KR20140060384A - Concentrated solar cell module - Google Patents

Abstract

A concentrated solar cell module is disclosed. More specifically, disclosed is a concentrated solar cell module comprising: at least one fresnel lens concentrating sunlight; at least one optical fiber cable transferring the concentrated light by reflecting the concentrated light from the fresnel lens; at least one solar cell receiving the light transferred from the optical fiber cable; and a radiating plate to lead the solar cell and to radiate the solar cell.

Description

[0001] CONCENTRATED SOLAR CELL MODULE [0002]

The present invention relates to a light collecting type solar cell module, and more particularly, to a light collecting type solar cell module capable of minimizing optical loss and capable of arranging a solar battery cell more freely.

The light-gathering type solar cell module is a solar cell module that collects sunlight at a high magnification of several hundred times using an optical system such as a lens or a reflector, and then enters a solar cell to generate electricity.

In particular, the III-V compound solar cell can produce power equivalent to a small size of 1/500 to 1/1000 in comparison with the power production capacity of a conventional silicon solar cell. Therefore, the III-V compound solar cell has advantages of high power generation efficiency and low manufacturing cost, and it is expected to be used as a next generation solar cell.

However, in the case of modularizing the silicon-based solar cell and the III-V compound solar cell with a light-converging solar cell, it is necessary to reduce the efficiency of the solar light condensing and the electrical connection between the plurality of solar cells Reduced efficiency is becoming a problem. Therefore, these problems are obstacles to the production of full-scale solar cell modules.

Referring to FIGS. 1 and 2, a problem of efficiency reduction occurring in a conventional light-converging type solar cell module will be described.

1 is a schematic view for explaining a conventional condensing type solar cell module. 2 is a schematic view for explaining a solar cell array in a conventional condensing type solar cell module. 1 and 2, a conventional condensing type solar cell module 100 includes a fresnel lens 10, a rod lens 20, a solar cell 30, and a heat sink 40, .

The Fresnel lens 10 is provided to condense sunlight and is generally described as a lens having a role of gathering light like a convex lens, but reducing the thickness. The reason why the Fresnel lens 10 can play the same role as the convex lens even if the thickness of the Fresnel lens 10 is reduced is that the Fresnel lens 10 is divided into several strips, This is because we have reduced the aberrations. In order to collect the light in one place, it is necessary to reduce the difference in refractive index. The Fresnel lens 10 has many concentric grooves on its surface, and the refractive index is adjusted according to the grooves, so that light can be concentrated in one place.

The rod lens 20 is a lens for emitting light having brightness uniformity on an emission surface even when light having no brightness uniformity is incident on the incident surface. The solar light passing through the Fresnel lens 10 is called a " And is used to cause homogeneous light to be incident upon the battery cell 30 when irradiated.

The solar cell 30 is a semiconductor device that converts light energy directly into electrical energy using a photoelectric effect and is formed of a semiconductor thin film having polarities of (+) and (-), respectively. That is, when light is irradiated to the solar cell 30, electrons and holes are generated inside the solar cell 30, and the charges move to the P and N poles, respectively. Due to this phenomenon, a potential difference is generated between the P pole and the N pole. When the load is connected to the solar cell 30 at this time, current flows. The detailed description of the driving principle of the solar cell 30 can be learned from the known technology, and a detailed description thereof will be omitted here.

The heat dissipation plate 40 is provided for drawing the solar cell 30 to achieve heat dissipation. In FIG. 1, the heat dissipation plate 40 is formed in a plate shape for convenience of explanation.

Hereinafter, the conversion efficiency of the solar cell 30 will be described. The conversion efficiency of the solar cell 30 means the amount of solar energy generated by the solar cell in the solar cell 30 to generate electric energy. For example, . The conventional condensing type solar cell module 100 is configured such that the Fresnel lens 10, the rod lens 20 and the solar cell 30 are formed in series as shown in FIG. 1, It is necessary to transmit two kinds of lenses of the lens 10 and the rod lens 20. Therefore, optical loss of about 20% to 30% is generated in the conventional light-condensing type solar cell module 100.

2, the spacing between the solar cells 31, 32, 33, and 34 can not be arbitrarily adjusted, and the distance between the Fresnel lens 10 and the Fresnel lens 10, As shown in FIG. That is, since the size of the Fresnel lens 10 is generally larger than that of the solar cell units 31, 32, 33 and 34 and the solar cell units 31, 32, 33 and 34 are formed in a serial form, The intervals of the battery cells 31, 32, 33, and 34 can not be arbitrarily narrowed. For this reason, the degree of dispersion of the solar cells 31, 32, 33, and 34 is increased and the electrical resistance is increased by about 15% to 20% due to an increase in resistance as the distance between the solar cells 31, an electrical loss is generated.

