WO2009038307A2

WO2009038307A2 - Generating apparatus using a high concentrator photovoltaic module

Info

Publication number: WO2009038307A2
Application number: PCT/KR2008/005337
Authority: WO
Inventors: Dae Ho Seo; Seung Yeon Jung
Original assignee: Dae Ho Seo; Seung Yeon Jung; Jang Kyung Koo
Priority date: 2007-09-20
Filing date: 2008-09-10
Publication date: 2009-03-26
Also published as: WO2009038307A3

Abstract

Provided is a photovoltaic power-generating apparatus configured to maximize power- generating efficiency thereof. The photovoltaic power-generating apparatus includes a lens unit focusing incident light of the sun, a light-collecting unit collecting light of the sun, except for the light focused by the lens unit, in high concentration, a photovoltaic unit coupled to a lower end of the light-collecting unit and converting a solar energy of both the focused light and the collected light into an electrical energy and outputting the electrical energy, and a housing storing the focusing unit, the light-collecting unit, and the photovoltaic unit.

Description

GENERATING APPARATUS USING A HIGH CONCENTRATOR PHOTOVOLTAIC MODULE

Technical Field

[1] The present invention relates to a photovoltaic power- generating apparatus, and more particularly, to a photovoltaic power-generating apparatus increasing energy concentration of the sun's light incident to photovoltaic cells to maximize power- generating efficiency thereof. Background Art

[2] Photovoltaic modules, including a plurality of arranged PN semiconductor devices attached to each other, directly convert a solar energy into an electrical energy. The photovoltaic modules are disposed on a plane to realize a photovoltaic power- generating apparatus.

[3] Such photovoltaic power-generating apparatuses using non-polluting and unlimited solar energy, do not require an additional fuel and are considered as an eco-friendly apparatus without air pollution and wastes. Also, the photovoltaic power-generating apparatuses are semiconductor devices that do not cause mechanical vibration and noise.

[4] However, in the related art photovoltaic power- generating apparatuses, photovoltaic modules are just arranged in a grid pattern on a plane to convert an incident solar energy into an electrical energy. In this case, it is difficult to collect the solar energy in high concentration.

[5] Also, a tracking apparatus applied to the photovoltaic power-generating apparatuses, i.e., a tracker sets an azimuth using a supporting shaft having one end fixed to a ground, and the other end connected to a center of a rear surface of a photovoltaic module, and the tracker sets an altitude using a cylinder and a piston rod, thus the tracker has mechanical limitations including an unstable structure and a tracking deviation during the setting of the azimuth and the altitude. Particularly, since there is a limitation in rotation for the altitude of the photovoltaic module, it is difficult to rotate the photovoltaic module such that the photovoltaic module faces a ground to deal with weather change including a storm and a hailstone. Disclosure of Invention

Technical Problem

[6] An object of the present invention is to provide a photovoltaic power-generating apparatus collecting incident solar energy in high density to improve energy conversion efficiency. [7] Another object of the present invention is to provide a photovoltaic power-generating apparatus configured to be protected from an external force caused by environmental change and weather change. Technical Solution

[8] To achieve the objects of the present invention, there is provided a photovoltaic power-generating apparatus including: a focusing unit including a plurality of separated lenses and focusing incident light of the sun in respective separated regions; a light-collecting unit collecting light of the sun, except for the light focused by the focusing unit, in high concentration; a photovoltaic unit coupled to a lower end of the light-collecting unit and converting energy of the light, collected by the light-collecting unit and focused by the focusing unit, into an electrical energy and outputting the electrical energy; and a housing storing the focusing unit, the light-collecting unit, and the photovoltaic unit.

