The present disclosure relates generally to hydroelectric energy systems and methods, and more particularly to mechanisms to transmit and convert mechanical energy to electrical energy in such systems.
The section headings used herein are for organizational purposes only and are not to be construed as limiting the subject matter described in any way.
A hydroelectric energy system may utilize a hydroelectric turbine to generate electricity from the current in a moving body of water (e.g., a river or ocean current) or other fluid source. Tidal power, for example, exploits the movement of water caused by tidal currents, or the rise and fall in sea levels due to tides. As the waters rise and then fall, a flow, or fluid current, is generated. The one-directional flow from other bodies of water, such as, for example, from a river, also creates a current that may be used to generate electricity. Additional forms of differential pressure, such as, for example, that are created by dams, also can cause water to flow and create water speeds sufficient to enable the conversion of the horizontal kinetic energy associated with the water's flow to other useful forms of energy.
Hydroelectric energy which relies on the natural movement of fluid currents, such as those occurring in a body of fluid (e.g., water), is classified as a renewable energy source. Unlike other renewable energy sources, such as wind and solar energy, however, hydroelectric energy is reliably predictable. Water currents are a source of renewable power that is clean, reliable, and predictable years in advance, thereby facilitating integration with existing energy grids. Additionally, by virtue of the basic physical characteristics of water (including, e.g., seawater), namely, its density (which can be 832 times that of air) and its non-compressibility, this medium holds unique “ultra-high-energy-density” potential in comparison to other renewable energy sources for generating renewable energy. This potential is amplified once the volume and flow rates present in many coastal locations and/or useable locations worldwide are factored in.
Hydroelectric energy, therefore, may offer an efficient, long-term source of pollution-free electricity, hydrogen production, and/or other useful forms of energy that can help reduce the world's current reliance upon petroleum, natural gas, and coal. Reduced consumption of fossil fuel resources can in turn help to decrease the output of greenhouse gases into the world's atmosphere.
Electricity generation using hydroelectric turbines (which convert kinetic energy from fluid currents into rotational mechanical energy) is generally known. Examples of such turbines are described, for example, in U.S. Pat. No. 7,453,166 B2, entitled “System for Generating Electricity from Fluid Currents;” U.S. Pat. No. 9,359,991 B2, entitled “Energy Conversion Systems and Methods;” U.S. Pat. No. 10,389,209 B2, entitled “Hydroelectric Turbines, Anchoring Structures, and Related Methods of Assembly,” U.S. Pat. No. 10,544,775 B2, entitled “Hydroelectric Energy Systems, and Related Components and Methods;” and U.S. Patent Application Publication No. 2021-0190032 A1, entitled “Hydroelectric Energy Systems and Methods,” which are incorporated by reference herein. Such turbines can act like underwater windmills and have a relatively low cost and ecological impact. In various hydroelectric turbines, for example, fluid flow interacts with blades that rotate about an axis and that rotation (i.e., rotational mechanical energy) is harnessed to thereby produce electricity or other forms of energy.
Hydroelectric energy systems, however, are generally relatively complex and require custom components and parts that can be costly to produce and maintain. Additional challenges also may arise with accessing the turbines for repair and maintenance once the turbine is submerged and installed, for example, in a moving body of water. Various challenges arise in designing and implementing hydroelectric energy generation systems in view of the turbulent nature of the environments in which they are deployed, such as the one-directional (i.e., uni-directional) river flow or the undulations associated with tidal currents, which can produce non-steady input/output and can accelerate corrosion and fatigue issues of the components of the turbine. Furthermore, various additional challenges may arise regarding protecting such turbines and various components of the hydroelectric energy generation system from floating debris that may be carried in the fluid body in which they are deployed. Moreover, the bodies of water being liquid and in some cases of high mineral or salt content, may further exacerbate corrosion and/or wear on parts of hydroelectric energy system.
It may, therefore, be desirable to provide a hydroelectric energy system having a design that facilitates greater ease of access to its components for repair and maintenance requirements. It may be further desirable to provide a hydroelectric energy system having a design that reduces the risk of corrosion and damage to key components of the system.