Therefore, according to the conventional condensing type solar cell module 100, the optical loss (about 20% to 30%) through the Fresnel lens 10 and the rod lens 20 and the solar loss due to the spacing of the Fresnel lens 10 The light efficiency of the solar cell 30 is about 60% to 70% of that of the solar cell 30 when the light-condensing solar cell module 100 is manufactured due to the electrical loss (about 15% to 20%) generated in the electrical connection between the battery cells 30 (I.e., a cell efficiency of about 40% and a module efficiency of about 28%). The reason why the efficiency of the solar cell 30 and the solar cell module 100 are different is as follows. When the solar cell modules 31, 32, 33, and 34 are attached as the solar cell module 100, When a vacant space is generated between the battery cells 31, 32, 33, and 34 and a line is connected between the neighboring solar cells 31, 32, 33, and 34, power loss also occurs to be.

In general, the efficiency of the solar cell module 100 is generally lower than the efficiency of the solar cell 30. This is because the size of the Fresnel lens 10 is relatively larger than that of the solar cell 30 and the rod lens 20 is formed vertically and serially with the Fresnel lens 10 as described above, The spacing between the solar cells 31, 32, 33, and 34 necessarily results from the fact that they are spaced apart by a certain distance or more.

Accordingly, it is an object of the present invention to provide a light-concentrating solar cell module for minimizing optical loss (light loss) caused when sunlight condensed through a Fresnel lens is transferred to a solar cell.

Another object of the present invention is to provide a light-concentrating solar cell module for minimizing an electrical loss caused by a size and a position of a Fresnel lens as a distance between solar cells increases.

Another object of the present invention is to provide a condensing type solar cell module capable of imparting a degree of freedom to the arrangement of solar cell cells determined according to the size and position of the Fresnel lens.

However, the technical object of the present invention is not limited to the above-mentioned matters, and other objects not mentioned can be clearly understood by those skilled in the art from the following description.

According to an aspect of the present invention, there is provided a light-condensing solar cell module including at least one Fresnel lens for condensing sunlight, a light source for totally reflecting and condensing the light condensed by the Fresnel lens, At least one photovoltaic cell, at least one photovoltaic cell, at least one photovoltaic cable, at least one photovoltaic cell for receiving light transmitted through the optical fiber cable, and a heat sink for drawing the photovoltaic cell and radiating heat to the photovoltaic cell.

Here, the optical fiber cable includes a core portion through which light condensed by the Fresnel lens is transmitted and a cladding portion surrounding the core portion, wherein a diameter of the core portion is 200 占 퐉 or less, and a refractive index difference between the core portion and the cladding portion is 4% . ≪ / RTI >

The solar cell may be formed to have a size equal to or smaller than a cross sectional area of the optical fiber cable, and may be electrically connected to each other. Preferably, the light collecting type solar cell module further includes an auxiliary heat dissipating unit connected to the heat sink.

Further, the arrangement of the Fresnel lens and the arrangement of the solar cell may be arranged at predetermined predetermined positions, respectively.

Meanwhile, it should be noted that the solar cell in the light-collecting solar cell module according to an embodiment of the present invention can be interpreted as a compound solar cell using a III-V compound semiconductor.

The optical fiber cable of the light-condensing type solar cell module according to an embodiment of the present invention may include a set of multimode optical fibers, a set of single mode optical fibers, and an optical fiber formed by mixing a multimode optical fiber and a single mode optical fiber Or a combination thereof.

The details of other embodiments are included in the detailed description and drawings.

The embodiments of the present invention have at least the following effects.

That is, it is possible to provide a light-collecting type solar cell module that minimizes light loss generated in the process of transmitting sunlight condensed through a Fresnel lens to a solar cell.

Also, it is possible to provide a light-collecting type solar cell module that minimizes an interval between solar cells in a light-collecting type solar cell module and minimizes electrical loss caused by a dispersion degree between the cell and the cell.

Further, in constructing the light-convergence type solar cell module, vertical and serial arrangement leading to a Fresnel lens, a rod lens, and a solar cell can be omitted, arrangement of the solar cells can be freely arranged, A light-collecting type solar cell module can be provided.

The effects according to the present invention are not limited by the contents exemplified above, and more various effects are included in the specification.

