Variable-Pitch Propeller with Toroidal Blades and Tidal Current Power Generator Employing the Same

Abstract

The present invention relates to a variable pitch propeller having toroidal blades and a tidal power generator using the same, and more specifically, to a variable pitch propeller having toroidal blades configured to vary the pitch of each blade with respect to toroidal blades forming an annular closed-loop structure, and a tidal power generator using the same. The present invention may include a hub, a plurality of toroidal blades radially arranged around the circumference of the hub and forming an annular closed-loop structure, and a pitch control unit configured to vary the pitch while maintaining the closed-loop structure of the toroidal blades.

Description

Technology Field

[0001] The present invention relates to a variable pitch propeller having toroidal blades and a tidal power generator using the same, and more specifically, to a variable pitch propeller having toroidal blades configured to vary the pitch of each blade with respect to a toroidal blade forming an annular closed-loop structure having a pair of roots with respect to a hub, and a tidal power generator using the same. Background Technology

[0003] A standard Controllable Pitch Propeller (CPP) is a technology that improves propulsion efficiency and maneuverability by forming a pitch rotation axis at the root of each blade coupled to a hub and changing the pitch angle of the blades using a hydraulic drive unit inside the hub.

[0004] Meanwhile, recently, toroidal propellers with blades forming a closed loop shape have been proposed to reduce vortices generated at the blade tips and to improve propulsion efficiency and noise characteristics.

[0005] These toroidal propellers have the advantage of reducing tip vortices because there are no free ends of the blades.

[0006] However, most conventional toroidal propellers are designed with a fixed-pitch structure, making it difficult to actively respond to changes in operating conditions, and they had limitations in terms of low-speed maneuverability and reverse thrust operation.

[0007] Furthermore, since the existing CPP structure is designed based on open blades, there are structural and mechanical constraints that prevent its direct application to closed-loop toroidal blades.

[0008] In particular, toroidal blades have different mass and fluid load characteristics compared to general blades due to their loop structure, leading to design challenges such as increased pitch driving torque, root sealing issues, and structural interference.

[0009] Meanwhile, tidal power generation is a marine renewable energy technology that extracts energy from the flow of seawater caused by tides, and it has the advantage of enabling predictable power generation without being significantly affected by weather conditions.

[0010] However, conventional propeller-type tidal generators generate strong vortices in the tip area when the blades rotate, causing underwater noise. This noise overlaps with the echolocation signal band of marine mammals, which can have a problem affecting the marine ecosystem. Prior art literature

[0012] Republic of Korea Registered Patent No. 10-2003499 (Registered July 18, 2019) Republic of Korea Registered Patent No. 10-1358119 (Registered January 27, 2014) The problem to be solved

[0013] The present invention has been devised to solve the problems of the prior art as described above. The objective of the present invention is to provide a variable-pitch propeller having toroidal blades capable of varying the pitch of each blade with respect to toroidal blades forming an annular closed-loop structure having a pair of roots with respect to a hub, and a tidal power generator using the same. means of solving the problem

[0015] A variable pitch propeller having toroidal blades according to the present invention for achieving the above objectives may include a hub, a plurality of toroidal blades radially arranged around the circumference of the hub and forming an annular closed-loop structure, and a pitch control unit configured to vary the pitch while maintaining the closed-loop structure of the toroidal blades.

[0016] In addition, the toroidal blade has a pair of roots spaced apart from each other in the circumferential and axial directions of the hub, and the pitch control unit can cause the pair of roots to rotate synchronously in the same rotational direction and the same rotational angle.

[0017] In addition, the toroidal blade has a pair of roots spaced apart from each other in the circumferential and axial directions of the hub, and each root is provided with a rotating plate installed so as to be rotatable with the hub radius direction toward the center of the hub as the centerline at the position where it is placed, and a coupling shaft linked to the pitch adjustment unit may be formed on the rotating plate.

[0018] In addition, the pitch adjustment unit may include a pair of rack gears meshing with the coupling shafts of each route, and a power transmission gear unit that receives the rotational force of a drive motor and drives the pair of rack gears so that each coupling shaft rotates synchronously at the same angle in the same rotational direction.

[0019] Meanwhile, the tidal power generator according to the present invention may include a support structure fixedly installed on the seabed, a turbine installed on the top of the support structure with a drive shaft, a speed increaser, and a generator installed inside, and a variable pitch propeller having a toroidal blade connected to the drive shaft.

[0020] In addition, it may further include a hydrophone that monitors the underwater noise level in real time, and the pitch control unit may be controlled based on the noise signal measured from the hydrophone. Effects of the invention

[0022] According to the present invention, by configuring each root of a toroidal blade having a pair of roots to rotate synchronously in the same direction of rotation at the same angle and angular velocity by a common dynamometer, an excellent effect is achieved in that the pitch of the entire blade can be varied uniformly while maintaining the closed-loop shape of the toroidal blade.

