Method for determining damage threshold of solar cell irradiated by external heat flux based on cell mapping

Abstract

This invention discloses a method for determining the damage threshold of solar cells irradiated by external heat flow based on unit mapping. The main steps are: measuring and calculating the maximum output power reduction η of the cell unit of an M-series N-parallel solar cell array in a single experiment. i,1 (i = 1, 2, 3...M×N), the actual external heat flow intensity distribution on the cell surface is determined based on the damage morphology of the solar cell target and external heat flow measurement data. The average external heat flow intensity I on the surface of each cell is calculated based on the regional coordinates of the cell. i,1 (i = 1, 2, 3...M×N), statistically analyze the datasets (η) of K experiments under the same irradiation time but different external heat flux intensities. i I i (i = 1, 2, 3...M×N×K), plot the η~I relationship curve, specify the threshold value for the maximum output power reduction of the solar cell, and use the η~I relationship curve to give the corresponding external heat flux intensity threshold. This invention can provide accurate damage criteria for assessing the external heat flux irradiation effect.

Description

Technical Field

[0001] This invention relates to the field of irradiation effect technology, and in particular to a method for determining the damage threshold of solar cells irradiated by external heat flow based on cell mapping. Background Technology

[0002] Spacecraft primarily rely on energy systems to meet the energy needs of their platforms and payloads. Solar cells are a crucial component in these systems, converting solar energy into electricity. Currently, most solar cells used in orbiting spacecraft consist of semiconductor cells and carbon fiber substrates, making them a key component for energy acquisition. However, as exposed components of spacecraft, solar cells have a large surface area and are susceptible to external heat flux and other factors. Severe exposure can damage or even destroy the solar cells, significantly impacting their energy conversion capabilities, leading to insufficient power supply from the energy system and ultimately, the loss of spacecraft functionality.

[0003] To improve the survivability of solar cells in spacecraft, a primary issue is analyzing and obtaining the damage threshold of solar cells under external heat flow irradiation. In the spacecraft field, the damage threshold of a solar cell is defined as the average intensity of the external heat flow that causes the maximum output power of the solar cell to drop to a certain threshold under a given irradiation time. This threshold for the maximum output power drop is closely related to the design of the energy system. Determining the solar cell damage threshold requires extensive equivalent experiments on the ground; however, practical problems such as uneven distribution of external heat flow, high experimental costs, and small data sample sizes make it difficult to accurately determine the damage threshold. Summary of the Invention

[0004] The purpose of this invention is to provide a method for determining the damage threshold of solar cells irradiated by external heat flow based on cell mapping, thereby solving the problem that the damage threshold is difficult to evaluate due to the uneven distribution of external heat flow.

[0005] A method for determining the damage threshold of solar cells irradiated by external heat flux based on cell mapping, the method comprising:

[0006] Measure and calculate the maximum output power drop η of the M-series N-parallel solar cell array unit in a single experiment. i,1 (i = 1, 2, 3...M×N);

[0007] The actual distribution of external heat flux intensity on the cell surface is determined based on the damage morphology of the solar cell target and external heat flux measurement data;

[0008] The external heat flux intensity I on the surface of each cell is calculated based on the regional coordinates of the cell and the actual external heat flux intensity distribution. i,1 (i = 1, 2, 3...M×N);

[0009] Based on the maximum output power drop value η i,1 The external heat flux intensity I on the surface of each cell i,1 Data sets (η) of K experiments under the same irradiation time but different external heat flow intensities. i I i )(i=1, 2, 3...M×N×K);

[0010] Based on the dataset from K experiments, the corresponding external heat flow intensity threshold is obtained.

[0011] In one embodiment, the measurement and calculation of the maximum output power drop η of the M-string N-parallel solar cell array unit cells in a single experiment i,1 include:

[0012] The same measuring equipment was used for measurements before and after the experiment, and the measurement of each cell in the solar array unit cell included measuring each cell individually.

[0013] In one embodiment, the damaged morphology of the solar cell target is an image with no rotation, trapezoidal deformation, and an aspect ratio consistent with the actual target.

[0014] In one embodiment, the damaged morphology of the solar cell target is a frontal image with no rotation, trapezoidal deformation, and an aspect ratio consistent with the actual target.

[0015] In one embodiment, the damage morphology of the solar cell target is represented by a frontal image, in one of the following image formats: g format, jpeg format, bmp format, or png format.

[0016] In one embodiment, the external heat flow intensity I on the surface of each cell is calculated based on the regional coordinates of the cell and the actual external heat flow intensity distribution. i,1 include:

[0017] The average intensity of external heat flow on the surface of each cell is calculated based on the coordinates of the individual cell within the entire solar cell.

