A novel processing method for solar thermoelectric integrated PVT modules

Abstract

This invention relates to a novel processing method for solar-thermal-electric integrated PVT modules. Utilizing existing photovoltaic modules, the method involves laminating a frameless solar photovoltaic module with a heat exchanger to form a semi-finished PVT module. Two inspection and two rework processes at the frameless photovoltaic module and heat exchanger stages quickly identify process abnormalities, preventing batches of defective products from flowing into subsequent processes. After lamination, an EL (Elastic Elasticity) test is performed again for rapid and accurate detection of EL defects in the semi-finished PVT module, significantly improving the yield rate of the finished PVT module. Qualified products are then fitted with insulation boards, back panels, frames, and battery boxes, and the battery boxes are tested. Finally, the heat exchanger is filled with protective gas, and the module is cured to form the finished PVT module product. This invention improves upon existing solar photovoltaic module processing technology by reducing pre-processing steps in the production of solar PVT modules, while also providing a new avenue for the application of photovoltaic modules.

Description

Technical Field

[0001] This invention relates to the field of solar photovoltaic and solar thermal integrated utilization technology, specifically to a novel processing method for solar thermal power integrated PVT modules. Background Technology

[0002] Energy and environmental issues are critical to my country's national economy, people's livelihood, and national security. In recent years, my country's total energy consumption has been rising continuously, while environmental pressures have also been increasing. Solar energy, as a high-quality, clean, and renewable energy source, offers an effective way to address energy shortages and environmental pollution compared to traditional fossil fuels through efficient and in-depth development and utilization. Currently, photovoltaic (PV) and solar thermal technologies are widely used in the building sector. However, existing solar thermal and PV technologies suffer from limited component capacity and low system energy conversion efficiency, failing to meet the need for buildings to simultaneously utilize both PV and solar thermal systems within limited space.

[0003] In recent years, research on solar photovoltaic and solar thermal integration technology has increased. Solar photovoltaic and solar thermal integration technology is a solar energy utilization technology that integrates photovoltaic power generation and low-temperature heat utilization. It integrates traditional solar thermal modules and photovoltaic modules into one unit to form a PVT module, realizing cogeneration on the same module. By laying fluid channels on the back of the photovoltaic module, the heat generated by the cells is carried away, reducing the temperature of the cells and improving the photoelectric conversion efficiency of the photovoltaic module. The dissipated heat is effectively collected and utilized, thereby improving the comprehensive utilization efficiency of solar energy.

[0004] The existing domestic solar photovoltaic module production technology is relatively mature and complete. How to process existing photovoltaic modules into solar PVT modules can reduce the pre-processing procedures in the production of solar PVT modules and provide a new way for the application of photovoltaic modules. Summary of the Invention

[0005] To address the above problems, this invention proposes a novel method for processing solar-thermal-electric integrated PVT modules, utilizing existing photovoltaic modules to process solar-thermal-electric integrated PVT modules.

[0006] To achieve the above objectives, the following technical solution is adopted: a novel solar thermal-electric integrated PVT module processing method, comprising the following steps:

[0007] S1. Perform appearance and EL inspection on frameless photovoltaic modules, rework defective products, and re-perform appearance and EL inspection after rework;

[0008] S2. For qualified frameless photovoltaic modules, an adhesive film is applied according to the size of their backsheet;

[0009] S3. Perform visual inspection and pressure test on the heat exchanger. For defective products, rework them and perform visual inspection and pressure test again after rework.

[0010] S4. The qualified heat exchanger is laid on the encapsulant film of the frameless photovoltaic module;

[0011] S5. The laid frameless photovoltaic modules are laminated to form semi-finished PVT modules;

[0012] S6. Perform secondary EL testing on semi-finished PVT components, rework defective products, and perform secondary EL testing again after rework;

[0013] S7. Qualified products shall be fitted with insulation boards, back panels, and frames;

[0014] S8. Qualified products are installed in battery boxes and subjected to insulation resistance test, DC withstand voltage test and power test;

[0015] S9. The heat exchanger in the qualified product is filled with protective gas and the component is cured to finally form a PVT component product.

[0016] A further technical solution is that the melting point of the adhesive film in step S2 is 10-20°C lower than the melting point of the EVA adhesive film in the frameless photovoltaic module.

