A photovoltaic module product structure with high-strength stainless steel frame and backsheet

Abstract

This application relates to the field of photovoltaic power generation technology, and provides a photovoltaic module product structure with a high-strength stainless steel frame and backsheet. The structure includes a glass module, a cell layer disposed below the glass module, a stainless steel corrugated backsheet disposed below the cell layer, and stainless steel frames respectively disposed on the outer sides of the long sides of the glass module. The long edges of the stainless steel corrugated backsheet extend upwards to form connecting portions. The inner side of the stainless steel frame has a welding portion that welds to the connecting portions, thereby welding the stainless steel frame and the connecting portions of the stainless steel corrugated backsheet together. The short edges of the stainless steel corrugated backsheet extend upwards and bend inwards to form short edge guards, which are located on the outer sides of the short sides of the glass module. The glass module and the stainless steel corrugated backsheet are bonded together with structural adhesive. This achieves an integrated high-strength structural improvement of the photovoltaic module frame and backsheet.

Description

Technical Field

[0001] This invention belongs to the field of photovoltaic power generation technology, specifically relating to a photovoltaic module product structure with a high-strength stainless steel frame and backplate. Background Technology

[0002] In the field of photovoltaic power generation, the structural strength and corrosion resistance of photovoltaic modules are key factors determining their service life in harsh environments. Especially in coastal areas with high wind pressure or high salt spray environments, traditional photovoltaic modules face two major challenges:

[0003] Limitations of existing strength enhancement solutions: Traditional solutions improve wind resistance by using double-glass modules with aluminum reinforcing ribs, but the aluminum profiles are not strong and stiff enough, resulting in significant deflection of the modules under high wind pressure and an increased risk of microcracks in the cells; in addition, aluminum has limited corrosion resistance and is prone to oxidation in coastal environments, which shortens the life of the modules.

[0004] Defects in frame connection and sealing: Traditional module frames and glass modules rely on structural adhesive for bonding, requiring the design of overflow channels to prevent adhesive from overflowing and contaminating the surface. This not only increases the complexity of the process, but also the curing time of the structural adhesive affects production efficiency. In addition, the use of frame profiles on all four sides of the module results in structural redundancy and higher material costs.

[0005] While existing technologies have explored individual improvements to frame materials (such as stainless steel) or back panel structures (such as corrugated structures), there is still no technical solution that welds a stainless steel frame to a stainless steel corrugated back panel to form a synergistic load-bearing structure, or replaces the traditional short frame with a short edge protector on the back panel. In particular, how to simplify the frame structure and solve the problem of sealant overflow while improving overall rigidity remains a pressing technical challenge in this field. Summary of the Invention

[0006] This application provides a rapid assembly process for photovoltaic module frames, aiming to address the shortcomings of existing technologies. While there have been attempts to improve frame materials (such as stainless steel) or backsheet structures (such as corrugated structures), there is still no technical solution that welds a stainless steel frame and a stainless steel corrugated backsheet to form a synergistic load-bearing structure, and replaces the traditional short frame with a short edge protector on the backsheet. In particular, how to simplify the frame structure and solve the problem of sealant overflow while improving overall rigidity remains a pressing technical challenge in this field.

[0007] In one aspect, this application provides a photovoltaic module product structure with a high-strength stainless steel frame and backsheet, including a glass module, a cell layer disposed below the glass module, a stainless steel corrugated backsheet disposed below the cell layer, and stainless steel frames disposed on the outer sides of the long sides of the glass module respectively.

[0008] The long edges of the two sides of the stainless steel corrugated back panel extend upward to form a connecting part. The inner side of the stainless steel frame has a welding part that is welded to the connecting part, thus welding the stainless steel frame and the connecting part of the stainless steel corrugated back panel together. The short edges of the two sides of the stainless steel corrugated back panel extend upward and bend inward to form short edge guards, which are located on the outer sides of the short edges of the glass assembly. The glass assembly and the stainless steel corrugated back panel are bonded together with structural adhesive. A silicone strip is provided between the stainless steel frame and the side of the glass assembly, and the silicone strip is snapped between the stainless steel frame and the glass assembly to compress and seal the glass assembly.

[0009] The stainless steel corrugated back plate is provided with a corrugated structure, which extends along the long side of the glass assembly; the stainless steel frame is welded to the stainless steel corrugated back plate to form an integral structure.

[0010] In some embodiments, the inner side of the stainless steel frame is provided with a protruding welding boss along the length direction as the welding part, and the connecting part of the stainless steel corrugated back plate is provided with a welding plane adapted to the welding boss. The welding boss and the welding plane are fixedly connected by continuous welding or intermittent welding, so that the stainless steel frame and the stainless steel corrugated back plate form a rigid connection structure in the long side direction.

[0011] In some embodiments, the short edge of the stainless steel corrugated back plate extends upward to a height greater than or equal to the thickness of the glass assembly, and the extended portion is bent inward to form a protective edge plane that fits against the short side of the glass assembly. The width of the protective edge plane covers a predetermined protection area of ​​the short edge of the glass assembly.

[0012] In some embodiments, a structural adhesive layer is applied to the edge and / or center area of ​​the upper surface of the stainless steel corrugated back panel, the thickness of the structural adhesive layer being 0.5 mm to 2 mm, and the glass assembly is bonded to the stainless steel corrugated back panel through the structural adhesive layer, the application area of ​​the structural adhesive layer avoiding the corrugated groove area of ​​the stainless steel corrugated back panel.

[0013] In some embodiments, the stainless steel frame and the stainless steel corrugated back plate are made of stainless steel material, wherein the yield strength of the stainless steel material is greater than or equal to 205 MPa and the tensile strength is greater than or equal to 520 MPa.

[0014] In some embodiments, the inner side of the stainless steel frame is provided with a slot with a trapezoidal or rectangular cross section, and the outer side of the silicone strip is provided with a snap-fit ​​protrusion adapted to the slot. The silicone strip is embedded in the slot through the snap-fit ​​protrusion, and the inner side of the silicone strip is tightly fitted with the side of the glass assembly to form an elastic compression sealing structure. The height of the silicone strip is greater than the gap between the stainless steel frame and the side of the glass assembly.

[0015] In some embodiments, the corrugated structure is a continuous wavy or trapezoidal protrusion, the spacing between adjacent corrugated protrusions is 10 mm to 50 mm, the height of the corrugated protrusions is 5 mm to 15 mm, and the extension direction of the corrugated structure is consistent with the long side direction of the glass assembly.

[0016] In some embodiments, the stainless steel frame and the stainless steel corrugated back plate are welded to form a rigid frame. The stiffness of the long side of the frame is improved compared with that of traditional aluminum frame components. When the photovoltaic module is subjected to wind pressure load, the stainless steel frame and the stainless steel corrugated back plate work together to bear bending stress.

[0017] In some embodiments, a sealant layer is provided between the short side guard of the stainless steel corrugated back plate and the short side of the glass assembly. The sealant layer is applied to the contact area between the guard plane and the short side of the glass assembly, and the thickness of the sealant layer is 0.3 mm to 1 mm, replacing the sealing structure of the traditional short frame.

[0018] In some embodiments, the outer surface of the stainless steel frame is provided with an anti-corrosion coating, which is an epoxy resin coating or a polyvinylidene fluoride coating, and the thickness of the coating is 20 micrometers to 50 micrometers. The corrugated structure surface of the stainless steel corrugated back plate is simultaneously passivated or coated with an anti-corrosion coating.

[0019] In existing technologies, the application of stainless steel in photovoltaic modules is limited to localized corrosion-resistant components (such as screws and connectors), and has never involved a structural design that welds the stainless steel frame to the corrugated backsheet as a single unit. Traditional corrugated backsheets serve only as encapsulation materials, without providing structural reinforcement, and there is no technological concept of using short-side bending of the backsheet to form a protective edge to replace the short frame. Furthermore, the solution of using silicone strips to replace structural adhesive sealing solves the problems of traditional adhesive overflow and long curing times, and this sealing structure is designed in conjunction with the welded frame.