[0018] In one embodiment, the maximum output power drop value η i and the average intensity of external heat flow I i Maintain a one-to-one correspondence.

[0019] In one embodiment, obtaining the corresponding external heat flux intensity threshold based on the dataset of K experiments includes:

[0020] Plot the η-I relationship curve based on the dataset from K experiments;

[0021] Set a threshold for the maximum output power reduction of the solar cell;

[0022] Based on the maximum output power reduction threshold of the solar cell, the corresponding external heat flux intensity threshold is obtained using the η-I relationship curve.

[0023] In one embodiment, the actual external heat flux intensity distribution on the battery surface is a part of the overall external heat flux distribution.

[0024] In one embodiment, the contour lines of the external heat flux intensity and the boundaries of the damage morphology remain matched.

[0025] This invention solves the problem of difficulty in evaluating the damage threshold due to uneven distribution of external heat flux caused by irradiation, and maximizes the utilization of a small amount of experimental data to evaluate the damage threshold of solar cells, laying the foundation for the protection research of solar cells in spacecraft. Attached Figure Description

[0026] To more clearly illustrate the technical solutions of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some examples of this application. For those skilled in the art, other drawings can be obtained based on these drawings without exceeding the scope of protection claimed by this application.

[0027] Figure 1 Flowchart of the method for determining the damage threshold of solar cells provided in this embodiment of the invention;

[0028] Figure 2 The solar cell damage morphology diagram provided in the embodiments of the present invention;

[0029] Figure 3 The measurement results of the maximum output power reduction of the unit cell provided in the embodiment of the present invention are shown in the figure.

[0030] Figure 4 The diagram illustrating the calculation process of the actual external heat flux intensity distribution on the surface of a solar cell provided in this embodiment of the invention;

[0031] Figure 5 The embodiment of the present invention provides a calculation diagram of the external heat flux intensity distribution on the surface of the cell.

[0032] Figure 6 The η-I curve provided in the embodiments of the present invention. Detailed Implementation

[0033] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. The advantages and features of the present invention will become clearer from the following description and claims.

[0034] While the invention can be extended in many forms of modification and substitution, and the specification also provides some specific embodiments and detailed descriptions, it should be understood that the inventors' intention is not to limit the invention to the specific embodiments described. On the contrary, the inventors' intention is to protect all improvements, equivalent substitutions and modifications made within the spirit or scope defined by this claim.

[0035] A method for determining the damage threshold of solar cells irradiated by external heat flux based on cell mapping, the method comprising:

[0036] Measure and calculate the maximum output power drop ηi,1 (i=1,2,3……M×N) of the M-series N-parallel solar cell array unit in a single experiment;

[0037] The actual distribution of external heat flux intensity on the cell surface is determined based on the damage morphology of the solar cell target and external heat flux measurement data;

[0038] The external heat flow intensity Ii,1 (i=1,2,3……M×N) on the surface of each unit cell is calculated based on the regional coordinates of the unit cell and the actual external heat flow intensity distribution.

[0039] Based on the maximum output power decrease value ηi,1, the external heat flow intensity Ii,1 on the surface of each cell is used to statistically analyze the dataset (ηi, Ii) (i = 1, 2, 3... M × N × K) of K experiments under the same irradiation time but different external heat flow intensities.

[0040] Based on the dataset from K experiments, the corresponding external heat flow intensity threshold is obtained.

[0041] In one embodiment, measuring and calculating the maximum output power drop ηi,1 of a single experimental M-string N-parallel solar cell array unit includes:

[0042] The same measuring equipment was used for measurements before and after the experiment, and the measurement of each cell in the solar array unit cell included measuring each cell individually.

[0043] In one embodiment, the damaged morphology of the solar cell target is an image with no rotation, trapezoidal deformation, and an aspect ratio consistent with the actual target.

[0044] In one embodiment, the damaged morphology of the solar cell target is a frontal image with no rotation, trapezoidal deformation, and an aspect ratio consistent with the actual target.

[0045] In one embodiment, the damage morphology of the solar cell target is represented by a frontal image, in one of the following image formats: g format, jpeg format, bmp format, or png format.

[0046] In one embodiment, calculating the external heat flux intensity Ii,1 on the surface of each cell based on the regional coordinates of the cell and the actual external heat flux intensity distribution includes:

[0047] The average intensity of external heat flow on the surface of each cell is calculated based on the coordinates of the individual cell within the entire solar cell.

[0048] In one embodiment, the maximum output power drop value ηi and the average intensity of external surface heat flux Ii maintain a one-to-one correspondence.