[0017] A further technical solution is that the lamination process in step S5 is completed in a dual-chamber laminating device. This process includes a first lamination stage, a second lamination stage, and a third lamination stage. The lamination temperature in all three stages is the melting point temperature of the adhesive film. In the first lamination stage, the pressure in both the upper and lower chambers of the dual-chamber laminating device is maintained at -0.1 MPa for 6 minutes. In the second lamination stage, the pressure in the upper chamber of the dual-chamber laminating device is adjusted from -0.1 MPa to 0.1 MPa, while the pressure in the lower chamber is maintained at -0.1 MPa for 4 minutes. In the second lamination stage, the pressure in the upper chamber of the dual-chamber laminating device is maintained at 0.1 MPa, while the pressure in the lower chamber is maintained at -0.1 MPa for 4 minutes.

[0018] A further technical solution is that in step S5, the semi-finished PVT component, insulation board, back panel and frame are bonded together with an adhesive, which is a room temperature curing silicone adhesive.

[0019] A further technical solution is that the protective gas charged in step S7 is nitrogen, and the charging gas pressure is less than 0.5 MPa.

[0020] A further technical solution is that the size of the heat exchanger is the same as the size of the film.

[0021] A further technical solution is that the heat exchanger is made of brazed aluminum plate, stainless steel plate or copper plate.

[0022] A further technical solution is that the heat exchanger has a single-sided blown flow channel structure or a double-sided blown flow channel structure, and the flow channel structure in the heat exchanger is arranged in a honeycomb, serpentine or mesh pattern.

[0023] A further technical solution is to spray an epoxy resin coating with a thickness of 60-100μm onto the surface of the heat exchanger.

[0024] The beneficial effects of this invention are as follows: This invention utilizes solar PVT module manufacturing technology based on existing solar photovoltaic module processing technology, reducing pre-processing steps in the production of solar PVT modules and providing a new avenue for the application of photovoltaic modules. This invention forms solar PVT modules by laminating frameless solar photovoltaic modules with heat exchangers. Two inspection and two rework processes, involving both the frameless photovoltaic modules and the heat exchanger, can quickly detect process abnormalities, preventing batches of defective products from flowing into subsequent processes. A second EL inspection after lamination allows for rapid and accurate detection of EL defects in semi-finished PVT modules, significantly improving the yield rate of finished PVT modules, thereby reducing the cost of mass production and increasing production efficiency. Attached Figure Description

[0025] Figure 1 This is a process flow diagram of the processing method of the present invention;

[0026] Figure 2 This is a hierarchical structure of a solar thermal power integrated PVT module.

[0027] As shown in the figure: 1. Adhesive film layer; 2. Adhesive film layer; 3. Heat exchanger layer; 4. First adhesive layer; 5. Insulation layer; 6. Second adhesive layer; 7. Backsheet layer; 101. Glass layer; 103. Photovoltaic cell layer; 104. TPT backsheet; 1021. First adhesive film layer; 1022. Second adhesive film layer. Detailed Implementation

[0028] The present invention will be further described below with reference to embodiments. The description of the embodiments below is only for the purpose of helping to understand the present invention. It should be noted that those skilled in the art can make several modifications to the present invention without departing from the principle of the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention. Example

[0029] This embodiment describes the fabrication of a solar thermal-electric integrated PVT module hierarchical structure, such as... Figure 2As shown, the module includes a frameless photovoltaic module layer 1, an encapsulant film layer 2, a heat exchanger layer 3, a first adhesive layer 4, an insulation layer 5, a second adhesive layer 6, and a backsheet layer 7. The heat exchanger has the same dimensions as the encapsulant film. After stacking these layers, a battery box and frame are installed to form a solar PVT module product. The frameless photovoltaic module uses existing frameless solar photovoltaic modules. The module's layer structure includes a glass layer 101, a first encapsulant film layer 1021, a photovoltaic cell layer 103, a second encapsulant film layer 1022, and a TPT backsheet 104. In this example, the EVA encapsulant film used in the first encapsulant film layer 1021 and the second encapsulant film layer 1022 has a melting point of 140℃. Therefore, the encapsulant film used in the solar PVT module in this example is of a higher quality than the first encapsulant film layer 1021 and the second encapsulant film layer 1022. The EVA film used in layer 1022 has a melting point 10-20℃ lower, which ensures that the first film layer 1021 and the second film layer 1022 will not melt during the lamination process of the solar PVT module in this example. The heat exchanger used in this example can be made of brazed aluminum plate, stainless steel plate or copper plate, and adopts a single-sided blown flow channel structure or a double-sided blown flow channel structure. The flow channel structure in the heat exchanger is arranged in a honeycomb, serpentine or mesh pattern, and the surface of the heat exchanger is coated with epoxy resin with a thickness of 60-100μm.

