阅读说明：本技术 一种检测mwt光伏组件导电胶印刷的方法 (Method for detecting printing of MWT photovoltaic module conductive adhesive ) 是由 陈晓辉 张允良 顾群 吴仕梁 张凤鸣 于 2021-11-24 设计创作，主要内容包括：本发明公开了一种检测MWT光伏组件导电胶印刷的方法,通过光学相机以筛选出导电胶外观缺陷以及导电胶与绝缘层的相对位置不良等缺陷,通过视觉检测方法解决组件内部无法通过人工检测方法检测的不良问题,降低光伏组件降级或报废的几率,提高生产效率。(The invention discloses a method for detecting MWT photovoltaic module conductive adhesive printing, which screens out defects such as conductive adhesive appearance defect and poor relative position of conductive adhesive and an insulating layer through an optical camera, solves the problem that the interior of a module cannot be detected through a manual detection method through a visual detection method, reduces the degradation or scrapping probability of a photovoltaic module, and improves the production efficiency.)

1. A method for detecting MWT photovoltaic module conductive adhesive printing is characterized by comprising the following steps:

step 1, setting a transmission carrier plate state;

step 2, laying an integrated conductive back plate on the carrier plate arranged in the step 1;

step 3, printing conductive adhesive on the integrated conductive back plate;

step 4, laying an insulating layer on the integrated conductive back plate, wherein the insulating layer is provided with holes corresponding to the positions of the conductive adhesives;

step 5, scanning the insulating layer by using an optical linear scanning camera to detect the appearance state of the conductive adhesive and the relative position of the conductive adhesive and the insulating layer, and entering step 6 if the detection is qualified, or else, alarming by equipment to be manually adjusted;

step 6, paving a battery piece on the conductive adhesive of the conductive back plate which is qualified in detection, so that an electric path is formed between the battery piece and the conductive adhesive;

step 7, carrying out visual detection on the battery piece by using an optical linear scanning camera and an infrared laser light source to detect the internal structural state of the battery piece, and entering step 8 if the detection is qualified, or else, alarming to be adjusted;

and 8, paving EVA on the qualified battery piece to complete the manufacture of the photovoltaic module.

2. The method for detecting printing of conductive paste of an MWT photovoltaic module according to claim 1, characterized in that said step 3 is specifically: and tightly placing a printing screen on the integrated conductive back plate, and printing conductive adhesive on the integrated conductive back plate through preset holes of the printing screen.

3. The method for detecting printing of conductive paste of an MWT photovoltaic module according to claim 2, characterized in that said step 5 is specifically: and adopting a single or a plurality of optical linear scanning cameras to obtain the diameter of the conductive adhesive and the relative distance between the conductive adhesive and the hole wall of the opening of the insulating layer in the process that the carrier plate drives the conductive core plate and the insulating layer to move rapidly so as to judge whether the conductive adhesive is completely printed and whether the insulating layer is laid in the middle.

4. The method for detecting MWT photovoltaic module conductive adhesive printing according to claim 3, wherein if the diameter of the conductive adhesive is less than 1.5mm, the appearance state of the conductive adhesive is judged to be small adhesive dots or adhesive dots are missing, and the detection is unqualified; if the minimum value of the relative distance between the conductive adhesive and the wall of the opening hole of the insulating layer is 0, judging that the conductive adhesive is adhered to the edge of the opening hole of the insulating layer or the conductive adhesive is covered, and determining that the detection is unqualified.

5. The method for detecting printing of conductive paste of an MWT photovoltaic module according to claim 4, wherein the adjustment is specifically: when the appearance state of the conductive adhesive is judged to be small or missing, the adhesive is supplemented; when the conductive adhesive is judged to be adhered to the edge of the opening of the insulating layer or the conductive adhesive is covered, adjusting the position of the insulating layer; and if the unqualified conductive adhesive cannot be adjusted to be qualified, performing offline treatment.

6. The method of claim 5, wherein the optical linear scanning camera and transport carrier plate are kept in relative motion, and the camera captures a new line of pixels as the integrated conductive backplane moves past the optical linear scanning camera.

