U.S. patent application number 12/304967 was filed with the patent office on 2009-12-31 for solar array tracker controller.
This patent application is currently assigned to THOMPSON TECHNOLOGY INDUSTRIES, INC.. Invention is credited to Eric Carlson, David Shevick, Daniel S. Thompson.
Application Number | 20090320827 12/304967 |
Document ID | / |
Family ID | 38846534 |
Filed Date | 2009-12-31 |
United States Patent
Application |
20090320827 |
Kind Code |
A1 |
Thompson; Daniel S. ; et
al. |
December 31, 2009 |
SOLAR ARRAY TRACKER CONTROLLER
Abstract
A solar array tracker controller including an operator
programmable micro- processor electronically connected to the drive
motors in a solar panel array or other solar device array. The
processor is user programmable and includes memory for storing a
software program which includes an algorithm that determines the
precise location of the sun relative to the array based on the
local data input into the processor A GPS sensor and interface may
be provided to obviate the need for local
Inventors: |
Thompson; Daniel S.; (San
Rafael, CA) ; Carlson; Eric; (San Francisco, CA)
; Shevick; David; (San Rafael, CA) |
Correspondence
Address: |
STAINBROOK & STAINBROOK, LLP
412 AVIATION BOULEVARD, SUITE H
SANTA ROSA
CA
95403
US
|
Assignee: |
THOMPSON TECHNOLOGY INDUSTRIES,
INC.
Novato
CA
|
Family ID: |
38846534 |
Appl. No.: |
12/304967 |
Filed: |
June 28, 2007 |
PCT Filed: |
June 28, 2007 |
PCT NO: |
PCT/US07/72325 |
371 Date: |
December 15, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60806072 |
Jun 28, 2006 |
|
|
|
Current U.S.
Class: |
126/576 |
Current CPC
Class: |
F24S 50/20 20180501;
Y02E 10/47 20130101 |
Class at
Publication: |
126/576 |
International
Class: |
F24J 2/38 20060101
F24J002/38 |
Claims
1. A solar array tracker controller, comprising an operator
programmable microprocessor/controller electronically connected to
one or more drive motors in a solar device array, said processor
having magnetic storage means for storing a software program which
includes an algorithm that determines the precise location of the
sun relative to the array based on the local data input into the
processor, an operator interface, a visual display, and input means
for entering local data regarding the location of the solar array
to be controlled and for programming said processor with said
software.
2. The apparatus of claim 1, wherein said software includes an
algorithm that takes into account the elliptical orbit of the earth
around the sun in determining the location of the sun.
3. The apparatus of claim 1, further including a GPS interface for
a Global Positioning Sensor that provides information to said
processor concerning the latitude, longitude and global time.
4. The apparatus of claim 1, further including at least one
inclinometer in electronic communication with said processor and
mounted on one or more of the axes of a solar energy utilizing
device and wherein said processor includes a digital interface for
receiving data from said inlinometer.
5. The apparatus of claim 4, wherein said inclinometer provides
data regarding the angle of altitude and azimuth of at least one
device in the solar device array.
6. The apparatus of claim 1, wherein said processor further
includes a remote interface that allows remote acquisition and
transmission of data and status of array and of the solar array
tracker controller.
7. The apparatus of claim 1, further including a wind sensor having
electronics for digitizing a wind sensor signal for input into said
processor.
8. A method of controlling drive motors operatively connected to
solar panels in a solar panel array so as to ensure that the panels
have an optimal angle of incidence to solar rays, said method
comprising the steps of: electrically connecting an operator
programmable micro-processor to one or more of the drive motors in
the solar device array, wherein the processor includes input means
and magnetic storage means for entering and storing a program and
local data; programming the processor with a program which includes
an algorithm that determines the precise location of the sun
relative to the array based on the local data and that sends
control signals to the drive motors to move the solar panels into
an optimal position relative to the sun.
9. The method of claim 8, further including the step of providing
the processor with a GPS interface and connecting the processor to
a Global Positioning Sensor that provides information to the
processor concerning the latitude, longitude and global time.