Exemplary embodiments of the present disclosure may demonstrate one or more of the above-mentioned desirable features. Other features and/or advantages may become apparent from the description that follows.
Additional objects and advantages will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the present teachings. At least some of the objects and advantages of the present disclosure may be realized and attained by means of the elements and combinations particularly pointed out in the appended claims.
In accordance with various exemplary embodiments of the present disclosure, a hydroelectric energy system includes a turbine comprising a stator and a rotor. The rotor is disposed radially outward of the stator and is rotatable around the stator about an axis of rotation. The system may also include a mechanical power conversion assembly including a gear operably coupled to a generator. The system further includes a mechanical power transmission assembly operably coupling the rotor to the gear. The rotor includes a plurality of blades configured to rotate in response to fluid flow interacting with the plurality of blades. The mechanical power conversion assembly is at a location spaced from the axis of rotation by a distance larger than a radial sweep of the blades. The mechanical power transmission assembly is configured to transmit the rotation of the rotor to the gear.
In accordance with various additional exemplary embodiments of the present disclosure, a method of collecting hydroelectric energy includes supporting a turbine in a position submerged within a body of fluid comprising a fluid flow. The turbine comprises a rotor disposed radially outward of a stator and the rotor comprises blades extending radially outward. The method also includes rotating the rotor around the stator about an axis of rotation via the fluid flow interacting with the blades. The method further includes transmitting the rotation of the rotor to a gear supported above the body of fluid. The gear is operatively coupled to a generator supported above the body of fluid.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present disclosure and claims, including equivalents. It should be understood the present disclosure and claims, in their broadest sense, could be practiced without having one or more features of these exemplary aspects and embodiments. For example, those of ordinary skill in the art would understand that the following detailed description related to hydroelectric energy systems and methods are exemplary only, and that the disclosed systems and methods can have various components, which utilize various hydroelectric turbines, mechanical energy transmission components, gear assemblies, and generators to collect, transmit, and convert mechanical energy into electrical energy.
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate various non-limiting embodiments of the present disclosure and together with the description, serve to explain certain principles. In the drawings:
The present disclosure solves one or more of the above-mentioned problems and/or achieves one or more of the above-mentioned desirable features. Other features and/or advantages may become apparent from the description which follows.
The present disclosure contemplates hydroelectric energy systems that can convert horizontal kinetic energy from fluid flow (e.g., from water currents) into rotational mechanical energy. As illustrated generally in
The contemplated hydroelectric energy systems may also transfer the mechanical energy collected by the hydroelectric turbines to a gear and generator (e.g., a mechanical power conversion assembly), where the mechanical energy is converted into electricity. In this manner, the kinetic energy in the fluid flow can be directly converted to electricity using, for example, a number of commercially available gear and generator components with which those having ordinary skill in the art would have familiarity. The gears and generators used for electricity production, however, are prone to corrosion and/or damage when positioned in the fluid flow, or otherwise exposed to water in the vicinity of the hydroelectric turbine. Furthermore, positioning such components underwater with the hydroelectric turbine makes it difficult to service such components for repair and maintenance purposes (e.g., when corroded and/or damaged).
Accordingly, to increase accessibility of such components while not interfering with the operation of the turbine, embodiments of the present disclosure contemplate positioning the mechanical power conversion components (e.g., gear assembly and generator) at a position remote from the turbine, for example, at a location spaced from the axis of rotation of the turbine by a distance larger than a radial sweep of the blades of the turbine. The contemplated hydroelectric energy systems and methods are, therefore, configured to transmit the mechanical energy generated by the rotation of the turbine to a mechanical power conversion assembly that is positioned at a location spaced from the axis of rotation by a distance larger than a radial sweep of the blades.
