Solar cell module inspection device, solar cell module inspection method, and solar cell module manufacturing method

Abstract

To provide a solar cell module inspection device that is able to independently inspect front and rear solar cells of a tandem solar cell module.SOLUTION: A solar cell module inspection device according to one aspect of the present invention includes: an inspection power supply configured to apply an inspection voltage to a perovskite solar cell and a crystalline silicon solar cell, or an inspection light source configured to emit inspection light to a side of the perovskite solar cell of a solar cell module; a first camera configured to photograph the side of the perovskite solar cell of the solar cell module to obtain a first image; a second camera configured to photograph a side of the crystalline silicon solar cell of the solar cell module to obtain a second image; a difference image generation image configured to generate a difference image between the first image and the second image; a first determination unit configured to determine quality of the perovskite solar cell based on the difference image; and a second determination unit configured to determine quality of the crystal silicon solar cell based on the second image.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a solar cell module inspection device, a solar cell module inspection method, and a solar cell module manufacturing method. [Background technology]

[0002] Tandem solar cell modules are known in which two types of solar cells that absorb different wavelengths are arranged in an overlapping manner to improve the photoelectric conversion efficiency of the solar cell module. A typical example is a solar cell module that uses a perovskite solar cell as the solar cell on the front side and a crystalline silicon solar cell as the solar cell on the back side (see, for example, Patent Document 1).

[0003] Since the solar cells on the front and back sides may be damaged during modularization, it is desirable to inspect the quality of the solar cells on the front and back sides after modularization. Known methods for inspecting solar cells include a method that utilizes the phenomenon in which a solar cell emits light when a voltage is applied to the solar cell (EL: electroluminescence), and a method that utilizes the phenomenon in which a solar cell emits light due to recombination of excited photocarriers when light is irradiated onto the solar cell (PL: photoluminescence) (see, for example, Patent Document 2). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2019 / 087918 [Patent Document 2] JP 2015-59781 A Summary of the Invention [Problem to be solved by the invention]

[0005] When performing EL inspection or PL inspection of a tandem solar cell module, the solar cells on the front and back sides emit light simultaneously, so the solar cells on the front and back sides cannot be inspected independently. Therefore, an object of the present invention is to provide a solar cell module inspection device and a solar cell module inspection method that can inspect the solar cells on the front and back sides of a tandem solar cell module independently, and a solar cell module manufacturing method that can guarantee the performance of the solar cells on the front and back sides. [Means for solving the problem]

[0006] A solar cell module inspection device according to one embodiment of the present invention is a solar cell module inspection device for inspecting a solar cell module having perovskite solar cells and crystalline silicon solar cells that are arranged in a stack and each independently output power, and includes an inspection power supply that applies an inspection voltage to the perovskite solar cells and the crystalline silicon solar cells, or an inspection light source that irradiates inspection light to the perovskite solar cell side of the solar cell module, a first camera that photographs the perovskite solar cell side of the solar cell module to obtain a first image, a second camera that photographs the crystalline silicon solar cell side of the solar cell module to obtain a second image, a differential image generation unit that generates a difference image between the first image and the second image, a first judgment unit that judges the pass / fail of the perovskite solar cells based on the difference image, and a second judgment unit that judges the pass / fail of the crystalline silicon solar cells based on the second image. Effect of the Invention

[0007] According to the present invention, it is possible to provide a solar cell module inspection device and a solar cell module inspection method capable of independently inspecting the solar cells on the front and back of a tandem solar cell module, as well as a solar cell module manufacturing method capable of ensuring the performance of the solar cells on the front and back. [Brief description of the drawings]

[0008] [Figure 1] 1 is a schematic diagram showing the configuration of a first embodiment of a solar cell module inspection device according to the present invention. [Diagram 2] 2 is a flowchart showing the procedure of an embodiment of a solar cell module manufacturing method according to the present invention that can be carried out using the solar cell module inspection apparatus of FIG. [Diagram 3] FIG. 4 is a schematic diagram showing the configuration of a second embodiment of a solar cell module inspection device according to the present invention. [Figure 4] 4 is a flowchart showing the procedure of an embodiment of a solar cell module manufacturing method according to the present invention that can be carried out using the solar cell module inspection apparatus of FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings. Fig. 1 is a schematic diagram showing the configuration of a solar cell module inspection device 1 according to a first embodiment of the present invention.