1 is a schematic view for explaining a conventional condensing type solar cell module.
2 is a schematic view for explaining a solar cell array in a conventional condensing type solar cell module.
3 is a schematic view illustrating a light-collecting type solar cell module according to an embodiment of the present invention.
FIGS. 4 and 5 are cross-sectional views illustrating optical transmission of an optical fiber cable of an optical concentrating solar cell module according to an embodiment of the present invention. FIG.
FIGS. 6 to 9 are cross-sectional views for explaining the difference between the multimode optical fiber and the single mode optical fiber.
10 is a schematic view for explaining a light collecting type solar cell module according to another embodiment of the present invention.
FIGS. 11 to 13 are schematic views for explaining the arrangement of solar cell cells formed according to various embodiments of the present invention. FIG.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention and the manner of achieving them will become apparent with reference to the embodiments described in detail below with reference to the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Is provided to fully convey the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims.

It is to be understood that elements or layers are referred to as being "on " other elements or layers, including both intervening layers or other elements directly on or in between. Like reference numerals refer to like elements throughout the specification.

Although the first, second, etc. are used to describe various components, it goes without saying that these components are not limited by these terms. These terms are used only to distinguish one component from another. Therefore, it goes without saying that the first component mentioned below may be the second component within the technical scope of the present invention.

As used herein, the term solar cell is defined as a minimum unit for generating electricity, and a solar cell module is a module for generating electric power by connecting several solar cells in series and / or in parallel in a large solar cell system Is defined. On the other hand, in the present specification, it is revealed that the solar cell may be a compound solar cell using a III-V compound semiconductor.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

3 is a schematic view illustrating a light-collecting type solar cell module according to an embodiment of the present invention. Referring to FIG. 3, the condensing type solar cell module 200 includes a Fresnel lens 110, an optical fiber cable 150, a solar cell 130, and a heat sink 140.

The Fresnel lens 110 is a structure for condensing sunlight and delivering it to the optical fiber cable 50. The Fresnel lens 110 has a plurality of concentric grooves formed on the surface thereof, and is a lens having a thickness reduced while collecting sunlight like a convex lens. The reason why the Fresnel lens 110 can function as a convex lens even if the thickness of the Fresnel lens 110 is reduced is that the Fresnel lens 110 is divided into several bands, (The yield). In addition, the difference in refractive index must be reduced in order to collect the light in one place, which is achieved by a plurality of concentric grooves formed on the surface of the Fresnel lens 110.

In other words, the Fresnel lens 110 is a convex lens for condensing light. If a large amount of light is desired to be obtained, the focal length becomes short and the thickness becomes thick, so that the weight becomes heavy and the light absorption also increases. Therefore, And is implemented with a lens having a thinner peripheral portion.

The solar cell 130 is configured to convert sunlight energy into electric energy. That is, it is a device that converts light energy into electric energy. The solar cell 130 has a structure different from that of the conventional chemical cell and is also referred to as a 'physical cell'. The solar cell 130 includes two types of semiconductors, a P type semiconductor and an N type semiconductor, .

That is, when light is irradiated to the solar cell 130, electrons and holes are generated inside the solar cell 130, and the generated charges move to the P and N poles. As a result, A potential difference occurs between the N poles. At this time, when a load is connected to the solar cell 130, a current flows, which is also referred to as a photoelectric effect, and the solar cell 130 may refer to a device that generates current using such photoelectric effect .

The heat dissipation plate 140 is provided for drawing heat to the solar cell 130 by drawing the solar cell 130, and is generally provided for emitting heat by using radiation or convection. In other words, when the light-convergence type solar cell module 200 is used, since the light reaching a number of times of incident sunlight is concentrated in one solar cell 130, the temperature inside the solar cell 130 rapidly increases, Which leads to deterioration of efficiency.

Therefore, in the light collecting type solar cell module 200 according to an embodiment of the present invention, the heat dissipating plate 140 should be attached to the lower surface adjacent to the solar cell 130 so as to dissipate heat. As the material of the heat sink 140, for example, aluminum or the like may be used. The heat sink 140 and the solar cell 130 may be attached using a thermally conductive resin or the like. In the light collecting solar cell module 200 according to an embodiment of the present invention, The material to which the battery cell 130 is attached is not limited.

On the other hand, due to the high temperature generated by the sunlight condensed by the Fresnel lens 110, the adhesive force of the thermally conductive resin decreases, and the heat sink 140 adhered to the lower surface easily peels off. In the light collecting type solar cell module 200 according to the embodiment of the present invention, the structure of pulling the solar cell 130 into the heat sink 140 is used, so that the problem of peeling described above can be solved.

The optical fiber cable 150 is a medium for transmitting the light condensed by the Fresnel lens 110 to the solar cell 130. The optical fiber cable 150 outputs the input light by total reflection to output the output light And the solar cell 130 can receive the light. The optical fiber cable 150 may be composed of a set of optical fibers 151. Refer to Figs. 4 and 5 for a more detailed description of the total reflection of the optical fiber cable 150 and the optical fiber cable 150. Fig.

