means 14, the generator 16, and the electric power control part 18, as shown in FIG. The floating body 100 is used floating on a fluid such as the ocean. The floating body 100 is used for applications such as marine resource development facilities, leisure facilities, and hotels.

  The floating body 10 has a floating structure having a density lower than that of the fluid to be floated, and is used by being floated in a fluid state. When the floating body 10 is used by floating on water such as the ocean, a floating structure having a density lower than that of water may be provided. The floating body 10 is made of a material having mechanical strength and chemical resistance that can withstand the external environment. Although the floating body 10 is not limited to this, the diameter can be several meters to several hundred meters and the height can be several meters to several hundred meters.

  When the floating body 10 is floated on water such as the ocean, the floating body 10 can be a hollow cylindrical structure formed of a steel plate. Further, by making one end of the cylindrical shape heavier than the other end, the floating body 10 can be kept in a stable posture.

  The overhang structure 12 is a structure portion that projects around the floating body 10. The overhanging structure 12 facing the fluid diffuses the vortex around the floating body 10 generated by the flow of fluid such as tidal current, makes it easy to separate the vortex from the floating body 10, and suppresses the swing of the floating body 10 due to VIM. Has the function of In addition, when the floating body 10 is shaken by waves, it functions as a fluidic resistance and reduces the shake. The overhang structure 12 is preferably provided on at least one of the upper part and the lower part of the floating body 10. Thereby, the overhang | projection structure 12 can be utilized as a support body of the rotation means 14 mentioned later.

  Further, the overhang structure 12 may be provided over the entire circumference of the floating body 10, but it is more preferable to provide a plurality of the protruding structures 12 at intervals around the floating body 10. For example, the overhanging structure 12 is preferably provided by being divided according to the number of rotating means 14 described later. By dividing and providing a plurality of overhanging structures 12, vortex dispersion or separation is promoted at the end of the overhanging structure 12, and the stability of the floating body 100 can be enhanced.

  In addition, as shown in FIG. 2, when a part of the floating body 100 is submerged below the sea surface A and moored to the seabed or the like by the mooring line 200, the mooring line 200 is moved in the seabed direction through the clearance between the overhanging structures 12. Can be extended and installed. Thereby, the burden which projects the mechanism concerning mooring outside is reduced. Moreover, if necessary, the range of the mooring line 200 extending around the floating body 100 can be reduced, the area required for the installation of the floating body 100 can be reduced, and the application range of the floating body 100 can be expanded.

  In addition, it is preferable that at least a part of the overhang structure 12 has a mesh structure. By making the overhang structure 12 a mesh structure, it becomes easy to disperse or peel fine vortices in each mesh, and the stability of the floating body 100 can be further improved.

  The rotating means 14 includes a rotating body installed around the floating body 10. The rotation means 14 may be configured to rotate by the fluid flow around the floating body 10 and to give some load to the rotation. The rotating means 14 is rotated by the fluid flow around the floating body 10 and absorbs flow energy to suppress VIM generated in the floating body 10.

  A plurality of rotation means 14 may be provided. For example, a plurality of sets of rotating means 14 are provided along the periphery of the floating body 10. At this time, it is preferable to arrange the rotation means 14 at a position that is line symmetric or point symmetric around the floating body 10. Thereby, the balance of the floating body 10 can be improved, and VIM generated by the flow around the floating body 10 can be evenly suppressed.

  The rotating means 14 can be configured to include, for example, a shaft 20, an end plate 22, and a rotating blade 24. The shaft 20 becomes the rotation center of the rotation means 14. The shaft 20 is mechanically connected to a generator 16 described later, and transmits the rotational force of the rotating means 14 to the generator 16. An end plate 22 is provided in a direction protruding from the shaft 20, and a rotary blade 24 is provided along the direction of the shaft 20 from the end plate 22. The end plate 22 structurally supports the rotor blade 24, suppresses the generation of vortices generated at the end of the rotor blade 24, and increases the efficiency of rotation. The rotary blade 24 may have any shape as long as a rotational force is applied to the shaft 20 by the fluid flow around the floating body 10, but may be a flat plate, a blade shape, a symmetrical blade shape, or the like.