10. The method of claim 8, further including the step of mounting
at least one inclinometer to at least one of the solar panels in
the solar panel array, and connecting the inclinometer to the
processor such that the inclinometer can provide panel tilt data to
the processor.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Technical Field
[0002] The present invention relates generally to solar array
tracker controllers, more particularly to a solar array tracker
controller which utilizes inputs of the local latitude, longitude,
universal time and software incorporating a mathematical algorithm
that calculates the optimal positioning of the solar array and
initiate movements to achieve the optimal positioning.
[0003] 2. Background Art
[0004] Automated solar tracker controllers are widely used to
optimize positioning of solar panels. Solar energy collectors
perform most efficiently when the incident rays of the sun are
perpendicular to the absorbing surface. And because the position of
the sun is constantly changing in relationship to the earth, it is
necessary to continually reposition the absorbing surface of solar
panels to maintain the most advantageous, perpendicular angle of
incidence to the sun's rays. Various solar collector drive
mechanisms and tracker controls have been devised for maintaining
this optimal angle. The following are exemplary, though by no means
exhaustive.
[0005] U.S. Pat. No. 4,175,391 to Baer, describes apparatus for
causing a solar energy collector to follow the sun by using solar
radiant energy to differentially heat fluid-containing reservoirs
to cause differential vaporization and shifting of fluid to rotate
the apparatus. Automatic morning orientation is included by
providing the easterly reservoir with a faster rate of cooling than
the westerly one, thereby causing shift of fluid from westerly to
easterly after sunset resulting inclination toward the east by
sunrise.
[0006] U.S. Pat. No. 4,104,521 to Winders, teaches a high angular
accuracy sensor and tracking device utilizing a symmetrical sensor
shade and sensor arrangement. The apparatus utilizes a circuit
control for the electric motor drive of the tracker.
[0007] U.S. Pat. No. 4,215,521 to Weslow, et al., discloses an open
loop servo controller for motors driving solar panels about its
azimuth and altitude axis to track the sun. The controller has a
central processing unit and a user interface for inputting data
relating to the present day, hour, minute, and the latitude and
longitude of the installed device. Program data and tables of data
corresponding to the declinations of the sun on any day, and other
mathematical functions are stored in memory. The processor utilizes
the data to calculate the azimuth and altitude of the sun for every
minute of the day and issues control signals that cause motors to
move the device to the calculated angles.
[0008] U.S. Pat. No. 4,469,899 to Moore, describes an apparatus for
tracking the motion of the sun utilizing a plurality of solar cells
that generate electric signals when exposed to solar radiation. The
solar cells are mounted in trough-like shadow boxes which permit
exposure of the solar cells to solar radiation only at
predetermined angles. The shadow boxes are mounted for concomitant
rotation around a vertical and horizontal axis and are driven by a
pair of motors. The motors are controlled by the output of the
solar cells and reposition the shadow boxes to shade the solar
cells responsive to the motion of the sun.
[0009] While the above-described patents are each directed to
apparatus for solar tracking and describe devices that initiate
movement of solar energy utilizing devices, none describe a system
incorporating a GPS interface that instantly and constantly updates
the location and time of the solar panel system and thereby
situates the system relative to the sun according to the date and
time. Additionally, none describe a remote interface to the
Internet for remote access to the controlling device. The present
invention, as described and claimed herein, provides such features,
as well as several other advantages and improvements over the prior
art.
[0010] The foregoing patents reflect the current state of the art
of which the present inventors are aware. Reference to, and
discussion of, these patents is intended to aid in discharging
Applicants' acknowledged duty of candor in disclosing information
that may be relevant to the examination of claims to the present
invention. However, it is respectfully submitted that none of the
above-indicated patents disclose, teach, suggest, show, or
otherwise render obvious, either singly or when considered in
combination, the invention described and claimed herein.