[0023] In addition, the present invention enables stable pitch control without twisting or local deformation of the blade and has the effect of improving structural reliability.

[0024] In addition, the present invention has the effect of enabling accurate synchronous control even in drive systems having different arrangement angles by driving rack gears that are not arranged parallel to each other due to the arrangement of each route through a multi-stage gear train structure including bevel gears.

[0025] In addition, the present invention enables rapid and precise pitch control in response to changes in current, and has the effect of reducing vortex loss and securing structural rigidity through a toroidal closed-loop shape, thereby improving power generation efficiency. Brief explanation of the drawing

[0027] FIG. 1 is a drawing illustrating a propeller equipped with a conventional toroidal blade. FIG. 2 is a conceptual diagram of a variable pitch propeller having a toroidal blade according to the present invention. FIG. 3 is a conceptual drawing illustrating a pitch control section of a variable pitch propeller having a toroidal blade according to the present invention. FIG. 4 is a conceptual drawing illustrating a pitch control section of a variable pitch propeller as another embodiment having a toroidal blade according to the present invention. FIG. 5 is a conceptual drawing illustrating a pitch control section of a variable pitch propeller as another embodiment having a toroidal blade according to the present invention. FIG. 6 is a conceptual diagram of a tidal power generator using a variable pitch propeller having a toroidal blade according to the present invention. FIG. 7 is a control configuration diagram of a tidal power generator using a variable pitch propeller having a toroidal blade according to the present invention. Specific details for implementing the invention

[0028] The embodiments of the present disclosure are illustrative for the purpose of explaining the technical concept of the present disclosure. The scope of rights according to the present disclosure is not limited to the embodiments presented below or the specific description thereof.

[0029] All technical and scientific terms used in this disclosure, unless otherwise defined, have the meaning generally understood by those skilled in the art to which this disclosure pertains. All terms used in this disclosure are selected for the purpose of further clarifying this disclosure and are not selected to limit the scope of the rights under this disclosure.

[0030] Expressions such as “comprising,” “comprising,” “having,” etc. used in this disclosure should be understood as open-ended terms implying the possibility of including other embodiments, unless otherwise stated in the phrase or sentence containing such expressions.

[0031] Unless otherwise stated, singular expressions described in this disclosure may include a plural meaning, and this applies likewise to singular expressions described in the claims.

[0032] Hereinafter, preferred embodiments of a variable pitch propeller having a toroidal blade according to the present invention and a tidal power generator using the same will be described in detail with reference to the attached drawings.

[0034] The present invention relates to a variable pitch propeller (100, hereinafter referred to as 'propeller') having toroidal blades configured to vary the pitch of each blade with respect to a toroidal blade forming an annular closed-loop structure having a pair of roots with respect to a hub, and a tidal power generator (1000) using the same.

[0035] First, referring to FIG. 2, the propeller (100) of the present invention includes a hub (110) and a plurality of toroidal blades (120) that are radially arranged around the hub (110) and form an annular closed-loop structure.

[0036] The toroidal blade (120) has a pair of roots (122) spaced apart from each other in the circumferential and axial directions of the hub (110), and each root (122) has a rotating plate (124) installed so as to be rotatable with the hub radius direction toward the hub center at the position where it is placed as the centerline.

[0037] A through hole (112) is formed in the hub (110) so that a rotating plate (124) is rotatably inserted and supported therein, and at the same time, a receiving space is formed inside the hub (110) in which a pitch adjustment part (130), to be described later, can be disposed.

[0038] Referring to FIG. 3, the propeller (100) of the present invention may include a pitch control unit (130) configured to vary the pitch while maintaining the closed-loop structure of the toroidal blade (120).

[0039] At this time, a coupling shaft (125) may be formed on the rotating plate (124) to be coupled with the pitch adjustment part (130).

[0040] Additionally, the pitch adjustment unit (130) may include a pair of rack gears (132) that each mesh with a coupling shaft (125) of a rotating plate (124) provided at each root (122) of the toroidal blade (120), and a power transmission gear unit (134) that receives rotational force from a drive motor (136) and drives the pair of rack gears (132) so that each coupling shaft (125) rotates in the same rotational direction at the same angle and the same angular velocity.

[0041] Here, "same direction of rotation" means synchronous rotation with respect to the centerline of rotation of each root, that is, in either a clockwise or counterclockwise direction.

[0042] Accordingly, the toroidal blade (120) maintains a closed-loop shape while the pitch of the entire blade changes simultaneously.

