Embodiments of the subject matter described herein relate generally to solar energy systems which include drive systems for sun-tracking, solar energy collecting devices.
Some larger solar collector installations include arrays of sun-tracking, solar power collector assemblies. Such assemblies can be used in conjunction with photovoltaic modules, concentrated photovoltaic modules, as well as concentrated thermal solar collector devices.
Sun-tracking solar energy systems include hardware for automatically adjusting the position of the collector devices to track the sun as it moves across the sky. Some known systems include parallel rows of solar energy collection devices supported on pivoting shafts, known as “torque tubes.” The torque tubes are pivoted to tilt the solar energy collection devices so as to track the movement of the sun.
Further, some systems (a.k.a. “ganged” systems) include a reduced number of drive devices, for example, where each drive device is connected to a plurality of parallel torque tubes. Such systems can benefit from the cost reduction of using fewer drives, which can include expensive electric motors, control circuitry, and other hardware.
An aspect of at least one of the inventions disclosed herein includes the realization that some types of solar tracking systems, such as those including a plurality of parallel rows of solar energy collectors driven with a common drive, can benefit from reduced labor and hardware costs by utilizing certain common components for various different applications within a system having a plurality of connected ground based supports for supporting a drive unit of a “ganged” sun-tracking solar power system.
For example, “ganged” sun-tracking solar power systems include a series of drive links extending from a drive actuator, to pivoting connections at each of a number of parallel torque tubes. Such pivoting connections can include bearings or simple pin-hole connections. Such connections are also connected to a torque arm associated with each torque tube. Thus, as the drive links are moved by the drive actuator, the torque tubes are pivoted. However, due to the nature of “ganged” systems, the total loads imparted to the sun-tracking drive system can be quite large.
For example, some known solar power systems which have 18 parallel torque tubes can generate loads of 30,000-50,000 lbs. of force, for example, when snow-loaded or subject to high winds. Thus, some known solar system designs include large, heavy and expensive drive mounts to withstand the maximum load design parameters of such systems.
An aspect of at least one of the embodiments disclosed herein includes the realization that certain components for supporting parallel torque tubes can also be used for supporting a drive used for moving the torque tubes in a sun tracking movement. For example, in some known designs, the torque tubes of such systems are supported by a plurality of pile driven support members. However, a single one of such pile driven support members would not normally be sufficient for anchoring a drive used for pivoting a plurality of torque tubes. Bus, an aspect of at least one of the embodiments disclosed herein includes the realization that a plurality of such pile driven supports can be used to replace the large, heavy, expensive drive mounts typically used for such systems.
Thus, in accordance with an embodiment, a sun tracking solar power system including a plurality of parallel arrays of sun tracking solar energy collection devices can comprise a plurality of spaced apart support members supporting each of the plurality of parallel arrays of sun tracking solar energy collection devices, a sun tracking drive connected to the plurality of parallel arrays and configured to drive the parallel arrays race on tracking movement, and a plurality of the support members supporting and fixing the sun tracking drive relative to the plurality of parallel arrays.
In some embodiments, a solar energy collection system can comprising a first array of solar energy collection devices mounted so as to be movable between first and second positions, the first array of solar energy collection devices can be mounted to a first rotational member assembly supported above the ground by a first plurality of support members which are fixed to the ground. A second array of solar energy collection devices can be spaced from the first array, the second array of solar energy collection devices can be mounted to a second rotational member assembly supported above the ground by a second plurality of support members. A drive system can comprise an actuator, a drive link assembly connecting the actuator with the first and second arrays. An actuator support can supporting the actuator above the ground, the actuator support comprising a third plurality of support members fixed to the ground and connected together.
Additionally, in some embodiments, a solar energy collection system can comprise a first array of solar energy collection devices mounted so as to be movable between first and second positions, the first array of solar energy collection devices can be mounted to a first rotational member assembly. A second array of solar energy collection devices can be spaced from the first array, the second array of solar energy collection devices can be mounted to a second rotational member assembly. A drive system can comprise an actuator, a drive link assembly connecting the actuator with the first and second arrays. An actuator support can support the actuator above the ground, the actuator support can be configured to allow an orientation of the actuator to be adjusted between a plurality of different orientations relative to the first and second arrays of solar energy collection devices.
This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.
A more complete understanding of the subject matter may be derived by referring to the detailed description and claims when considered in conjunction with the following figures, wherein like reference numbers refer to similar elements throughout the figures.