[9] According to another aspect of the present invention, there is provided a photovoltaic power-generating apparatus including: a focusing unit including a plurality of separated lenses and focusing incident light of the sun in respective separated regions; a light-collecting unit collecting light of the sun, except for the light focused by the focusing unit, in high concentration; a photovoltaic unit coupled to a lower end of the light-collecting unit and converting energy of the light, collected by the light-collecting unit and focused by the focusing unit, into an electrical energy and outputting the electrical energy; a housing storing the focusing unit, the light-collecting unit, and the photovoltaic unit; a supporting frame including a couple of posts rotatably supporting a side surface of the housing, and a supporting bar connecting the posts to each other to support the posts; an altitude-adjusting unit provided to any one of the posts to rotate the housing on a vertical plane; and an azimuth-adjusting unit provided to the supporting bar to rotate the supporting frame on a horizontal plane.

Advantageous Effects

[10] According to the present invention, incident light of the sun can be continuously collected and focused to the photovoltaic cell, and the sun's light can be collected in high density to improve energy conversion efficiency. [11] Also, the photovoltaic power-generating module having a great load is horizontally supported at two points to improve wind pressure-resistant performance, and a

360-degree rotation performance prevents the photovoltaic power-generating module from an external force. [12] Also, the structure of both the azimuth adjusting unit and the altitude adjusting unit is simple to reduce manufacturing costs and rotation load, and the structure, where the gears engage with each other, can reduce rotation deviation. Brief Description of the Drawings

[13] FIG. 1 is an exploded perspective view illustrating a photovoltaic power- generating apparatus according to an embodiment of the present invention.

[14] FIG. 2 is a cross-sectional view illustrating a photovoltaic power-generating module according to an embodiment of the present invention.

[15] FIG. 3 is a perspective view illustrating an altitude-adjusting unit according to an embodiment of the present invention.

[16] FIG. 4 is a perspective view illustrating an azimuth-adjusting unit according to an embodiment of the present invention.

[17] FIG. 5 is a cross-sectional view illustrating a focusing unit according to an embodiment of the present invention.

[18] FIG. 6 is a cross-sectional view illustrating a focusing unit according to another embodiment of the present invention.

[19] FIG. 7 is a cross-sectional view illustrating a focusing unit according to further another embodiment of the present invention.

[20] FIG. 8 is an exploded perspective view illustrating a supporting module and driving modules according to an embodiment of the present invention.

[21] FIG. 9 is a perspective view illustrating an operation of an altitude-adjusting unit according to an embodiment of the present invention.

[22] FIG. 10 is a perspective view illustrating an operation of an azimuth-adjusting unit according to an embodiment of the present invention. Best Mode for Carrying Out the Invention

[23] Hereinafter, specific embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[24] FIG. 1 is an exploded perspective view illustrating a photovoltaic power-generating apparatus according to an embodiment of the present invention. FIG. 2 is a cross- sectional view illustrating a photovoltaic power-generating module. FIG. 3 is a perspective view illustrating an altitude-adjusting unit. FIG. 4 is a perspective view illustrating an azimuth-adjusting unit.

[25] The photovoltaic power-generating apparatus includes the photovoltaic power- generating module 100, a supporting frame 200, and driving modules 300 and 400.

[26] The photovoltaic power- generating module 100 includes a focusing unit 130, a supporting unit 140, light-collecting units 156, photovoltaic units 150, and a housing 160 storing them. The focusing unit 130 focuses the sun's light on photovoltaic cells. The supporting unit 140 reflects dispersed light of the sun. The light-collecting unit 150 collects the dispersed light of the sun. The photovoltaic unit 150 converts a solar energy into an electrical energy and outputs the electrical energy. [27] The supporting frame 200 supports the photovoltaic power-generating module 100 at two points in a horizontal position, to effectively react to external impact including wind pressure and to allow an azimuth in a horizontal plane and an altitude in a vertical plane to be freely adjusted through 360 degrees.

[28] The driving modules 300 and 400 include an altitude adjusting unit 300 and an azimuth adjusting unit 400, and have a rotatable simple structure where a worm wheel gear is engaged with a worm gear, to reduce a rotation deviation.

