Method for detecting photovoltaic modules

Abstract

The embodiment of the present application relates to the photovoltaic technical field, provide a kind of detection method of photovoltaic module, comprising: the surface of cell piece is laid with solder strip, and solder strip is fixed on cell piece by multiple glue points, multiple cell pieces are connected by solder strip to form cell string;Cell string is detected for first image, to obtain the detection image of each cell piece in cell string;According to detection image, whether each cell piece in cell string meets preset condition is judged, cell string is judged to be sent into next process or repair process;Cell string is detected for second image, to obtain the glue point image of each cell piece in cell string;According to glue point image, the corresponding leakage printing ratio of each cell piece is obtained, according to leakage printing ratio, cell string will be sent into next process, glue supplement process or repair process.The photovoltaic module detection method provided in the embodiment of the present application can at least improve the manufacturing efficiency of photovoltaic module.

Description

TECHNICAL FIELD

[0001] Embodiments of the present application relate to the technical field of photovoltaic technology, and particularly relate to a detection method of a photovoltaic module. BACKGROUND

[0002] A photovoltaic module is a component for generating electricity by using photovoltaic effect, and is usually composed of a cell sheet, a solder strip, a glue film and a cover plate. The cell sheet is an important component of the main module, and the soldering performance of the cell sheet at the module end directly affects the power generation performance and power of the photovoltaic module.

[0003] At present, the main grid technology is a cost reduction technology for removing the main grid and the soldering point on the cell sheet. The main grid-free structure can greatly reduce the silver paste cost of the cell sheet. The existing main grid-free scheme arranges glue points on the main grid-free cell sheet by means of dispensing or printing glue, so as to strengthen the connection between the glue points and the solder strip. After the stringing process, the glue points are completely fixed on the cell sheet, and then the cell sheet is inspected by stringing to check whether there is a defect. When the cell string has problems such as hidden cracks, broken pieces and glue leakage, the operator repairs the cell string. Since the glue points on the cell surface have been cured, the main grid-free cell string can only be repaired by replacing the cell, and cannot replace the solder strip or re-solder as the conventional cell. When the cell has a glue leakage, the operator also repairs it by replacing the cell, which increases the process time and the manufacturing cost of the module.

[0004] Therefore, it is urgent to improve the existing process to improve the manufacturing efficiency of the photovoltaic module. SUMMARY

[0005] Embodiments of the present application provide a detection method of a photovoltaic module, which is at least beneficial to improve the manufacturing efficiency of the photovoltaic module.

[0006] According to some embodiments of the present application, the present application provides a method for detecting a photovoltaic module, comprising: laying a solder strip on a surface of a cell piece, and fixing the solder strip on the cell piece through a plurality of glue points, a plurality of cell pieces are connected through the solder strip to form a cell string; performing first image detection on the cell string to obtain a detection image of each cell piece in the cell string; determining whether each cell piece in the cell string meets a preset condition according to the detection image, if all the cell pieces in the cell string meet the preset condition, the cell string is sent to a next process; if at least one cell piece in the cell string does not meet the preset condition, the cell string is sent to a repair process; performing second image detection on the cell string to obtain a glue point image of each cell piece in the cell string; obtaining a missing printing ratio corresponding to each cell piece according to the glue point image, the missing printing ratio is represented as a ratio of a number of unqualified glue points on each cell piece to a total number of preset glue point positions on the cell piece; if the missing printing ratios of all the cell pieces in the cell string are less than or equal to a first preset value, the cell string is sent to the next process; if the missing printing ratio of at least one cell piece in the cell string is greater than the first preset value, and the missing printing ratios of all the cell pieces in the cell string are less than a second preset value, the cell string is sent to a glue filling process; if the missing printing ratio of at least one cell piece in the cell string is greater than or equal to the second preset value, the cell string is sent to the repair process.

[0007] In some embodiments, if the missing printing ratios of all the cell pieces in the cell string are less than or equal to the first preset value, sending the cell string to the next process comprises: obtaining a glue missing ratio corresponding to each solder strip according to the glue point image, the glue missing ratio is a ratio of a number of unqualified glue points corresponding to each solder strip to a total number of preset glue point positions corresponding to the solder strip; if the glue missing ratio is less than or equal to a third preset value, the cell string is sent to the next process; if the glue missing ratio is greater than the third preset value, the cell string is sent to the glue filling process.

[0008] In some embodiments, the third preset value is 1.5% to 2.5%.

[0009] In some embodiments, if at least one cell piece in the cell string does not meet the preset condition, sending the cell string to the repair process comprises: cutting the cell piece in the cell string that does not meet the preset condition, and connecting the remaining cell pieces in the cell string to form a first recombined cell string; performing second image detection on the first recombined cell string.

[0010] In some embodiments, if the print missing ratio of at least one cell piece in the battery string is greater than or equal to the second preset value, sending the battery string to the repair process includes: cutting the cell piece with the print missing ratio greater than or equal to the second preset value in the battery string, and connecting the remaining cell pieces in the battery string to form a second recombined battery string; if the print missing ratio of all cell pieces in the second recombined battery string is less than or equal to the first preset value, sending the second recombined battery string to the next process; if the print missing ratio of at least one cell piece in the second recombined battery string is greater than the first preset value, and the print missing ratio of all cell pieces in the second recombined battery string is less than the second preset value, sending the second recombined battery string to the glue filling process.