  The direction of the shaft 20 is not limited to a substantially vertical direction, and the shaft 20 may be set in various directions other than the vertical direction according to the state of fluid flow around the floating body 10. For example, the shaft 20 may be provided in a substantially horizontal direction. However, it is preferably rotatable by a horizontal flow such as a tidal current or a sea current that causes VIM.

  The generator 16 converts the rotation of the rotating means 14 into electric power. The generator 16 functions as a load on the rotating means 14. The generator 16 may be provided for each rotation means 14, or one generator 16 may be provided for the plurality of rotation means 14 via the rotation transmission mechanism, or one generator 16 may be provided for each of the plurality of generators 16. The rotating means 14 may be connected.

  The power control unit 18 receives power from the generator 16 (alternating current) and controls the input power. As shown in the system configuration diagram of FIG. 3, the power control unit 18 includes a rectifier 30, a converter 32, an inverter 34, a floating body power supply 36, a load regulator 38, a load 40, a storage controller 42, a storage battery 44, and a rotation speed detection. And a system controller 48.

  The electric power generated by the generator 16 (alternating current) is input to the rectifier 30. The electric power converted from alternating current to direct current by the rectifier 30 is converted into a voltage by a converter 32 (DC / DC). Part of the DC power output from the converter 32 is converted back to AC by the inverter 34 (DC / AC) and input to the floating body power supply 36. The floating body power supply 36 supplies electric power used in the floating body 100. The power supplied from the floating body power supply 36 is controlled by the system controller 48. A part of the DC power from the converter 32 is input to the storage controller 42 and stored in the storage battery 44. Further, when the power consumed in the floating body 100 cannot be covered by the output power from the converter 32, the power stored in the storage battery 44 is supplied to the inverter 34 via the power storage controller 42 and converted to AC power. After that, the floating body power supply 36 is supplied. Charging / discharging in the storage battery 44 is controlled by the system controller 48. The system controller 48 controls the supply of power from the floating body power supply 36 and the charge / discharge of the storage battery 44 in an integrated manner so that the power generated by the generator 16 is effectively used. When the system controller 48 causes the generator 16 to function as a motor, the system controller 48 controls the power storage controller 42, the load regulator 38, and the generator 16 to operate the motor.

  The power control unit 18 is preferably provided with a load adjuster 38 and a load 40 so that the load on the rotating means 14 can be adjusted. For example, the load 40 is a resistor connected to the rectifier 30, and the load regulator 38 can change the resistance value of the load 40 connected to the rectifier 30. The load regulator 38 is controlled by the system controller 48. By changing the resistance value of the load 40, the consumption amount of the power rectified by the rectifier 30 at the load 40 is changed, and the load of the rotating means 14 can be increased or decreased via the generator 16.

  As described above, by providing the load adjuster 38 and the load 40, it is possible to adjust the rotation load of the rotating unit 14 with respect to the flow around the floating body 100. For example, the system controller 48 adjusts the load 40 in accordance with the flow speed around the floating body 100 and the magnitude of VIM generated in the floating body 100. Specifically, the load 40 may be controlled to increase as the flow speed around the floating body 100 or the VIM generated in the floating body 100 increases. Thereby, generation | occurrence | production of VIM can be suppressed more effectively.

  As described above, by increasing / decreasing the load of the rotating means 14, the swinging of the floating body 100 can be effectively reduced. However, it is possible to adjust the effective power generation amount and to prevent the rotating means 14 and the generator 16 from over-rotating. It becomes.

