Sun-tracking power generating apparatus

A solar-tracking power generating apparatus includes a plurality of sensing units having a directional light-extraction member each, a plurality of solar batteries associated with a light-gathering device each, and a solar trajectory simulation unit. Therefore, the solar-tracking power generating apparatus enables more accurate tracking of solar position and focusing of more sunlight on the solar batteries, so that the solar batteries could absorb more sunlight and convert the same into an increased amount of electric power.

FIELD OF THE INVENTION

The present invention relates to a solar-tracking power generating apparatus, and more particularly to a solar-tracking power generating apparatus that includes a plurality of sensing units and solar batteries with improved light-extraction ability, and a solar trajectory simulation unit.

BACKGROUND OF THE INVENTION

Considering the threatening depletion of petrochemical fuels available on the earth, other types of energy sources, such as solar power generation, wind power generation, and water power generation, have been positively exploited by people to replace the petrochemical fuels. In the case of solar power generation, there is included a solar collector panel, which is oriented to the sun for one or more solar batteries to absorb sunlight and convert the same into electric energy. For the solar collector panel to always face toward the sun, a solar-tracking apparatus is additionally mounted to the solar collector panel. A conventional solar-tracking apparatus mainly uses photosensitive resistors to track sunlight. However, the photosensitive resistors have relatively large sensing error, and the conventional solar-tracking apparatus fails to distinguish the sunlight from other light sources and detect the solar position at dawn.

It is therefore important and tried by the inventor to develop a solar-tracking power generating apparatus that enables more accurate tracking of solar position and focusing of more sunlight on solar batteries, so that the solar batteries could absorb more sunlight and convert the same into increased amount of electric power.

SUMMARY OF THE INVENTION

A primary object of the present invention is to provide a solar-tracking power generating apparatus that includes a plurality of sensing units and solar batteries with improved light-extraction ability and a solar trajectory simulation unit to thereby enable high accuracy in light extraction by the sensing units, and accordingly, more accurate tracking of solar position and focusing of more sunlight on the solar batteries, so that the solar batteries could absorb more sunlight and convert the same into increased amount of electric power.

To achieve the above and other objects, the solar-tracking power generating apparatus according to the present invention includes a solar-tracking unit, a transmission unit, and a control unit. The solar-tracking unit includes a disc being provided on an upper side with an even number of at least two pairs of sensing units and a plurality of solar batteries. The two sensing units in each pair are located in a straight line to be diametrically opposite to each other, such that all the straight lines containing the pairs of sensing units intersect with one another at a center of the disc to equally divide the 360-degree central angle of the disc, and the two sensing units in each pair are equally distant from the center of the disc. Moreover, each of the sensing units includes a solar battery sensor or a photosensitive diode sensor. The transmission unit is connected at an upper end to a lower side of the disc and at a lower end to a base. The control unit receives via a sunlight sensing circuit a signal produced by the solar-tracking unit, and controls the transmission unit via a transmission unit circuit to thereby change a solar-tracking angle of the solar-tracking unit.

With the above arrangements, the solar-tracking power generating apparatus could more accurately track the solar position and focus more sunlight on the solar batteries, so that the solar batteries could absorb more sunlight and convert the same into increased amount of electric power.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Please refer toFIG. 1that is a conceptual view of a sun-tracking power generating apparatus according to a preferred embodiment of the present invention. As shown, the sun-tracking power generating apparatus of the present invention includes a sun-tracking unit1, a transmission unit2, a control unit4, a solar trajectory simulation unit7, and an input unit8.

The solar-tracking unit1includes a disc11being provided on an upper side with two pairs of sensing units12and a plurality of solar batteries13. The two sensing units12in each pair are diametrically opposite to each other, such that two straight lines containing the two pairs of sensing units12perpendicularly intersect with each other at a center of the disc11to equally divide the 360-degree central angle of the disc11, and the two sensing units12in each pair are equally distant from the center of the disc11. Each of the sensing units12includes a solar battery sensor (or a photosensitive diode sensor)121. The use of a solar battery as a sensor advantageously saves a lot of power cost.

The transmission unit2is connected at an upper end to a lower side of the disc11and at a lower end to a base3.