[0011] In some embodiments, after cutting the cell piece with the print missing ratio greater than or equal to the second preset value, the method further includes: connecting the cut cell pieces with the print missing ratio greater than or equal to the second preset value to form a third recombined battery string; and sending the third recombined battery string to the glue filling process.

[0012] In some embodiments, the solder strip is fixed to the cell piece by the plurality of glue points, and the glue points are located on the surface of the solder strip away from the cell piece, or the glue points are located between the solder strip and the cell piece.

[0013] In some embodiments, if the glue points are located on the surface of the solder strip away from the cell piece, the unqualified glue points include the following cases: the surface of the solder strip has no glue points.

[0014] In some embodiments, if the glue points are located between the solder strip and the cell piece, the unqualified glue points include the following cases: the diameter of the glue point is less than the diameter of the solder strip; or the distance between the glue point and the solder strip is greater than 0.

[0015] In some embodiments, the first preset value is 1.5% to 2.5%, and the second preset value is 4% to 6%.

[0016] The technical scheme provided by the embodiments of the present application has at least the following advantages:

[0017] The method for detecting the photovoltaic module provided by the embodiments of the present application connects the cell pieces through the solder strips, and fixes the solder strips on the cell pieces through multiple glue points to form a cell string with no main grid structure. The main grid structure is conducive to reducing the silver paste cost, reducing the light blocking loss, shortening the current transmission path, reducing the series resistance, and improving the power of the photovoltaic module. First, the cell string is subjected to first image detection, and whether each cell piece in the cell string meets the preset requirements is determined according to the result of the first image detection. If at least one cell piece does not meet the preset requirements, the cell string is sent to a repair process; if all the cell pieces meet the preset requirements, the cell string is sent to the next process. The cell piece that does not meet the preset conditions or has defects in the cell string is determined in advance, and the cell string with the cell piece that does not meet the preset conditions is sent to the repair process, so that the problem of time and cost increase caused by the defective cell piece entering the subsequent process and then being repaired can be avoided. Then, the cell string is subjected to second image detection to obtain the glue point image of each cell piece in the cell string, and the corresponding missing printing ratio of each cell piece is obtained according to the glue point image. Based on the missing printing ratio, it is determined in which process the cell string will be sent. For example, if the missing printing ratio of all the cell pieces in the cell string is less than or equal to a first preset value, the cell string is sent to the next process; if the missing printing ratio of at least one cell piece in the cell string is greater than or equal to a second preset value, the cell string is sent to the repair process; if the missing printing ratio of all the cell pieces in the cell string is less than the second preset value, and the missing printing ratio of at least one cell piece is greater than the first preset value, the cell piece is sent to a glue supplementing process. When the missing printing ratio corresponding to the cell piece is greater than the first preset value, it means that the cell piece needs to be supplemented with glue. However, when the missing printing ratio of the cell piece is greater than the second preset value, it means that the cell piece needs to be supplemented with a large amount of glue. Therefore, the glue supplementing time of a single cell piece is relatively long, and if all the cell strings that need to be supplemented with glue are waiting in the glue supplementing process, a large number of cell strings will accumulate in the glue supplementing process, thereby reducing the manufacturing efficiency of the photovoltaic module. Therefore, the cell string corresponding to the cell piece with the missing printing ratio between the first preset value and the second preset value is sent to the glue supplementing process, and the cell string corresponding to the cell piece with the missing printing ratio greater than the second preset value is sent to the repair process, so that different processes can be selected for different cell strings, the problem of a large number of cell strings queuing in the glue supplementing process can be avoided, the production efficiency of the photovoltaic module is improved, and the manufacturing cost is saved. BRIEF DESCRIPTION OF DRAWINGS

[0018] One or more embodiments are illustrated by way of example in the drawings and described herein in connection with the appended drawings, which are not necessarily drawn to scale, unless otherwise specifically indicated. The drawings are included to provide a description of the principles of the application, and not as a limitation of the application. In the drawings, like reference numerals refer to like elements throughout the several views, unless otherwise indicated. Obviously, minor structural details of the drawings are not to be interpreted as limitations of the application.

[0019] Figure 1 A flow chart of a detection method of a photovoltaic module according to an embodiment of the application is provided.

[0020] Figure 2 A structural diagram of a cell string according to an embodiment of the application is provided.

[0021] Figure 3 A structural diagram of another cell string according to an embodiment of the application is provided.

[0022] Figure 4 A flow chart of another detection method of a photovoltaic module according to an embodiment of the application is provided. DETAILED DESCRIPTION

[0023] As known from the background art, the manufacturing efficiency of photovoltaic modules needs to be improved.

[0024] The application provides a detection method of a photovoltaic module, which is at least beneficial to improve the manufacturing efficiency of photovoltaic modules.

[0025] In the description of the embodiments of the application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features.

[0026] In the description of the embodiments of the application, the meaning of "a plurality of" is more than two, unless otherwise explicitly and specifically limited.

[0027] Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are they necessarily mutually exclusive or alternative embodiments. It is explicitly understood that the embodiments described herein are intended to be combined.