[29] 1. PHOTOVOLTAIC POWER-GENERATING MODULE

[30] 1.1. Structure of Photovoltaic Power-Generating Module

[31] Housing

[32] Referring to FIG. 1, the housing 160, having a box shape with an open upper portion, includes a plurality of brackets 164 and 166. The brackets 164 are installed to an inner surface of the housing 160 to fix the supporting unit 140, and the brackets 166 are installed to a bottom of the housing 160 to fix a heat sink plate 152 or a cell receiver.

[33] A plurality of heat sink fins may be installed to an outer surface of the housing 160 to quickly and efficiently release inner heat to the outside. The housing 160 may be formed of aluminum that is a light weight and high strength metal material.

[34] Also, a fixing frame 110 may be coupled to an upper end of the open housing 160 to press and fix an edge of the focusing unit 130 or a protection panel 120.

[35] Focusing Unit

[36] FIG. 5 is a cross-sectional view illustrating the focusing unit 130 according to one embodiment of the present invention.

[37] Referring to FIG. 5, the focusing unit 130 includes a lens frame 132 having a grid pattern, and lenses 134 mounted to respective squares of the lens frame 132.

[38] For example, the lenses 134 may be fresnel lenses, to focus incident light of the sun on the photovoltaic cells of the photovoltaic units 150 in the respective separated squares.

[39] The transparent protection panel 120 is mounted to a front surface of the focusing unit 130, to prevent contamination of the lenses 134 from the ingress of an external foreign object, and to prevent damage of the lenses 134 due to external impact. For example, the protection panel 120 may be formed of a low iron tempered glass, but may be omitted when transmittance is critical. Alternatively, the protection panel 120 may include a poly methyl methacrylate (PMMA) sheet.

[40] FIG. 6 is a cross-sectional view illustrating a focusing unit 1130 according to another embodiment of the present invention.

[41] According to this embodiment, ribs 1134a are disposed along edges of lenses 1134, and a transparent adhesive 1132 is interposed between the adjacent ribs 1134a to achieve adhesion, additional rivets 1133 reinforces coupling of the ribs 1134a. Also, the adjacent ribs 1134a are connected using heat melting including laser welding to prevent the ingress of moisture there between.

[42] Alternatively, the adhesion may be achieved by directly interposing the adhesive

1132 between side surfaces of the lenses 1134 without the ribs 1134a.

[43] Also, a water-repellent coating may be performed to protect surfaces of the lenses

1134 from scratching, reduce reflectance of incident light, increase light transmittance, and prevent fogging of the lenses 1134. The water-repellent coating may be directly performed on the surfaces of the lenses 1134, or on a protection sheet 1120 of a PMMA material. The water-repellent coating may include a spray method or a spin- coating method.

[44] FIG. 7 is a cross-sectional view illustrating a focusing unit 1140 according to further another embodiment of the present invention.

[45] According to this embodiment, side surfaces of respective lenses 1144 are heat- melted to form bonding portions 1142, so that a single lens plate is obtained. For example, while a heat source passed between the side surfaces of the lenses 1144 to melt the side surfaces, the side surfaces are pressed against each other to achieve melted bonding, and then parts of the bonding portions 1142 protruding out of outer surfaces and inner surfaces are grinded to be flush with the lenses 1144.

[46] As the previous embodiment, the water-repellent coating may be performed on the focusing unit 1140, and the protection sheet 1120 of a PMMA material may be provided thereto.

[47] Supporting Unit

[48] The supporting unit 140 has a grid pattern corresponding to the grid-type lens frame

132 of the focusing unit 130, and its end is inserted into the brackets 164 installed to the inner surface of the housing 160.

[49] The supporting unit 140 is coupled to the lens frame 132 to support the lens frame

132, and to reflect dispersed light of the sun except for the sun's light focused by the focusing unit 130 to the light-collecting units 156.

[50] Cover Sheet

[51] A cover sheet 142 is provided with openings 143 located at positions corresponding to the light-collecting units 156 that will be described later, and an edge thereof is fixed to the inner surface of the housing 160.