[0049] In one embodiment, obtaining the corresponding external heat flux intensity threshold based on the dataset of K experiments includes:

[0050] Plot the η-I relationship curve based on the dataset from K experiments;

[0051] Set a threshold for the maximum output power reduction of the solar cell;

[0052] Based on the maximum output power reduction threshold of the solar cell, the corresponding external heat flux intensity threshold is obtained using the η-I relationship curve.

[0053] In one embodiment, the actual external heat flux intensity distribution on the battery surface is a part of the overall external heat flux distribution.

[0054] In one embodiment, the contour lines of the external heat flux intensity and the boundaries of the damage morphology remain matched.

[0055] In one embodiment, this application provides a method for determining the damage threshold of a solar cell, comprising the following steps: measuring and calculating the maximum output power reduction value ηi,1 (i = 1, 2, 3... M × N) of a single experimental M-series N-parallel solar cell array unit cells; determining the actual external heat flow intensity distribution on the cell surface based on the damage morphology of the solar cell target and external heat flow measurement data; calculating the average external heat flow intensity Ii,1 (i = 1, 2, 3... M × N) on the surface of each unit cell based on the regional coordinates of the unit cell; statistically analyzing the dataset (ηi, Ii) (i = 1, 2, 3... M × N × K) of K experiments under different external heat flow intensities for the same irradiation time; plotting the η-I relationship curve; specifying the maximum output power reduction threshold value of the solar cell; and using the η-I relationship curve to give the corresponding external heat flow intensity threshold.

[0056] By adopting the above technical solution, the average intensity of external heat flux on the surface of a single cell is used instead of the average intensity of external heat flux on the entire solar cell surface, thus solving the problem of difficulty in evaluating the damage threshold due to uneven distribution of irradiated external heat flux. Furthermore, the maximum output power reduction value of a single cell is used instead of the maximum output power reduction value of the entire solar cell, and a curve relationship between the maximum output power reduction value of a single cell and the average intensity of external heat flux on the surface of the single cell is established, thereby expanding the data volume by M×N times and solving the problem of small experimental sample size. Therefore, this lays the foundation for research on the protection of solar cells in spacecraft.

[0057] As one possible approach, the measurement of the maximum output power drop of the cell should be performed using the same measuring device before and after the experiment.

[0058] As one possible implementation, the record of the maximum output power drop of the cell should include each cell.

[0059] As one possible implementation, the format of the solar cell target damage image includes any one of the following formats: jpg, jpeg, bmp, or png.

[0060] As one possible implementation, the damaged image of the solar cell target is a frontal image.

[0061] As one possible implementation, the damaged image of the solar cell target should be free from rotation and trapezoidal deformation, and its aspect ratio should be consistent with that of the actual target.

[0062] As one possible approach, the actual distribution of external heat flux intensity on the battery surface can be determined by using images of the damaged morphology and external heat flux measurement data.

[0063] As one possible approach, the average intensity of external heat flux on the surface of each cell is calculated based on the coordinates of the individual cell within the entire solar cell.

[0064] As one possible implementation, the maximum output power reduction η of the single-cell battery i and the average intensity of external heat flow I i A one-to-one correspondence should be maintained.

[0065] As one possible approach, the (η) values ​​under all operating conditions with different external heat flux intensities and the same irradiation time should be statistically analyzed. i I i )data.

[0066] As one possible implementation, based on the statistically obtained (η) i I iThe dataset provides external heat flux thresholds corresponding to different maximum output power decrease values, including:

[0067] Based on the statistical results (η) i I i Plot the η-I relationship curve using the dataset;

[0068] Specify the threshold value for the maximum output power reduction of the solar cell;

[0069] The corresponding external heat flux intensity threshold is given by using the η-I relationship curve.

[0070] In one embodiment, refer to Figure 1 The method for determining the damage threshold of a solar cell provided in this embodiment of the invention includes the following steps:

[0071] S10 measures and calculates the maximum output power drop η of the M-string N-parallel solar array cell unit in one experiment. i,1 (i = 1, 2, 3...M×N);

[0072] Reference Figure 2 A sample of the solar cell after one experiment is provided. In this embodiment, M=4 and N=3. The maximum output power η of each cell is measured using a measuring device. The measurement results in this embodiment are as follows: Figure 3 As shown.

[0073] S11 determines the actual external heat flow intensity distribution on the cell surface based on the damage morphology of the solar cell target and external heat flow measurement data;

[0074] Reference Figure 4 Based on the experimental solar cell damage morphology and external heat flow intensity measurement data provided in the embodiments, the actual external heat flow intensity distribution on the cell surface is calculated and determined. It can be seen that the actual external heat flow intensity distribution on the cell surface is a part of the entire external heat flow distribution. At the same time, the contour lines of the external heat flow intensity should be matched with the damage morphology boundary as much as possible.

