CA2139251A1 - Jhvh solar array tracking apparatus - Google Patents

Abstract

This Solar Array Tracking Apparatus comprised of a system of series and parallel wired solar modules, gears, bearings, and pulleys, with a gravity-weight drive arrangement, and an alternating current generator powered from the solar array, is specifically designed to convert solar energy into sufficient electric power to run a home during all daylight hours as a stand alone apparatus with no need to connect into an Electrical Grid or to have supplementary gas or oil generating systems.
Supplementary power can be supplied by a conventional battery bank.

Description

21392~1 DISCLOSURE of Solar Array Trac~ing Apparatus This unique self-contained stand-alone terrestrial two axls photovoltaic tracl~ing apparatus provides a maximum of 115 Volts with 60 amperes of alternating current at a frequency of 60 hertz of continuous and unregulated useful power generation daily during daylight hours within the 58 degree to 75 degree latitude range of Canada and the United States.
Comprised of a system of series and parallel wired solar modules, gears, bearings, and pulleys, with a gravity-weight drive arrangement, and an alternating current generator powered from the solar array, the described unit is specifically designed to convert solar energy into sufficient electric power to run a horne wlth no need to connect lnto an electr lcal ~rld or to have supplementary gas or oil generating systems. Where supplementary power is required a battery ~an~s system can be used.
This apparatus is economical to produce, not difficult to install, is easy to maintain, and is able to withstand the normal extremes in Canadian weather conditions including snow, ice and strong winds.
The invention will be more clearly understood af ter ref erence to the following detailed specifications read in conjunction with the drawings, wherein a clear and complete description of the invention and its usefulness is provided, so as to enable anyone with average s~ill in the basic technological s~ills, to make and use the invention.

-Prior Art Photovoltaic products currently available have a passive powers supply and are very costly. The electrical load determines whether an autonomous system or a hybrid system should be used and defines the size of each component. Commercially available solar electric systems large enough to run a household are very costly as it is necessary to have a great many large series array modules, of different sizes and tilts, expensive inverters.
etc.(with associated high operation and maintenance costs).
Should a special order for a hybrid system be placed by an individual purchaser with an existing solar manufacturing/
installation company, the hybrid system would still of necessity be incorporated into an electric grid, or petroleum base fueled generators, or windmills, and would require costly state-of-the art inverters to convert the numerous array modules to usable a.c. power.
At the present time, standby power systems are used to supply critical loads when photovoltaic systems exhaust their storage capacity. Hybrid systems are designed to routinely use both photovoltaic and auxiliary power systems. Photovoltaics are sometimes used only as a fuel saver for a prime power source, while in other systems a combination of photovoltaic and other power distribution sources are used to charge a common battery banIs "For economic reasons in remote areas with high electricity requirements, it is often advantageous to provide a bacl~-up r~
source of power. Increasingly a hybrid approach is used where, when the photovoltaic ~rray is unable to keep the battery charged, a petroleum powered ~gas, propane, diesel) genset comes on for several hours to bring the battery rapidly up to charge, before switching off again." (ch2pter 1 page 3 from Photovoltaic Systems Design Manual, Energy, Mines and Resources Canada, published by Min~ster of Supply and Services Canada Revised and reprinted June 1991, Catalogue No. M91-7/~8-1989E; ISBN 0-662-17090-3.) ` 21392~1 Until now, limitations of commercially available terrestrial photovoltaic systems include the following: output seldom matches the normal alternating current household load profile;
and the CQStly 2 axis tracl~ing systems will not operate at wind speeas gre~t er than 5Q ~sph.
One axis tracl~ing systems that are normally used for linear concentrating modules and allow the modules to tracl~ the sun from east to west, do not permit the array to tracX the change in elevation of the sun, although in some the tilt angle of the array may be manually adjusted on a seasonal basis.
Two-axis trac}~ing systems are used for modules with a high concentration ratio, and allows the module to remain facing directly at the sun at all times. Most rotating arrays will not operate at wind speeds greater than 50 l~ph.
Fixed arrays cost less to install than tracl~ing arrays and require lower maintenance, but tracl~ing arrays provide more energy for the same module area particularly in clear sunny clir~ates. The direction in which a fixed array faces is almost always due south.
t'Because of the added capital cost of a tracl~er, it can rarely be justified, fixed arrays are almost always used on smaller systems. Also since most of Canada has relatively cloudy weather, fixed arrays have been used for almost all large systems in this country as well." (ibid~
Some larger arrays consist of several identical sections, each independently mounted; in such cases the entire array is called an array field, and each section a sub-array or module panel.
Some arrays include reflectors mounted at an angle adjacent to the module to increase the amount of sunlight onto the module thereby increasing their power output.
A fixed photovoltaic array consists of a number of electrically interconnected photovoltaic modules which safely deliver power to an external device such as a load or power conditioner. Every array will include module interconnect 213~Sl cabling and a mechanical support structure, and may include such items as blocl~ing diodes, bypass diodes, test points, fuses, switches, intermediate junction boxes, reflectors, lightning protection devices, and an electrical grounding system.
This invention provides remote individual residences and mobile homes in Canada and the U.S. with a stand alone solar radiation tracXing apparatus with its own active power supply which produces 115 alternating volts and 60 amps. at a frequency of 60 hert2; thereby eliminating the need for connections to an electrical grid, and/or oil or gas generation to supplement the power system during daylight hours. Where supplementary power is required at night a battery ban1~ is used.
Generally this photovoltaic system is able to meet all household load requirements for daytime operation other than Z2Q
vac.
The night-time power source, the battery ban}~, will operate as close to the aforementioned fixed output, for as efficient as possible night hours operation, and will be fully rechargeable through this inventions' power supply if a standard 120 vac 8.5 ampere battery charger is used.