  It is also preferable to provide the generator 16 with a rotation speed detector 46. The rotational speed detector 46 can detect the flow speed around the floating body 100. Therefore, the system controller 48 may adjust the load 40 according to the rotational speed detected by the rotational speed detector 46. Further, the load 40 may be connected to the rectifier 30 in order to apply a rotational load to the rotating means 14 when the rotational speed detected by the rotational speed detector 46 exceeds a predetermined threshold value.

  In the present embodiment, the load regulator 38 and the load 40 are connected to the rectifier 30, but at least one of the rectifier 30, the converter 32, the inverter 34, and the floating body power supply 36 is provided with a load adjustment means. That's fine. The rectifier 30, the converter 32, and the inverter 34 may be provided as necessary. The generator 16 can also be a DC generator. In addition, since the rotation direction changes also with the change of the flow direction of a tidal current or an ocean current, and arrangement | positioning of the rotation means 14 with respect to the floating body 10, the generator 16 is what can be rotated forward and reverse.

  It is also preferable that the generator 16 is a motor / generator that can also be used as an electric motor, and the rotating means 14 can be forcibly rotated by supplying electric power from the outside or the storage battery 44. By rotating the rotating means 14 in this way, VIM caused by vortices induced in the floating body 10 by the flow can be actively reduced.

  As shown in FIG. 1, it is also preferable to change the size (width) of the rotary blade 24 of the rotating means 14 along the direction of the shaft 20. For example, when the flow speed differs along the vertical direction of the floating body 10, the size of the rotary blade 24 may be set according to the flow speed. Specifically, it is only necessary to increase the load on the rotating means 14 by increasing the rotary blade 24 at a location where the flow is faster. When the floating body 100 is used floating on the ocean, the tidal current and the current flow are often fast near the sea surface. Therefore, the closer to the sea surface, that is, the larger the rotor blades 24 from the bottom to the top along the vertical direction. Is preferred. In addition, when sufficient rotational force can be obtained from tidal currents or ocean currents, the rotor blades 24 can be made smaller or the same from the lower part toward the upper part so as not to over-rotate.

  Further, as shown in FIG. 4, the rotating means 14 may be configured to include a plurality of rotating blades 24 on one of the shafts 20. The plurality of rotor blades 24 may be fixed to the shaft 20, and a power transmission mechanism may be provided between each rotor blade 24 and the shaft 20.

  When the plurality of rotor blades 24 are fixed to the shaft 20, as shown in FIG. 5, it is preferable that the rotor blades 24 are attached to the shaft 20 at different angles as viewed in the axial direction. For example, it is preferable to arrange the plurality of rotor blades 24 so that the angles thereof are equally spaced when viewed in the axial direction. Thereby, the nonuniformity of the rotational speed depending on the rotational angle during one rotation of the rotating means 14 can be reduced, and the VIM suppression effect can be enhanced. In particular, in a situation where the flow changes according to the distance from the floating body 10, unevenness in the rotational speed of the rotating means 14 can be reduced.

  Further, a mechanism for transmitting the rotation of a plurality of independent rotor blades 24 to one shaft 20 may be provided. For example, a ratchet mechanism may be provided between each rotor blade 24 and the shaft 20 so that the shaft 20 rotates in accordance with the rotor blade 24 having the highest rotational speed. Further, the rotational speeds of the plurality of rotor blades 24 may be made to coincide with each other and transmitted to the shaft 20 using a planetary gear or the like. As a result, the rotation of the rotating blade 24 that rotates the fastest among the plurality of rotating blades 24 can be transmitted to the shaft 20, making the absorption of flow energy more effective and increasing the efficiency of power generation by the generator 16. be able to.