[0010] The solar cell module inspection device 1 inspects a solar cell module 100 having a perovskite solar cell 101 and a crystalline silicon solar cell 102 that are arranged in a stacked manner and output power independently. Specifically, the solar cell module 100 inspected by the solar cell module inspection device 1 may have one or more perovskite solar cells 101, one or more crystalline silicon solar cells 102 arranged on the back side of the perovskite solar cell 101, a surface protection member 103 that covers the front side of the perovskite solar cell 101, a back protection member 104 that covers the back side of the crystalline silicon solar cell 102, and a sealant 105 that fills the space around the perovskite solar cell 101 and the crystalline silicon solar cell 102 between the surface protection member 103 and the back protection member 104. The perovskite solar cell 101 may be a solar cell submodule in which a plurality of subcells having a first transparent electrode layer, a perovskite photoelectric conversion layer, and a second transparent electrode layer are formed on a substrate. The crystalline silicon solar cell 102 may be configured as a solar cell string in which a plurality of solar cells are mechanically and electrically connected by wiring material.

[0011] The solar cell module inspection apparatus 1 comprises an inspection light source 10 that irradiates inspection light onto the side (front side) of the perovskite solar cell 101 of the solar cell module 100, a first camera 20 that photographs the side (front side) of the perovskite solar cell 101 of the solar cell module 100 to obtain a first image, a second camera 30 that photographs the side (back side) of the crystalline silicon solar cell 102 of the solar cell module 100 to obtain a second image, and a control device 40 that controls the inspection light source 10, the first camera 20 and the second camera 30 and determines the quality of the perovskite solar cell 101 and the crystalline silicon solar cell 102.

[0012] The inspection light source 10 irradiates the entire surface of the solar cell module 100 with inspection light that includes a wavelength that is absorbed by the perovskite solar cell 101 to generate photocarriers (electrons and holes) and a wavelength that is transmitted through the perovskite solar cell 101 and absorbed by the crystalline silicon solar cell 102 to generate photocarriers.

[0013] The first camera 20 photographs the solar cell module 100 from the front side according to instructions from the control device 40, and transmits the obtained data of the first image to the control device 40. The first camera 20 photographs an image of light generated by the recombination of photocarriers in the perovskite solar cell 101 and the crystalline silicon solar cell 102, that is, a photoluminescence image. The first image is acquired as data expressing the color of each pixel by a color value consisting of a plurality of values ​​such as RGB, CMYK, HSV, HSL, LAB, etc. The first camera 20 may be, for example, a camera having a two-dimensional imaging element such as a CMOS image sensor. Note that light other than photoluminescence such as the inspection light of the inspection light source 10 is noise that reduces the accuracy of judging the quality of the perovskite solar cell 101. For this reason, it is preferable that the first camera 20 is placed in a position where the inspection light or its reflected light is not incident, or is controlled to perform shooting after the inspection light source 10 is turned off.

[0014] The second camera 30 photographs the solar cell module 100 from the back side in accordance with instructions from the control device 40, and transmits the obtained second image data to the control device 40. The second camera 30 mainly photographs photoluminescence images of the crystalline silicon solar cells 102. As the second camera 30, a camera similar to the first camera 20 may be used. Note that, for the second camera 30, the positional relationship with the inspection light source 10 does not need to be considered because the crystalline silicon solar cells 102 block the inspection light.

[0015] The control device 40 includes an imaging control unit 41 that controls the inspection light source 10, the first camera 20, and the second camera 30, a differential image generating unit 42 that generates a differential image between the first image and the second image, a first judgment unit 43 that judges the quality of the perovskite solar cell 101 based on the differential image, and a second judgment unit 44 that judges the quality of the crystalline silicon solar cell 102 based on the second image. The control device 40 can be realized, for example, by causing one or more computer devices having a processor (CPU), memory, an input / output interface, etc. to execute an appropriate processing program.

[0016] The photography control unit 41 turns on the inspection light source 10 and causes the first camera 20 and the second camera 30 to capture photoluminescence images (first image and second image). The photography control unit 41 may control the inspection light source 10, the first camera 20, and the second camera 30 so that the first image and the second image can be captured in synchronization with a device that transports the solar cell module 100.