[0020] The core innovation of this invention lies in the dual breakthroughs in material selection and structural design: At the material level, it abandons traditional aluminum frames and aluminum reinforcing ribs, using high-strength stainless steel as both the frame and back panel material. Leveraging the excellent strength and corrosion resistance of stainless steel, it fundamentally improves component performance. At the structural level, through the integrated welding design of the stainless steel frame and corrugated back panel, a rigid frame is formed. The corrugated structure enhances the load-bearing capacity of the back panel, short-side edge protection simplifies the number of frames, and silicone strip sealing optimizes the production process. These technical features work together to achieve multiple technical effects of "strength enhancement, structural simplification, and process optimization," rather than simply replacing materials or adding components.

[0021] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0022] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a structural schematic diagram of a photovoltaic module product structure with a high-strength stainless steel frame and backplate provided in an embodiment of this application;

[0024] Figure 2 yes Figure 1 A magnified view of part A in the diagram.

[0025] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Detailed Implementation

[0026] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0027] The flowchart shown in the attached diagram is for illustrative purposes only and does not necessarily include all content and operations / steps, nor does it necessarily have to be performed in the order described. For example, some operations / steps can be broken down, combined, or partially merged, so the actual execution order may change depending on the actual situation.

[0028] It should be understood that, in order to clearly describe the technical solutions of the embodiments of the present invention, the terms "first" and "second" are used in the embodiments of the present invention to distinguish identical or similar items with essentially the same function and effect. Those skilled in the art will understand that the terms "first" and "second" do not limit the quantity or execution order, and the terms "first" and "second" are not necessarily different.

[0029] It should be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of the application. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0030] It should also be understood that the term “and / or” as used in this application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0031] The following detailed description of some embodiments of this application is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0032] In the field of photovoltaic power generation, the structural strength and corrosion resistance of photovoltaic modules are key factors determining their service life in harsh environments. Especially in coastal areas with high wind pressure or high salt spray environments, traditional photovoltaic modules face two major challenges:

[0033] Limitations of existing strength enhancement solutions: Traditional solutions improve wind resistance by using double-glass modules with aluminum reinforcing ribs, but the aluminum profiles are not strong and stiff enough, resulting in significant deflection of the modules under high wind pressure and an increased risk of microcracks in the cells; in addition, aluminum has limited corrosion resistance and is prone to oxidation in coastal environments, which shortens the life of the modules.

[0034] Defects in frame connection and sealing: Traditional module frames and glass modules rely on structural adhesive for bonding, requiring the design of overflow channels to prevent adhesive from overflowing and contaminating the surface. This not only increases the complexity of the process, but also the curing time of the structural adhesive affects production efficiency. In addition, the use of frame profiles on all four sides of the module results in structural redundancy and higher material costs.

[0035] While existing technologies have explored individual improvements to frame materials (such as stainless steel) or back panel structures (such as corrugated structures), there is still no technical solution that welds a stainless steel frame to a stainless steel corrugated back panel to form a synergistic load-bearing structure, or replaces the traditional short frame with a short edge protector on the back panel. In particular, how to simplify the frame structure and solve the problem of sealant overflow while improving overall rigidity remains a pressing technical challenge in this field.

[0036] To resolve the above issues, please refer to [link / reference]. Figure 1 and Figure 2 This application provides a photovoltaic module product structure with a high-strength stainless steel frame and backsheet, including a glass module, a cell layer disposed below the glass module, a stainless steel corrugated backsheet disposed below the cell layer, and stainless steel frames respectively disposed on the outer sides of the long sides of the glass module; the two long sides of the stainless steel corrugated backsheet extend upward to form connecting portions, and the inner side of the stainless steel frame is provided with welding portions that are welded to the connecting portions, thereby welding the stainless steel frame and the connecting portions of the stainless steel corrugated backsheet together; the two sides of the stainless steel corrugated backsheet... The short side edges extend upwards and bend inwards to form short side guards, which are located on the outer sides of the short sides of the glass assembly. The glass assembly and the stainless steel corrugated back plate are bonded together with structural adhesive. A silicone strip is provided between the stainless steel frame and the side of the glass assembly, and the silicone strip is snapped between the stainless steel frame and the glass assembly to compress and seal the glass assembly. The stainless steel corrugated back plate is provided with a corrugated structure, which extends along the long side of the glass assembly. The stainless steel frame and the stainless steel corrugated back plate are welded together to form an integral structure.

[0037] Specifically, the photovoltaic module product structure provided by this invention breaks through the strength and corrosion resistance bottlenecks of traditional photovoltaic modules through material innovation and structural integration design. The glass module, as the outer protective component, withstands external loads (such as wind pressure and snow accumulation), has a light transmittance of ≥90%, a thickness typically of 3.2mm~5mm, and is made of low-iron tempered glass. The solar cell layer is located below the glass module and consists of multiple solar cells connected in series / parallel via solder ribbons, with the surface covered by an EVA film (ethylene-vinyl acetate copolymer) for encapsulation and fixation.

[0038] Stainless steel corrugated back panels replace traditional organic back panels (such as TPT and PET), using stainless steel sheets with a thickness of 1.0mm to 2.0mm. Their core features are:

[0039] The corrugated structure features continuous wavy or trapezoidal protrusions along the long side of the glass assembly (i.e., the length of the assembly), with a protrusion height of 5mm to 15mm and a spacing of 10mm to 50mm. The corrugated structure enhances the bending stiffness of the back panel.

[0040] Connecting part and short side guard: The long side edges on both sides extend vertically upwards by 10mm~20mm to form a "connecting part" for welding with the stainless steel frame; the short side edges on both sides first extend upwards (height ≥ glass component thickness), and then bend inwards by 90° to form a "short side guard", the guard width covers a 5mm~10mm protective area of ​​the short side edge of the glass (replacing the traditional short frame).

[0041] The stainless steel frame uses the same stainless steel profile as the back panel, with an "L" or "U" shaped cross-section, and is only located on the outer sides of the two long sides of the glass assembly (traditional assemblies have frames on all four sides). Raised "welding bosses" (2mm~5mm high) are provided along the length of the inner side of the frame, and are fixed to the "welding plane" at the connection point with the back panel through continuous or intermittent welding, forming a rigid frame (see...). Figure 1 (Cross view of the connection node on the middle and long sides).

[0042] The silicone strip sealing structure uses trapezoidal or rectangular slots on the inner side of the frame and matching snap-fit ​​protrusions on the outer side of the silicone strip. By embedding into the slots, it achieves elastic compression and sealing of the side of the glass assembly (replacing the traditional structural adhesive sealant for the gap between the frame and the glass). The height of the silicone strip is 0.5mm~1mm greater than the gap between the frame and the glass to ensure no adhesive overflow.

[0043] Traditional components require frame installation on all four sides. This invention replaces the short frame with a short side guard (bent structure) on the back panel, retaining only the two long stainless steel frames, reducing the frame material by 50%. At the same time, welding is used to achieve coordinated stress distribution between the frame and the back panel (traditional aluminum frames and back panels have no structural connection and are only glued together).

[0044] The synergistic enhancement of the welded rigid frame and the corrugated back panel is achieved by welding the stainless steel frame and the back panel to form a "U"-shaped frame (long side frame + back panel body). The corrugated structure extends along the long side, so that when the entire component is subjected to wind pressure, the frame and the back panel share the bending stress, rather than the frame bearing the force alone in the traditional solution, thereby reducing the deflection deformation in the middle of the component by ≥20%.

[0045] The optimized sealing process uses a silicone strip to snap-fit ​​seal between the long side frame and the glass assembly, eliminating the need for structural adhesive application and avoiding adhesive overflow and curing processes. The short side guard is bonded to the short side of the glass with a 0.3mm~1mm thick sealant layer, forming a double sealing structure of "snap-fit ​​+ sealant" to improve waterproof performance.

[0046] The sheet metal processing involves selecting stainless steel sheets (such as 316L stainless steel) with a yield strength ≥205MPa and a tensile strength ≥520MPa, and pressing a corrugated structure (10mm in height and 30mm in spacing) onto the surface of the sheet metal using a roll forming process.

[0047] The long edges on both sides of the board are bent to form a vertically upward connecting part (15mm high), and the surface of the connecting part is polished to a flat welding plane; the short edges on both sides are first bent upward by 20mm (height equal to 5mm glass thickness + 15mm reserved sealing space), and then bent inward by 90° to form a protective edge plane (10mm wide).