[0028] In the description of the embodiments of the present application, the term "and / or" is only used to describe an associated relationship between associated objects, which means that there can be three relationships, for example, A and / or B, which means that there are three cases of A, A and B, and B. In addition, the character " / " in this paper generally represents that the front and rear associated objects are a "or" relationship.

[0029] In the description of the embodiments of the present application, the technical terms such as "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the embodiments of the present application and simplifying the description, and does not indicate or imply that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the embodiments of the present application.

[0030] In the description of the embodiments of the present application, when a certain component "includes" another component, unless otherwise specified, other components are not excluded, and other components can also be further included.

[0031] The terms used in the description of various described embodiments herein are only used to describe specific embodiments, and are not intended to be limiting. As used in the description of various described embodiments and the appended claims, "component" is also intended to include the plural form, unless the context clearly indicates otherwise.

[0032] The embodiments of the present application will be described in detail below with reference to the accompanying drawings. However, those skilled in the art can understand that in the embodiments of the present application, many technical details are proposed in order to make the reader better understand the present application. However, the technical solutions claimed by the present application can be realized even without these technical details and various changes and modifications based on the following embodiments.

[0033] Figure 1 A detection method of a photovoltaic module provided in an embodiment of the present application corresponds to a flowchart.

[0034] Reference Figure 1 The detection method of the photovoltaic module provided in the embodiments of the present application comprises:

[0035] Step S101: Laying a solder strip on the surface of the cell piece, and fixing the solder strip on the cell piece through a plurality of glue points, and connecting a plurality of cell pieces through the solder strip to form a cell string.

[0036] In some embodiments, the battery piece can be any one of a PERC battery (Passivated Emitter and Rear Cell), a PERT battery (Passivated Emitter and Rear Totally-diffused cell), a TOPCon battery (Tunnel Oxide Passivated Contact), a HIT / HJT battery (Heterojunction Technology), or a BC battery (Back Contact).

[0037] In some embodiments, the battery piece can be a single-crystal silicon solar cell, a polycrystalline silicon solar cell, an amorphous silicon solar cell, or a multi-element compound solar cell, which can be a cadmium sulfide solar cell, a gallium arsenide solar cell, a copper indium selenide solar cell, or a perovskite solar cell.

[0038] The battery piece can include a first surface and a second surface arranged opposite to each other. In some embodiments, the first surface of the battery piece has a first grid line, and the second surface of the battery piece has a second grid line, the first grid line and the second grid line having different polarities. In other embodiments, the first grid line and the second grid line can both be located on the first surface of the battery piece.

[0039] Figure 2 A structure diagram of a battery string provided by an embodiment of the present application.

[0040] Reference Figure 2 In some embodiments, the first surface 11 of the battery piece 10 has a first grid line 13, and the second surface 12 of the battery piece 10 has a second grid line (not shown in the figure), the first grid line 13 and the second grid line having different polarities. That is, the grid lines of different polarities on the battery piece 10 are respectively located on the two side surfaces of the battery piece 10.

[0041] Reference Figure 2 When the grid lines of different polarities on the battery piece 10 are respectively located on the two side surfaces of the battery piece 10, in the stringing process, one end of the solder strip 20 is located on the first surface 11 of one battery piece 10 and electrically contacts the first grid line 13 of the battery piece 10, and the other end of the solder strip 20 is located on the second surface 12 of another battery piece 10 and electrically contacts the second grid line of the battery piece 10, thereby forming a battery string structure.

[0042] Figure 3 Another structure diagram of a battery string provided by an embodiment of the present application.

[0043] Reference Figure 3In some other embodiments, the first surface 11 of the battery piece 10 has the first busbar 13 and the second busbar 14, the first busbar 13 has a different polarity from the second busbar 14, and the first busbar 13 and the second busbar 14 are staggered on the first surface 11. That is, the battery piece 10 has busbars of different polarities on the same side surface.

[0044] Reference Figure 3 When the battery piece 10 has busbars of different polarities on the same side surface, in the process of series connection, for the middle battery piece 10, the first busbar 13 on the first surface 11 is connected to the second busbar 14 on the left battery piece 10 through the left solder strip 20, and the second busbar 14 on the first surface 11 is connected to the first busbar 13 on the right battery piece 10 through the right solder strip 20.

[0045] It should be noted that, Figure 2 and Figure 3 The number of battery pieces 10 in the battery string shown in the above embodiments does not constitute a limitation on the battery string, and the number of battery pieces 10 in the battery string can be adjusted according to actual conditions.

[0046] Step S102: performing first image detection on the battery string to obtain a detection image of each battery piece in the battery string; and determining whether each battery piece in the battery string meets a preset condition according to the detection image.

[0047] If all the battery pieces in the battery string meet the preset condition, the battery string is sent to the next process; if at least one battery piece in the battery string does not meet the preset condition, the battery string is sent to the repair process.