7. The method of claim 6, wherein the optical linear scanning camera is electrically connected to a vision processor, and the vision processor receives and stores each pixel line acquired by the camera and integrates all pixel line data to construct a 2D image.

8. The method for detecting printing of conductive paste of MWT photovoltaic module according to claim 1 or 7, characterized in that the visual detection method in step 7 is specifically: the surface of the battery piece is excited by an infrared light source, so that the battery piece automatically generates electricity to form a single-core electricity generating body, and the single-core electricity generating body is shot by an optical linear scanning camera.

9. The method for detecting printing of conductive paste of an MWT photovoltaic module according to claim 1 or 7, characterized in that the completion of the photovoltaic module fabrication is in particular: paving glass on the EVA to prepare a sample; then preheating the sample, fixing the sample by melting EVA, turning over and discharging; and finally, the photovoltaic module enters a laminating machine for lamination to complete the manufacture of the photovoltaic module.

Technical Field

The application relates to the technical field of solar photovoltaic modules, in particular to a method for detecting printing of an MWT photovoltaic module conductive adhesive.

Background

The MWT back contact photovoltaic module has the advantages that because the front side of the MWT back contact photovoltaic module is not provided with the main grid line, the positive electrode and the negative electrode are arranged on the back side of the cell piece, the shading loss of the front side is reduced, and the power of the module is improved; the conductive foil is used for replacing a welding strip, so that the series resistance and the working temperature of the assembly are reduced, the problems of stress, poor welding, micro hidden cracks and the like caused by high-temperature welding are avoided by adopting low-temperature conductive adhesive for welding, and the stability and the reliability of the assembly are improved; the method is suitable for ultrathin silicon wafers, is compatible with high-efficiency battery pieces of different processes such as MWT, IBC and the like, and further has wide application prospect.

At present, the manufacturing method of the back contact photovoltaic module mainly comprises the following steps: vacuum packaging is carried out by integrating a conductive core board, conductive adhesive, an insulating layer, a battery piece, EVA and glass in a laminating mode, and the printing state of all conductive adhesive dots cannot be accurately monitored in the existing process manufacturing flow; the relative position of the conductive adhesive and the insulating layer cannot be accurately monitored; it is impossible to accurately check whether all the glue dots are short of the conductive glue due to the clogging of the mesh.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides the method for detecting the printing of the conductive adhesive of the MWT photovoltaic module, which can detect the defects of the conductive adhesive, such as adhesive shortage, blocked adhesive points and the like, and improve the reliability of the product.

The invention discloses a method for detecting printing of a conductive adhesive of an MWT photovoltaic module, which comprises the following steps:

step 1, setting the state of a transmission carrier plate.

And 2, laying an integrated conductive back plate on the carrier plate arranged in the step 1.

And 3, printing conductive adhesive on the integrated conductive back plate.

And 4, paving an insulating layer on the integrated conductive back plate, wherein the insulating layer is provided with holes corresponding to the positions of the conductive adhesives.

And 5, scanning the insulating layer by using an optical linear scanning camera to detect the appearance state of the conductive adhesive and the relative position of the conductive adhesive and the insulating layer, and entering step 6 if the detection is qualified, or else, alarming by equipment to be manually adjusted.

And 6, paving a battery piece on the conductive adhesive of the conductive back plate which is qualified in detection, so that an electric path is formed between the battery piece and the conductive adhesive.

And 7, visually detecting the battery piece by using an optical linear scanning camera and an infrared laser light source to detect the internal structural state of the battery piece, entering the step 8 if the detection is qualified, and otherwise, alarming to be adjusted.

And 8, paving EVA on the qualified battery piece to complete the manufacture of the photovoltaic module.

Preferably, step 3 specifically comprises: and tightly placing a printing screen on the integrated conductive back plate, and printing the conductive adhesive on the integrated conductive back plate through preset holes of the printing screen.

Preferably, step 5 specifically comprises: and adopting a single or a plurality of optical linear scanning cameras to obtain the diameter of the conductive adhesive and the relative distance between the conductive adhesive and the hole wall of the opening of the insulating layer in the process that the carrier plate drives the conductive core plate and the insulating layer to move rapidly so as to judge whether the conductive adhesive is completely printed and whether the insulating layer is laid in the middle.