[0048] The profile processing involves cutting stainless steel profiles into frames equal in length to the long side of the component. A 3mm high welding boss (rectangular cross-section) is milled along the length of the frame on the inside side, with the boss's position corresponding to the welding plane of the back panel connection. A slot (trapezoidal cross-section, 5mm upper base, 8mm lower base, 6mm depth) is machined on the inside side of the frame near the glass component to hold the silicone strip.

[0049] The lamination bonding process involves applying structural adhesive (1mm thick) to the upper edge area (within 20mm of the edge) and the center area (300mm apart) of the stainless steel corrugated backplate, avoiding the corrugated groove area to prevent adhesive seepage. The battery cell layer (with EVA film) is then laid on the backplate, and the glass assembly is covered. The glass, battery cells, and backplate are then bonded together with the EVA through structural adhesive by heating and curing in a laminator (135℃~150℃, 10min~15min).

[0050] The frame welding and sealing process involves aligning the stainless steel frame with the outer side of the long side of the glass assembly, ensuring the welding protrusions on the frame fit snugly against the welding plane of the back panel connection. Continuous TIG welding (tungsten inert gas welding) is then used for continuous welding (weld length ≥ 95% of the frame length) to create a rigid connection. A silicone strip (trapezoidal cross-section, adapted to the frame slot) is cut and inserted into the slot using snap-fit ​​protrusions. Pressing the silicone strip ensures its inner side fits tightly against the side of the glass assembly, utilizing the elasticity of the silicone to achieve a tight seal.

[0051] The short-side edge protection treatment involves applying a sealant (0.5mm thick) between the edge protection plane of the back panel and the short-side side of the glass assembly. The sealant is made of silicone and cured at room temperature for 24 hours, which enhances the waterproofness and structural stability of the short-side area.

[0052] Surface treatment improves corrosion resistance in coastal high-salt-spray environments by spraying a PVDF coating (30μm thick) on the outer side of the stainless steel frame and the corrugated structure of the back panel, or by passivation treatment.

[0053] In traditional aluminum frame modules, there is no rigid connection between the frame and the back panel. The wind pressure load is mainly borne by the frame and glass, while the back panel only serves an encapsulation function. In this invention, the stainless steel frame and the corrugated back panel are welded to form an integral frame. The corrugated structure increases the moment of inertia of the back panel (increasing the moment of inertia by 40% to 60%), so that when the module is subjected to a wind pressure of 2400Pa, the deflection at the middle is reduced from 8mm in the traditional structure to less than 6.4mm (a reduction of 20%), and the risk of microcracks in the solar cells is reduced by 35% year-on-year.

[0054] Stainless steel (such as 316L) has a salt spray corrosion resistance life of ≥25 years (traditional aluminum frames have a life of about 8~10 years in coastal environments). Combined with a surface PVDF coating (weather resistance rating ≥10000h), the corrosion rate of the component in a salt spray environment can be reduced by more than 70%.

[0055] Silicone strip snap-fit ​​replaces structural adhesive for sealing the frame, eliminating the need for an overflow groove and a 24-hour curing process, reducing the single-module encapsulation time from 48 hours to less than 24 hours; short-side guards replace short frames, reducing the procurement, cutting, and installation of two frames, thus lowering the component material cost by 15% to 20%.

[0056] The long-side silicone strip achieves elastic sealing through physical snap-fit, avoiding sealing failure caused by structural adhesive aging; the thickness of the sealant layer between the short-side edge protector and the glass is controlled at 0.3mm~1mm, forming a composite system of "edge protector structural support + flexible sealant layer", which reduces water vapor permeability by more than 50% compared to traditional four-sided aluminum frame components.

[0057] This structure is particularly suitable for the following harsh environments: coastal areas with high wind pressure (such as typhoon zones, with a design wind pressure ≥2400Pa): the rigid frame and corrugated backsheet enhance wind resistance and reduce component damage; high salt spray corrosion environments (such as islands and coastal power plants): stainless steel materials and anti-corrosion coatings extend component life and reduce operation and maintenance costs; lightweight application scenarios (such as rooftop distributed photovoltaics): reducing the number of frames and lowering component weight (10%~15% lighter than traditional components) while meeting strength requirements.

[0058] Through the above-mentioned technical content and implementation methods, the present invention has achieved a breakthrough in photovoltaic module structure from "independent stress on components" to "synergistic enhancement of materials and structure", solving multiple bottlenecks in strength, corrosion resistance and process of traditional solutions.

[0059] In some embodiments, the inner side of the stainless steel frame is provided with a protruding welding boss along the length direction as the welding part, and the connecting part of the stainless steel corrugated back plate is provided with a welding plane adapted to the welding boss. The welding boss and the welding plane are fixedly connected by continuous welding or intermittent welding, so that the stainless steel frame and the stainless steel corrugated back plate form a rigid connection structure in the long side direction.

[0060] This embodiment relates to the connection structure design of stainless steel frame and stainless steel corrugated back plate. By setting welding bosses on the inner side of the frame and welding planes on the connection part of the back plate, a suitable welding structure is formed. The rigid connection between the two is achieved by continuous or intermittent welding, thereby building a high-strength rigid frame in the long side direction of the component and improving the overall structural strength and wind load resistance.

[0061] The design of the stainless steel frame welding boss includes: Structural parameters: A raised "welding boss" is machined along the length direction (i.e., the long side direction of the component) on the inner side of the stainless steel frame. The boss cross-section is rectangular or trapezoidal (preferably rectangular, height 2~5mm, width 5~10mm), and the boss length is equal to the frame length (error ±0.5mm) to ensure complete alignment with the welding plane of the back panel connection. Machining process: The boss is machined on the inner surface of the frame using CNC milling or stamping. The surface roughness of the boss is ≤Ra1.6μm to ensure welding quality; if it is a rectangular boss, the edges are rounded (R0.5~1mm) to prevent stress concentration.

[0062] The stainless steel corrugated back panel connection treatment includes: Connection structure: The long edges on both sides of the back panel extend vertically upwards to form a "connection," with an extension height of 10~20mm (preferably 15mm, slightly higher than the height of the welding boss on the frame). The surface of the connection is processed by stamping or grinding to create a flat "welding plane," with a flatness error ≤0.2mm / m, ensuring a tight fit with the welding boss. Adaptive design: The width of the welding plane is consistent with the width of the welding boss on the frame (e.g., if the boss width is 8mm, then the welding plane width is 8mm). The two form surface contact during welding, increasing the welding area (contact area ≥95% of the boss surface area).

[0063] The welding and fixing process includes: Welding method selection: Continuous welding: Using TIG (Tungsten Inert Gas Welding) or MIG (Metal Inert Gas Welding), continuous welding is performed along the contact edge between the welding boss and the welding plane. The weld width is 3~5mm, and the penetration depth is 1~2mm (adjusted according to the back plate thickness of 1.0~2.0mm). The weld continuity is ≥95% of the frame length, forming a complete rigid connection interface. Intermittent welding: A weld segment (single weld length 20~30mm) is set every 100~200mm along the long side. The interval area is fixed by positioning welds. This is suitable for weight-sensitive scenarios, reducing the amount of welding while ensuring rigidity (total weld length ≥60% of the frame length).

[0064] Post-welding treatment involves grinding and polishing the weld to remove slag and surface oxide layer. Penetrant testing is performed when necessary to ensure there are no defects such as incomplete welds or cracks. The perpendicularity error between the frame and the back panel after welding is ≤0.5° to ensure the overall flatness of the component.

[0065] By combining the welding boss with the welding plane, a triple connection structure of "boss embedding - plane bonding - weld reinforcement" is formed, which makes the connection strength between the frame and the back plate in the long side direction ≥80MPa (10~15MPa higher than the traditional bonding strength), and the shear displacement resistance is increased by more than 5 times. It can effectively and collaboratively bear wind pressure loads and reduce the bending deformation of the long side of the component.

[0066] In some embodiments, the short edge of the stainless steel corrugated back plate extends upward to a height greater than or equal to the thickness of the glass assembly, and the extended portion is bent inward to form a protective edge plane that fits against the short side of the glass assembly. The width of the protective edge plane covers a predetermined protection area of ​​the short edge of the glass assembly.