The following detailed description is merely illustrative in nature and is not intended to limit the embodiments of the subject matter or the application and uses of such embodiments. As used herein, the word “exemplary” means “serving as an example, instance, or illustration.” Any implementation described herein as exemplary is not necessarily to be construed as preferred or advantageous over other implementations. Furthermore, there is no intention to be bound by any expressed or implied theory presented in the preceding technical field, background, brief summary or the following detailed description.
This specification includes references to “one embodiment” or “an embodiment.” The appearances of the phrases “in one embodiment” or “in an embodiment” do not necessarily refer to the same embodiment. Particular features, structures, or characteristics may be combined in any suitable manner consistent with this disclosure.
Various units or components may be described or claimed as “configured to” perform a task or tasks. In such contexts, the phrase “configured to” is used to connote structure by indicating that the units/components include structure that performs those task or tasks during operation. As such, the unit/component can be said to be configured to perform the task even when the specified unit/component is not currently operational (e.g., is not on/active). Reciting that a unit/circuit/component is “configured to” perform one or more tasks is expressly intended not to invoke 35 U.S.C. §112, sixth paragraph, for that unit/component.
“First,” “Second,” etc. as used herein, these terms are used as arbitrary labels for nouns that they precede, and do not imply any type of ordering (e.g., spatial, temporal, logical, etc.). For example, reference to a “first” solar module does not necessarily imply that this solar module is the first solar module in a sequence; instead the term “first” is used to differentiate this solar module from another solar module (e.g., a “second” solar module).
As used herein, the term “based on” describes one or more factors that affect a determination. This term does not foreclose additional factors that may affect a determination. That is, a determination may be solely based on those factors or based, at least in part, on those factors. Consider the phrase “determine A based on B.” While B may be a factor that affects the determination of A, such a phrase does not foreclose the determination of A from also being based on C. In other instances, A may be determined based solely on B.
The following description refers to elements, nodes, or features being “coupled” together. As used herein, unless expressly stated otherwise, “coupled” means that one element/node/feature is directly or indirectly joined to (or directly or indirectly communicates with) another element/node/feature.
Some elements, components, and/or features are described as being adjustable or adjusted. As used herein, unless expressly stated otherwise, “adjust” means to position, modify, alter, or dispose an element or component or portion thereof as suitable to the circumstance and embodiment. In certain cases, the element or component, or portion thereof, can remain in an unchanged position, state, and/or condition as a result of adjustment, if appropriate or desirable for the embodiment under the circumstances. In some cases, the element or component can be altered, changed, or modified to a new position, state, and/or condition as a result of adjustment, if appropriate or desired.
In addition, certain terminology may also be used in the following description for the purpose of reference only, and thus are not intended to be limiting. For example, terms such as “upper”, “lower”, “above”, and “below” refer to directions in the drawings to which reference is made. Terms such as “front”, “back”, “rear”, and “side” describe the orientation and/or location of portions of the component within a consistent but arbitrary frame of reference which is made clear by reference to the text and the associated drawings describing the component under discussion. Such terminology may include the words specifically mentioned above, derivatives thereof, and words of similar import.
The inventions disclosed herein are described in the context of non-concentrated photovoltaic arrays and modules. However, these inventions can be used in other contexts as well, such as concentrated photovoltaic systems, thermal solar systems, concentrated thermal solar systems, etc.
In the description set forth below, a solar energy collection system 10 is described in the context of a plurality of solar collection modules, supported so as to be pivotally adjustable for sun-tracking purposes. Each of the modules can include a support arrangement supporting a plurality of solar collection devices as well as wiring for connecting the various solar collection devices to each other and to other modules. For example, the solar collection system 10 of
The solar collection system 10 includes a solar collector array 11 which includes a plurality of solar collection modules 12. Each of the solar collection modules 12 can include a plurality of solar collecting devices 14 (e.g., solar cells) incorporated into a laminate and encircled by a peripheral frame. The modules 12 can be supported by a drive shaft or torque tube 16.
Each of the torque tubes 16 are supported above the ground by a support assembly 18. Each of the support assemblies 18 can include a pile 22 and a bearing assembly 20. The piles 22 can be in the form of any type of pile, for example, those types of piles which can be “pile-driven” into the ground for providing structural support. For example, but without limitation, the piles 22 can be in the form of C-shaped channel structural steel, or other types of piles.
With continued reference to
Additionally, the solar collection devices 14 can be in the form of thermal solar collection devices, concentrated photovoltaic devices, or concentrated thermal solar collection devices. In the illustrated embodiment, the solar collection devices 14 are solar cells configured for non-concentrated photovoltaic modules 12.