When in use within a body of fluid (e.g., a body of water), to reduce the risk of corrosion and damage to such components, while increasing accessibility and safety for the purposes of maintenance and/or replacement, various embodiments of the present disclosure contemplate hydroelectric energy systems and methods that transmit the mechanical energy generated by the rotation of the hydroelectric turbine to a sealed mechanical power conversion assembly (e.g., gear assembly and generator) that is supported above the water line, where it is then converted to electricity. Accordingly, in various embodiments, the mechanical conversion assembly is placed at a distance (from the axis of rotation of the turbine) that is sufficient to enable the turbine to be submerged in a body of fluid (e.g., body of water) comprising the fluid flow, while the mechanical power conversion assembly is above a surface of the body of fluid
In this manner, hydroelectric energy systems in accordance with the present disclosure, have an architecture that allows energy collection from the fluid current to occur at one location and electricity generation to occur at a different location. More specifically, in embodiments disclosed herein, hydraulic energy is initially collected and converted into mechanical energy by means of the hydroelectric turbine that is submerged in the fluid flow (e.g., current). The resulting mechanical energy (i.e., rotation of the rotating member) is consolidated at an output of the turbine and transmitted through a mechanical power transmission assembly to a mechanical power conversion assembly (e.g., gear and induction generator) housed in a housing above the body of fluid, where it is converted into electrical energy suitable for direct connection to a standard micro-grid.
Using mechanical power transmission assemblies in accordance with various embodiments to transmit the mechanical energy generated at the submerged turbine to a location outside the body of fluid permits the various gearing and electricity generating elements of the hydroelectric energy systems to be protected from the relatively harsh environment (e.g., aqueous environment) of the fluid, as well as facilitating the ability to service such components.
Moreover, as will be better understood from the following description, various embodiments of mechanical power transmission assemblies disclosed herein accommodate for the changing velocities of the rotating turbine that may occur due to the nature of the currents and permit the mechanical energy to be transmitted at a more predictable and uniform manner that is input at the mechanical power conversion assembly
The hydroelectric energy systems 100, 200 further comprise floatation structures 120, 220 that are configured to support the hydroelectric turbines 101, 201 within a fluid flow F (see
Each hydroelectric turbine 101, 201 comprises a stator 102, 202 and a rotor 104, 204, the latter of which includes a plurality of blades 106, 206 configured to interact with a fluid flow F to cause the rotor 104, 204 to rotate. Nonlimiting embodiments of hydroelectric turbines that may be used are described, for example, with reference to
As illustrated best perhaps in
In accordance with an embodiment, the support structure 124, 224 is further configured to raise and lower the hydroelectric turbine 101, 201 between a first, deployed position in which the turbine 101, 201 is positioned below the catamaran hulls 122, 222 and in the fluid flow to collect kinetic energy, and a second, stowed position in which the hydroelectric turbine 101, 201 is raised out of the fluid (i.e., above a surface of the body of fluid (e.g., water line) 150, 250) so as to allow for service, repair, and/or maintenance of the turbine and/or maneuvering of the catamaran. Various embodiments of the present disclosure contemplate, for example, suspending the hydroelectric turbine 101, 201 via a hydraulic support structure 124, 224 including a frame 126, 226 that is attached to the hulls 122, 222 of the catamaran via pivots 127, 227 and telescopic hydraulic lifts 128, 228.
To convert the high torque, low speed power collected by the turbine 101, 201 to a low torque, high speed input suitable for a generator, embodiments of the present disclosure further contemplate utilizing a mechanical power conversion assembly 130, 230, which couples the generator to a gear assembly. With reference to
Those of ordinary skill in the art would understand that the hydroelectric turbines 101, 201, floatation structures 120, 220, support structures 124, 224, and mechanical power conversion assemblies 130, 230 illustrated in the embodiments of
It will also be understood that various mechanical power conversion assemblies, utilizing various configurations and/or combinations of gears and generators, may be used to convert the rotational mechanical energy collected by the turbine into electricity. Although the illustrated embodiments depict power generation components such as a mechanical gear assembly that is coupled to an induction generator, in another embodiment, the generator may be coupled to a magnetic gear, such as, for example, an orbital magnetic gear, as disclosed in International Patent Application Publication No. WO/2020/118151, entitled “Orbital Magnetic Gear, and Related Systems,” which is incorporated by reference in its entirety herein.