[52] The cover sheet 142, e.g., may include an aluminum sheet and prevents a conducting wire, connecting the cell receiver 154 that will be described later, from being exposed to the sun.

[53] Light-Collecting Unit

[54] The light-collecting units 156 collect the sun's light, that are not focused or that are reflected on the supporting unit 140, into the photovoltaic cells in high concentration. [55] Referring to FIG. 1, the photovoltaic unit 150 has a hopper shape to concentrate the collected light onto the photovoltaic unit 150.

[56] Photovoltaic Unit

[57] The photovoltaic unit 150 converts and outputs a solar energy of both the sun's light focused by the focusing unit 130 and the sun's light collected by the light-collecting unit 156 into an electrical energy.

[58] Referring to an enlarged view A of FIG. 1, the photovoltaic unit 150 includes the cell receiver 154 and the heat sink plate 152. The cell receiver 154 includes the photovoltaic cell (not shown) located within a lower end of the light-collecting unit 156, and a heat sink base. The heat sink plate 152, formed of an aluminum or copper material, is attached to an inner surface of the cell receiver 154 and fixed to a bottom of the housing 160. Here, the bracket 166 fixed to the bottom of the housing 160 fixes the heat sink plate 152, as described above.

[59] In this embodiment, although the fixing to the housing with the interposed heat sink plate 152 is exemplified, the cell receiver may be directly installed to the bottom of the housing 160, without using the heat sink plate 152. Referring to an enlarged view B of FIG. 1, the heat sink base 153 of the cell receiver is provided with tapping screw 151, and is directly attached to the bottom of the housing 160 with a heat sink pad 157 disposed between an inner surface of the heat sink base 153 and the housing 160, and then screws are inserted from an outer surface of the housing 160 into the tapping screw 151. This structure is adapted to emit heat more quickly from the photovoltaic cells to the outside.

[60] 1.2 Operation of Photovoltaic Power-Generating Module

[61] The sun's light incident to the focusing unit 130 are focused on the photovoltaic cells of the photovoltaic units 150 by the fresnel lenses 134 including aspherical plates.

[62] Light of the sun except for the light passing through the lenses 134 reflects on the supporting unit 140 and then travels to the light-collecting unit 156.

[63] The light-collecting units 156 collect the sun's light that is not focused or that is reflected on the supporting unit 140 in high concentration.

[64] Then, the photovoltaic cells of the photovoltaic units 150 convert the solar energy of the focused and the collected light into the electrical energy and output the electrical energy.

[65] 2. SUPPORTING FRAME

[66] FIG. 8 is an exploded perspective view illustrating a supporting module and the driving modules.

[67] The supporting frame 200 has a Y-shape to support the housing 160 at two points in a horizontal position, thereby improving wind pressure resistance, and allowing the housing 160 to rotate through 360 degrees. [68] Referring to FIG. 8, the supporting frame 200 includes a couple of posts 220 and 222 rotatably supporting side surfaces of the housing 160, and a supporting bar 210 connecting and supporting the posts 220 and 222. The respective posts 220 and 222 may be connected to the supporting bar 210 through connecting brackets 211 and 213.

[69] The posts 220 and 222 include shaft holes 224 and 223 and a gear hole 226 as described below. A rotation shaft 310 and a fixed shaft 390 of the altitude-adjusting unit 300 are inserted into the shaft holes 224 and 223, respectively. The gear hole 226 exposes a worm wheel gear 320 to the outside.

[70] Also, the supporting bar 210 includes a shaft hole 212 to which a rotation shaft 430 of the azimuth-adjusting unit 400 is inserted.