[0043] Meanwhile, depending on the arrangement of each route (122), the connecting shaft (125) is spaced apart in the axial direction of the hub (110) while forming a predetermined angle in the circumferential direction of the hub (110).

[0044] Accordingly, a pair of rack gears (132) engaged with each connecting shaft (125) are not parallel to each other and are angled in the circumferential direction of the hub (110).

[0045] Accordingly, the power transmission gear unit (134) may be formed as a multi-stage gear train structure including a bevel gear to stably transmit the rotational force of the drive motor (136) to a rack gear (132) that has a different angle of arrangement in the circumferential direction of the hub (110).

[0046] With the above configuration, when the drive motor (136) is operated, the rotational force is transmitted to a pair of rack gears (132) through the power transmission gear unit (134), and the rack gears (132) move linearly with the same displacement while mechanically linked to each other.

[0047] The linear movement of the above rack gear (132) rotates the coupling shaft (125) engaged with each, and the rotating plate (124), i.e., the root (122), formed integrally with the coupling shaft (125), rotates at the same angle and same angular velocity at their respective positions.

[0048] With the configuration of the pitch control unit (130) as described above, each route (122) is mechanically coupled by a common dynamometer and synchronously controlled, so that the phenomenon of only one route leading or lagging does not occur structurally.

[0049] Accordingly, the toroidal blade (120) changes the pitch of the entire blade uniformly without twisting or local deformation, and stable pitch control is achieved.

[0050] In addition, since the power transmission gear unit (134), rack gear (132), and coupling shaft (125) are closedly connected as a single power system, even if a slight reverse rotation or deviation occurs in one side of the route due to an external force, the opposite side of the route rotates in tandem, thereby preventing deformation.

[0051] At this time, the rotation angle and rotation speed of each route are determined by the gear ratio between the power transmission gear unit (134), the rack gear (132), and the coupling shaft (125), and through this, the pitch adjustment range, response speed, and driving torque characteristics can be set to suit the design conditions.

[0052] Referring to FIG. 4, toroidal blades (120) are arranged to face each other around the rotation axis of the hub (110), and each toroidal blade (120) includes a pair of roots (122) spaced apart from each other in the circumferential and axial directions of the hub, and each root (122) can be rotatably installed through a rotating plate (124) and a connecting shaft (125).

[0053] Each drive motor (136) is positioned corresponding to a pair of roots (122) positioned on each of the above toroidal blades (120), and the drive motors (136) are synchronously controlled by a control unit (not shown) so that the toroidal blades (120) facing each other can rotate in the same rotational direction and the same rotational angle.

[0054] Referring to FIG. 5, the propeller (100) of the present invention can synchronously drive a plurality of roots (122) by a single drive motor (136).

[0055] The above drive motor (136) includes an output shaft extending in the vertical direction, and a power transmission gear unit (134) coupled to each output shaft is connected to a corresponding rack gear (132) and a coupling shaft (125), so that the roots (122) of the toroidal blades (120) facing each other rotate synchronously in the same rotational direction.

[0056] In the above-described embodiment, a bearing may be provided to support the output shaft of the drive motor (136) so that it rotates stably.

[0058] Referring to FIG. 6, a tidal power generator (1000) using a variable pitch propeller (100) having a toroidal blade according to the present invention may include a support structure (200) fixedly installed on the seabed, a power generation unit (300) installed on the top of the support structure (200) and having a drive shaft, a speed increaser, and a generator installed inside, and a variable pitch propeller (100) having a toroidal blade connected to the drive shaft of the power generation unit (300).

[0059] At this time, the tidal generator (1000) further includes a tidal detection sensor (400) that detects tidal currents.

[0060] Accordingly, the pitch control unit (130) of the propeller (100) is controlled according to the current conditions detected by the current detection sensor (400), so that the pitch of each toroidal blade (120) is actively controlled, and vortex loss is reduced and structural rigidity is secured by the toroidal closed-loop shape, thereby enabling high-efficiency power generation.

[0061] Meanwhile, referring to FIG. 7, the tidal power generator (1000) of the present invention may include an underwater hydrophone (500) that monitors the underwater noise level in real time.

[0062] The above pitch control unit (130) can control the pitch of the toroidal blade (120) to decrease when the noise measured by the underwater hydrophone (500) exceeds a set limit value, thereby reducing the thrust and rotational torque transmitted from the fluid.

[0063] Accordingly, the rotational speed of the hub (110) is gradually reduced, and underwater radiated noise caused by the interaction between the toroidal blade (120) and the fluid is reduced.