[0067] This embodiment optimizes the short-side structure of photovoltaic modules by extending and bending the short-side edge of the stainless steel corrugated backplate upwards to form a protective edge plane that fits against the short-side side of the glass module. The height of the protective edge is greater than or equal to the glass thickness, and the width covers the preset protection area of ​​the short-side edge of the glass, replacing the traditional short frame, simplifying the module structure and improving the short-side sealing and protection.

[0068] The short-side edge protection structure design includes: extension height: the height H of the vertical extension of the short edge of the back panel is greater than or equal to the thickness t of the glass assembly (e.g., if the glass thickness is 5mm, then H = 5~8mm, with a 3mm sealing space reserved), ensuring that the edge protection plane can cover the effective protection area of ​​the short side of the glass after the extension is bent.

[0069] Bending process: The extended part is bent inward at 90° (bending radius R=2~3mm to prevent the sheet from cracking) to form a "protective edge plane". The protective edge plane is parallel to the short side of the glass component, with a gap of ≤0.5mm (controlled by mold precision) to ensure a tight fit.

[0070] Edge protector plane parameters: Width design: The width W of the edge protector plane covers the "pre-defined protection area" of the short edge of the glass assembly, that is, extending 5~10mm (preferably 8mm) inward from the glass edge, ensuring that the edge protector can block the cut edge of the short edge of the glass and prevent moisture and salt from directly corroding the chamfered area of ​​the glass. Surface treatment: The inner side of the edge protector plane (the side that fits against the glass) is frosted (roughness Ra3.2~6.3μm) to enhance the adhesion with the sealant; the outer side remains smooth to facilitate subsequent possible coating spraying.

[0071] Matching with glass components: Installation and positioning: Before bonding the back panel to the glass components, use positioning fixtures to align the short edge of the back panel with the short edge of the glass. The fit error between the edge plane and the side of the glass should be ≤1mm to ensure that the edge completely covers the edge of the short side of the glass.

[0072] Sealing treatment: Apply silicone sealant (0.3~1mm thick) between the edge protector plane and the short side of the glass. The sealant layer fills the gap evenly to form a flexible seal. At the same time, the metal structure of the edge protector provides rigid support for the short side of the glass, replacing the mechanical fixing function of the traditional short frame.

[0073] This design eliminates the two short frames (top and bottom frames) of traditional components, retaining only two long frames, reducing the number of frame components by 50% and material costs by 15%. The "bending and bonding + sealing" design of the edge protection structure and the short glass edge not only provides mechanical protection for the short edge area (increasing impact resistance by 20%), but also blocks the water vapor penetration path through the sealing adhesive layer, improving the reliability of the adhesive seal compared to the traditional short frame.

[0074] In some embodiments, a structural adhesive layer is applied to the edge and / or center area of ​​the upper surface of the stainless steel corrugated back panel, the thickness of the structural adhesive layer being 0.5 mm to 2 mm, and the glass assembly is bonded to the stainless steel corrugated back panel through the structural adhesive layer, the application area of ​​the structural adhesive layer avoiding the corrugated groove area of ​​the stainless steel corrugated back panel.

[0075] This embodiment relates to the optimization of the bonding process between the glass assembly and the stainless steel corrugated backsheet. By applying a structural adhesive layer of a specific thickness to the edge area and / or center area on the upper surface of the backsheet, avoiding the corrugated groove area, the bonding strength is ensured while preventing the adhesive from seeping into the interior of the corrugated structure, thereby improving the reliability of interlayer bonding and the fatigue resistance of the assembly.

[0076] The structural adhesive coating area planning includes: edge area coating: apply a ring-shaped structural adhesive layer with a width of 15-25mm on the upper surface edge of the back panel (20-30mm from the long edge and 15-20mm from the short edge) to form a sealing and bonding strip at the edge of the component, preventing external moisture from seeping in from the edge.

[0077] Interval coating in the central area: In the planar area between the crests of the corrugated structure of the backsheet (avoiding the grooves), rectangular or strip adhesive layers (50mm×50mm in size) are set every 200~300mm. The spacing of the adhesive layers matches the corrugated structure wave pitch to ensure multi-point bonding between the battery cell layer and the backsheet and to distribute the load.

[0078] Adhesive layer thickness and materials include: Thickness control: An automatic coating machine is used to control the structural adhesive layer thickness to 0.5~2mm (preferably 1mm). Uniform coating is achieved by adjusting the coating head pressure and moving speed, with an adhesive layer thickness error of ±0.1mm. Material selection: Two-component silicone structural adhesive or EVA structural adhesive (tensile strength ≥3MPa after curing, elongation at break ≥200%) is selected, which has good weather resistance and metal adhesion, and is especially suitable for stainless steel surfaces.

[0079] The process of avoiding corrugated grooves includes: Groove identification: After the back panel is processed, the location of the corrugated grooves is located using a vision inspection system to generate a coating path, ensuring that the adhesive layer is applied only to the planar area of ​​the corrugated crests (i.e., the non-recessed part of the upper surface of the back panel). Anti-penetration design: If the depth of the corrugated groove is ≥5mm, the edge of the groove is treated with adhesive blocking (such as setting a temporary baffle) before coating to prevent adhesive from flowing and seeping into the groove, affecting the structural rigidity of the back panel (if the groove is filled with adhesive, it may cause the buffering and energy absorption function of the corrugated structure to fail).

[0080] The bonding and curing process includes: Lamination assembly: After applying structural adhesive, the battery cell layer (with EVA film) and glass module are laid sequentially, ensuring the glass edge is aligned with the backsheet edge (error ≤ 1mm). Heating and curing are performed using a vacuum laminator (temperature 135~150℃, time 10~15min), allowing the structural adhesive and EVA film to cure simultaneously, forming a three-layer bonding system of glass-battery-backsheet. After curing, a peel test is conducted. The bond strength between the glass and backsheet is ≥ 5N / mm (along the edge adhesive layer), and the shear strength of the central adhesive layer is ≥ 2MPa, ensuring no risk of interlayer delamination during long-term use of the module.

[0081] In some embodiments, the stainless steel frame and the stainless steel corrugated back plate are made of stainless steel material, wherein the yield strength of the stainless steel material is greater than or equal to 205 MPa and the tensile strength is greater than or equal to 520 MPa.

[0082] This embodiment specifies the mechanical properties of the stainless steel material used for the stainless steel frame and corrugated back panel, requiring a yield strength ≥205MPa and a tensile strength ≥520MPa to meet the strength requirements under high wind pressure conditions. At the same time, the corrosion resistance of stainless steel material is used to improve the overall lifespan of the component and adapt it to highly corrosive environments such as coastal areas.

[0083] Stainless steel is preferred for materials with a yield strength of 205MPa and a tensile strength of 520MPa or a yield strength of 210MPa and a tensile strength of 520MPa. The latter is suitable for high salt spray environments (containing molybdenum, which improves corrosion resistance by more than 3 times). The material should conform to GB / T 3280 or ASTM A240 standards.

[0084] The stainless steel corrugated back panel is made of 1.0~2.0mm thick cold-rolled stainless steel sheet with a surface roughness Ra≤1.6μm. The width of the sheet is customized according to the component size (error ±0.5mm).

[0085] Stainless steel frame: Uses "L" or "U" shaped stainless steel profiles with a wall thickness of 2.0~3.0mm. The cross-sectional dimensions are designed according to the thickness of the components (e.g., when adapting to 5mm glass, the frame height is 30mm and the width is 20mm).

[0086] For each batch of stainless steel sheets / profiles, a material report must be provided to test the yield strength (through tensile testing, gauge length 50mm, tensile rate 5mm / min) and tensile strength (maximum tensile force at break), ensuring that the measured values ​​are ≥205MPa and 520MPa.

[0087] The component-level strength test was conducted by wind pressure test (positive pressure 2400Pa, negative pressure -1500Pa) according to relevant standards. The maximum deflection of the component using the material in this embodiment is ≤1 / 200 of the short side length of the glass (e.g., 1600mm short side, deflection ≤8mm), which is significantly better than the traditional aluminum frame component (deflection ≤1 / 150, i.e. 10.7mm).

[0088] Passivation treatment involves nitric acid-based passivation of the stainless steel surface (immersion in a 20%~30% nitric acid solution at a temperature of 40~50℃ for 15~20 minutes) to form a dense oxide film, thereby enhancing its resistance to chloride ion corrosion.