FIGS. 4 and 5 are cross-sectional views illustrating optical transmission of an optical fiber cable of an optical concentrating solar cell module according to an embodiment of the present invention. FIG. Fig. 4 shows a cross section perpendicular to the longitudinal direction of the optical fiber 151, and Fig. 5 shows a cross section along the longitudinal direction of the optical fiber 151. Fig.

The optical fiber cable 150 may be composed of a set of optical fibers 151, as shown in FIGS. The optical fiber 151 is composed of a core 153 and a cladding 152.

The core portion 153 transmits the input light according to the optical wave theory (total reflection), and the cladding portion 152 is formed to surround the core portion 153 to induce total reflection of the input light at the core portion 153 . That is, the input light input to the core unit 153 is totally reflected by using the refractive index difference between the core unit 153 and the cladding unit 152.

The optical fiber 151 can transmit light in the UV (Ultra Violet) to NIR (Near Infra Red) region (light wavelength of about 350 nm to 1,800 nm) depending on the material type and diameter of the core unit 153 that transmits light have.

At this time, as the refractive index difference between the core part 153 and the cladding part 152 is smaller, the transmittable optical wavelength can be limited, which will be described with reference to FIGS. 6 to 9. FIG.

FIGS. 6 to 9 are cross-sectional views for explaining the difference between the multimode optical fiber and the single mode optical fiber. FIGS. 6 and 7 are cross-sectional views of a multi-mode optical fiber 154, and FIGS. 8 and 9 are cross-sectional views of a single-mode optical fiber 157. Referring to FIG.

6 and 7, the multimode optical fiber 154 can transmit light in a multi-wavelength (visible to NIR) region. In the multimode optical fiber 154, the diameter of the core portion 156 is about 200 μm or less, and the refractive index difference between the core portion 156 and the cladding portion 155 is about 4% or less.

Next, referring to FIGS. 8 and 9, the single mode optical fiber 157 can transmit light having a short wavelength. In the single mode optical fiber 157, the diameter of the core portion 159 is about 10 μm or less, and the difference in refractive index between the core portion 159 and the cladding portion 158 is about 1% or less.

The optical fiber 151 used in the light collecting solar cell module 200 according to an embodiment of the present invention can be used for both the single mode optical fiber 154 and the multimode optical fiber 157. However, It is preferable to use a multimode optical fiber 157 capable of transmitting light in a multi-wavelength region.

Therefore, the optical fiber cable 150 used in the light-condensing solar cell module 200 according to an embodiment of the present invention may be a set of multimode optical fibers 157, and may be a solar cell The optical fiber cable 150 may be formed by using the multimode optical fiber 157 and the single mode optical fiber 154 together in consideration of the characteristics of the cell 130.

Since the optical fiber cable 150 used in the light converging solar cell module 200 according to the embodiment of the present invention may have flexibility, the Fresnel lens 110 and the solar cell 130 can be avoided, and the position of the Fresnel lens 110 and the position of the solar cell 130 can be easily changed during use. That is, in the light-collecting solar cell module 200 according to the embodiment of the present invention, the arrangement of the Fresnel lens 110 and the arrangement of the solar cell 130 are determined arbitrarily It is possible to arrange them freely in position.

In addition, the light condensed from one Fresnel lens 110 is transmitted to the corresponding solar cell 130 through the optical fiber cable 150. However, in the condensing type solar cell module according to the embodiment of the present invention, The light source 200 may be configured to transmit the condensed light from one Fresnel lens 110 to a plurality of solar cells (for example 131, 132, 133, 134, 135, 136 in FIGS. It is possible to use the optical fiber cable 150 of the optical fiber cable 150 in a branched manner. Accordingly, the condensing type solar cell module 200 may include a configuration using a multi-branched optical fiber cable formed for this purpose.

Also, in this multi-branching optical fiber cable, the optical fiber included in the multi-branching optical fiber cable may use only one of the two types of multimode optical fiber or single mode optical fiber, or two types of optical fibers may be used in combination, considering the characteristics of the solar cell. .

10 is a schematic view for explaining a light collecting type solar cell module according to another embodiment of the present invention. Referring to FIG. 10, the condensing type solar cell module 300 includes a Fresnel lens 110, an optical fiber cable 150, a solar cell 130, a heat sink 140, and an auxiliary heat sink 260. For convenience of explanation, elements substantially the same as the elements shown in the drawings of FIG. 3 are denoted by the same reference numerals, and redundant description thereof will be omitted.