[0017] The differential image generating unit 42 generates a differential image by subtracting the value of each element of the color value of the corresponding pixel of the second image acquired from the second camera 30 from the value of each element of the color value of each pixel of the first image acquired from the first camera 20. Since the perovskite solar cell 101 transmits light in a wavelength range generated by the photoluminescence of the crystalline silicon solar cell 102, the first image is an image in which the photoluminescence image of the perovskite solar cell 101 and the photoluminescence image of the crystalline silicon solar cell 102 are superimposed. Therefore, the differential image generating unit 42 generates an image in which the component due to the photoluminescence of the crystalline silicon solar cell 102 is removed from the first image. The differential image generating unit 42 preferably corrects the color value of at least one of the first image and the second image in order to eliminate the influence of the sensitivity difference between the first camera 20 and the second camera 30, the attenuation of light due to the structure of the solar cell module 100, and the like.

[0018] The first determination unit 43 determines the presence or absence of defects in the perovskite solar cell 101 based on the difference image generated by the difference image generation unit 42. When making a determination based on the difference image, the first determination unit 43 preferably performs a masking process to exclude the outer region of the perovskite solar cell 101 and the region where the metal electrode or the like is arranged from the determination target. The determination of the presence or absence of defects can be performed by a well-known image processing technique. The first determination unit 43 may be configured to determine a pixel region having a small color value in the difference image as a defective region. The first determination unit 43 may also be configured to store a difference image generated by acquiring a first image and a second image of a solar cell module 100 without defects in advance as a reference image, and to determine a pixel region having a large difference in color value between the difference image generated from the first image and the second image of the solar cell module 100 to be inspected and the reference image as a defective region. In order to suppress erroneous determination due to noise, the first determination unit 43 may determine a defective region when not only the color value of each pixel but also the number of pixels with a small color value, the density, etc. are equal to or greater than a reference value. In addition, the solar cell modules 100 may be classified into three or more quality grades depending on the degree of defects, such as the deviation of color values, the difference value, the number of nonstandard pixels, and the density.

[0019] The second judgment unit 44 judges the presence or absence of defects in the crystalline silicon solar cell 102 based on the second image acquired from the second camera 30 by the same method as the first judgment unit 43 judges the presence or absence of defects in the perovskite solar cell 101. The crystalline silicon solar cell 102 does not transmit light in a wavelength range generated by the photoluminescence of the perovskite solar cell 101, and the amount of light generated by the photoluminescence of the perovskite solar cell 101 and incident on the crystalline silicon solar cell 102 is sufficiently small compared to the amount of inspection light transmitted through the perovskite solar cell 101 and incident on the crystalline silicon solar cell 102, so the second image can be considered to be an image of photoluminescence by the inspection light of the crystalline silicon solar cell 102. In addition, in order to eliminate the influence of differences in the light emission state of the perovskite solar cell 101, the second judgment unit 44 preferably performs a masking process to exclude from the judgment target at least pixels in the non-existence area of ​​the crystalline silicon solar cell 102 from the second image.

[0020] Fig. 2 is a flow chart showing the steps of a solar cell module manufacturing method capable of manufacturing the solar cell module 100. The solar cell module manufacturing method of Fig. 2 can be carried out using a solar cell module inspection apparatus 1. The solar cell module manufacturing method of Fig. 2 is one embodiment of the solar cell module manufacturing method according to the present invention.

[0021] The solar cell module manufacturing method of this embodiment includes a perovskite solar cell forming step (step S01), a crystalline silicon solar cell forming step (step S02), a solar cell module forming step (step S03), an inspection light irradiation step (step S04), a photographing step (step S05), a difference image generating step (step S06), a perovskite solar cell determining step (step S07), a crystalline silicon solar cell determining step (step S08), and a sorting step (step S09). Steps S04 to S08 are a procedure of one embodiment of the solar cell module inspection method according to the present invention.

[0022] In the perovskite solar cell formation step of step S01, a perovskite solar cell 101 is formed. The perovskite solar cell 101 can be formed by a known method.

[0023] In the crystalline silicon solar cell formation step of step S02, a crystalline silicon solar cell 102 is formed. A well-known method can be used as a method for forming the crystalline silicon solar cell 102. The order of this crystalline silicon solar cell formation step and the perovskite solar cell formation step is not limited to the order described above, and they may be performed in parallel.

[0024] In step S03, the solar cell module formation process, the perovskite solar cells 101 and the crystalline silicon solar cells 102 are sealed between the front surface protective member 103 and the back surface protective member 104 by a sealing material 105 to obtain the solar cell module 100. The sealing of the perovskite solar cells 101 and the crystalline silicon solar cells 102 can be performed by a well-known method such as vacuum heat pressing.

[0025] In the inspection light irradiation step of step S04, the inspection light source 10 irradiates the solar cell module 100 with inspection light from the perovskite solar cell 101 side.