[0030] The following describes a novel processing method for solar thermal-electric integrated PVT modules, including the following specific steps:

[0031] S1. At the loading station, the frameless photovoltaic modules are transferred to the assembly line workbench. The frameless photovoltaic modules with the TPT backsheet 104 facing up are transported to the EL testing equipment. When appearance defects or EL defects are detected, the defective products are transferred to the rework station for rework. After rework, the appearance inspection and EL inspection processes are carried out again. The qualified products are transferred to the film cutting and loading station.

[0032] S2. When the film cutting and feeding station receives the frameless photovoltaic module, it feeds the film according to the size of the TPT backplate 104 of the frameless photovoltaic module and applies the film to the TPT backplate 104 of the frameless photovoltaic module.

[0033] S3. At the loading station, the heat exchanger is transported to the heat exchanger inspection station for appearance inspection and pressure test. If the appearance or pressure is not good, the defective product is sent to the rework station for rework. After rework, the appearance inspection and pressure test are carried out again. The qualified product is sent to the film cutting and loading station.

[0034] S4. When the film cutting and feeding station receives the heat exchanger, it lays the heat exchanger on the film of the TPT backsheet 104 of the frameless photovoltaic module.

[0035] S5. After installation, the frameless photovoltaic modules are transported to the lamination station for lamination. The lamination station uses a dual-chamber lamination equipment. The lamination process includes a first lamination stage, a second lamination stage, and a third lamination stage. The lamination temperature in all three stages is controlled between 120 and 130°C. In the first lamination stage, the pressure in both the upper and lower chambers of the dual-chamber lamination equipment is maintained at -0.1 MPa for 6 minutes. In the second lamination stage, the pressure in the upper chamber is adjusted from -0.1 MPa to 0.1 MPa, while the pressure in the lower chamber is maintained at -0.1 MPa for 4 minutes. In the third lamination stage, the pressure in the upper chamber is maintained at 0.1 MPa, while the pressure in the lower chamber is maintained at -0.1 MPa for 4 minutes. After the three lamination stages are completed, a semi-finished PVT module is formed.

[0036] S6. The semi-finished PVT components are sent to the secondary EL inspection station for secondary EL inspection. If appearance defects or EL defects are detected, the defective products are sent to the rework station for rework. After rework, the secondary EL inspection process is carried out again. The qualified products are sent to the glue application station.

[0037] S7. At the gluing station, the insulation board is glued to the heat exchanger of the semi-finished PVT module, the back sheet is glued to the insulation board, and then it is conveyed to the gluing frame station to apply glue to the outer frame of the semi-finished PVT module and install the frame. After completion, the semi-finished PVT module is conveyed to the battery box station.

[0038] S8. Install battery boxes on the semi-finished PVT modules and perform insulation resistance test, DC withstand voltage test and power test. The semi-finished PVT modules that pass the test are transferred to the gas filling station.

[0039] S9. Nitrogen gas is injected into the heat exchanger of the semi-finished PVT module as a protective gas. The gas pressure is less than 0.5 MPa. The module is then cured to form the final PVT module product.

[0040] in,

[0041] In step S1, the outer surface of the frameless photovoltaic modules is inspected to ensure it is clean and tidy, and that there is no damage to the glass or backsheet. Only products without any abnormalities can be loaded.

[0042] In step S3, the pressure test requirements for the heat exchanger are as follows: when the heat exchange medium is water or antifreeze, the pressure test pressure should not be less than 1.7 MPa; when the heat exchange medium is refrigerant, the pressure test pressure should not be less than 2.5 MPa. Additionally, when the working medium in the heat exchanger is refrigerant, the first adhesive layer 4 and the insulation layer 5 are omitted from the PVT module's layered structure; refrigerant-type solar PVT modules do not require insulation.

[0043] In steps S1 and S6, the EL inspection criteria for qualified products are: no microcracks, no fragments, no broken grids, no slip lines, no open welds, and no visible or hidden defects in the photovoltaic module cells; the cells are evenly arranged without misalignment. During the first EL inspection, the module code is simultaneously collected and transmitted to the production management operating system. During both EL inspections, modules with defects are coded and marked. During inspection, module images are acquired and sent to the production management operating system. The production management system transmits rework information to the corresponding rework station according to the rework plan. Rework information includes, but is not limited to: module code, module image, and rework method information.

[0044] In step S5, after lamination and processing, a semi-finished PVT module is formed. The adhesion strength between the adhesive film and the frameless photovoltaic module is ≥30 N / cm, and the adhesion strength between the film and the heat exchanger is ≥40 N / cm. The degree of crosslinking of the adhesive film after lamination is ≥80%.