The bul~ of the information relating to the Prior Art section was derived from material within the combined libraries of the Canadian Solar Industries Association and the Canadian Photovoltaic Industries Association as well as f rom materials and publications of the Government of Canada with particular reference to "Photovoltaic Systems Design Manual", Energy, Mines and Resources Canada, published by Minister of Supply and Services Canada Revised and reprinted June 1991, Catalogue No.
M91-7/48-1989E; ISBN 0-662-17090-3.)

Claims (12)

1. One object of this invention is to provide a unique apparatus which is a self-contained rotating photovoltaic array with a gravity-weight drive arrangement which provides a maximum of constant and regulated 115 volts alternating current with 60 amperes at a frequency of 60 Hertz during normal sunshine hours, and will operate at wind speeds greater than 50 Kph.

2. The purpose of this invention is to provide remote individual residences and mobile homes with a stand alone solar radiation tracking unit with its own unique active power supply; thereby eliminating the need for connections to an electrical grid, and/or oil or gas generation to supplement the power system.
Where supplementary power is required at night a battery bank system can be used.

3. This self-contained photovoltaic power pack includes:
a) a series-parallel array of photovoltaic cells which utilizes sunlight which is converted to electrical power by means of a unique structure upon which the solar array will sit;
b) The unique cell holding solar array table of the solar array tracking apparatus can be adjusted to accommodate monthly changes in the solar position. The surf ace of this box being at an angle which accommodates those parts of the world within the range of 58 degrees to 75 degrees latitude; but which can be modified to accommodate other parts of the world.
c) The unique structure which consists of a unique system of gears, bearings, and pulleys, sits on the ground and is a simple, rigid, wood and steel frame platform with concrete footings for stabilization and support, and the grounding system itself consists of a wire ground and iron or steel rods.
d) a gravity-weight drive arrangement effects rotation of the transducer element;

4. Tracking Device: Daily, the sun crosses the sky from east to west, and climbs and descends from the southern horizon with the progression of seasons. The JHVH Solar Array Tracking Apparatus, using a unique two axis turntable with a gravity weight arrangement steering mechanism, is designed to provide full tracking of the sun allowing for sweeping of the sky in two directions by following the sun's east-west route and it is adjustable in relation to the sun's height (angular distance from the horizon) at a compromise angle.
This unique solar tracking apparatus tracks the sun during all daylight hours each day, thereby, constantly redirecting or imaging the sun's rays directly onto the solar cell array during all daylight hours each day throughout the year.

5. Steering Mechanism: The angle of incident of the solar array is arranged on the table in the desired position with a given angle to the sun; in this case within the 58 degree to 75 degree latitude range to accommodate most of Canada and the United States of America.
For two-axis tracking this invention uses a unique turntable and power drive which includes sisal rope, direction turning gears, pulleys, bearings, and a gravity weight drive mechanism.

6. Gravity Weight Drive Mechanism: Law of gravitation states that all bodies in the universe have a mutual attraction for one another. This attractive force is in direct proportion to product of masses of bodies concerned and varies inversely as square distance between them. Gravitation constant is force exerted by a body with mass of 1 gram upon another body with same mass at a distance of 1 cm. Gravity is that force operating between other bodies and the earth. This force is the cause of a body's having weight; the force is considered to act upon the whole body at a definite point (the center of gravity) within the body. The force of gravity varies slightly in different places, therefore the weight also varies accordingly. Gravity near the earth gives to a downward moving body a uniform acceleration.

The balanced weight drive mechanism 4 is enclosed within the frame of the solar tracking apparatus 5 to minimize disturbance due to air current and other outside influences. It is mounted on a turntable so that it can be brought first under one of the counter-poised spheres, then under the other, and the consequent tilt of the balance.
Two measured masses of formed concrete (one being divided for return-to-start position) are connected by a sisal rope that passes over four pulleys 6; since the inertia to motion (effective mass) depends on the sum of the two masses and the inertia of the pulley, whereas the gravitational pull depends on the difference of the masses, the acceleration is regulated by an attached drive gear 7, detailed diagrams "A" and "B", which moves through a corresponding gear track 8 with stops attached at each end of the gear track.
Two measured concrete spherical masses attached to the ends of connected eye bolts encased into the concrete weights which are suspended by sisal rope at its midpoint. When two large spheres A,B, are brought together each will move together causing the opposite side small sphere to retract from its position and thus the torque will cause the beam with the drive gear to revolve, generated by the pulley gear shaft.