[0048] The first image detection method can be photoluminescence (PL) detection or electroluminescence (EL) detection. The PL detection is to evaluate the quality and performance of the photovoltaic component by irradiating the photovoltaic material and measuring its luminescence intensity, which can provide information about the optical properties and defects of the material, and is very helpful for finding defects and damages in the photovoltaic component; the EL detection is to observe the structure and performance inside the solar cell by applying a voltage to the solar cell to make the electrons and holes inside the cell emit light when they recombine, which can directly show potential defects in the solar cell component, such as cracks or fragments, and is of great significance to improve the quality and performance of the photovoltaic component.

[0049] In the process of first image detection, the battery piece that does not meet the preset condition or has defects is determined first, and the battery string with the battery piece that does not meet the preset condition is sent to the repair process, which can avoid the problem of increasing time and cost caused by the defective battery piece entering the subsequent process and then being repaired.

[0050] Step S103: performing second image detection on the battery string to obtain the dot image of each cell in the battery string.

[0051] The second detection image can adopt automated optical inspection (AOI). AOI detection is a device based on optical principle to detect common defects encountered by photovoltaic modules in welding production. The AOI detection principle is to output the reflected light intensity of the detected object in quantitative gray scale value by using camera technology, compare the gray scale value with the standard image, analyze and determine the defects and classify them.

[0052] When the grid lines of two polarities on the cell are located on the two surfaces of the cell respectively, the dot image of the corresponding cell has two groups; when the grid lines of two polarities on the cell are located on the same side surface of the cell, the dot image of the corresponding cell has one group.

[0053] Step S104: obtaining the corresponding missing printing ratio of each cell according to the dot image, the missing printing ratio being represented as the ratio of the number of unqualified dot on each cell to the total number of preset dot positions on the cell.

[0054] If the missing printing ratio of all cells in the battery string is less than or equal to the first preset value (corresponding to condition 1 in the embodiment), the battery string is sent to the next process; if the missing printing ratio of at least one cell in the battery string is greater than the first preset value, and the missing printing ratio of all cells in the battery string is less than the second preset value (corresponding to condition 2 in the embodiment), the battery string is sent to the glue supplementing process; in the same battery string, the number of cells with missing printing ratio greater than the first preset value and less than the second preset value can be multiple, for example, 1, 2, 4 or 6, etc. Figure 1 Figure 1 If the missing printing ratio of at least one cell in the battery string is greater than or equal to the second preset value (corresponding to condition 3 in the embodiment), the battery string is sent to the repair process; in the same battery string, the number of cells with missing printing ratio greater than or equal to the second preset value can be multiple, for example, 1, 2, 4 or 6, etc. Figure 1

[0055] ​​When the grid lines of two polarities are respectively located on two surfaces of the battery piece, the corresponding glue dot images of the battery piece have two groups of corresponding glue dot images. If the bleed-through ratios corresponding to the two groups of glue dot images of the battery piece are both less than or equal to the first preset value, it is judged that the bleed-through ratio of the battery piece is less than or equal to the first preset value; if the bleed-through ratios corresponding to the two groups of glue dot images of the battery piece are both less than the second preset value, and the bleed-through ratio corresponding to at least one group of glue dot images is greater than the first preset value, it is judged that the bleed-through ratio of the battery piece is greater than the first preset value and less than the second preset value; if the bleed-through ratios corresponding to the two groups of glue dot images of the battery piece have at least one group of glue dot images corresponding to a bleed-through ratio greater than or equal to the second preset value, it is judged that the bleed-through ratio of the battery piece is greater than or equal to the second preset value.

[0056] The method for detecting the photovoltaic module provided by the embodiments of the present application connects the cell pieces through the solder strips, and fixes the solder strips on the cell pieces through multiple glue points to form a cell string with no main grid structure. The main grid structure is conducive to reducing the silver paste cost, reducing the light blocking loss, shortening the current transmission path, reducing the series resistance, and improving the power of the photovoltaic module. First, the cell string is subjected to first image detection, and whether each cell piece in the cell string meets the preset requirements is determined according to the result of the first image detection. If at least one cell piece does not meet the preset requirements, the cell string is sent to a repair process. If all the cell pieces meet the preset requirements, the cell string is sent to the next process. The cell piece that does not meet the preset conditions or has defects in the cell string is determined in advance, and the cell string with the cell piece that does not meet the preset conditions is sent to the repair process, so that the problem of time and cost increase caused by the defective cell piece entering the subsequent process and then being repaired can be avoided. Then, the cell string is subjected to second image detection to obtain the glue point image of each cell piece in the cell string, the corresponding missing printing ratio of each cell piece is obtained according to the glue point image, and it is determined based on the missing printing ratio that the cell string will be sent to which process. For example, if the missing printing ratio of all the cell pieces in the cell string is less than or equal to a first preset value, the cell string is sent to the next process. If the missing printing ratio of at least one cell piece in the cell string is greater than or equal to a second preset value, the cell string is sent to the repair process. If the missing printing ratio of all the cell pieces in the cell string is less than the second preset value, and the missing printing ratio of at least one cell piece is greater than the first preset value, the cell piece is sent to a glue supplementing process. When the missing printing ratio corresponding to the cell piece is greater than the first preset value, it means that the cell piece needs to be supplemented with glue. However, when the missing printing ratio of the cell piece is greater than the second preset value, it means that the cell piece needs to be supplemented with a large amount of glue. Therefore, the glue supplementing time of a single cell piece is long, and if all the cell strings that need to be supplemented with glue are waiting in the glue supplementing process, a large number of cell strings will accumulate in the glue supplementing process, thereby reducing the manufacturing efficiency of the photovoltaic module. Therefore, the cell string corresponding to the cell piece with the missing printing ratio between the first preset value and the second preset value is sent to the glue supplementing process, and the cell string corresponding to the cell piece with the missing printing ratio greater than the second preset value is sent to the repair process. Different processes can be selected for different cell strings to avoid the problem of a large number of cell strings queuing in the glue supplementing process, improve the production efficiency of the photovoltaic module, and save the manufacturing cost.