DISCLOSURE OF INVENTION
[0011] The present invention is a solar array tracker controller
that utilizes inputs relating to local latitude, longitude, and
universal time, and then based on the inputs employs a mathematical
algorithm to calculate the optimal positioning of the solar array
and to initiate movement of solar collectors to achieve the optimal
positioning. While suitable for use with even a single photovoltaic
or solar collector panel, the tracker controller of the present
invention is particularly well suited for controlling the
positioning of large arrays of solar panels deployed in, and
mounted on, support structure such as that described in co-pending
International Patent Application Serial Number PCT/US06/38185,
filed 28 Sep. 2006 (28 Sep. 2006), and entitled Solar Panel Array
Sun Tracking System, which application is incorporated in its
entirety by reference herein. Such arrays and array tracking
apparatus include panel support structure operatively connected to
drive motors that mechanically pivot and rotate entire rows and
columns of panels in an array simultaneously and in complete
coordination in either or both east/west and/or north/south axes,
as called for by the installation. The tracker controller of the
present invention is designed to provide motor control inputs that
optimally position the panels in an array.
[0012] The solar array tracker controller of the present invention
utilizes a processor programmed with the above-described algorithm
for accurately predicting the location of the sun based on the
date, time of day in hours and minutes, local latitude and local
longitude. The program takes into account the elliptical orbit of
the earth around the sun, which changes slightly over time.
[0013] The controller also includes an interface for a Global
Positioning Sensor (GPS) that provides highly accurate information
on latitude, longitude and global time to the processor.
Additionally, the processor has a digital interface for a highly
precise inclinometer. The inclinometer is mounted along the
rotational axes of the solar energy utilizing device such as a
solar panel array. The inclinometer relays the angle of the solar
panels on the tracker through the digital interface to the
processor. The processor then utilizes the information from the
inclinometer to send optimized positioning information to one or
more drive and adjustment motors, which adjust the position of the
solar array to optimize the angle of incidence to solar rays. Back
and forth east/west movement of the panels is accomplished by
moving the motors forward and backward. The combination of
east/west travel, azimuth and angle of altitude calculated and
positioned by the processor, create an optimized angle of incidence
for the solar energy utilizing device to solar rays.
[0014] As noted, the processor includes networking capability and
Ethernet or Internet capability, and further includes a remote
interface that allows remote acquisition of data and status of the
apparatus on a local area network, a wide area network, or global
network.
[0015] The tracker includes a stand-alone wind sensor and an AC
converter that digitizes wind measurements for input of the sensor
signals to the processor. This weather information is utilized in
severe conditions only, to move the tracker into a neutral
aerodynamic stow position (generally horizontal) at times of high
winds.
[0016] Other novel features which are characteristic of the
invention, as to organization and method of operation, together
with further objects and advantages thereof will be better
understood from the following description considered in connection
with the accompanying drawing, in which preferred embodiments of
the invention are illustrated by way of example. It is to be
expressly understood, however, that the drawing is for illustration
and description only and is not intended as a definition of the
limits of the invention. The various features of novelty which
characterize the invention are pointed out with particularity in
the claims annexed to and forming part of this disclosure. The
invention resides not in any one of these features taken alone, but
rather in the particular combination of all of its structures for
the functions specified.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The invention will be better understood and objects other
than those set forth above will become apparent when consideration
is given to the following detailed description thereof. Such
description makes reference to the annexed drawings wherein:
[0018] FIG. 1 is a block diagrammatic representation of the solar
array tracker controller of the present invention.
DRAWING REFERENCE NUMERALS
[0019] 100 solar array tracker controller
[0020] 110 processor / micro-controller
[0021] 120 operator interface
[0022] 140 GPS interface
[0023] 145 Global Positioning Sensor (GPS)
[0024] 150 digital interface
[0025] 160 inclinometer
[0026] 170 solar energy utilizing device
[0027] 190 initiating relays
[0028] 205 motor
[0029] 210 jack screw or drive shaft
[0030] 220 remote interface
[0031] 230 Internet
[0032] 240 wind sensor
BEST MODE FOR CARRYING OUT THE INVENTION
[0033] Referring to FIG. 1, wherein like reference numerals refer
to like components in the various views, there is illustrated
therein a new and improved solar array tracker controller,
generally denominated 100 herein.