  Further, as shown in FIG. 6, the shaft 20 may be divided into a plurality of parts in a substantially vertical direction, and the rotating means 14 may be provided on each of the divided shafts 20. In this case, it is preferable to provide the generator 16 on each shaft 20. By setting it as such a structure, the shape and magnitude | size of the rotary blade 24 can be set according to the flow of the periphery for each area | region of the peripheral part of the floating body 10, and the load 40 can be set. . Therefore, VIM can be more effectively suppressed and power generation efficiency can be increased. In addition, in FIG. 6, although the structure which divided | segmented the axis | shaft 20 into 2 was shown, you may divide | segment into 3 or more.

  As described above, according to the floating body 100 in the present embodiment, VIM of the floating body 100 can be suppressed and natural energy can be used for power generation.

  [Industrial Applicability] The present invention can be used to reduce fluctuation of a floating body and to effectively use natural energy. The present invention is not limited to structures such as marine resource development facilities, leisure facilities, and hotels, and can be applied to all floating bodies that are used by floating on a flowing fluid.

  DESCRIPTION OF SYMBOLS 10 Floating body main body, 12 Overhang structure, 14 Rotating means, 16 Generator, 18 Power control part, 20 Axis, 22 End plate, 24 Rotor blade, 30 Rectifier, 32 Converter, 34 Inverter, 36 Floating body power supply, 38 Load adjustment , 40 load, 42 storage controller, 44 storage battery, 46 revolution detector, 48 system controller, 100 floating body, 200 mooring line.

Claims (13)

A floating body,
An overhang structure structurally overhanging from the floating body, and
Rotating means attached to the projecting structure via a shaft and rotatable by a fluid flow relative to the floating body, and a generator for generating electric power by receiving the power of rotation of the shaft. substantially arranged in the vertical direction, motion suppression function floating body, characterized that you reduce eddy excitation upset by vortex induced in the floating body relative to the floating body the body. The floating body with a sway reduction function according to claim 1 ,
The said rotating means is provided with the flat rotating blade attached to the said axis | shaft, The floating body with a fluctuation reduction function characterized by the above-mentioned. The floating body with a motion reduction function according to claim 2 ,
The rotating means includes a plurality of the rotating blades on one of the shafts, and a floating body with a motion reduction function. It is a floating body with a motion reduction function according to claim 3 ,
The floating body with a motion reduction function, wherein the plurality of rotor blades are attached to the shaft at different angles when viewed in the axial direction. A floating body with a sway reduction function according to claim 3 or 4 ,
The floating body with a motion reduction function, wherein the plurality of rotor blades have different sizes along the axial direction. A motion suppression function floating body according to any one of claims 2-5,
The rotating blade has a fluctuation reducing function, wherein the rotating blade has an end plate at an end in the axial direction. It is a floating body with a rocking | fluctuation reduction function of any one of Claims 1-6 ,
A floating body with a motion reduction function, comprising a plurality of the rotating means. A motion suppression function floating according to any one of claims 1 to 7
The shaft is divided into a plurality of parts in a substantially vertical direction,
A floating body with a motion reduction function, wherein the rotating means is provided on each of the divided shafts. It is a floating body with a rocking | fluctuation reduction function of any one of Claims 1-8 ,
A floating body overhanging portion projecting around the bottom of the floating body in the vertical direction;
The floating body with a motion reduction function, wherein the floating body overhanging portion also serves as the overhanging structure. The floating body with a motion reduction function according to claim 9 ,
A floating body with a motion reduction function, wherein a plurality of the floating body overhanging portions are provided around the floating body at intervals. It is a floating body with a rocking reduction function given in any 1 paragraph of Claims 1-10,
A floating body with an oscillation reduction function, comprising load adjusting means for adjusting a load of the generator. It is a floating body with a rocking | fluctuation reduction function of any one of Claims 1-11 ,
A floating body with a motion reduction function, comprising: inverter means or converter means connected to the generator; and power storage means. It is a floating body with a rocking reduction function given in any 1 paragraph of Claims 1-12 ,
Driving the rotating means using the generator as an electric motor;
A floating body with a motion reduction function, wherein vortex-induced motion due to a vortex induced in the body is reduced by the flow.

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