[0057] The preset glue point position on the cell piece refers to the position on the cell piece where the glue point needs to be arranged.

[0058] In some embodiments, the soldering strips are fixed on the battery sheet by the plurality of glue points, which are located on surfaces of the soldering strips away from the battery sheet, and / or which are located between the soldering strips and the battery sheet. The soldering strips are fixed on the battery sheet by the glue points in two ways. In one way, the glue points are first applied on the battery sheet, and then the soldering strips are laid on the battery sheet, and the glue points are cured to fix the soldering strips on the battery sheet, so that the glue points are located between the soldering strips and the battery sheet. In the other way, the soldering strips are first laid on the battery sheet, and then the glue points are applied on the soldering strips, and the glue points are cured to fix the soldering strips on the battery sheet, so that the glue points are located on surfaces of the soldering strips away from the battery sheet.

[0059] If the glue points are located on surfaces of the soldering strips away from the battery sheet, the unqualified glue points include the following cases: the surfaces of the soldering strips are free of the glue points. In the way that the glue points are located on surfaces of the soldering strips away from the battery sheet, the soldering strips are laid first and then the glue points are applied. If the surfaces of the soldering strips are free of the glue points, it can be judged that the glue points are not qualified.

[0060] If the glue points are located between the soldering strips and the battery sheet, the unqualified glue points include the following cases: the diameters of the glue points are smaller than the diameter of the soldering strips, or the distances between the glue points and the soldering strips are greater than 0. In the way that the glue points are located between the soldering strips and the battery sheet, the glue points are applied first and then the soldering strips are laid. The surfaces of the soldering strips are free of the glue points, so it is necessary to judge whether the glue points are unqualified according to the positional relationship between the glue points and the soldering strips. If the diameters of the glue points are smaller than the diameter of the soldering strips, it means that the glue points do not exist or have a small area and cannot fix the soldering strips. If the distances between the glue points and the soldering strips are greater than 0, it means that the glue points are deviated and cannot fix the soldering strips. The above two cases are judged as unqualified glue points.

[0061] In some embodiments, the first preset value can be set to 1.5% to 2.5%, for example, 1.5%, 2%, 2.1%, 2.3%, 2.4%, or 2.5%, etc.

[0062] In some embodiments, the second preset value can be set to 4% to 6%, for example, 4%, 4.4%, 5%, 5.3%, 5.6%, or 6%, etc.

[0063] The first preset value and the second preset value can be adjusted according to the number of soldering strips on the battery sheet and the number of glue points required for a single soldering strip.

[0064] In one specific example, the first preset value is 2.1% and the second preset value is 5%. After the battery string enters the second image detection, each battery piece corresponds to a glue point image. If the print missing ratio of all battery pieces in the battery string is less than or equal to 2.1%, it is determined that the battery string can enter the next process. Since the print missing ratio of all battery pieces is small, the possibility of weld band offset or falling off during the subsequent process is low, which can reduce the possibility of the weld band and the grid line being disconnected after lamination. In order to improve the manufacturing efficiency of the photovoltaic module and save costs, the battery string can be allowed to enter the next process. If the print missing ratio of at least one battery piece in the battery string is greater than or equal to 5%, it indicates that the possibility of weld band offset or falling off during the subsequent process is high, and the battery piece needs to be glued. However, since the print missing ratio of the battery piece is large, the glueing time is long, and after entering the glueing process, the other battery pieces in the battery string need to wait for glueing synchronously, which can easily lead to a decrease in the manufacturing efficiency of the photovoltaic module. Therefore, sending the battery piece to the repair process can reduce the number of battery strings waiting in the glueing process, and improve the manufacturing efficiency of the photovoltaic module. If the print missing ratio of all battery pieces in the battery string is less than 5%, but the print missing ratio of at least one battery piece is greater than 2.1%, it is determined that the battery piece needs to be glued. Since the print missing ratio is small, the glueing time is short, and therefore the waiting time of the single battery string in the glueing process is short. Sending the battery string to the glueing process can make the battery piece with the print missing problem meet the requirements after glueing in a fast way, and thus the battery string can enter the next process quickly.

[0065] In some embodiments, if at least one battery piece in the battery string does not meet the preset condition, the battery string is sent to the repair process, which includes: cutting the battery piece in the battery string that does not meet the preset condition, and connecting the remaining battery pieces in the battery string to form a first recombined battery string; and performing second image detection on the first recombined battery string.