10, the auxiliary heat dissipating unit 260 may be formed to have a plurality of heat dissipating plates adjacent to the solar cell 130 and connected to the heat dissipating plate 140 and having the same plate shape as the heat dissipating plate 140 Do. In FIG. 10, as one example, the auxiliary heat-radiating portion 260 is formed in a plurality of aluminum heat-radiating plates so that heat is radiated through the air. Further, although not shown in FIG. 10, the auxiliary heat sink 260 may be formed by using various heat dissipating means such as water-cooling type or air-cooling type.

Accordingly, the auxiliary heat sink 260 of the light collecting solar cell module 300 according to another embodiment of the present invention includes all the heat dissipating means for facilitating the heat dissipation of the solar cell 130 in addition to the existing heat sink It should be noted that

Hereinafter, with reference to FIGS. 11 to 13, it will be described that the arrangement of the solar cell in the various embodiments of the present invention can be freely configured.

FIGS. 11 to 13 are schematic views for explaining an arrangement of solar cell cells formed according to various embodiments of the present invention. FIG.

11 to 13, in the light collecting type solar cell module according to various embodiments of the present invention, the arrangement of the solar cells 131, 132, 133, 134, 135, As shown in FIG. That is, even if the solar cells 131, 132, 133, 134, 135, 136 are arranged at arbitrary positions according to the design of the user and they are electrically connected to each other, And accordingly, the arrangement of the solar cells 131, 132, 133, 134, 135, 136 can be freely configured.

It can be seen that the conventional condensing type solar cell module is advantageous in view of the size of the Fresnel lens and the arrangement of the Fresnel lens and the rod lens in series so that the arrangement of the solar cell is inevitably limited (See Figs. 1 and 2).

11, each of the solar cell units 131, 132, 133, 134, 135, and 136 is connected to a solar cell array in a light-collecting solar cell module using a conventional rod lens, As a result, the electrical loss caused by the gap between the solar cells can be reduced.

12, the respective solar cells 131, 132, 133, 134, 135, and 136 are integrated to a size equal to or smaller than the cross sectional area of the optical fiber cable 150, , 134, 135, and 136 may be minimized.

In addition, since it is easy to change the shape and length of the optical fiber cable 150 in the light-collecting type solar cell module according to various embodiments of the present invention, the optical fiber cable 150 may be formed to correspond to each Fresnel lens 110 It is also possible to form the position of the solar cells in an irregular shape. This is shown in Fig.

In addition, as described above, since the optical fiber cable is formed of a group of optical fibers inserted therein, in order to solve the problem of heat concentration in the solar cell, the sunlight condensed from one Fresnel lens The optical fiber cable may be appropriately branched so as to be received by a plurality of solar cells.

Also, according to the performance of the solar cell receiving sunlight, the optical fiber inside the optical fiber cable can be a multimode optical fiber, a single mode optical fiber, or a mixed structure thereof, and solar light suitable for each solar cell can be input will be.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, You will understand. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive.

110: Fresnel lens
120: rod lens
130, 131, 132, 133, 134, 135, 136:
140: heat sink
150: Fiber optic cable
151, 154, 157: Optical fiber
152, 155, 158:
153, 156, 159:
200, 300: condensing type solar cell module
260: auxiliary heat-

Claims (7)

At least one Fresnel lens for condensing sunlight;
At least one optical fiber cable provided for totally reflecting and condensing the light condensed by the Fresnel lens;
At least one solar cell receiving the light transmitted through the optical fiber cable; And
And a heat sink for dissipating heat of the solar cell. The method according to claim 1,
The optical fiber cable includes:
A core portion through which the condensed light is transmitted by the Fresnel lens; And
And a cladding portion surrounding the core portion,
Wherein the core portion has a diameter of 200 mu m or less and a refractive index difference between the core portion and the cladding portion is 4% or less. 3. The method according to claim 1 or 2,
Wherein the photovoltaic cell is formed to have a size equal to or smaller than a cross sectional area of the optical fiber cable and electrically connected to each other. The method of claim 3,
Wherein the light-condensing solar cell module further comprises an auxiliary heat-dissipating unit connected to the heat sink. 5. The method of claim 4,
Wherein the arrangement of the Fresnel lens and the arrangement of the solar cell are arranged at predetermined predetermined positions, respectively. 6. The method of claim 5,
Wherein the solar cell is a compound solar cell using a III-V compound semiconductor. The method of claim 3,
Wherein the optical fiber cable is any one of a set of multimode optical fibers, a set of single mode optical fibers, and a set of optical fibers formed by mixing the multimode optical fiber and the single mode optical fiber.

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