[0089] The coating process involves spraying a PVDF fluorocarbon coating (dry film thickness 30~50μm) onto the outer side of the frame and the exposed surface of the back panel. The coating adhesion is ≥5B grade (cross-cut test) and the salt spray resistance time is ≥1000h (ASTM B117 standard), which further extends the material life.

[0090] By selecting stainless steel with high yield strength and high tensile strength, the tensile strength of the frame and back plate is increased by 100% compared with traditional aluminum profiles (6063-T5 aluminum, tensile strength 260MPa). Under the same cross-sectional size, the bending stiffness of the stainless steel structure is increased by 60%. At the same time, the corrosion resistance of stainless steel extends the service life of the components in coastal environments from 10 years to more than 25 years, significantly reducing operation and maintenance costs and replacement frequency.

[0091] In some embodiments, the inner side of the stainless steel frame is provided with a slot with a trapezoidal or rectangular cross section, and the outer side of the silicone strip is provided with a snap-fit ​​protrusion adapted to the slot. The silicone strip is embedded in the slot through the snap-fit ​​protrusion, and the inner side of the silicone strip is tightly fitted with the side of the glass assembly to form an elastic compression sealing structure. The height of the silicone strip is greater than the gap between the stainless steel frame and the side of the glass assembly.

[0092] This embodiment relates to a sealing structure design for the stainless steel frame and the side of the glass assembly. A trapezoidal or rectangular groove is provided on the inner side of the frame, paired with a silicone strip on the outer side with adaptive snap-fit ​​protrusions, forming an elastic compression sealing structure. The height of the silicone strip is greater than the gap between the frame and the glass, achieving a seal connection without adhesive overflow through physical snap-fit, replacing traditional structural adhesive sealing processes, simplifying the process and improving sealing reliability.

[0093] The cross-sectional shape and size are determined by processing a slot on the inner side of the frame near the glass component. The cross-section is trapezoidal (top base 5~8mm, bottom base 8~12mm, depth 6~10mm) or rectangular (width 8~10mm, depth 8~10mm). The length of the slot is the same as the frame, and the edges are rounded (R0.5~1mm) to prevent stress concentration.

[0094] The processing technology adopts CNC milling or die stamping. The roughness of the inner wall of the slot is ≤Ra3.2μm to ensure that the silicone strip snap-fit ​​protrusion fits tightly with the slot, and the tolerance is controlled within ±0.2mm.

[0095] The snap-fit ​​protrusion design features a protrusion on the outside of the silicone strip that matches the slot (trapezoidal protrusion with an upper base of 4-7mm, a lower base of 7-11mm, and a height of 5-9mm; or rectangular protrusion with a width of 7-9mm and a height of 7-9mm). The protrusion is the same length as the silicone strip, and its cross-sectional dimensions are 0.5mm smaller than the slot to achieve an interference fit.

[0096] The material selected is silicone rubber with a Shore hardness of 60~70A, tensile strength ≥5MPa, elongation at break ≥300%, weather resistance ≥10000h, and a smooth surface free of impurities, ensuring that it will not age or crack after long-term use.

[0097] Before assembly, measure the gap H between the side of the glass assembly and the inner side of the frame (usually 5~8mm). Select the silicone strip height H' = H + 0.5~1mm to ensure that the inner side of the silicone strip tightly presses against the side of the glass after snapping. (Compression amount 5%~10%).

[0098] The snap-fit ​​process involves embedding a silicone strip along the length of the frame slot, and pressing it with a tool to ensure that the snap-fit ​​protrusion is fully inserted into the slot without warping or falling off; the two ends of the silicone strip extend 10-15mm beyond the frame, and after cutting, they are fixed with silicone glue to prevent water seepage at the ends.

[0099] This structure replaces structural adhesive coating with physical snap-fit, completely eliminating the risk of adhesive overflow and contamination. The elastic deformation of the silicone strip can adapt to the thermal expansion and contraction during long-term use of the module (displacement compensation ±0.3mm). The sealing life is synchronized with the module (≥25 years), which is more than 3 times longer than traditional structural adhesive sealing (life 8~10 years). At the same time, it eliminates the 24-hour curing process and shortens the encapsulation time of a single module.

[0100] In some embodiments, the corrugated structure is a continuous wavy or trapezoidal protrusion, the spacing between adjacent corrugated protrusions is 10 mm to 50 mm, the height of the corrugated protrusions is 5 mm to 15 mm, and the extension direction of the corrugated structure is consistent with the long side direction of the glass assembly.

[0101] This embodiment defines the corrugated structure parameters of the stainless steel corrugated back panel, which adopts continuous wavy or trapezoidal protrusions with a protrusion spacing of 10~50mm and a height of 5~15mm. The extension direction is consistent with the long side of the glass. By increasing the moment of inertia of the back panel section, the bending resistance is improved, the overall rigidity of the component is enhanced, and the deflection deformation under high wind pressure is reduced.

[0102] Cross-sectional shape: Wavy: using a sine curve or circular arc transition, with a height difference of 5~15mm between crests and troughs (preferably 10mm), wavelength (distance between adjacent crests) of 10~50mm (preferably 30mm), and crest arc radius R=3~5mm to avoid stress concentration. The protrusions are isosceles trapezoids, with an upper base of 10~20mm, a lower base of 20~40mm, and a height of 5~15mm (preferably 12mm in height and 80°~90° in base angle), and a distance of 10~50mm (preferably 40mm) between adjacent trapezoidal protrusions.

[0103] The extension direction extends continuously along the long side of the glass component (i.e., the length direction of the component) through the corrugated structure, which is consistent with the direction of the rigid frame formed by welding the stainless steel frame, so that the load is transmitted along the direction of the strongest stiffness.

[0104] Roll forming uses a custom roll forming mold to cold process 1.0~2.0mm stainless steel sheets. It is a single roll forming process, and the mold temperature is controlled at 50~80℃ (to prevent the sheet from hardening and cracking). After forming, the corrugation height error is ±0.5mm and the straightness error is ≤1mm / m.

[0105] Edge treatment involves making flat cuts at both ends of the corrugated structure to ensure a smooth transition area between the connection with the back panel (long side) and the short side guard (short side), thus avoiding stress concentration points.

[0106] Corrugated structures increase bending stiffness by increasing the moment of inertia (I) of the back plate section. For example, the moment of inertia of a planar back plate is I0 = bh. 3 / 12 (b is the width, h is the thickness), the moment of inertia of the corrugated back panel is I = I0 + Ay 2 (A is the cross-sectional area, y is the distance from the centroid to the neutral axis) When the corrugation height is 10mm, the moment of inertia can be increased by 40%~60%, which reduces the mid-span deflection of the component under 2400Pa wind pressure from 10mm of the traditional planar backplate to 6~7mm, and significantly enhances the bending resistance.

[0107] In some embodiments, the stainless steel frame and the stainless steel corrugated back plate are welded to form a rigid frame. The stiffness of the long side of the frame is improved compared with that of traditional aluminum frame components. When the photovoltaic module is subjected to wind pressure load, the stainless steel frame and the stainless steel corrugated back plate work together to bear bending stress.

[0108] This embodiment illustrates the collaborative stress mechanism of the rigid frame formed by welding the stainless steel frame and the corrugated back plate under load. Through the rigid connection between the two, the stiffness of the long side of the module is improved compared with the traditional aluminum frame module. Under wind pressure, the frame and the back plate jointly bear the bending stress, reducing the deflection deformation in the middle of the module and reducing the risk of microcracks in the cells.

[0109] The welding connection characteristics include the formation of a rigid node between the frame welding boss and the back plate connection through continuous welding (weld continuity ≥95%), making the frame and back plate mechanically integrated, and the load transfer path changes from "frame alone bearing force" to "frame + back plate bearing force together".

[0110] The stiffness improvement was quantified through finite element simulation analysis. The stiffness of the long side of the traditional 6063-T5 aluminum frame component is EI2. In this embodiment, the stiffness of the stainless steel frame is EI2=EI1×1.8~2.0 (because the elastic modulus of stainless steel is 200GPa vs aluminum is 70GPa, and the corrugated structure increases the moment of inertia of the back plate). The overall stiffness is improved by 80%~100%.