[0066] That is, after cutting the battery piece in the battery string that does not meet the preset condition, the other battery pieces that meet the preset condition are reconnected to form a new first recombined battery string, and then the first recombined battery string is sent to the next process for second image detection. Since the battery pieces in the first recombined battery string all meet the preset condition, the first recombined battery string can be directly sent to the next process for second image detection after recombination, which can improve the repair efficiency of the battery string and save the waiting time of the battery piece that meets the preset condition for the repair of the battery piece in the battery string that does not meet the preset condition.

[0067] It should be noted that the cells in the first recombined cell string can come from different cell strings. Since the cells that do not meet the preset condition are cut out, the number of the remaining cells is less than the total number of cells required in a single cell string. Therefore, the first recombined cell string can be reconnected by the cells that meet the preset condition from multiple cut cell strings.

[0068] In some embodiments, if the shunt ratio of at least one cell in the cell string is greater than the first preset value, and the shunt ratio of all cells in the cell string is less than the second preset value, before the cells are sent to the glue filling process, the method further comprises: obtaining the total number of cells in the cell string whose shunt ratio is greater than the first preset value, if the total number of cells whose shunt ratio is greater than the first preset value is greater than or equal to 1 / 2 of the total number of cells in the cell string, the cell string is sent to the repair process; if the total number of cells whose shunt ratio is greater than the first preset value is less than 1 / 2 of the total number of cells in the cell string, the cell string is sent to the glue filling process. When the number of cells that need to be filled with glue in the cell string is large, a large number of cell strings waiting for glue filling are also likely to accumulate in the glue filling process. Therefore, further judging whether the cell string should enter the glue filling process or the repair process according to the number of cells that need to be filled with glue in the cell string can be beneficial to further improve the manufacturing efficiency of the photovoltaic module.

[0069] In some embodiments, if the shunt ratio of at least one cell in the cell string is greater than or equal to the second preset value, sending the cell string to the repair process comprises: cutting the cells in the cell string whose shunt ratio is greater than or equal to the second preset value, and connecting the remaining cells in the cell string to form a second recombined cell string; if the shunt ratio of all cells in the second recombined cell string is less than or equal to the first preset value, the second recombined cell string is sent to the next process; if the shunt ratio of at least one cell in the second recombined cell string is greater than the first preset value, and the shunt ratio of all cells in the second recombined cell string is less than the second preset value, the second recombined cell string is sent to the glue filling process.

[0070] That is, if the print-through ratio of at least one cell in the cell string is greater than or equal to the second preset value, the cell with the print-through ratio greater than or equal to the second preset value in the cell string is cut, and then the cells with the print-through ratio less than the second preset value in the cell string are reconnected to form a new second reconnected cell string, and then the relationship between the print-through ratio of all cells in the second reconnected cell string and the first preset value is rejudged. Since the cells with the print-through ratio greater than or equal to the second preset value in the cell string have been cut, the print-through ratio of all cells in the second reconnected cell string is less than the second preset value. If the print-through ratio of all cells in the second reconnected cell string is less than the first preset value, it is judged that the second reconnected cell string does not need to be glued and can be allowed to enter the next process. If the print-through ratio of at least one cell in the second reconnected cell string is greater than the first preset value, it is judged that the second reconnected cell string needs to be glued. In this way, after the cells with relatively low print-through ratio are connected to form a second reconnected cell string in the repair process, and then the first preset value is combined to judge whether the second reconnected cell string needs to enter the gluing process or the next process, the repair efficiency of the cell string can be improved, and the cells with relatively low print-through ratio need to wait for the repair time of the cells with relatively high print-through ratio in the cell string.

[0071] It should be noted that the cells in the second reconnected cell string can come from different cell strings. Since the cells with the print-through ratio greater than or equal to the second preset value in the cell string are cut out, the number of remaining cells is less than the total number of cells required in a single cell string, and therefore the second reconnected cell string can be formed by reconnecting the cells with the print-through ratio less than the second preset value in multiple cut cell strings.

[0072] In some embodiments, after the cells with the print-through ratio greater than or equal to the second preset value in the cell string are cut, it further includes: connecting the cut cells with the print-through ratio greater than or equal to the second preset value to form a third reconnected cell string; and sending the third reconnected cell string to the gluing process. Although all cells in the third reconnected cell string need to be glued for a long time, compared to all cells in the gluing process needing a long gluing time, only the third reconnected cell string has a long gluing time, which can still improve the overall work efficiency of the gluing process, and thus is conducive to improving the overall manufacturing efficiency of the photovoltaic module.

[0073] It should be noted that the cells in the third reconnected cell string can be reconnected by the cells with the print-through ratio greater than or equal to the second preset value in multiple cut cell strings, so that the total number of cells in the third reconnected cell string meets the total number of cells required in a single cell string.

[0074] Figure 4Another photovoltaic module detection method provided by the embodiment of the present application corresponds to a flow chart.

[0075] Reference Figure 4 In some embodiments, if the missing printing ratios of all the cell pieces in the cell string are less than or equal to the first preset value, sending the cell string to the next process includes: obtaining a missing glue ratio corresponding to each solder strip according to the glue point image, the missing glue ratio being a ratio of the number of unqualified glue points corresponding to each solder strip to the total number of preset glue point positions corresponding to the solder strip.