Preferably, if the diameter of the conductive adhesive is smaller than 1.5mm, judging that the appearance state of the conductive adhesive is small in adhesive dots or missing in adhesive dots, and determining that the conductive adhesive is unqualified in detection; if the minimum value of the relative distance between the conductive adhesive and the wall of the opening hole of the insulating layer is 0, judging that the conductive adhesive is adhered to the edge of the opening hole of the insulating layer or the conductive adhesive is covered, and determining that the detection is unqualified.

Preferably, the adjustment is specifically: when the appearance state of the conductive adhesive is judged to be small or missing, the adhesive is supplemented; when the conductive adhesive is judged to be adhered to the edge of the opening of the insulating layer or the conductive adhesive is covered, adjusting the position of the insulating layer; and if the unqualified conductive adhesive cannot be adjusted to be qualified, performing offline treatment.

Preferably, the optical linear scanning camera is kept in relative motion with the transport carrier, and the camera captures a new line of pixels as the integrated conductive backplane moves past the optical linear scanning camera.

Preferably, the optical linear scanning camera is electrically connected to the vision processor, and the vision processor receives and stores each pixel line acquired by the camera, and integrates all pixel line data to construct a 2D image.

Preferably, the visual inspection method in step 7 specifically comprises: the surface of the battery piece is excited by an infrared light source, so that the battery piece automatically generates electricity to form a single-core electricity generating body, and the single-core electricity generating body is shot by an optical linear scanning camera.

Preferably, the manufacturing of the photovoltaic module is completed by: paving glass on the EVA to prepare a sample; then preheating the sample, fixing the sample by melting EVA, turning over and discharging; and finally, the photovoltaic module enters a laminating machine for lamination to complete the manufacture of the photovoltaic module.

Compared with the prior art, the invention has the following advantages: the method for detecting the printing of the MWT photovoltaic module conductive adhesive has the following beneficial effects:

according to the invention, the adverse phenomena of conductive adhesive starvation, adhesive spot shielding and the like are solved through shooting detection of the optical camera, and the problem that the photovoltaic module is degraded or scrapped due to the fact that the potential defects cannot be detected in a manual detection mode by combining the optical camera with an infrared light source to detect the interior of the battery module is solved.

Drawings

In order to more clearly illustrate the technical solutions of the present invention patent, the drawings needed to be used in the present invention patent will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention patent, and other drawings can be obtained by those skilled in the art without inventive efforts.

FIG. 1 is a flow chart of an online detection method according to an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

As shown in fig. 1, the invention discloses a method for detecting conductive adhesive printing of an MWT photovoltaic module, which specifically comprises the following steps:

step 1, setting the state of a transmission carrier plate to enable the transmission carrier plate to be in a normal working state.

And 2, laying an integrated conductive back plate on the arranged carrier plate.

And 3, printing conductive adhesive on the integrated conductive back plate, wherein the conductive adhesive is free from loss during printing and cannot be covered by the insulating layer, the conductive adhesive is circular point-shaped adhesive during printing, and the specification of the circular surface of the conductive adhesive is more than or equal to 1.5 mm.

And 4, paving an insulating layer on the integrated conductive back plate, processing the insulating layer through opening, wherein the opening corresponds to the printing position of the conductive adhesive on the integrated conductive back plate, so that the conductive adhesive can be directly displayed through the opening of the insulating layer. Because the equipment for movably laying the insulating layer limits that the insulating layer laying process can not directly finish material drawing, namely directly shooting photos, and simultaneously because of the characteristics of the linear camera, the material drawing can be completely realized in the process of conveying the motion of the carrier plate, the linear camera is arranged in an idle area between the two processes of conveying the carrier plate and the relative motion of the linear camera, the beat of other processes is not influenced, and the on-line monitoring can be realized.

And 5, scanning the insulating layer by using a single or a plurality of optical linear scanning cameras to detect the appearance state of the conductive adhesive and the relative position of the conductive adhesive and the insulating layer.