[71] 3. DRIVING MODULES

[72] 3.1 Structure of Driving Modules

[73] Altitude- Adjusting Unit

[74] Referring to FIG. 8, the altitude-adjusting unit 300 includes the rotation shaft 310, the worm wheel gear 320, motor cases 330 and 350, a worm gear 341, and a driving motor 340 driving the worm gear 341. The rotation shaft 310 penetrates through the post 222 to fix its end to the side surface of the housing 160. The worm wheel gear 320 is disposed inside the post 222 and fitted and fixed on the rotation shaft 310. The motor cases 330 and 350 attached to the post 222 in a perpendicular direction to a penetrating direction of the rotation shaft 310. The worm gear 341 is stored and fixed in the motor cases 330 and 350 and engaged with the worm wheel gear 320.

[75] A cap 302 is fitted on the other end of the rotation shaft 310 to prevent water from entering into the rotation shaft 310, and a worm wheel gear bracket 322, coupled with the worm wheel gear 320, coupled to the rotation shaft 310 through a bolt 321. Also, respective polyacetal (POM) bearings 324 and 326 contact the worm wheel gear 320 and the worm wheel gear bracket 322 to improve a rotation performance. The worm wheel gear 320, the worm wheel gear bracket 322, and the POM bearings 324 and 326 are disposed within the post 222.

[76] POM bearings 370 and 372 are coupled outside and inside of the housing 160, respectively. The POM bearing 370 is coupled with the rotation shaft 310 through a bolt 371 such that the housing 160 is coupled with the rotation shaft 310.

[77] Also, a motor bracket 342, seals 332, 352 and 362, and a cover 360 covering the exposed worm wheel gear 320 are provided.

[78] Meanwhile, the fixed shaft 390 is inserted into the post 220 and fixed through a bolt

391, and POM bearings 380 and 382 coupled with each other inside and outside of the housing 160 are fitted on one end of the fixed shaft 390 to support another side surface of the housing 160. A cap 392 is fitted on the fixed shaft 390 to prevent water from entering into the fixed shaft 390. [79] Azimuth- Adjusting Unit

[80] The azimuth-adjusting unit 400 includes a case 424, a bush bearing 406, a worm wheel gear 420, the rotation shaft 430, a worm gear 413, and a driving motor 410 driving the worm gear 413. The case 424 is fixed to the supporting bar 210. One end of the bush bearing 406 is caught and fixed to a bottom of a case 404, and another end thereof protrudes out of the case 404. The worm wheel gear 420 is fixed to a top of the bush bearing 406. One end of the rotation shaft 430 is fixed to the supporting bar 210 through a bolt 432, and the other end thereof penetrates through the bush bearing 406 and fixed through a slip ring 405. The worm gear 413 is stored and fixed in a motor bracket 412 that is fixed to the supporting bar 210 and that is engaged with the worm wheel gear 420.

[81] The case 424 includes a recess 425 storing the supporting bar 210, and a bottom of the recess 425 is provided with an opening through which the rotation shaft 430 penetrates. The motor bracket 412 is coupled to the supporting bar 210 through the opening. The motor bracket 412 and the driving motor 410 are disposed within the removably coupled cases 404 and 424.

[82] A cap 431 is fitted on one end of the rotation shaft 430 to prevent the ingress of water into the rotation shaft 430, and a POM bearing 422 is fixed to an inner top of the case 424 to improve rotation of the worm wheel gear 420. A cover 402 is coupled to the case 404.

[83] Also, the case 424 includes a printed circuit board 426 in the inner top thereof. A controller (not shown) and a memory, storing data, are mounted to the printed circuit board 426. The controller controls the driving motor 340 of the altitude-adjusting unit 300 and the driving motor 410 of the azimuth-adjusting unit 400.

[84] The bush bearing 406 exposed out of the case 404 is fixed to, e.g., the supporting post 600 fixed to a ground through a member including a bolt, as illustrated in FIG. 2. For example, a moisture prevention member 610 including a rubber material is disposed within the supporting post 600 to prevent the ingress of moisture from a ground into the bush bearing 406.

[85] 3.2 Operation of Driving Modules

[86] The memory, mounted to the printed circuit bard 426, stores a reference information including an information about an altitude and an azimuth of the sun according to previous date and time.