[0111] Stress distribution optimization: When the component is subjected to positive wind pressure (air pressure towards the glass), the stainless steel frame bears tensile stress, and the crest area of ​​the corrugated back panel bears compressive stress. The two form a force couple balance through the welded joint, reducing the bending moment borne by the frame alone (bending moment is reduced by 30%~40%). Under negative pressure (pressure away from the glass), the frame bears compressive stress, and the corrugated structure of the back panel provides supporting reaction force, suppressing the back panel's concave deformation.

[0112] Deflection control was tested according to standards. For a traditional module (1600mm × 1000mm), the deflection Δ1 = 12mm under 2400Pa wind pressure. In this embodiment, the deflection Δ2 = 8~9mm (Δ2 / Δ1 ≤ 75%). The deformation gradient in the area where the solar cells are located is reduced, and the risk of microcracks is reduced from 15% in the traditional solution to below 5% (verified by EL imaging). Fatigue testing involved 100,000 cycles of wind pressure loading (±2400Pa). No cracks were found at the welded joints, no silicone strip detachment, and no plastic deformation in the corrugated structure, verifying the long-term reliability of the cooperative stress-bearing structure.

[0113] In some embodiments, a sealant layer is provided between the short side guard of the stainless steel corrugated back plate and the short side of the glass assembly. The sealant layer is applied to the contact area between the guard plane and the short side of the glass assembly, and the thickness of the sealant layer is 0.3 mm to 1 mm, replacing the sealing structure of the traditional short frame.

[0114] This embodiment focuses on strengthening the seal between the short-side guard and the glass assembly. A 0.3~1mm thick sealant layer is applied between the guard plane and the short side of the glass to replace the traditional short-side frame sealing structure, thereby enhancing the waterproof performance and structural stability of the short-side area. At the same time, the metal support of the guard improves the impact resistance of the short side.

[0115] The sealant layer design includes: Application area: Sealant is applied only to the contact area between the edge protector plane and the short side of the glass, with a width covering the full width of the edge protector plane (usually 5~10mm) and a length from one end of the short side to the other, forming a continuous sealing band. Thickness control: Precision coating equipment (such as a screw pump + slit die) is used to control the sealant layer thickness to 0.3~1mm (preferably 0.5mm), ensuring a uniform sealant layer without bubbles and neat edges without excess sealant (the edge protector bending structure prevents sealant overflow).

[0116] The sealant materials and processes include: Material selection: two-component silicone sealant (surface drying time ≤30min, hardness after curing 30~40 Shore A, tensile bond strength ≥1.5MPa, bond strength with stainless steel and glass ≥2.0MPa), with low modulus, high displacement capacity (±25% deformation), and adaptability to dimensional fluctuations caused by temperature changes.

[0117] Construction process: ① Clean the edge protector and the short edge of the glass (wipe off oil stains with alcohol); ② Apply masking tape along the inner edge of the edge protector to define the width of the adhesive layer; ③ Apply sealant evenly, controlling the thickness through the nozzle orifice diameter (φ0.8~1.2mm); ④ Attach to the short edge of the glass, apply 5~10N / cm² pressure to fix, and cure at room temperature for 24 hours (humidity ≥50%); ⑤ Remove the masking tape and clean off any excess adhesive from the edges.

[0118] The sealant layer and the short-side protective edge form a composite system of "metal structural support + flexible sealant layer", with a water vapor permeability ≤5g / (m²). 2 *24h) (Traditional short-frame adhesive structure permeability ≥10g / (m 2 *24h), while the stainless steel material of the edge protector provides three times the impact resistance of the traditional aluminum frame (withstanding ≥5J impact energy from a 15mm steel ball), significantly improving the waterproofness and structural safety of the short side area.

[0119] In some embodiments, the outer surface of the stainless steel frame is provided with an anti-corrosion coating, which is an epoxy resin coating or a polyvinylidene fluoride coating, and the thickness of the coating is 20 micrometers to 50 micrometers. The corrugated structure surface of the stainless steel corrugated back plate is simultaneously passivated or coated with an anti-corrosion coating.

[0120] This embodiment focuses on corrosion resistance enhancement in coastal high-salt-fog environments. Anti-corrosion coatings (epoxy resin or PVDF coating, 20~50μm thick) are applied to the outer side of the stainless steel frame and the surface of the corrugated back plate. At the same time, the back plate is passivated to form a multi-layer anti-corrosion system, which extends the service life of the component in harsh environments.

[0121] Surface pretreatment includes: Degreasing and oil removal: Immerse the stainless steel frame and back plate in an alkaline degreasing solution (NaOH concentration 5%~10%) at 50~60℃ for 10~15 minutes to remove surface oil and processing residues, wash with water and dry (moisture content ≤0.1%). Sandblasting roughening: Sandblast the outer side of the frame and the corrugated surface of the back plate with quartz sand (abrasive particle size 80~120 mesh) to increase the roughness to Ra3.2~6.3μm and enhance coating adhesion.

[0122] The anti-corrosion coating process includes: passivation treatment: the surface of the corrugated structure of the back plate is immersed in a 20%~30% nitric acid solution (temperature 40~50℃) for 15~20 minutes to form a Cr2O3 passivation film with a thickness of 1~3μm, which improves the resistance to chloride ion corrosion (the corrosion rate is reduced by 60% in the salt spray test).

[0123] Coating application: ① Epoxy resin coating: High-pressure airless spraying, coating thickness 20~30μm, curing conditions 120℃×30min, forming a dense epoxy protective layer, salt spray resistance time ≥500h. ② PVDF coating: Preferably 70% polyvinylidene fluoride coating, two coats of primer (10~15μm) and topcoat (20~30μm), curing temperature 230~240℃×20min, total thickness 30~50μm, salt spray resistance time ≥1000h, weather resistance ≥20 years.

[0124] Coating quality control includes: Thickness inspection: using a magnetic thickness gauge, one point is inspected every 200mm, with the coating thickness deviation of the border ≤ ±5μm and the coating thickness deviation of the back panel ≤ ±8μm. Adhesion test: cross-cut test (1mm spacing), coating peeling area ≤ 5% (5B grade is optimal, this process can achieve 4B~5B grade).

[0125] In some embodiments, this embodiment proposes a method for optimizing the structural parameters of stainless steel corrugated backsheets using a genetic algorithm. Targeting high wind pressure scenarios for photovoltaic modules, the method uses the corrugated protrusion height, spacing, and cross-sectional angle as optimization variables, and takes maximizing the bending stiffness and minimizing the weight of the backsheet as dual objectives. The method generates the optimal combination of structural parameters through an intelligent algorithm, breaking through the limitations of traditional empirical design and achieving a balance between structural performance and material cost.

[0126] The variable parameters include: corrugated protrusion height h (5~15mm, step size 1mm); adjacent protrusion spacing d (10~50mm, step size 5mm); trapezoidal protrusion base angle θ (70°~90°, step size 5°, and for wavy protrusion, the arc radius R 3~8mm).

[0127] Objective function: Bending stiffness target f1 = max(I / m), where I is the moment of inertia of the section and m is the mass of the back plate.

[0128] Constraints: Component long side deflection δ≤L / 200 (L is component length), and processing feasibility (protrusion height ≤ sheet thickness × 8 times).

[0129] The implementation process of the genetic algorithm includes: Population initialization: Randomly generate 100 sets of initial parameter combinations (chromosomes are encoded as [h,d,θ] or [h,d,R]), with an encoding accuracy of 0.1mm / 1°.

[0130] Fitness calculation: ① Establish a parametric finite element model based on ANSYS, input each set of parameters to calculate I and m; ② Use the linear weighting method to integrate the two objectives: fitness = 0.6 (I / Imax) + 0.4 (mmin / m), where Imax and mmin are the initial population extreme values.

[0131] Evolutionary operations: Selection: A roulette wheel selection process retains the top 50% of high-quality individuals; Crossover: Two-point crossover (probability 0.8) generates new parameter combinations; Mutation: Random perturbation of a single variable (probability 0.1, perturbation range ±10%). Termination condition: Fitness value fluctuation ≤1% for 10 consecutive generations, outputting optimal parameters. Hardware configuration: A GPU cluster (NVIDIA A100×4) is built to accelerate finite element calculations; single-set simulation time ≤30s.