Various exemplary embodiments further contemplate the use of modular architectures employing electrical power generation equipment designed to operate at speeds appropriate for 6 and 8 pole induction motors, e.g., 1200 and 900 rpm. Both types of induction motors are commercially available and come in sizes that are conducive to applications associated with the embodiments of hydroelectric energy systems disclosed herein. While mechanical gears may also be used to convert the low speed, high torque at the turbine to high speed, low torque at the generator, they may be more prone to wear and other damage. Using magnetic gears thus can provide further advantages regarding maintenance and efficiency. As discussed in International Patent Application Publication No. WO/2020/118151, using the magnetic gears can alleviate other issues, such as vibration and friction, that can result in wear and damage.
Further, the use of such magnetic gears may increase the turbine's hydrodynamic power generation efficiency, or power coefficient of the rotating member. Specifically, the magnetic gear may allow for more reliable operations with reduced maintenance and downtime since it is a non-contacting device that requires no lubrication between bearing components and little routine maintenance. In addition, the magnetic gear achieves reduced losses further improving the turbine's efficiency.
Turning again to the embodiment of
As perhaps best illustrated in
As illustrated in
The second CV joint 116, at the opposite end 117 of the CV axle, couples the CV axle 112 to the gear assembly 132 of the mechanical power conversion assembly 130. In one embodiment, a rotating shaft end portion 119 (see
Those of ordinary skill in the art will understand that the CV axle 112 and the CV joints 114 and 116 of the mechanical power transmission assembly 110 are exemplary only, and that various types, numbers, sizes and/or configurations of CV axles and joints may be utilized within the systems and methods of the present disclosure (i.e., based on a particular application) to transmit the mechanical rotational energy collected by the turbine 101 submerged in the body of fluid to a location out and above the surface of the body of fluid. Furthermore, it will be understood that the CV joints 114 and 116 may be respectively coupled to the rotor 104 and the gear assembly 132 via any known coupling mechanisms.
Turning now to the embodiment of
As illustrated in
The mechanical power transmission assembly 210 also includes a second profiled wheel 216, such as, for example, a second toothed sprocket, that is coupled to the gear assembly 232 of the mechanical power conversion assembly 230 and is configured to mesh with the belt 212. In various embodiments, the profiled wheel 216 is mounted to the gear assembly 232 adjacent the housing 236, such that the belt 212 attaches to the gear assembly 232 at a location that does not interfere with the gears of the assembly. Similar to the embodiment of
As would be understood by those of ordinary skill in the art, the rim speed of the profiled wheel 214 and the turbine 201 will be the same for a given velocity of current. Therefore, the larger the turbine, the slower the rotation of the rotor 204 and the slower the revolutions per minute (RPMs) of the profiled wheel 214. As the generator 234 generally requires a high RPM to function properly (i.e., the generator generally requires a low torque, high speed input), embodiments of the present disclosure contemplate magnifying the RPMs of the profiled wheel 214 to produce higher RPMs in the profiled wheel 216 for input into the mechanical power conversion assembly 230, which also results in a lower wheel torque to the mechanical power conversion assembly 230. The profiled wheels 214 and 216 may, therefore, be sized to create a wheel ratio that functions to magnify the RPMs of the profiled wheel 216 (thereby reducing the magnification requirement of the gear assembly 232), while also preventing unnecessary wear in the belt 212 (e.g., as it rounds the profiled wheel 216). In various embodiments, for example, the profiled wheels 214 and 216 may be sized to create a wheel ratio between the profiled wheels (216:214) of about 8:1 to about 12:1. Those or ordinary skill in the art would understand that various ratios of sizes and profiles of the profiled wheels 214 and 216 can be selected to provide an appropriate wheel ratio for the transmission of power, based on a given application.
To protect the belt 212, for example, from debris within the fluid body (e.g., water), in various embodiments, the mechanical power transmission assembly 210 also includes a guard 218 that encases one or more portions of the belt 212. As illustrated in
Those of ordinary skill in the art will understand that the mechanical power transmission assembly 210 that utilizes the belt drive assembly including the belt 212, guards 218, and the profiled wheels 214 and 216 are exemplary only, and that various types, numbers, sizes and/or configurations of belts, guards, and/or wheels may be utilized within the systems and methods of the present disclosure (i.e., based on a particular application) to transmit the mechanical rotational energy collected by the turbine 201 to a location outside and above the surface of the body of fluid. For example, although in the embodiment of
Furthermore, it will be understood that that the wheels 214 and 216 may be respectively coupled to the rotor 204 and the gear assembly 232 via any known methods and/or techniques and are not limited to the embodiment shown and described herein.