[0026] In the photographing process of step S05, the first camera 20 photographs the perovskite solar cell 101 side of the solar cell module 100 to obtain a first image, and the second camera 30 photographs the crystalline silicon solar cell 102 side of the solar cell module 100 to obtain a second image. To ensure that the light emission states of the perovskite solar cell 101 and the crystalline silicon solar cell 102 are the same, it is preferable that the first image and the second image are photographed simultaneously.

[0027] In the difference image generating step S06, a difference image between the first image and the second image is generated. Specifically, as described above, the color value obtained by subtracting the color value of the second image from the color value of the first image for each pixel is set as the color value of the difference image. In addition, the data of at least one of the first image and the second image may be corrected to match the luminance of the second image to the noise level of the first image.

[0028] In the perovskite solar cell determination step of step S07, the first determination unit 43 determines whether the perovskite solar cell 101 is good or bad based on the difference image.

[0029] In the crystalline silicon solar cell determination step of step S08, the second determination unit 44 determines the quality of the crystalline silicon solar cell 102 based on the second image. The order of this crystalline silicon solar cell determination step, the differential image generation step, and the perovskite solar cell determination step is not limited to the order described.

[0030] In the sorting process of step S09, the solar cell modules 100 are sorted (physically separated) according to the level of defects based on the judgment results of the perovskite solar cell judgment process and the crystalline silicon solar cell judgment process. As a simple example, in the sorting process, it is possible to keep only non-defective products with defects below a certain standard and reject defective products with defects exceeding a certain standard.

[0031] In the solar cell module inspection device 1 and the solar cell module inspection device and solar cell module manufacturing method that can be implemented using the solar cell module inspection device 1 described above, a difference image between the first image and the second image, that is, a photoluminescence image of only the perovskite solar cell 101 obtained by removing the light component emitted by the crystalline silicon solar cell 102 from the first image, is generated. This makes it possible to independently inspect the perovskite solar cell 101 and the crystalline silicon solar cell 102, that is, to judge whether they are good or bad individually. This ensures the accuracy of the judgment, so that only defect-free solar cell modules can be made into the final product.

[0032] Fig. 3 is a schematic diagram showing the configuration of a solar cell module inspection apparatus 1A according to a second embodiment of the present invention. The solar cell module inspection apparatus 1A inspects a solar cell module 100 in the same manner as the solar cell module inspection apparatus 1 in Fig. 1. In the solar cell module inspection apparatus 1A in Fig. 3, components similar to those in the solar cell module inspection apparatus 1 in Fig. 1 are given the same reference numerals, and duplicated explanations may be omitted.

[0033] The solar cell module inspection apparatus 1A comprises an inspection power supply 10A that applies an inspection voltage to each of the perovskite solar cells 101 and the crystalline silicon solar cells 102, a first camera 20 that photographs the perovskite solar cell 101 side of the solar cell module 100, a second camera 30 that photographs the crystalline silicon solar cell 102 side of the solar cell module 100, and a control device 40A that controls the inspection power supply 10A, the first camera 20 and the second camera 30, and determines the quality of the perovskite solar cells 101 and the crystalline silicon solar cells 102.

[0034] Inspection power supply 10A applies a predetermined inspection voltage to each of perovskite solar cell 101 and crystalline silicon solar cell 102, causing them to emit light by electroluminescence. Therefore, in solar cell module inspection apparatus 1A, the first image and the second image captured by first camera 20 and second camera 30 are electroluminescence images.

[0035] The control device 40A includes an imaging control unit 41A that controls the inspection power supply 10A, the first camera 20 and the second camera 30, a differential image generation unit 42 that generates a differential image between the first image and the second image, a first judgment unit 43 that judges the pass / fail of the perovskite solar cell 101 based on the differential image, and a second judgment unit 44 that judges the pass / fail of the crystalline silicon solar cell 102 based on the second image.

[0036] The inspection power supply 10A applies an inspection voltage to the perovskite solar cell 101 and the crystalline silicon solar cell 102, and the first camera 20 and the second camera 30 capture electroluminescence images (first image and second image).

[0037] The solar cell module inspection apparatus 1A in Figure 3 differs from the solar cell module inspection apparatus 1 in Figure 1 only in the method of causing the perovskite solar cells 101 and the crystalline silicon solar cells 102 to emit light, and like the solar cell module inspection apparatus 1 in Figure 1, it can inspect the perovskite solar cells 101 and the crystalline silicon solar cells 102 independently.