The control unit4includes an 89C51 chip41, which is a control chip for receiving via a sunlight sensing circuit5a signal produced by the solar-tracking unit1, and controlling the transmission unit2via a transmission unit circuit6to thereby change a solar-tracking angle of the solar-tracking unit1.

The solar trajectory simulation unit7includes a field programmable gate array (FPGA)71, a digital signal processor (DSP)72, and a memory73. The FPGA71is electrically connected to the 89C51 chip41while the DSP72and the memory73are electrically connected to the FPGA71to simulate solar trajectories.

The input unit8includes a global positioning system (GPS)81or a keyboard82. A current position of the solar-tracking power generating apparatus is input at the GPS81/keyboard82and sent to the 89C51 chip41, and the input data is shown on a display9electrically connected to the 89C51 chip41.

When the solar-tracking power generating apparatus of the present invention is enabled, solar energy absorbed by each of two solar battery sensors (or two photosensitive diode sensors)121in a first pair of sensing units12oriented to a first direction is converted into voltage (or current) signals. The voltage (or current) signals are sent to the 89C51 chip41via the sunlight sensing circuit5. When the 89C51 chip41determines the voltage (or current) signals from the two solar battery sensors (or a photosensitive diode sensors)121in the first pair of sensing units12are different from each other, the 89C51 chip41will control the transmission unit2via the transmission unit circuit6, so as to change the solar-tracking angle of the solar-tracking unit1in the first direction until the voltage (or current) signals from the two solar battery sensors (or a photosensitive diode sensors)121in the first pair are the same. The solar-tracking angle of the solar-tracking unit1in a second direction perpendicular to the first direction is adjusted in the same principle and procedures as that for adjusting the solar-tracking angle in the first direction, so that the solar-tracking unit1is finally accurately oriented toward the sun, enabling the solar batteries13to absorb the largest possible amount of sunlight.

The solar trajectory simulation unit7is mainly used to assist the solar-tracking power generating apparatus in tracking solar trajectories. When the current position of the solar-tracking power generating apparatus is input at the GPS81/keyboard82and sent to the 89C51 chip41, the 89C51 chip41further sends the position data to the memory73of the solar trajectory simulation unit7. The FPGA71will then conduct logic operation according to the position data stored on the memory73. Meanwhile, the DSP72will assist in and speed up the operation conducted by the FPGA71. Solar trajectories obtained from the logic operation are sent back to the 89C51 chip41to assist in the adjustment of the solar-tracking angle of the solar-tracking unit1. At dawn before the sun appears, the solar trajectory simulation unit7may predict the position at where the sun first appears, so that the solar-tracking unit1may be adjusted in advance to that position and prepared for subsequent solar tracking. Moreover, when there is any other light source during the course of solar tracking by the solar-tracking power generating apparatus, the solar trajectory simulation unit7may also function to assist the solar-tracking power generating apparatus in tracking correct sunlight.

FIG. 2schematically shows a light-gathering device adopted in the preferred embodiment of the present invention. As shown, each of the solar batteries13is further provided with a light-gathering lens132, a cylindrical member133, and an externally threaded rotatable seat131. The solar battery13, the rotatable seat131, the light-gathering lens132, and the cylindrical member133together constitute a light-gathering device for the present invention. The rotatable seat131is made of an aluminum material for upward screwing to the disc11, which is also made of an aluminum material, and the solar battery13is mounted on the rotatable seat131. The cylindrical member133has a lower end connected to the upper side of the disc11to enclose the solar battery13on the rotatable seat131, and an upper end having the light-gathering lens132mounted thereto. By screwing the externally threaded rotatable seat131into the disc11by different depths, the solar battery13mounted thereon may be adjusted to an optimal height for gathering light, so as to achieve the best power generation efficiency.

