UV attenuation algorithm based on solar cells

Abstract

The invention discloses a UV attenuation algorithm based on a solar cell, which belongs to the technical field of solar cell testing, and comprises the following steps: S1, confirming the maximum value λ of the test wavelength range max and the minimum value λ min ; S2, divide the test wavelength range into n parts evenly, and then take the test band λ in each part i ; S3, test the test band λ selected in S2 i The corresponding reflectivity r (λ i ), through the reflectivity r (λ i ) Calculate the UV reflectivity Ruv of the solar cell, S4, use the obtained Ruv to calculate the UV attenuation Suv of the solar cell = A*Ruv + B. Compared with the prior art, the UV attenuation algorithm based on solar cells of the present invention has the following advantages: 1) It can greatly reduce the UV attenuation test time and is convenient for large-scale testing; 2) It is conducive to increasing UV reflectivity monitoring during process adjustments and new material introduction in subsequent texturing and positive film processes to ensure that the UV attenuation is qualified.

Description

Technical Field

[0001] The invention belongs to the technical field of solar cell testing, and in particular relates to a UV attenuation algorithm based on solar cells. Background Art

[0002] In the field of solar cell technology, with the widespread application of solar cells, the stability of their performance and service life have become important research directions. Solar cells are affected by environmental factors, especially long-term exposure to ultraviolet (UV), which will cause their performance to gradually decline. This phenomenon is called UV attenuation. UV attenuation is one of the key factors affecting the working efficiency of solar cells.

[0003] However, there are certain research and testing challenges for the life attenuation characteristics of solar cells under ultraviolet radiation. Specifically, the ultraviolet attenuation test of photovoltaic modules has a special detection process and a long time period. From collecting samples to making modules, to sending them for testing, and finally getting the data, the entire process is basically measured in months. Although this long-term test can more accurately reflect the long-term performance of the module in the actual use environment, its complexity and periodicity also make this method have great limitations in practical applications.

[0004] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention and should not be regarded as an acknowledgment or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art. Summary of the invention

[0005] The purpose of the present invention is to provide a UV attenuation algorithm based on solar cells, which can solve the technical problems raised in the above background technology.

[0006] In order to achieve the above object, a technical solution provided by a specific embodiment of the present invention is as follows:

[0007] The UV attenuation algorithm based on solar cells includes the following steps:

[0008] S1. Confirm the maximum value λ of the test wavelength range max and the minimum value λ min ;

[0009] S2. Divide the test wavelength range into n parts evenly, and then take the test band λ in each part i ;

[0010] S3, test the test band λ selected in S2 i The corresponding reflectivity r (λ i ), and then substitute it into formula 1 to calculate the UV reflectivity Ruv of the solar cell

[0011] "Formula One"

[0012] Wherein, Ruv is the final calculated value of ultraviolet reflectivity, k is any positive real number, n is a non-zero natural number, S(λ i ) is the wavelength λ i irradiance;

[0013] S4, using the obtained Ruv, calculate the UV attenuation of the solar cell Suv = A*Ruv + B;

[0014] Among them, A=-0.01~0, B=0.005~0.03.

[0015] In one or more embodiments of the present invention, in S2, the calculation formula of λi is:

[0016] "Formula 2"

[0017] In one or more embodiments of the present invention, in S2, the calculation formula of λi is:

[0018] "Formula Three"

[0019] In one or more embodiments of the present invention, the min ≥280nm, the λ min <λ max ≤400nm.

[0020] In one or more embodiments of the present invention, the i ≥280, and the λ i <300, the S(λ i )=0.1~1.2.

[0021] In one or more embodiments of the present invention, the i ≥300, and the λ i <310, the S(λ i )=4.5~6.

[0022] In one or more embodiments of the present invention, the i ≥310, and the λ i <315, the S(λ i )=3~4.5.

[0023] In one or more embodiments of the present invention, the i ≥315, and the λ i ≤350, the S(λ i )=0.5~4.

[0024] In one or more embodiments of the present invention, the i >350, and the λ i ≤390, the S(λ i )=8~30.