[0045] In step S7, the requirements for applying adhesive to the frame are as follows: the allowable difference between the two diagonals of the frame is within 3‰ of the theoretical diagonal size; the dimensional tolerance is ±1mm; the frame arc is less than or equal to 0.8‰ of the frame length; the amount of adhesive applied to the frame is ≥ 1 / 2 of the groove depth; the length of the missing adhesive on the end face is ≤ 5mm; there is no silicone overflow on the front of the module; the adhesive overflow on the back is uniform, without adhesive spots or missing adhesive; and the depth of missing adhesive on the front of the module is ≤ 2mm.

[0046] In step S8, the battery box installation requirements are as follows: the battery box must be firmly and upright, the polarity markings must be correct, the lead plug must be firmly inserted into the socket, and it must be plugged in or soldered firmly. The cover must be tightly fastened to the box body, and the rubber ring must not be exposed. The cover and the box body must be flush, and the cover clips must not be warped or uneven. The cover cannot be opened by hand without tools. The potting compound must completely cover the live parts inside the junction box without affecting the cover fastening. The surface of the potting compound must be flat, free of air bubbles, and free of unevenness.

[0047] The testing requirements for insulation resistance, DC withstand voltage, and power are as follows: For insulation withstand voltage performance, the module's insulation resistance should be no less than 40 MΩ·m², and the leakage current ≤ 50 µA. A DC voltage equal to the sum of 1000 V and twice the maximum system voltage is applied between the positive and negative terminals of the module for 1 minute. The module should show no insulation breakdown or surface cracking. For power testing, an IV tester acquires IV curve data via a data acquisition unit, and computer software is used for data analysis and processing to assess whether the module's maximum power point meets the requirements for qualified products.

Claims

1. A novel method for processing solar thermoelectric integrated PVT modules, characterized in that, Includes the following steps, S1. Perform appearance and EL inspection on frameless photovoltaic modules, rework defective products, and re-perform appearance and EL inspection after rework; S2. For qualified frameless photovoltaic modules, an adhesive film is applied according to the size of their backsheet; S3. Perform visual inspection and pressure test on the heat exchanger. For defective products, rework them and perform visual inspection and pressure test again after rework. S4. The qualified heat exchanger is laid on the encapsulant film of the frameless photovoltaic module; S5. The laid frameless photovoltaic modules are laminated to form semi-finished PVT modules; S6. Perform secondary EL testing on semi-finished PVT components, rework defective products, and perform secondary EL testing again after rework; S7. Qualified products shall be fitted with insulation boards, back panels, and frames; S8. Qualified products are installed in battery boxes and subjected to insulation resistance test, DC withstand voltage test and power test; S9. The heat exchanger in the qualified product is filled with protective gas and the component is cured to finally form a PVT component product.

2. The processing method according to claim 1, characterized in that, The melting point of the adhesive film in step S2 is 10-20°C lower than that of the EVA adhesive film in the frameless photovoltaic module.

3. The processing method according to claim 2, characterized in that, The lamination process in step S5 is completed in a dual-chamber laminating equipment. This process includes a first lamination stage, a second lamination stage, and a third lamination stage. The lamination temperature in all three stages is the melting point temperature of the adhesive film. In the first lamination stage, the pressure in both the upper and lower chambers of the dual-chamber laminating equipment is maintained at -0.1 MPa for 6 minutes. In the second lamination stage, the pressure in the upper chamber of the dual-chamber laminator is adjusted from -0.1 MPa to 0.1 MPa, while the pressure in the lower chamber remains at -0.1 MPa for 4 minutes. In the first lamination stage of the second lamination stage, the pressure in the upper chamber of the dual-chamber laminator remains at 0.1 MPa, while the pressure in the lower chamber remains at -0.1 MPa for 4 minutes.

4. The processing method according to claim 3, characterized in that, In step S7, the semi-finished PVT component, insulation board, back panel, and frame are bonded together with an adhesive, which is a room-temperature curing silicone adhesive.

5. The processing method according to claim 4, characterized in that, The protective gas used in step S9 is nitrogen, and the gas pressure is less than 0.5 MPa.

6. The processing method according to any one of claims 1-5, characterized in that, The dimensions of the heat exchanger are the same as those of the film.

7. The processing method according to any one of claims 6, characterized in that, The heat exchanger is made of brazed aluminum plate, stainless steel plate or copper plate.

8. The processing method according to any one of claims 7, characterized in that, The heat exchanger is a single-sided blown flow channel structure or a double-sided blown flow channel structure, and the flow channel structure in the heat exchanger is arranged in a honeycomb, serpentine or mesh pattern.

9. The processing method according to any one of claims 8, characterized in that, The heat exchanger surface is coated with epoxy resin with a thickness of 60-100 μm.

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