[0038] Fig. 4 is a flow chart showing the steps of a solar cell module manufacturing method that can be carried out using the solar cell module inspection apparatus 1 A. The solar cell module manufacturing method of Fig. 4 is one embodiment of the solar cell module manufacturing method according to the present invention.

[0039] The solar cell module manufacturing method of this embodiment includes a perovskite solar cell forming step (step S01), a crystalline silicon solar cell forming step (step S02), a solar cell module forming step (step S03), an inspection voltage application step (step S14), an imaging step (step S05), a difference image generating step (step S06), a perovskite solar cell determining step (step S07), a crystalline silicon solar cell determining step (step S08), and a sorting step (step S09). Steps S14 to S08 are a procedure of one embodiment of the solar cell module inspection method according to the present invention.

[0040] As is clear from the explanation of the solar cell module inspection apparatus 1A, the solar cell module manufacturing method of Fig. 4 differs from the solar cell module manufacturing method of Fig. 1 only in that, instead of the inspection light irradiation step (step S04), it includes an inspection voltage application step (step S14) of applying an inspection voltage to the perovskite solar cell 101 and the crystalline silicon solar cell 102 to cause the perovskite solar cell 101 and the crystalline silicon solar cell 102 to emit electroluminescence. Therefore, the solar cell module manufacturing method of Fig. 4 can individually determine the quality of the perovskite solar cell 101 and the crystalline silicon solar cell 102, similar to the solar cell module manufacturing method of Fig. 1.

[0041] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-mentioned embodiments, and various modifications and variations are possible. For example, the solar cell module inspection device according to the present invention may be configured to manually perform irradiation of inspection light or application of inspection voltage and capture of the first and second images. In addition, in the solar cell module inspection method according to the present invention, the differential image generating step, the perovskite solar cell determining step, and the crystalline silicon solar cell determining step may be performed according to a user's operation using general-purpose image processing software or the like. [Explanation of symbols]

[0042] 1,1A Solar cell module inspection equipment 10 Inspection light source 10A Test Power Supply 20 Camera No. 1 30 Second Camera 40,40A Control Device 41, 41A Imaging control unit 42 Differential image generation unit 43 1st Judgment Section 44 Second Judgment Section 100 Solar Modules 101 Perovskite solar cells 102 Crystalline silicon solar cells 103 Surface protection materials 104 Back surface protection material 105 Encapsulating material

Claims

1. A solar cell module inspection device for inspecting a solar cell module having perovskite solar cells and crystalline silicon solar cells arranged in a stack and each independently outputting electric power, comprising: an inspection power supply that applies an inspection voltage to the perovskite solar cell and the crystalline silicon solar cell, or an inspection light source that irradiates an inspection light onto the perovskite solar cell side of the solar cell module; A first camera that captures a first image of the perovskite solar cell side of the solar cell module; a second camera that captures a second image of the crystalline silicon solar cell side of the solar cell module; a difference image generating unit that generates a difference image between the first image and the second image; A first determination unit that determines whether the perovskite solar cell is good or bad based on the difference image; a second determination unit that determines whether the crystalline silicon solar cell is good or bad based on the second image; A solar cell module inspection device comprising:

2. The solar cell module inspection device according to claim 1 , wherein the differential image generating section corrects a color value of at least one of the first image and the second image.

3. The solar cell module inspection device according to claim 1 , wherein the second determination unit excludes an image of an area where no crystalline silicon solar cell is present from the second image.

4. A solar cell module inspection method for inspecting a solar cell module having perovskite solar cells and crystalline silicon solar cells arranged in a stack and each independently outputting power, comprising: applying an inspection voltage to the perovskite solar cell and the crystalline silicon solar cell, or irradiating an inspection light onto the perovskite solar cell side of the solar cell module; photographing a side of the solar cell module containing the perovskite solar cells to obtain a first image, and photographing a side of the solar cell module containing the crystalline silicon solar cells to obtain a second image; generating a difference image between the first image and the second image; determining whether the perovskite solar cell is good or bad based on the difference image; determining whether the crystalline silicon solar cell is good or bad based on the second image; A solar cell module inspection method comprising:

5. obtaining a solar cell module by stacking and sealing perovskite solar cells and crystalline silicon solar cells, each of which independently outputs power; A step of inspecting the solar cell module by the solar cell module inspection method according to claim 4; A solar cell module manufacturing method comprising:

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