[0025] In one or more embodiments of the present invention, the i >390, and the λ i ≤400, the S(λ i )=4.5~6.

[0026] Compared with the prior art, the UV attenuation algorithm based on solar cells of the present invention has the following advantages:

[0027] 1) It can greatly reduce the UV attenuation test time and facilitate large-scale testing;

[0028] 2) It is beneficial to increase UV reflectivity monitoring during the subsequent texturing process and positive film process adjustment and the introduction of new materials to ensure that the UV attenuation is qualified;

[0029] 3) It is helpful to pre-judge the effectiveness of new UV improvement solutions for anti-UV attenuation, thereby speeding up experimental verification efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0031] Figure 1 Schematic diagram of the relationship between wavelength and reflectivity of 15 test sheets in one embodiment of the present invention;

[0032] Figure 2 The reflectivity test data and UV reflectivity calculation value data of some test pieces in one embodiment of the present invention are shown in FIG. Figure 1 ;

[0033] Figure 3 The reflectivity test data and UV reflectivity calculation value data of some test pieces in one embodiment of the present invention are shown in FIG. Figure 2 ;

[0034] Figure 4 The reflectivity test data and UV reflectivity calculation value data of some test pieces in one embodiment of the present invention are shown in FIG. Figure 3 ;

[0035] Figure 5 A data graph showing the calculated values ​​of UV attenuation and UV reflectivity of 15 test sheets in one embodiment of the present invention;

[0036] Figure 6 It is a linear fitting diagram of UV attenuation data and UV reflectivity calculation values ​​of 15 test sheets in one embodiment of the present invention. DETAILED DESCRIPTION

[0037] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0038] During the research, the actual tested wavelength range is 280nm to 400nm. After a specific and abstract analysis of the data, it was decided to discard the wavelength images from 280nm to 300nm. The reflectivity corresponding to the wavelength from 300nm to 400nm is as follows: Figure 1 As shown, at the same time, because when the wavelength is in the range of 300nm to 400nm, a vertex appears, and a quasi-quadratic function must be used to represent the change of related data, there is a large uncertainty, including but not limited to the same reflectivity corresponding to two different wavelengths, which does not meet the purpose of this study. When the wavelength is between 300nm and 350nm, its data image is a linear function with strong certainty. Therefore, in this embodiment, the focus is on the relevant data when the wavelength is between 300nm and 350nm.

[0039] Embodiment 1:

[0040] The UV attenuation algorithm based on solar cells in one embodiment of the present invention comprises the following steps:

[0041] S1. Confirm the maximum value λ of the test wavelength range max and the minimum value λ min , where λ min ≥280nm,λ max >λ min ≤400nm.

[0042] S2. Divide the test wavelength range into n parts evenly, and then take the test band λ in each part i ;

[0043] Among them, λ i The calculation formula of can be obtained from Formula 2 or Formula 3, that is,

[0044] "Formula 2" or

[0045] "Formula Three"

[0046] S3, test the test band λ selected in S2 i The corresponding reflectivity r (λ i ), and then substitute it into formula 1 to calculate the UV reflectivity Ruv of the solar cell

[0047] "Formula One"

[0048] Where Ruv is the final calculated value of UV reflectivity, k is any positive real number, n is a non-zero natural number, S(λ i ) is the wavelength λ i Irradiance, when 280≤λ i When <300, S(λ i ) is 0.1~1.2. When 300≤λ i <310, S(λ i ) is 4.5~6, when 310≤λ i <315, S(λ i ) is 3~4.5, when 315≤λ i ≤350, S (λ i ) is 0.5~4, when 350<λ i ≤390, S (λ i ) is 8~30, when 390<λ i ≤400, S (λ i ) is 4.5~6.

[0049] S4. Use the obtained Ruv to calculate the UV attenuation of the solar cell Suv=A*Ruv+B, where A=-0.01~0, B=0.005~0.03.