With reference to
The tilt drive 30 can include a drive strut 32 coupled with the torque tube 16 in a way that pivots the torque tube 16 as the drive strut 32 is moved axially along its length. The drive strut 32 can be connected with the torque tube 16 with torque arm assemblies 34. In the illustrated embodiment, the torque arm assemblies 34 disposed at an end of each of the torque tubes 16. Additionally, the array 11 can include an electrical wire tray 60 supported by one or more of the piles 22, or by other means.
With reference to
The controller 50 performs calculations for controlling the drive 30 so as to orient the modules 12 as closely as possible to an orientation perpendicular to the sunlight 54, without casting a shadow on adjacent modules 12. In other words, the controller 50 causes the modules 12 to rotate through a range of non-optimal orientations, which produces less power than a perpendicular orientation, so as to avoid casting shadows which have a greater detrimental effect on total power output of the system 10.
With reference to
With reference to
While the modules 12 are tilted in before noon orientations (i.e., all positions when modules 12 are tilted eastwardly relative to a “noon” position) and afternoon orientations (i.e., all positions when modules 12 are tilted westwardly relative to a “noon” position), gravity generates some torque on the torque tubes 16 which is transferred to the torque arms 34. The gravity-induced torque is caused by the position of the center of gravity of the array, which tends to be above the pivot axis of the torque tube 16, during before-noon positions of the modules 12.
The torque generated during before-noon orientations of the modules 12, is transferred through the torque arm 34 to the drive struts 32. The drive struts 32 can comprise a plurality of link members connected in an end-to-end fashion and additionally connected to an end of the torque arm 34. The torque thus generates tension forces in the drive links. Similarly, when the modules 12 are oriented in after-noon orientations, the gravity-induced torques are transferred through the torque arms 34 to the drive struts 32 in the form of compressive forces which are resisted by the drive assembly 30.
Additionally, loads created by other matter collecting on the modules 12 can generate additional loads. For example, significant amounts of snow can accumulate the upper surface of the modules 12, thereby generating even higher torques and loads. Thus, for some sizes of solar systems 10, such systems including 18 rows of torque tubes 16, the drive assembly 30 can be subjected to axial loads, in the form of tension and compression of the drive struts 32 as high as 30,000 to 50,000 pounds.
Using 50,000 pounds as an exemplary maximum design load parameter for the drive assembly 30 establishes the drive assembly 30 as the component which is exposed to the highest loads in the entire system 10, by a significant margin. Thus, known existing systems similar to that illustrated in
An aspect of at least one of the inventions disclosed herein includes the realization that significant amount of labor costs, material costs and construction time can be avoided by forming a drive mount base from a plurality of other support structures used for supporting other parts of the solar system 10.
Thus, with reference to
For example, in the illustrated embodiment, the mounting base 100 includes a plurality 102 of piles 22 which are similar to or the same as piles 22 illustrated in
With continued reference to
As such, during construction of a system 10, the piles 22 forming the plurality of supports 102 can be installed into the ground G at approximately the same time, for example, during the same construction phase as that during which the piles 22 supporting the torque tube 16 are driven into the ground G.
The mounting base 100 can also include a load sharing assembly 104. The load sharing assembly 104 can be configured to interconnect two or more of the plurality of load support members 102 so as to spread loads amongst the plurality of support members. Thus, in the illustrated embodiment, the load sharing assembly 104 includes interconnection member 106 and interconnection member 108, each of which connect a plurality of the piles 22 together. In the illustrated embodiment, the interconnection members 106 and 108 are in the form of structural “angle steel”. However, other configurations of the interconnection members 106, 108 can also be used.
Optionally, the interconnection members 106, 108 and the associated piles 22 can include apertures for receiving fasteners, such as threaded fasteners, to simplify assembly at a solar facility site. In the illustrated embodiment, the apertures on the piles 22 are formed on the webs 23 and the apertures on the interconnection members 106, 108 are formed on the vertical portions of those frame members, positioned for alignment with the apertures on the webs 23. With such apertures attached, for example, with threaded fasteners, parts of the interconnection members 106, 108 each are oriented horizontally, referred to herein as horizontally extending portions 110, 112.
Additionally, optionally, the interconnection members 106, 108 can extend to piles 22 supporting the torque tube 16. As such, the interconnection members 106, 108 can also be attached to the piles 22 supporting the torque tube 16. Additionally, such connections can be facilitated with pre-drilled apertures for receiving threaded fasteners. However, other techniques can also be used.
Optionally, an alignment tool 114 can be used during installation of the interconnection members 106, 108 to ensure proper spacing between the upper surfaces 110, 112 and otherwise proper alignment of the support frame members 106, 108.