7. Boosting Voltage and Amperage: The solar cells, when illuminated, act like a battery in that they produce electrical voltage and current, increasing the light on a cell increases the power output, which by directing the light onto the array permits a decrease in the number of cells needed for a specified power output; resulting in this invention having the solar array consist of only two solar cell modules.
The amount of current is limited by the amount of light falling on the cells and the sunlight conditions usually encountered is calculable by Air Mass2 (AM2) an illumination of 800 w/m2.
The peak power current changes proportionally to the amount of sunlight, but the voltage drops only slightly with large changes in the light intensity.
As the load resistance increases, causing the voltage output of the cells to increase, the current remains relatively constant until the "knee" of the current-voltage curve is reached (P max=
Vm x lm).
The movement of the electrons within the solar cells of the array that produces the electric current of ultraviolet radiation is done by photons of light of sufficient energy to cause the electrons to jump from the valence bands to a conduction band causing "holes" to exist and the "holes" move when electrons fall into them, creating new "holes". "Holes" from both the valence band and conduction band carry electric current and the number of excited electronic states in any atom is theoretically infinite.
Some of the above mentioned solar cells are gathered into groups and wired in parallel (current building), other cells are strung together and wired in series (voltage building). It is the gathering and stringing of the cells in series which builds up the voltage which is the prime mover of the a.c. generator; then grouping strings of cells in parallel with the use of a solar powered electric generator increases the amperage sufficiently to provide the total power output of this invention.

8. A fuse box is incorporated. (Figure 5 Number 9)

9. Regulators: The output of this solar array is at a predetermined and fixed level of correct alternating voltage in order to ensure a consistent useable alternating current output.

10. Diodes: Blocking diodes 10 are used in series with the array to prevent current from flowing in a reverse direction. These diodes are voltage rated for both maximum forward and reverse -bias voltages (anodic and cathodic). When applying voltage in reverse-bias direction, the voltage must be increased to a much higher value of the diode before the diode crystal will finally break down and conduct reversal voltage.

11. Electric Generator: The windings of the driver electro-magnet in the externally excited A.C. oscillating generator is fed by the voltage and current from the solar array series connected module itself. This generator gives an alternating electromotive force which for uniform apparatus oscillation does not vary with time (daytime).
There are many ways of modulating a dc signal converting it to alternating voltage. The necessary increase of e.m.f. is obtained by an appropriately rated potential transformer.
The initial unidirectional D.C. current reverses each time the generator e.m.f. changes direction. In this simple A.C.
generator, the output from the reed assembly will oscillate between the normally open contacts and the normally closed which provides a steady output.
This apparatus uses a center-tap power transformer, except that its volt-ampere rating is low. The primary of said apparatus is wound for array voltage and its secondary for 115 volts.
This invention's A.C. electric generators' initial induced e.m.f. is small. The direction of the induced e.m.f. is reversed during its course at the center-tapped transformer's primary coil, resulting in alternating voltage.
The method used in this application is the so-called vibrator generator power supply design. An alternating voltage applied to this invention's driver coil 12 causes the reed to oscillate at the same frequency of 120 times per second. The armature reed acts as the common terminal in the single pole double throw relay which alternates the direction of voltage flow through the primary coil of the transformer 11. This induces an alternating voltage (which is also the line frequency) in the secondary coil of the transformer, the resulting output is proportional to the input signal and in phase with the voltage in the driver coil.
Current in the electromagnetic coil produces an electro-magnetic movement which uniformly energizes and de-energize the coil. The oscillation is limited by fixed frequency 13. When applied across a resistance, the alternating e.m.f. gives rise, in accordance with Ohms Law, to an alternating current of the same frequency; and the frequency of electrical supply from this generator is a set 60 full cycles per second (120 oscillations per second).
In combination, an alternating electromotive force (e.m.f.) of this inventions' a.c. generator, there is the impressing unit 15 which is attainable by superposition of the direct current module which is directed by the frequency regulated alternating flow, and being resonant with the predetermined frequency of said device which produces a source of alternating voltage and maximum current of said predetermined frequency.

12. As in accordance with one of Kirchoff's Laws: in any closed circuit, the algebraic sum of the products of the current and resistance of each part of the circuit is equal to the sum of the e.m.f.'s. round it; this law is also true for alternating current if impedance are used in place of resistances.
Such coupling is smoothed through "run" capacitors (not shown) utilized in unpolarized circuits with a steady potential across the capacitors positive and negative plates, whereby the meshing of the two circuits causes both the e.m.f. and the current to be in phase with the regulatory circuit of C1.
The inventions main supply circuit (C2) is changed by making a change in the current through the principle of super position. This change in the overall current (inclusive of the voltage branch) is equal to that which would be produced through conventional power supplies since e.m.f. is equalized by being added in series restricted from reverse flow by diodes 10.
The e.m.f. placed in the voltage circuit 1 produces the same voltage at the capacitors for circuit 2, then the equal e.m.f. is meshed into circuit 2 producing in the main supply capacitors a resonant current as though the impressed e.m.f. in circuit 1 is the prime mover.