[0050] Embodiment 2:

[0051] Theoretically, it can be determined that only ultraviolet light with a wavelength of 300-350nm will cause ultraviolet attenuation, so the subsequent monitoring only needs to focus on the reflectivity of ultraviolet light in this band. In order to verify the correlation between UV reflectivity and UV attenuation in the present invention, 15 batteries with different reflectivity were extracted and numbered. After testing the UV reflectivity data of these 15 batteries, they were sent to the ultraviolet attenuation test. In order to facilitate data analysis, Figure 2~Figure 4As shown, the reflectivity curves of the wavelength bands of 300nm, 305nm, 310nm, 315nm, 320nm, 325nm, 330nm, 335nm, 340nm, 345nm, and 350nm are converted into a specific number.

[0052] In order to further verify the algorithm, the maximum value of the test wavelength interval λ is determined in the 15 cells with different reflectivity. max 350, minimum value λ min 300, and divide the test wavelength range evenly into multiple parts, and take the test band λ in each part i In this embodiment, λ i They are 300, 305, 310, 315, 320, 325, 330, 335, 340, 345, and 350 respectively. And according to λ i Test the corresponding reflectivity r(λ i ), the reflectivity r(λ i ) into formula 1:

[0053] "Formula One"

[0054] Calculation is performed in .

[0055] According to formula 1, the calculated value of Ruv is obtained. The result is as follows Figure 2~Figure 4 As shown, the Ruv of each test piece is obtained, and then the UV attenuation of each test piece is tested by the test equipment. The UV attenuation test results are as follows Figure 5 As shown, the Ruv of each test piece and the UV attenuation of each test piece are compared as follows Figure 6 The linear fitting shown in the figure obtains A and B. Finally, using the A and B obtained by the linear fitting, and substituting A and B into Suv=A*Ruv+B, the UV attenuation of the solar cell is calculated.

[0056] like Figure 6 As shown in the figure, the linear fit shows an obvious negative correlation, which indicates that the higher the UV reflectivity, the lower the UV attenuation, as expected in theory.

[0057] The UV attenuation algorithm based on solar cells of the present invention can greatly reduce the UV attenuation test time and facilitate mass testing. It is beneficial to increase UV reflectivity monitoring during process adjustments and new material introduction in subsequent texturing and positive film processes to ensure that UV attenuation is qualified. It is beneficial to pre-judge the effectiveness of new UV improvement solutions for anti-UV attenuation, thereby accelerating experimental verification efficiency.

[0058] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0059] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. The UV attenuation algorithm based on solar cells is characterized by: The following steps are involved: S1. Confirm the maximum value λ of the test wavelength range max and the minimum value λ min ; S2. Divide the test wavelength range into n parts evenly, and then take the test band λ in each part i ; S3, test the test band λ selected in S2 i The corresponding reflectivity r (λ i ), and then substitute it into formula 1 to calculate the UV reflectivity Ruv of the solar cell; "Formula One" Wherein, Ruv is the final calculated value of ultraviolet reflectivity, k is any positive real number, n is a non-zero natural number, S(λ i ) is the wavelength λ i irradiance; S4. Use the obtained Ruv to test the UV attenuation of each test piece through the test equipment, perform linear fitting between the Ruv of each test piece and the UV attenuation of each test piece to obtain A and B, and calculate the UV attenuation of the solar cell, Suv=A*Ruv+B; Among them, A=-0.01~0, B=0.005~0.03, λ i =300~350nm.

2. The UV attenuation algorithm based on solar cells according to claim 1, characterized in that: In S2, the calculation formula of λi is: "Formula 2" .

3. The UV attenuation algorithm based on solar cells according to claim 1, characterized in that: In S2, the calculation formula of λi is: "Formula Three" .

4. The UV attenuation algorithm based on solar cells according to claim 1, characterized in that: The lambda i ≥300, and the λ i <310, the S(λ i )=4.5~6.

5. The UV attenuation algorithm based on solar cells according to claim 1, characterized in that: The lambda i ≥310, and the λ i <315, the S(λ i )=3~4.

5.

6. The UV attenuation algorithm based on solar cells according to claim 1, characterized in that: The lambda i ≥315, and the λ i ≤350, the S(λ i )=0.5~4.

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