[87] The controller detects the maximum output of the driving module and simultaneously compares the stored reference information with current altitude and azimuth to calculate a deviation, and then disposes the photovoltaic power- generating module 100 at an altitude and an azimuth corresponding to the reference information based on the calculated deviation. [88] Referring to FIG. 9, operation of the altitude-adjusting unit will now be described.

[89] The controller transmits a control signal to the driving motor 340, and then the driving motor 340 is rotated according to an angle based on the control signal, and thus the worm gear 341 coupled to the driving motor 340 through a shaft is rotated.

[90] Also, rotation of the rotation shaft 310, on which the worm wheel gear 320 engaging with the worm gear 341 is firmly fitted, rotates the housing 160 coupled to one end of the rotation shaft 310.

[91] At this point, the fixed shaft 390, coupled to the housing 160 on the opposite side of the housing 160, supports the housing 160 to improve the rotation of the housing 160.

[92] As described above, since the housing is allowed to rotate through 360 degrees, during a storm, a gust and a hailstone due to weather change, and at sunset, the photovoltaic power- generating module 100 is rotated to face a ground, thereby preventing damage of the photovoltaic power-generating module 100.

[93] Referring to FIG. 10, operation of the azimuth-adjusting unit will now be described.

[94] The driving motor 410 is rotated according to control of the controller, and then the worm gear 413, coupled to the driving motor 410 through a shaft, is rotated. At this point, the worm wheel gear 420, engaging with the worm gear 413, is fixed to the bush bearing 406, and the bush bearing 406 is not rotated since the bush bearing 406 is coupled to the supporting post 600 fixed to the ground through its end.

[95] Thus, the motor bracket 412 into which the worm gear 413 is fixed, the cases 404 and 424 coupled with the motor bracket 412, and the supporting bar 210 all rotate, and the rotation of the supporting bar 210 rotates the rotation shaft 430 fixed thereto. At this point, the rotation shaft 430 is enough long to smoothly rotate while penetrating through the bush bearing 406, thereby stably rotating the supporting bar 210 without shaking of the supporting bar 210 due to the load of both of the photovoltaic power- generating module 100 and the supporting frame 200.

[96] While the present invention has been described in detail, it should be understood that various changes, substitutions and alterations can be made hereto without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

[1] A photovoltaic power- generating apparatus comprising: a focusing unit including a plurality of separated lenses and focusing incident light of the sun in respective separated regions; a light-collecting unit collecting light of the sun, except for the light focused by the focusing unit, in high concentration; a photovoltaic unit coupled to a lower end of the light-collecting unit and converting energy of the light, collected by the light-collecting unit and focused by the focusing unit, into an electrical energy and outputting the electrical energy; and a housing storing the focusing unit, the light-collecting unit, and the photovoltaic unit.

[2] The apparatus of claim 1, further comprising a supporting unit supporting the focusing unit and reflecting the light of the sun, except for the light focused by the focusing unit, to the light-collecting unit.

[3] The apparatus of claim 1, wherein the focusing unit comprises a grid- type lens frame, and the lenses are fixed to respective squares of the lens frame.

[4] The apparatus of claim 1, wherein the lenses comprise ribs along edges thereof, and the lens unit comprises a lens plate, and the lens plate is formed by interposing an adhesive between the ribs of the adjacent lenses and by coupling the ribs through a member including a rivet.

[5] The apparatus of claim 1, wherein the focusing unit comprises a lens plate formed by melting and bonding adjacent side surfaces of the lenses using heat.

[6] The apparatus of claim 1, wherein the focusing unit comprises a lens plate integrated by interposing an adhesive between adjacent side surfaces of the lenses.

[7] The apparatus of any one of claims 4 through 6, wherein the lens plate comprises a water-repellent film or a water-repellent coating, and the water-repellent film or the water-repellent coating is adhered to a front surface of the lens plate.

[8] The apparatus of any one of claims 4 through 6, wherein the lens plate comprises a poly methyl methacrylate (PMMA) sheet adhered to a front surface thereof.