[0076] If the missing glue ratio is less than or equal to a third preset value (corresponding to condition 4 in the above table), the cell string is sent to the next process; if the missing glue ratio is greater than the third preset value (corresponding to condition 5 in the above table), the cell string is sent to the glue supplement process. Figure 4 Figure 4 If the missing glue ratio is less than or equal to a third preset value (corresponding to condition 4 in the above table), the cell string is sent to the next process; if the missing glue ratio is greater than the third preset value (corresponding to condition 5 in the above table), the cell string is sent to the glue supplement process.

[0077] No matter whether the two-polarity grid lines on the cell piece are located on two surfaces of the cell piece or the two-polarity grid lines on the cell piece are located on the same side surface of the cell piece, if the missing glue ratio corresponding to any solder strip is less than or equal to the third preset value, the cell string can be sent to the next process; if the missing glue ratio corresponding to any solder strip is greater than the third preset value, the cell string needs to be sent to the glue supplement process.

[0078] That is, when the missing printing ratios of all the cell pieces in the cell string are less than or equal to the first preset value, it is also necessary to judge whether the number of glue points corresponding to each solder strip meets the requirement, and when the missing glue ratios corresponding to each solder strip are all less than the third preset value, it can be further ensured that the cell string will not have problems such as solder strip deviation or falling off in the subsequent process, thereby being conducive to improving the manufacturing yield of the photovoltaic module. Since the missing glue ratio of a single solder strip exceeds the third preset value, but the missing printing ratio of the cell piece is less than the first preset value, the time required for the cell string to supplement glue is short, and a large number of cell strings will not be accumulated in the glue supplement process, therefore, the missing printing ratio of the cell piece as a whole is first judged, and then the missing glue ratio corresponding to a single solder strip is judged, which is conducive to improving the manufacturing efficiency of the photovoltaic module.

[0079] ​In some embodiments, if the missing-glue ratio is greater than the third preset value, before the battery string is sent to the glue-filling process, the method further comprises: obtaining the total number of battery pieces corresponding to the solder strips with the missing-glue ratio greater than the third preset value in the battery string, if the total number of battery pieces corresponding to the solder strips with the missing-glue ratio greater than the third preset value is greater than or equal to 1 / 2 of the total number of battery pieces in the battery string, the battery string is sent to the repair process; if the total number of battery pieces corresponding to the solder strips with the missing-glue ratio greater than the third preset value is less than 1 / 2 of the total number of battery pieces in the battery string, the battery string is sent to the glue-filling process. Since the number of battery pieces or solder strips that need to be filled with glue in the battery string is large, it is also easy to cause a large number of battery strings to be accumulated in the glue-filling process, therefore, according to the number of battery pieces that need to be filled with glue in the battery string to further determine whether the battery string should enter the glue-filling process or the repair process, the manufacturing efficiency of the photovoltaic module can be further improved.

[0080] In some embodiments, the third preset value can be set to 1.5% to 2.5%, for example, it can be 1.5%, 1.6%, 1.8%, 2%, 2.2% or 2.5%, etc. The third preset value can be adjusted according to the length of the solder strip and the position of the glue point that can be set on the battery piece.

[0081] The method for detecting the photovoltaic module provided by the embodiments of the present application includes connecting the cell pieces through the solder strips and fixing the solder strips on the cell pieces through multiple adhesive points to form a cell string with no main grid structure, which is conducive to reducing the cost of silver paste, reducing light-shading loss, shortening the current transmission path, reducing the series resistance and improving the power of the photovoltaic module. First, the cell string is subjected to first image detection, and whether each cell piece in the cell string meets the preset requirements is determined according to the result of the first image detection. If at least one cell piece does not meet the preset requirements, the cell string is sent to a repair process. If all the cell pieces meet the preset requirements, the cell string is sent to a next process. The cell piece that does not meet the preset conditions or has defects in the cell string is determined in advance, and the cell string with the cell piece that does not meet the preset conditions is sent to the repair process, so that the problem of time and cost increase caused by the cell piece with defects entering the subsequent process and then being repaired can be avoided. Then, the cell string is subjected to second image detection to obtain the adhesive point image of each cell piece in the cell string, the corresponding missing printing ratio of each cell piece is obtained according to the adhesive point image, and it is determined based on the missing printing ratio that the cell string is to be sent to which process. For example, if the missing printing ratio of all the cell pieces in the cell string is less than or equal to a first preset value, the cell string is sent to the next process. If the missing printing ratio of at least one cell piece in the cell string is greater than or equal to a second preset value, the cell string is sent to the repair process. If the missing printing ratio of all the cell pieces in the cell string is less than the second preset value and the missing printing ratio of at least one cell piece is greater than the first preset value, the cell piece is sent to a glue supplementing process. When the missing printing ratio corresponding to the cell piece is greater than the first preset value, it indicates that the cell piece needs to be supplemented with glue. However, when the missing printing ratio of the cell piece is greater than the second preset value, it indicates that the cell piece needs to be supplemented with a large amount of glue. Therefore, the glue supplementing time of a single cell piece is relatively long, and if all the cell strings that need to be supplemented with glue are waiting in the glue supplementing process, a large number of cell strings will be accumulated in the glue supplementing process, thereby reducing the manufacturing efficiency of the photovoltaic module. Therefore, the cell string corresponding to the cell piece with the missing printing ratio between the first preset value and the second preset value is sent to the glue supplementing process, and the cell string corresponding to the cell piece with the missing printing ratio greater than the second preset value is sent to the repair process, so that different processes can be selected for different cell strings, the problem of a large number of cell strings queuing in the glue supplementing process can be avoided, the production efficiency of the photovoltaic module is improved, and the manufacturing cost is saved.