FIG. 3schematically shows the sensing units12and the light-gathering devices adopted in the preferred embodiment of the present invention. As shown, each of the sensing units12includes, in addition to the solar battery sensor (or the photosensitive diode sensor)121, a directional light-extraction member125. The light-extraction member125has a beveled upper open end1251, and a lower end connected to the upper side of the disc11to thereby enclose the solar battery sensor (or the photosensitive diode sensor)121therein. It is noted the beveled upper open ends1251of the directional light-extraction members125of the two sensing units12in each pair are faced away from each other. When the difference between the sensed voltage (or current) signals from the solar battery sensors (or the photosensitive diode sensors)121of the two sensing units12in each pair is small, the back-to-back beveled upper open ends1251may advantageously amplify such small difference, or, in other words, the voltage (or current) difference between two sensing units12in the each pair may be more sensitively detected by the solar battery sensors (or the photosensitive diode sensors)121, so that the solar-tracking unit1may be adjusted to a more accurate solar-tracking angle for the solar batteries13to absorb the largest possible amount of sunlight.

FIG. 4schematically shows a first embodiment of the transmission unit2adopted in the present invention. As shown, the transmission unit2in the first embodiment thereof includes a first step motor211, a second step motor221, a semicircular gear21, a support23, and a horizontal gear22. The semicircular gear21is perpendicularly connected at its straight edge to the lower side of the disc11. The support23is pivotally connected at an upper end to one side of the semicircular gear21, and fixedly connected at a lower end to a center of the horizontal gear22. The first step motor211is mounted to the support23to drive a first driving gear212, so that the semicircular gear21is driven by the first driving gear212to turn and thereby change a horizontal angulation of the solar-tracking unit1. The horizontal gear22is rotatably connected at its center to an upper side of the base3, and the second step motor221is located at one side of the base3for driving a second driving gear222to rotate, so that the horizontal gear22is driven by the second driving gear222to rotate and thereby move the solar-tracking unit1to a different angle of circumference.

FIG. 5schematically shows a second embodiment of the transmission unit2adopted in the present invention. As shown, the transmission unit2in the second embodiment thereof includes four driving cylinders24, which may be oil cylinders or air cylinders, and are driven by a pump26to work. The four driving cylinders24are mounted on the base3to equally bear an overall weight of the solar-tracking unit1. Each of the four driving cylinders24includes an extension rod241and a first universal joint242. The extension rod241has a lower end extendably received in the driving cylinder24. The universal joint242interconnects the lower side of the disc11and an upper end of the extension rod241. When the extension rods241are extended from or retracted into the driving cylinders24by different distances, the solar-tracking unit1may be adjusted to a different solar-tracking angle. The transmission unit2in the second embodiment thereof may further include a support25mounted on the base3to support the solar-tracking unit1at the center thereof, so as to bear the weight of the solar-tracking unit1along with the driving cylinders24. The support25includes a supporting column251being connected at a lower end to the base3, and a universal joint252interconnecting the lower side of the disc11and an upper end of the supporting column251.

FIG. 5schematically shows a third embodiment of the transmission unit2adopted in the present invention. As shown, the transmission unit2in the third embodiment thereof includes four driving cylinders24, which may be oil cylinders or air cylinders, and are driven by a pump26to work. The four driving cylinders24are mounted on the base3to equally bear an overall weight of the solar-tracking unit1. Each of the four driving cylinders24includes an extension rod241, a first universal joint242, a link243, and a second universal joint244. The extension rod241has a lower end extendably received in the driving cylinder24. The first universal joint242interconnects an upper end of the extension rod241and a lower end of the link242, and the second universal joint244interconnects the lower side of the disc11and an upper end of the link243. By extending or retracting the extension rods241from or into the driving cylinders24by different distances, and adjusting the links243to different angular positions, the solar-tracking unit1may be adjusted to different solar-tracking angles within a widened range.

The solar-tracking power generating apparatus of the present invention is novel and improved because it includes a plurality of sensing units with improved light-extraction ability and a solar trajectory simulation unit to enable high accuracy in light extraction by the sensing units12, and accordingly, more accurate tracking of solar position and focusing of more sunlight on the solar batteries13, so that the solar batteries13could absorb more sunlight and convert the same into increased amount of electric power. Therefore, the solar-tracking power generating apparatus of the present invention is industrially valuable and practical for use to fully meet current market demands.

The present invention has been described with some preferred embodiments thereof and it is understood these preferred exemplary embodiments are not intended to limit the scope, applicability, or configuration of the invention, and that many changes and modifications in the described embodiments can be carried out without departing from the scope and the spirit of the invention that is intended to be limited only by the appended claims.