[9] The apparatus of claim 2, wherein the supporting unit having a grid pattern is fixed to an inner surface of the housing, and comprises a cover sheet in a lower end of the supporting unit, and the cover sheet includes an opening exposing the light-collecting unit.

[10] The apparatus of claim 1, wherein the photovoltaic unit comprises: a cell receiver including a heat sink base and a photovoltaic cell disposed inside the lower end of the light-collecting unit; and a heat sink plate attached to an inner surface of the cell receiver and fixed to a bottom of the housing.

[11] The apparatus of claim 1, wherein the photovoltaic unit comprises: a photovoltaic cell disposed inside the lower end of the light-collecting unit; and a heat sink base supporting the photovoltaic cell and fixed to a bottom of the housing.

[12] The apparatus of claim 2, wherein the housing comprises a plurality of heat sink fins on an outer surface thereof.

[13] The apparatus of claim 1, wherein the light-collecting unit comprises a hopper shape decreasing in size toward the photovoltaic unit.

[14] A photovoltaic power-generating apparatus comprising: a focusing unit including a plurality of separated lenses and focusing incident light of the sun in respective separated regions; a light-collecting unit collecting light of the sun, except for the light focused by the focusing unit, in high concentration; a photovoltaic unit coupled to a lower end of the light-collecting unit and converting energy of the light, collected by the light-collecting unit and focused by the focusing unit, into an electrical energy and outputting the electrical energy; a housing storing the focusing unit, the light-collecting unit, and the photovoltaic unit; a supporting frame including a couple of posts rotatably supporting a side surface of the housing, and a supporting bar connecting the posts to each other to support the posts; an altitude-adjusting unit provided to any one of the posts to rotate the housing on a vertical plane; and an azimuth-adjusting unit provided to the supporting bar to rotate the supporting frame on a horizontal plane.

[15] The apparatus of claim 14, wherein the altitude-adjusting unit comprises: a rotation shaft penetrating through the post to fix one end thereof to the side surface of the housing; a worm wheel gear disposed inside the post and fitted and fixed on the rotation shaft; a motor case attached to the post in a perpendicular direction to a direction where the rotation shaft penetrates; a worm gear stored and fixed in the motor case and engaged with the worm wheel gear; and a driving motor driving the worm gear.

[16] The apparatus of claim 14, wherein the azimuth-adjusting unit comprises: a case fixed to the supporting bar; a bush bearing having one end caught and fixed to a bottom of the case, and the other end protruding out of the case; a worm wheel gear fixed to a top of the bush bearing; a rotation shaft having one end fixed to the supporting bar, and the other end penetrating through the bush bearing and fixed through a slip ring; a worm gear stored and fixed in a motor bracket fixed to the supporting bar, the worm gear being engaged with the worm wheel gear; and a driving motor driving the worm gear.

[17] The apparatus of claim 16, wherein the case includes a printed circuit board in an inner top thereof, and the printed circuit board includes a controller mounted thereto, and the controller is configured to control driving of both a driving motor of the altitude-adjusting unit and the driving motor of the azimuth- adjusting unit.

[18] The apparatus of claim 14, further comprising a supporting post fixed to a ground to support the azimuth-supporting unit, wherein the supporting post includes a moisture prevention member therein.

[19] The apparatus of claim 1, wherein the lens comprises a fresnel lens.

[20] The apparatus of claim 1, wherein the focusing unit comprises a transparent protection panel stacked on a front surface thereof, and an edge of the protection panel is pressed and fixed by a fixing frame coupled to an upper end of the housing.

[21] A photovoltaic power- generating apparatus comprising: a lens unit focusing incident light of the sun; a light-collecting unit collecting light of the sun, except for the light focused by the lens unit, in high concentration; a photovoltaic unit coupled to a lower end of the light-collecting unit and converting a solar energy of both the focused light and the collected light into an electrical energy and outputting the electrical energy; and a housing storing the focusing unit, the light-collecting unit, and the photovoltaic unit.