[0082] Those skilled in the art can understand that the above embodiments are specific embodiments for implementing the present application, and in actual applications, various changes can be made in form and details without departing from the spirit and scope of the present application. Any person skilled in the art can make various modifications and changes without departing from the spirit and scope of the present application, and therefore the protection scope of the present application should be subject to the range defined by the claims.

Claims

1. A method for testing photovoltaic modules, characterized in that, include: Solder ribbons are laid on the surface of the battery cells and the solder ribbons are fixed to the battery cells by multiple adhesive dots. Multiple battery cells are connected by the solder ribbons to form a battery string. A first image detection is performed on the battery string to obtain a detection image of each of the battery cells in the battery string; Based on the detected image, it is determined whether each of the battery cells in the battery string meets the preset conditions. If all the battery cells in the battery string meet the preset conditions, the battery string is sent to the next process. If at least one battery cell in the battery string does not meet the preset conditions, the battery string is sent to the rework process. A second image detection is performed on the battery string to obtain an image of the adhesive dots for each of the battery cells in the battery string; The missing print ratio for each battery cell is obtained based on the glue dot image. The missing print ratio is expressed as the ratio of the number of defective glue dots on each battery cell to the total number of preset glue dot positions on the battery cell. If the missing print ratio of all the battery cells in the battery string is less than or equal to a first preset value, then the battery string is sent to the next process. If the missing print ratio of at least one of the battery cells in the battery string is greater than the first preset value, and the missing print ratio of all the battery cells in the battery string is less than the second preset value, then the battery string is sent to the glue application process. If the missing print ratio of at least one of the battery cells in the battery string is greater than or equal to the second preset value, then the battery string is sent to the rework process.

2. The method for testing photovoltaic modules according to claim 1, characterized in that, If the missing printing ratio of all the battery cells in the battery string is less than or equal to the first preset value, the battery string is sent to the next process including: obtaining the missing glue ratio of each solder strip according to the glue dot image, wherein the missing glue ratio is the ratio of the number of defective glue dots corresponding to each solder strip to the total number of preset glue dot positions corresponding to the solder strip. If the glue shortage ratio is less than or equal to the third preset value, the battery string is sent to the next process; If the glue shortage ratio is greater than the third preset value, the battery string is sent to the glue replenishment process.

3. The method for testing photovoltaic modules according to claim 2, characterized in that, The third preset value is 1.5% to 2.5%.

4. The method for testing photovoltaic modules according to claim 1, characterized in that, If at least one of the battery cells in the battery string does not meet the preset condition, the battery string is sent to the rework process, including: Cut off the battery cells in the battery string that do not meet the preset conditions, and connect the remaining battery cells in the battery string to form a first recombinant battery string; The second image detection is performed on the first recombined battery string.

5. The method for testing photovoltaic modules according to claim 1, characterized in that, If the missing print ratio of at least one cell in the battery string is greater than or equal to the second preset value, sending the battery string to the rework process includes: Cut the battery cells in the battery string whose missing printing ratio is greater than or equal to the second preset value, and connect the remaining battery cells in the battery string to form a second recombinant battery string; If the missing print ratio of all the cells in the second recombined battery string is less than or equal to the first preset value, then the second recombined battery string is sent to the next process. If the missing print ratio of at least one cell in the second recombined battery string is greater than the first preset value, and the missing print ratio of all cells in the second recombined battery string is less than the second preset value, then the second recombined battery string is sent to the glue application process.

6. The method for testing photovoltaic modules according to claim 5, characterized in that, After cutting the battery cells in the battery string whose stencil ratio is greater than or equal to the second preset value, the method further includes: connecting multiple cut battery cells with a stencil ratio greater than or equal to the second preset value in series to form a third recombinant battery string; and sending the third recombinant battery string into the glue application process.

7. The method for testing photovoltaic modules according to claim 1, characterized in that, The solder ribbon is fixed to the battery cell by a plurality of adhesive dots, including: the adhesive dots being located on the surface of the solder ribbon away from the battery cell; and / or, the adhesive dots being located between the solder ribbon and the battery cell.

8. The method for testing photovoltaic modules according to claim 7, characterized in that, If the adhesive dot is located on the surface of the solder ribbon away from the battery cell, the defective adhesive dot includes the following: the surface of the solder ribbon has no adhesive dot.

9. The method for testing photovoltaic modules according to claim 7, characterized in that, If the adhesive dot is located between the solder strip and the battery cell, the defective adhesive dot includes the following situations: the diameter of the adhesive dot is smaller than the diameter of the solder strip; or, the distance between the adhesive dot and the solder strip is greater than 0.

10. The method for testing photovoltaic modules according to claim 1, characterized in that, The first preset value is 1.5% to 2.5%; The second preset value is 4% to 6%.

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