[0034] FIG. 1 illustrates a preferred embodiment of the solar array
tracker controller 100, and shows that the system comprises a
micro-processor/controller 110 having an integral operator
interface 120 with an LCD display and a keypad for entry of local
data. An exemplary system is the Z-World OP6800, which is a
relatively low-cost, C-programmable operator interface and
single-board computer with industrialized I/O, a graphic LCD, and a
keypad. It includes an integrated control, display, and networking
capabilities via Internet/Ethernet or serial communications. This
processor includes memory for storing a program including a
mathematical algorithm that accurately determines the location of
the sun based on local data, such as the date, time of day in hours
and minutes, local latitude and local longitude. The algorithm
takes into account the elliptical orbit of the earth around the sun
which changes slightly over time.
[0035] The processor 110 also includes a GPS interface 140 for a
Global Positioning Sensor (GPS) 145 which provides highly accurate
information on latitude, longitude and global time to the
processor. Additionally, the processor has a digital interface 150
for a tilt sensor or inclinometer 160, such as the Model SCA100T
inclinometer made by VTI Technologies of Vantaa, Finland, or the
Model 0717-4304-99 TrueTilt, dual axis, wide angle, electrolytic
tilt sensor made by The Frederick's Company of Huntingdon Valley,
Pa. The inclinometer 160 is mounted along one or more axes of a
solar energy utilizing device 170, such as a solar panel in a solar
panel array. The inclinometer 160 relays to the processor data
concerning the angle of altitude and azimuth of the solar energy
utilizing device 170 through the digital interface 160 on the
processor. The processor then utilizes the information from the
inclinometer to send optimized positioning information to one or
more drive motors 205, which are operatively linked or connected to
pivoting and rotating apparatus which adjust the position of the
solar energy utilizing device (panels) 170 to optimize the angle of
incidence to solar rays.
[0036] The processor also controls the east/west orientation of the
solar energy utilizing device 170 by initiating relays 190 to the
drive motors 205 to actuate forward and reverse movement of drive
apparatus 210, such as a jack screw or a reciprocating drift shaft.
The combination of east/west travel, azimuth, and angle of altitude
calculated and positioned by the processor creates an optimized
angle of incidence for the solar energy utilizing device to solar
rays.
[0037] The processor also has a remote interface 220 that allows
remote acquisition and transmission of data and status of the via a
global computer network, such as the Internet 230, or in a wide
area network or local area network.
[0038] Further, the tracker controller includes a stand alone wind
sensor 240 which digitizes the wind sensor signals for input into
the processor. In times of potentially damaging high winds, the
signal alerts the processor to send control inputs to the drive
motors to position the array panels in a substantially neutral
aerodynamic stow position (i.e., generally horizontal) This weather
information is utilized to move the tracker into a horizontal stow
position in times of high wind conditions.
[0039] Accordingly, it will be appreciated by those with skill in
the art that the solar panel array tracker controller of the
present invention, in its most essential aspect, comprises a
micro-processor coupled to the drive motors of a solar panel array.
The processor is programmed to calculate the precise location of
the sun relative to the array, and then to control the motors based
on local data, either input by an operator or by a GPS sensor
connected to the processor to place the array panels in an optimal
angle of incidence in relation to the sun's rays. One or more tilt
sensors or inclinometers mounted on a panel or panels provide
information to the processor concerning the current configuration
of the array.
[0040] The foregoing disclosure is sufficient to enable those with
skill in the relevant art to practice the invention without undue
experimentation. The disclosure further provides the best mode of
practicing the invention now contemplated by the inventor.
[0041] While the particular solar tracker array controller
apparatus and method herein shown and disclosed in detail is fully
capable of attaining the objects and providing the advantages
stated herein, it is to be understood that it is merely
illustrative of the presently preferred embodiment of the invention
and that no limitations are intended concerning the detail of
construction or design shown other than as defined in the appended
claims. Accordingly, the proper scope of the present invention
should be determined only by the broadest interpretation of the
appended claims so as to encompass obvious modifications as well as
all relationships equivalent to those illustrated in the drawings
and described in the specification.
* * * * *