During scanning, it is necessary to maintain relative motion between the optical linear scanning camera and the carrier plate, and the motion direction is usually along the conveyor belt of the carrier plate. When the integrated conductive back plate printed with the conductive adhesive and laid with the insulating layer moves to pass by the front of the camera, the camera acquires a new pixel line. The linear camera composes the collected pixel lines into an image, and forms a top view and a side view of the conductive paste according to the state of the pixel lines. The optical linear scanning camera is electrically connected with the vision processor and the image acquisition card, the optical linear scanning camera stores all the acquired pixel lines in the image acquisition card and sends the acquired pixel lines to the vision processor, and the stored pixel lines are integrated and reconstructed into a 2D image through the vision processor. The image acquisition process is good at acquiring images of discrete elements when the integrated conductive core board printed with the conductive adhesive and laid with the insulating layer moves rapidly, and can detect all side surfaces of the conductive adhesive.

Since line scan imagers can provide 500-8,000 pixel/line resolution, some can even keep up with the high line acquisition rate of 67,000 lines/second. The conductive paste is printed and then a less regular cylinder, and the line scan camera can also "unroll" the cylinders to capture their entire surface area. Meanwhile, the line scanning imaging technology is also suitable for some larger objects which need high-resolution imaging to realize accurate measurement and defect detection. These attributes make line scan cameras an ideal choice for surface inspection applications after back contact photovoltaic module conductive paste printing.

Because line scanning methods only need to look at a small portion of the target object to acquire each line, they do not require the target object to provide a large unobstructed field of view. For this reason, they are very suitable for field retrofitting or installation of installations with limited installation space.

And in the process that the carrier plate drives the conductive core plate and the insulating layer to move rapidly, calculating the diameter of the conductive adhesive and the relative distance between the conductive adhesive and the hole wall of the opening of the insulating layer. If the diameter of the conductive adhesive is smaller than 1.5mm, judging that the adhesive dots of the conductive adhesive are small or the adhesive dots are missing, and if the minimum value of the relative distance between the conductive adhesive and the wall of the hole of the insulating layer is 0, judging that the conductive adhesive is adhered to the edge of the hole of the insulating layer or the conductive adhesive is covered. Meanwhile, qualified adhesive dots are obtained when the diameter of the conductive adhesive is larger than or equal to 1.5mm and the minimum value of the relative distance between the conductive adhesive and the hole wall of the opening of the insulating layer is larger than 0, and if all the adhesive dots of the conductive adhesive on one integrated conductive back plate are qualified adhesive dots, the step 6 is carried out; otherwise, the equipment automatically alarms, and the corresponding checking and glue supplementing or the position of the insulating layer is manually adjusted until all the conductive glue points are qualified glue points, or the line is off-line processed.

And 6, paving a battery piece on the conductive adhesive of the qualified conductive back plate.

And 7, visually detecting the battery piece by using a camera and a light source so as to detect the internal structural state of the battery piece. The surface of the battery piece is excited by an infrared light source, so that the battery piece automatically generates electricity to form a single-core power generation body, and a special camera, namely an optical linear scanning camera, is used for shooting and taking materials to determine internal defects. The internal defects mainly refer to some poor items of the battery plate, such as: and some abnormal items with appearance which can not be directly detected by naked eyes, such as hidden cracks, black spots, dark spots, broken grids and the like.

In the prior art, a thermal imager is often adopted to collect an infrared thermal image of a battery piece to which reverse bias is applied, and the leakage potential of the battery piece is judged according to the collected infrared thermal image, but in the detection method, an independent and complete individual is formed after the assembly is packaged, and then reverse current can be applied to the battery piece to finish material collection. Several independent individuals are not packaged before, and cannot be detected by the method. The method disclosed by the patent directly uses the infrared light source to excite the plurality of batteries to generate electricity, and can realize one-time material taking.

And 8, paving EVA on the battery piece qualified in detection, paving glass on the EVA, and preparing a sample. The samples were preheated by melting the EVA to fix the sample and turning over the discharge. And after discharging, the material enters a laminating machine to be laminated, and then the photovoltaic module is manufactured.

The above description is only exemplary of the present application and should not be taken as limiting the present application, as any modification, equivalent replacement, or improvement made within the spirit and principle of the present application should be included in the protection scope of the present application.