[0064] At this time, the pitch control unit (130) may be configured to control the amount of pitch reduction in stages according to the degree of noise excess, thereby enabling stable reduction of rotational speed while preventing structural shock caused by sudden torque changes.

[0065] In addition, the tidal generator (1000) of the present invention may further include an ultrasonic fish detection sensor (600) for detecting the approach of large marine organisms.

[0066] When a large marine organism is detected within a set distance by the ultrasonic fish detection sensor (600), the pitch control unit (130) primarily switches the toroidal blade (120) to a low torque state to rapidly reduce the rotational force.

[0067] Along with this, or thereafter, as needed, the electric braking of the generator (300) can be activated to increase rotational resistance, or the mechanical brake can be driven to temporarily stop the rotation of the hub (110).

[0068] Through the stepwise control described above, a first deceleration stage that minimizes fluid energy absorption and a second stopping stage through electric or mechanical braking can be performed sequentially, thereby effectively reducing the risk of collision with marine organisms.

[0069] Additionally, the above-mentioned underwater hydrophone (500), ultrasonic fish detection sensor (600), and pitch control unit (130) can be integrated and managed by a control module (700), and can be configured to selectively perform a deceleration or stop mode by comprehensively considering the operating conditions, current speed, and power generation load status.

[0070] Accordingly, the present invention provides an eco-friendly tidal power generation system that is not limited to a simple power generation device but can actively implement underwater noise reduction and marine life protection functions.

[0072] Accordingly, according to the variable pitch propeller (100) having a toroidal blade and the tidal power generator (1000) using the variable pitch propeller having a toroidal blade as described above, by configuring each root of a toroidal blade having a pair of roots to rotate synchronously in the same direction of rotation at the same angle and the same angular velocity by a common dynamometer, the pitch of the entire blade can be varied uniformly while maintaining the closed-loop shape of the toroidal blade, as well as stable pitch control without twisting or local deformation of the blade, and structural reliability is improved. Furthermore, by driving the rack gears, which are arranged not parallel to each other due to the arrangement of each root, through a multi-stage gear train structure including a bevel gear, accurate synchronous control can be achieved even in a drive system with different arrangement angles, rapid and precise pitch adjustment according to changes in tidal current is possible, and various advantages such as reduced vortex loss and improved power generation efficiency are achieved by the toroidal closed-loop shape.

[0074] The above-described embodiments are explained with respect to the most preferred examples of the present invention, but are not limited to the above embodiments, and it is obvious to those skilled in the art that various modifications are possible within the scope of the technical spirit of the present invention. Explanation of the symbols

[0076] 100: Variable pitch propeller with toroidal blades 110: Hub 112: Penetrating hole 120: Toroidal Blade 122: Root 124: Turntable 125: Connecting shaft 130: Pitch control section 132: Rack gear 134: Power transmission gear section 136: Drive motor 200: Support structure 300: Power Generation Department 400: Bird detection sensor 500: Hydrophone 600: Ultrasonic fish detection sensor 700: Control Module 1000: Tidal power generator

Claims

Claim 1 A variable pitch propeller having toroidal blades, comprising a hub, a plurality of toroidal blades arranged radially around the hub and forming an annular closed-loop structure, and a pitch control unit configured to vary the pitch while maintaining the closed-loop structure of the toroidal blades. Claim 2 A variable pitch propeller having a toroidal blade, wherein the toroidal blade has a pair of roots spaced apart from each other in the circumferential and axial directions of the hub, and the pitch control unit causes the pair of roots to rotate synchronously in the same rotational direction and the same rotational angle. Claim 3 A variable pitch propeller having a toroidal blade, wherein the toroidal blade has a pair of roots spaced apart from each other in the circumferential and axial directions of the hub, and each root is provided with a rotating plate installed so as to be rotatable with the hub radius direction toward the hub center as the centerline at the position where it is arranged, and a coupling shaft formed on the rotating plate that is linked to the pitch adjustment unit. Claim 4 A variable pitch propeller having toroidal blades, wherein the pitch adjustment unit comprises a pair of rack gears meshing with the coupling shafts of each route, and a power transmission gear unit that receives rotational force from a drive motor and drives the pair of rack gears so that each coupling shaft rotates synchronously at the same angle in the same rotational direction. Claim 5 A tidal power generator comprising a support structure fixedly installed on the seabed, a power generation unit installed on the top of the support structure and having a drive shaft, a speed increaser, and a generator installed inside, and a variable pitch propeller having a toroidal blade according to any one of claims 1 to 4 connected to the power generation unit. Claim 6 A tidal power generator according to claim 5, further comprising a hydrophone that monitors underwater noise levels in real time, and controlling the pitch control unit based on a noise signal measured from the hydrophone.

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