Accordingly, embodiments of the present disclosure contemplate hydroelectric energy systems having architectures that facilitate maintenance and life of electricity generation components. The use of mechanical power transmission assemblies, such as, CV axle mechanisms and belt drive assemblies, allows the gears and generators associated conversion of mechanical energy to electrical energy to be placed above the surface of the body of fluid in which the forces of the fluid flow are initially collected at the turbine, facilitating greater ease of access for any maintenance required, and reducing the risk of corrosion and damage to those electricity generation and mechanical energy conversion components.
CV axles/joints and belts have also been found to be robust and relatively inexpensive. Hydroelectric energy systems, utilizing such components, therefore also optimize the cost and efficiency of the electricity generation components of the system, thereby reducing the overall manufacture and maintenance costs of the system.
This description and the accompanying drawings that illustrate exemplary embodiments should not be taken as limiting. Various mechanical, compositional, structural, electrical, and operational changes may be made without departing from the scope of this description and the claims, including equivalents. In some instances, well-known structures and techniques have not been shown or described in detail so as not to obscure the disclosure. Furthermore, elements and their associated features that are described in detail with reference to one embodiment may, whenever practical, be included in other embodiments in which they are not specifically shown or described. For example, if an element is described in detail with reference to one embodiment and is not described with reference to a second embodiment, the element may nevertheless be included in the second embodiment.
It is noted that, as used herein, the singular forms “a,” “an,” and “the,” and any singular use of any word, include plural referents unless expressly and unequivocally limited to one referent. As used herein, the term “include” and its grammatical variants are intended to be non-limiting, such that recitation of items in a list is not to the exclusion of other like items that can be substituted or added to the listed items.
Further, this description's terminology is not intended to limit the disclosure. For example, spatially relative terms—such as “upstream,” downstream,” “beneath,” “below,” “lower,” “above,” “upper,” “forward,” “front,” “behind,” and the like—may be used to describe one element's or feature's relationship to another element or feature as illustrated in the orientation of the figures. These spatially relative terms are intended to encompass different positions and orientations of a device in use or operation in addition to the position and orientation shown in the figures. For example, if a device in the figures is inverted, elements described as “below” or “beneath” other elements or features would then be “above” or “over” the other elements or features. Thus, the exemplary term “below” can encompass both positions and orientations of above and below. A device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.
Further modifications and alternative embodiments will be apparent to those of ordinary skill in the art in view of the disclosure herein. For example, the systems may include additional components that were omitted from the diagrams and description for clarity of operation. Accordingly, this description is to be construed as illustrative only and is for the purpose of teaching those skilled in the art the general manner of carrying out the systems and methods of the present disclosure. It is to be understood that the various embodiments shown and described herein are to be taken as exemplary. Elements and materials, and arrangements of those elements and materials, may be substituted for those illustrated and described herein, parts and processes may be reversed, and certain features of the present teachings may be utilized independently, all as would be apparent to one skilled in the art after having the benefit of the description herein. Changes may be made in the elements described herein without departing from the scope of the present disclosure.
It is to be understood that the particular examples and embodiments set forth herein are non-limiting, and modifications to structure, dimensions, materials, and methodologies may be made without departing from the scope of the present disclosure. Other embodiments in accordance with the present disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. It is intended that the specification and examples be considered as exemplary only, with being entitled to their full breadth of scope, including equivalents.
This application claims priority to U.S. Provisional Patent Application No. 63/114,770, filed Nov. 17, 2020 and entitled “Hydroelectric Energy Systems and Methods Utilizing a Constant Velocity Axle,” the entirety of which is incorporated by reference herein.
Filing Document | Filing Date | Country | Kind |
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PCT/US21/59497 | 11/16/2021 | WO |
Number | Date | Country | |
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63114770 | Nov 2020 | US |