[0075] S12 calculates the external heat flux intensity I on the surface of each unit cell based on the regional coordinates of the unit cell. i,1 (i = 1, 2, 3...M×N);

[0076] Reference Figure 5 Based on the actual external heat flux intensity distribution on the battery surface obtained in S11, and considering the regional coordinates of each cell, the external heat flux intensity on the surface of each cell can be calculated separately. Figure 5 Each number in the table represents the average external heat flux intensity of the corresponding cell.

[0077] S13 Statistical analysis of the dataset (η) of K experiments under the same irradiation time but different external heat flow intensities.i I i )(i=1, 2, 3...M×N×K);

[0078] In this embodiment, the number of operating conditions with the same irradiation time but different external heat flow intensities is 2, i.e., K=2. Steps S10 to S12 are repeated, and the datasets (η, I) of the two experiments are summarized. In this embodiment, there are a total of 4×3×2=24 data points.

[0079] S14~S16 plot the η~I relationship curve; specify the threshold value for the maximum output power drop of the solar cell; use the η~I relationship curve to give the corresponding external heat flow intensity threshold.

[0080] Reference Figure 6 Based on the 24 data points obtained from S13, the η-I curve was plotted.

[0081] A threshold value for the maximum output power reduction of the solar cell is specified. In this embodiment, the threshold value for the maximum output power reduction of the solar cell is specified as 55%.

[0082] The corresponding external heat flux intensity threshold is given using the η-I relationship curve. Figure 6 The η-I curve shown uses the x-axis value at the 55% mark on the ordinate, which is 2.55 W / cm². 2 , which is the damage threshold of external heat flow to the solar cell.

[0083] In one embodiment, a computer-readable storage medium is provided having a computer program stored thereon, which, when executed by a processor, implements the steps of the methods described in any of the above embodiments. Those skilled in the art will understand that implementing all or part of the processes in the methods of the above embodiments can be accomplished by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the methods described above.

[0084] A computer device includes a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the steps of the method described in any of the above embodiments. Specifically, the computer device may be a server, and the computer device includes a processor, a memory, a network interface, and a database connected via a system bus.

Claims

1. A method for determining the damage threshold of a solar cell irradiated by external heat flow based on unit mapping, characterized in that, The method includes: Measure and calculate an experiment string and the maximum output power reduction of the solar cell array unit. , ; The actual distribution of external heat flux intensity on the cell surface is determined based on the damage morphology of the solar cell target and external heat flux measurement data; The external heat flux intensity on the surface of each cell was calculated based on the regional coordinates of the cell and the actual distribution of external heat flux intensity. , ; Based on the maximum output power drop value external heat flux intensity on the surface of each cell Statistics on different external heat flux intensities under the same irradiation time The dataset for this experiment ( , ), ; according to The dataset from this experiment yields the corresponding external heat flux intensity threshold.

2. The method according to claim 1, characterized in that, The measurement and calculation of one experiment string and the maximum output power reduction of the solar cell array unit. include: The same measuring equipment was used for measurements before and after the experiment, and the measurement of the solar cell array unit cells included measuring each individual cell.

3. The method according to claim 2, characterized in that, The image shows the damaged morphology of the solar cell target as a non-rotating, trapezoidal deformation image with an aspect ratio consistent with the actual target.

4. The method according to claim 3, characterized in that, The damaged morphology of the solar cell target is a frontal image with no rotation, trapezoidal deformation, and the aspect ratio is consistent with that of the actual target.

5. The method according to claim 4, characterized in that, The damage morphology of the solar cell target is represented by a frontal image, and the image format is one of jpeg, bmp or png.

6. The method according to claim 5, characterized in that, The external heat flow intensity on the surface of each unit cell is calculated based on the regional coordinates of the unit cell and the actual external heat flow intensity distribution. include: The average intensity of external heat flow on the surface of each cell is calculated based on the coordinates of the individual cell within the entire solar cell.

7. The method according to claim 6, characterized in that, The maximum output power drop value and average intensity of external heat flux Maintain a one-to-one correspondence.

8. The method according to claim 7, characterized in that, According to The dataset from this experiment yielded the following corresponding external heat flux intensity thresholds: according to The dataset for this experiment was plotted. Relationship curve; Set a threshold for the maximum output power reduction of the solar cell; Based on the maximum output power reduction threshold of the solar cell, using The corresponding external heat flux intensity threshold is obtained from the relationship curve.

9. The method according to claim 8, characterized in that, The actual external heat flux intensity distribution on the battery surface is a part of the overall external heat flux distribution.

10. The method according to claim 9, characterized in that, The contour lines of the external heat flow intensity and the boundary of the damage morphology are kept consistent.

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