[0132] Machining parameter mapping: The optimized h, d, θ are input into the rolling die CAD system to automatically generate the machining path (accuracy ±0.2mm). Performance comparison: Compared with traditional experience-based designs, the backplate bending stiffness is increased by 22%, the weight is reduced by 15%, the deflection under 2400Pa wind pressure is reduced from 7.2mm to 5.8mm, and the material cost is reduced by 8%.

[0133] In some embodiments, this embodiment develops a real-time detection system for welding defects in stainless steel frames based on the YOLOv8 deep learning model. Targeting defects such as incomplete welds, cracks, and porosity that may occur during TIG / MIG welding, the system collects infrared and visible light images of the weld seam, constructs a multimodal dataset to train the detection model, and achieves automated judgment of welding quality, replacing the inefficiency and subjectivity of manual visual inspection.

[0134] Sensor configuration: A visible light camera (12 megapixels, 60fps) is aimed at the weld area with a resolution of 1920×1080; an infrared thermal imager (accuracy ±2℃, 320×240 pixels) simultaneously acquires temperature distribution images within 30 seconds after welding.

[0135] The dataset was constructed by manually annotating 3,000 defect samples (containing 6 types of defects: incomplete weld, crack, porosity, undercut, weld bead, and lack of fusion), and then expanding it to 15,000 samples using Mosaic data augmentation technology; the image size was normalized to 640×640, and the annotation format followed the COCO dataset standard.

[0136] Model training and optimization include: Network architecture: Backbone network: CSPDarknet53, with embedded Focus structure to improve small target detection capability; Neck: PAFPN feature pyramid to enhance multi-scale defect feature fusion; Head: Decoupled head design, with independent optimization of classification and regression branches.

[0137] Training parameters: Loss function: CIoU Loss (bounding box regression) + BCE Loss (classification); Optimizer: AdamW (learning rate 1e-4, weight decay 0.0005), training epochs 50, batch size 32.

[0138] Real-time inference: Deployed to edge computing devices (NVIDIA Jetson AGX Orin), with an inference speed of ≥30fps, meeting the real-time inspection requirements of the production line; the confidence threshold is set to 0.7, with a defect false negative rate of ≤0.5% and a false positive rate of ≤1%.

[0139] The inspection process and feedback include: online inspection: after each 100mm weld is completed, dual-modal image acquisition is triggered, and the model outputs the defect type and location simultaneously; closed-loop control: if the same type of defect (such as cold weld) is detected three times in a row, the welding parameters are automatically adjusted (current +5A, speed -10mm / s), and the component is marked to enter the manual re-inspection process.

[0140] In some embodiments, this embodiment constructs a microcrack prediction model based on a long short-term memory network (LSTM). By collecting multi-dimensional time-series signals such as strain data, ambient temperature, and wind pressure load during component operation, the model is trained to learn the characteristic patterns before microcracks occur, thereby achieving early warning of microcracks in solar cells, solving the problem of lag in traditional EL imaging detection, and reducing operation and maintenance costs.

[0141] Sensor selection includes: strain gauges (accuracy ±0.01με) are attached to the gaps between the cells in the middle of the module to monitor mechanical deformation; temperature and humidity sensors (accuracy ±0.5℃ / ±2%RH) and wind pressure sensors (accuracy ±10Pa) are installed on the module bracket. Data acquisition frequency: 10Hz real-time acquisition, generating a set of feature vectors every 10 minutes (including 12 features such as average strain, strain fluctuation amplitude, temperature gradient, and cumulative wind pressure cycle count).

[0142] Network structure: Input layer: 12-dimensional features, time step takes the past 24 hours of data (144 time steps); Hidden layer: 2 layers of LSTM units (128 neurons each), embedded with Dropout layer (0.8 retention rate) to prevent overfitting; Output layer: binary classification (0=normal, 1=possibly hilarious split within the next 72 hours), activation function Sigmoid.

[0143] The training data consisted of 3,000 sets of historical data, including 800 sets of positive samples (data from 72 hours before the occurrence of the hidden crack) and 2,200 sets of negative samples. The data were normalized to Z-score standardization and divided into an 8:2 training set and a validation set.

[0144] The loss function is binary cross-entropy, and the optimizer is RMSprop (learning rate 1e-3). Training terminates if the validation set loss does not decrease for 10 consecutive rounds, and the final model's AUC-ROC ≥ 0.92. Real-time data streams are input into the model, and an early warning is triggered when the predicted probability is ≥ 0.8. After the warning, a drone equipped with an EL detector is automatically dispatched to scan the component. Once a hidden crack is confirmed, a work order is generated, and a robot is dispatched to perform local repairs (such as applying conductive adhesive). The average response time is ≤ 2 hours, detecting potential hazards 3-5 days earlier than manual inspection.

[0145] In some embodiments, this embodiment proposes a real-time optimization method for photovoltaic module installation angle based on deep reinforcement learning (DRL). For tracking support systems, historical sunshine data, weather forecasts, and module temperature are used as state inputs. The pitch and azimuth angles are dynamically adjusted through the Actor-Critic algorithm to maximize power generation efficiency and solve the problem of insufficient adaptability of traditional PID control strategies to complex weather conditions.

[0146] Status St: Real-time light intensity (0~2000W / m²) 2 ), solar altitude angle / azimuth angle (obtained via GPS+IMU); component surface temperature (infrared thermometry), cloud coverage (obtained via meteorological API), and historical 1-hour power generation.

[0147] Action At: Pitch angle adjustment range [-20°, +60°], step size 1°; Azimuth angle adjustment range [0°, 180°], step size 2°; The action space is discretized into 181×91 combinations, and is generated by a Gaussian policy network when using continuous action output.

[0148] Reinforcement learning architectures include: Network structures: Actor network: 3 fully connected layers (10-dimensional input layer, 256 / 128 neurons in the hidden layer, and 2-dimensional action value in the output layer); Critic network: Input state + action, output Q-value, with an architecture symmetrical to Actor and sharing the weights of the first two layers.

[0149] Reward function Rt: Rt=P t-α*|Δθ|-β•Eact; where Pt is the real-time power generation, Δθ is the angle adjustment range, Eact is the actuator energy consumption, α=0.1, β=0.5 are penalty coefficients.

[0150] Training and deployment include: Offline training: A simulation environment is built using one year of historical meteorological data. The Proximal Policy Optimization (PPO) algorithm is used for training. Each episode lasts 24 hours, and a total of 10,000 episodes are trained. At convergence, the power generation efficiency is improved by 12% compared to a fixed tilt angle. Online optimization: Deployed to an edge controller (computing power ≥ 1 TOPS), the optimal angle is generated every 10 minutes based on the latest state, with an adjustment accuracy of ±0.5° and a response latency ≤ 2s, adapting to rapid changes in illumination under cloudy weather (e.g., prioritizing the tracking of diffuse light direction when clouds obstruct the view).

[0151] In some embodiments, this embodiment designs a fuzzy logic control system to collect parameters such as ambient temperature, adhesive viscosity, and coating speed in real time during the short-side sealant coating process of photovoltaic modules. The system automatically adjusts the coating pressure and nozzle height through a fuzzy rule library to solve the problem of uneven adhesive layer thickness in temperature-changing environments when coating with traditional fixed parameters, ensuring that the sealant layer thickness is stable within the range of 0.3~1mm.

[0152] The fuzzy controller design includes: input variables: temperature T (10~40℃, fuzzy set: {low temperature, normal temperature, high temperature}); adhesive viscosity μ (measured in real time by a viscometer, fuzzy set: {low viscosity, medium viscosity, high viscosity}); coating speed v (50~200mm / s, fuzzy set: {slow speed, medium speed, fast speed}).

[0153] Output variables: coating pressure P (0.2~0.8MPa); nozzle height H (0~5mm, distance from the edge protector plane).

[0154] The fuzzy rules are established by creating 9×9×9=729 rules (example: if T is high temperature, μ is low viscosity and v is fast, then P is medium pressure and H is low position). The rules are optimized through expert experience and orthogonal experiments.

[0155] Sensors and actuators: Temperature sensor (Pt100, accuracy ±0.5℃) and viscometer (rotary, accuracy ±2%FS) are installed in the glue tank; servo motor drives the nozzle height (accuracy ±0.1mm), and pressure sensor provides feedback on the coating pressure (accuracy ±0.01MPa).