With the plurality of support members 102 connected in a way so as to share a load, the tensile loads acting in the direction of arrow T (
Thus, for example, in a system 10 with a maximum load parameter of 50,000 pounds compression or tension and based on the height of the load sharing assembly 104, each individual pile 22 could withstand approximately 10,000 pounds of compression C or tension T. However, combined with the load sharing assembly 104, the plurality of support members 102 can withstand maximum loads up to approximately 60,000 pounds of compression C or tension T. Thus, depending on the design parameters of a particular system, the number of piles 22 and/or types of support members used in the plurality of support members 102 can be modified.
With reference to
For example, the jackscrew drive 122 can include an electric motor, a worm gear-type transmission, and a jackscrew member 124 and can be configured to drive the jackscrew member 124 through a reciprocating, east-west movements, for driving the drive struts 32 in the desired directions. Such actuators 122 can include an annular or cylindrical mounting face extending around the jackscrew 124, for example, with a bolt hole pattern or other attachment device configured to attach to a drive mount. Such actuators 122 are well known in the art and widely commercially available. Thus, the actuator 122 is not described further.
With continued reference to
For example, optionally, the actuator mount 120 can be configured for fixation to the load sharing assembly 104 of the mount base 100. In some embodiments, the actuator mount member 120 includes first and second mounting portions 140, 142 configured to be fixable to the interconnecting members 106, 108, respectively. For example, the mounting portions 140, 142 can be formed with structural members, such as plate steel, or other members, and a plurality of apertures for fixation to the frames 106, 108 with fasteners, such as threaded fasteners. With continued reference to
With the continued reference to
With reference to
For example, with continued reference to
Optionally, with continued reference to
With continued reference to
In some embodiments, the adjustable actuator mount member 170 includes a mounting face 172 and one or more actuator mounting arms 174. The actuator mounting arms 174 can include one or more apertures 176 configured to be fixable to the actuator 122. In the illustrated embodiment, the arms 174 and apertures 176 are configured to securely attach to a worm gear housing of the actuator 122, because the actuator 122 is designed to be supported by the worm gear casing. Other actuators can be supported with other types of mounting arms 174 and/or apertures 176.
The mounting plate 172 also includes a central aperture 178 configured to accommodate the jackscrew 124 (
The mounting plate 172, as noted above, is configured to be adjustably mountable to the mounting face 150. Thus, in some embodiments, the mounting plate 172 includes a plurality of slotted upper and lower apertures 180, 182 configured to be attachable to the upper and lower apertures 154, 156 of the mounting face 150.
More specifically, with reference to
Optionally, in the illustrated embodiment, the upper and lower apertures 180 are slotted and extend along arched paths. For example, the curved slotted configurations of the upper and lower apertures 180, 182 further facilitate rotational adjustment of the member 170 relative to the mounting surface 150. Optionally, the upper and lower apertures 180, 182 can extend along a radius of curvatures centered approximately in the central aperture 178.
Additionally, in some embodiments, the mount assembly 120 can also include a clamping plate 190 configured to be attachable to the member 170 with the mounting face 150 disposed there between. Thus, the clamping plate 190 includes a central aperture 192 shaped and configured to be alignable with the central aperture 178 of the member 170 and the central aperture 152 of the mounting face 150. Additionally, the clamping plate member 190 can also include a plurality of apertures configured to be alignable with the upper and lower apertures 180, 182 of the member 170 for receiving fasteners, such as threaded fasteners. As such, the clamping plate 190 and the member 170 can be secured together, with the mounting face 150 clamped there between for secure fixation thereto.
As noted above, the configuration of the upper and lower apertures 180, 182 can provide for beneficial adjustment of the member 170 relative to the face 150.
One example of an installation configuration is illustrated in
Thus, as illustrated in
With reference to
Although specific embodiments have been described above, these embodiments are not intended to limit the scope of the present disclosure, even where only a single embodiment is described with respect to a particular feature. Examples of features provided in the disclosure are intended to be illustrative rather than restrictive unless stated otherwise. The above description is intended to cover such alternatives, modifications, and equivalents as would be apparent to a person skilled in the art having the benefit of this disclosure.
The scope of the present disclosure includes any feature or combination of features disclosed herein (either explicitly or implicitly), or any generalization thereof, whether or not it mitigates any or all of the problems addressed herein. Accordingly, new claims may be formulated during prosecution of this application (or an application claiming priority thereto) to any such combination of features.
This application claims the benefit of U.S. Provisional Application No. 62/099,978 filed Jan. 5, 2015, entitled “Solar Tracker Drive” by Lambert et al., the entire contents of which are hereby incorporated by reference.
Number | Date | Country | |
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62099978 | Jan 2015 | US |