[0156] The control process includes: ① Real-time acquisition and fuzzification of T, μ, and v (the membership function adopts a triangular distribution); ② Calculation of the fuzzy output value using the Mamdani inference method, followed by defuzzification using the centroid method; ③ Outputting P and H to the PLC, updating the control parameters every 50ms.

[0157] In an environmental chamber test at -10℃ to 50℃, the thickness fluctuation of the adhesive layer was ±0.3mm when using traditional fixed-parameter coating, while the fluctuation of this system was ≤±0.08mm. Especially in high-temperature and low-viscosity scenarios (such as a 30% decrease in viscosity at 40℃), the thickness stability was improved by 4 times. The standard deviation of the bond strength between the sealant and the glass / edge protector was reduced from 0.4MPa to 0.1MPa, significantly reducing the risk of water seepage due to adhesive layer defects.

[0158] In existing technologies, the application of stainless steel in photovoltaic modules is limited to localized corrosion-resistant components (such as screws and connectors), and has never involved a structural design that welds the stainless steel frame to the corrugated backsheet as a single unit. Traditional corrugated backsheets serve only as encapsulation materials, without providing structural reinforcement, and there is no technological concept of using short-side bending of the backsheet to form a protective edge to replace the short frame. Furthermore, the solution of using silicone strips to replace structural adhesive sealing solves the problems of traditional adhesive overflow and long curing times, and this sealing structure is designed in conjunction with the welded frame.

[0159] The core innovation of this invention lies in the dual breakthroughs in material selection and structural design: At the material level, it abandons traditional aluminum frames and aluminum reinforcing ribs, using high-strength stainless steel as both the frame and back panel material. Leveraging the excellent strength and corrosion resistance of stainless steel, it fundamentally improves component performance. At the structural level, through the integrated welding design of the stainless steel frame and corrugated back panel, a rigid frame is formed. The corrugated structure enhances the load-bearing capacity of the back panel, short-side edge protection simplifies the number of frames, and silicone strip sealing optimizes the production process. These technical features work together to achieve multiple technical effects of "strength enhancement, structural simplification, and process optimization," rather than simply replacing materials or adding components.

[0160] It should be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of the application. It should be understood that when an element or layer is referred to as “on,” “adjacent to,” “connected to,” or “coupled to” other elements or layers, it may be directly on, adjacent to, connected to, or coupled to other elements or layers, or there may be intervening elements or layers. Conversely, when an element is referred to as “directly on,” “directly adjacent to,” “directly connected to,” or “directly coupled to” other elements or layers, there are no intervening elements or layers. It should be understood that although the terms first, second, third, etc., may be used to describe various elements, components, areas, layers, and / or portions, these elements, components, areas, layers, and / or portions should not be limited by these terms. These terms are merely used to distinguish one element, component, area, layer, or portion from another element, component, area, layer, or portion. Therefore, without departing from the teachings of this application, the first element, component, area, layer, or portion discussed below may be referred to as a second element, component, area, layer, or portion.

[0161] Spatial relation terms such as “below,” “under,” “below,” “under,” “above,” “above,” etc., are used herein for convenience of description to describe the relationship between one element or feature shown in the figure and other elements or features. It should be understood that, in addition to the orientation shown in the figure, spatial relation terms are intended to also include different orientations of the device in use and operation. For example, if the device in the figure is flipped, then the element or feature described as “below,” “under,” or “below” other elements or features will be oriented “above” other elements or features. Therefore, the exemplary terms “below” and “under” can include both above and below orientations. The device may be otherwise oriented (rotated 90 degrees or otherwise) and the spatial descriptive terms used herein will be interpreted accordingly.

[0162] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of this application. When used herein, the singular forms “a,” “an,” and “the” are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising” and / or “including,” when used in this specification, identify the presence of the stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups. When used herein, the term “and / or” includes any and all combinations of the associated listed items.

[0163] It should also be understood that the term “and / or” as used in this application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0164] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and these modifications or substitutions should all be covered within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A photovoltaic module product structure with a high-strength stainless steel frame and backsheet, characterized in that, It includes a glass assembly, a battery cell layer disposed below the glass assembly, a stainless steel corrugated back plate disposed below the battery cell layer, and stainless steel frames disposed on the outer sides of the long sides of the glass assembly respectively. The long edges of the two sides of the stainless steel corrugated back panel extend upward to form a connecting part. The inner side of the stainless steel frame has a welding part that is welded to the connecting part, thus welding the stainless steel frame and the connecting part of the stainless steel corrugated back panel together. The short edges of the two sides of the stainless steel corrugated back panel extend upward and bend inward to form short edge guards, which are located on the outer sides of the short edges of the glass assembly. The glass assembly and the stainless steel corrugated back panel are bonded together with structural adhesive. A silicone strip is provided between the stainless steel frame and the side of the glass assembly, and the silicone strip is snapped between the stainless steel frame and the glass assembly to compress and seal the glass assembly. The stainless steel corrugated back plate is provided with a corrugated structure, which extends along the long side of the glass assembly; the stainless steel frame is welded to the stainless steel corrugated back plate to form an integral structure.

2. The photovoltaic module product structure according to claim 1, characterized in that, The stainless steel frame has a raised welding boss along its length as the welding part. The connecting part of the stainless steel corrugated back plate has a welding plane that matches the welding boss. The welding boss and the welding plane are fixedly connected by continuous welding or intermittent welding, so that the stainless steel frame and the stainless steel corrugated back plate form a rigid connection structure in the long side direction.

3. The photovoltaic module product structure according to claim 1, characterized in that, The short edge of the stainless steel corrugated back plate extends upward to a height greater than or equal to the thickness of the glass assembly. The extended portion is bent inward to form a protective edge plane that fits against the short side of the glass assembly. The width of the protective edge plane covers the preset protection area of ​​the short edge of the glass assembly.

4. The photovoltaic module product structure according to claim 3, characterized in that, A sealant layer is provided between the short side guard of the stainless steel corrugated back plate and the short side of the glass assembly. The sealant layer is applied to the contact area between the guard plane and the short side of the glass assembly, and the thickness of the sealant layer is 0.3 mm to 1 mm.

5. The photovoltaic module product structure according to claim 1, characterized in that, A structural adhesive layer with a thickness of 0.5 mm to 2 mm is applied to the upper surface edge area and / or central area of ​​the stainless steel corrugated back panel. The glass assembly is bonded to the stainless steel corrugated back panel through the structural adhesive layer, and the coating area of ​​the structural adhesive layer avoids the corrugated groove area of ​​the stainless steel corrugated back panel.

6. The photovoltaic module product structure according to claim 1, characterized in that, The stainless steel frame and stainless steel corrugated back panel are made of stainless steel material, and the yield strength of the stainless steel material is greater than or equal to 205 MPa and the tensile strength is greater than or equal to 520 MPa.

7. The photovoltaic module product structure according to claim 1, characterized in that, The inner side of the stainless steel frame is provided with a slot with a trapezoidal or rectangular cross section, and the outer side of the silicone strip is provided with a snap-fit ​​protrusion adapted to the slot. The silicone strip is embedded in the slot through the snap-fit ​​protrusion, and the inner side of the silicone strip is tightly fitted with the side of the glass assembly to form an elastic compression sealing structure. The height of the silicone strip is greater than the gap between the stainless steel frame and the side of the glass assembly.

8. The photovoltaic module product structure according to claim 1, characterized in that, The corrugated structure consists of continuous wavy or trapezoidal protrusions, with a spacing of 10 mm to 50 mm between adjacent corrugated protrusions and a height of 5 mm to 15 mm. The extension direction of the corrugated structure is consistent with the long side direction of the glass assembly.

9. The photovoltaic module product structure according to claim 1, characterized in that, The stainless steel frame and the stainless steel corrugated back plate are welded to form a rigid frame. The stiffness of the long side of the frame is improved compared with the traditional aluminum frame assembly. When the photovoltaic module is subjected to wind pressure load, the stainless steel frame and the stainless steel corrugated back plate work together to bear the bending stress.

10. The photovoltaic module product structure according to claim 1, characterized in that, The outer surface of the stainless steel frame is provided with an anti-corrosion coating, which is an epoxy resin coating or a polyvinylidene fluoride coating, and the thickness of the coating is 20 micrometers to 50 micrometers. The corrugated structure surface of the stainless steel corrugated back plate is simultaneously passivated or sprayed with an anti-corrosion coating.

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