Junction box and photovoltaic system
By installing the substrate and box on the back plate of the photovoltaic module and a buffer film is arranged therebetween, combining the polishing of threading holes and the protection of the second buffer film, the problem that conventional photovoltaic modules cannot withstand hail above 50mm is solved, and the impact resistance and application range of the photovoltaic system are significantly improved.
Patent Information
- Application Number
- CN202421347566.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-13
- Publication Date
- 2025-03-21
- Estimated Expiration
- 2034-06-13
AI Technical Summary
Conventional photovoltaic modules cannot withstand hail impacts of more than 50mm, resulting in limited applications in special areas.
A junction box and photovoltaic system are designed. By installing the substrate and the box on the back plate of the photovoltaic module and arranging a buffer film between the substrate and the back plate, the contact area and buffering capacity are significantly improved. Meanwhile, the hole walls of the threading holes are polished to ensure smooth and no burrs, and a second buffering film is arranged on the back plate to further protect the threading holes.
The impact resistance of the photovoltaic system is improved, so that it can remain stable when affected by 55mm hail impact, meeting the application needs in hail environments above 50mm.
Smart Images
Figure CN222655144U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of photovoltaic technology, and in particular to a junction box and a photovoltaic system. Background Art
[0002] When carrying out activities in extreme and complex climate environments, energy supply is one of the difficulties that must be overcome. As traditional energy sources are becoming increasingly depleted, new energy has become a new development trend, among which the use of wind and solar power generation to obtain energy has also become the first choice. For the construction of photovoltaic power generation projects in most regions, there is no need to consider the impact of extreme climate on photovoltaic components. However, with the rapid development of new energy around the world and the increasing saturation of photovoltaic power generation projects in ordinary environmental areas, coupled with the rich new energy resources of extreme environments themselves and their demand for new energy development, photovoltaic power generation will inevitably have a wide range of application occasions.
[0003] At present, conventional photovoltaic modules cannot cope with extreme climates in special regions. For example, conventional photovoltaic modules can only withstand 35-40mm hail, but in special regions, hail of more than 50mm may occur, and conventional photovoltaic modules cannot withstand such high levels of hail. Utility Model Content
[0004] The purpose of the present application is to provide a junction box and a photovoltaic system to solve the technical problem that conventional photovoltaic modules in the prior art can only withstand 35-40 mm hail, but hail of more than 50 mm may occur in special areas, and conventional modules cannot withstand such high-grade hail.
[0005] To achieve the above purpose, a technical solution adopted in this application is:
[0006] Provided is a junction box for installation on a photovoltaic module with threading holes arranged on the surface, the junction box comprising a substrate and a box body arranged on the surface of the substrate, wherein the orthographic projection of the box body on the substrate only covers a partial area of the substrate;
[0007] The substrate is used to fit the photovoltaic component so that the orthographic projections of the substrate and the box body on the surface of the photovoltaic component cover the threading holes.
[0008] In one or more embodiments, in a first direction, the extension length of the substrate is greater than or equal to the extension length of the box body; in a second direction, the extension length of the substrate is greater than the extension length of the box body;
[0009] The first direction and the second direction are vertically distributed.
[0010] In one or more embodiments, an extension length of the box body in the first direction is greater than an extension length in the second direction.
[0011] In one or more embodiments, the outer periphery of the substrate is circular, and the box body extends radially from an outer edge on one side of the substrate surface to an outer edge on the other side.
[0012] To achieve the above purpose, another technical solution adopted by this application is:
[0013] A photovoltaic system is provided, comprising:
[0014] A photovoltaic module comprises a cover plate, a battery and a back plate which are stacked in sequence, wherein the back plate is provided with threading holes;
[0015] The junction box described in any of the above embodiments is arranged on the surface of the back plate, and the substrate is arranged in contact with the back plate so that the orthographic projection of the substrate and the box body on the surface of the back plate covers the threading hole;
[0016] The first buffer film is arranged between the back plate and the substrate.
[0017] In one or more embodiments, the photovoltaic system further comprises:
[0018] A first packaging film is arranged between the cover plate and the battery;
[0019] The second packaging film is arranged between the battery and the back plate.
[0020] In one or more embodiments, the photovoltaic system further includes a second buffer film, which is arranged between the second packaging film and the back panel, the second buffer film covers the threading hole, and the second buffer film only covers a partial area of the second packaging film.
[0021] In one or more embodiments, the back panel is provided with a plurality of threading holes spaced apart along the width direction, the second buffer film is extended along the width direction of the back panel to cover the plurality of threading holes, and the extension length of the second buffer film in the length direction of the back panel is one quarter to one half of the length of the back panel.
[0022] In one or more embodiments, the hole wall of the threading hole is a smooth surface.
[0023] In one or more embodiments, the second buffer film is symmetrically arranged relative to the center line of the threading hole.
[0024] In one or more embodiments, the cover plate and the back plate are glass plates, and the thickness of the cover plate and the back plate is greater than or equal to 2.5 mm.
[0025] Different from the prior art, the beneficial effects of this application are:
[0026] The junction box of the present application includes a substrate and a box body, the box body only covers a part of the substrate area, when applied to a photovoltaic module, the substrate and the box body both cover the threading hole, a first buffer film is arranged between the substrate and the back plate, thereby significantly increasing the contact area between the junction box and the back plate of the photovoltaic module, and correspondingly increasing the area of the first buffer film, the first buffer film can play a role in protecting the threading hole, so that when the photovoltaic system is impacted, the first buffer film can form a buffer, absorb part of the impact energy, and improve the impact resistance of the photovoltaic system;
[0027] The threading holes of the photovoltaic system of this application are polished to ensure that the hole walls are smooth and burr-free, which can further improve the overall strength and impact resistance of the photovoltaic system;
[0028] The photovoltaic system of the present application includes a second buffer film to further protect the threading holes and enhance the structural strength and impact resistance of the photovoltaic system;
[0029] The photovoltaic system of the present application can pass the 55 mm hail test and can be applied to special areas where hail of more than 50 mm may occur, thereby increasing the application scope of the photovoltaic system. BRIEF DESCRIPTION OF THE DRAWINGS
[0030] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings required for use in the embodiments or the prior art description are briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present application, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.
[0031] Figure 1 It is a structural schematic diagram of an implementation method of a photovoltaic system of the present application;
[0032] Figure 2 yes Figure 1 Schematic diagram of the cross-sectional structure of the AA surface;
[0033] Figure 3 yes Figure 2 A partial enlarged schematic diagram of B in the middle;
[0034] Figure 4 It is a structural schematic diagram of an implementation method of a junction box of the present application;
[0035] Figure 5 It is a structural schematic diagram of an implementation method of a backplane of the present application.
[0036] Reference numerals:
[0037] Cover plate 100;
[0038] Battery 200; Battery area 201;
[0039] Back plate 300; threading hole 301;
[0040] Junction box 400; substrate 401; box body 402;
[0041] A first buffer film 500;
[0042] A first packaging film 600;
[0043] A second packaging film 700;
[0044] The second buffer film 800 . DETAILED DESCRIPTION
[0045] In order to enable those skilled in the art to better understand the technical solutions in the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work should fall within the scope of protection of this application.
[0046] At present, conventional photovoltaic systems cannot withstand hail larger than 50 mm in certain areas, which limits the application of photovoltaic systems in the above-mentioned areas and affects the development of global new energy.
[0047] In order to solve the above problems, the applicant has developed a new photovoltaic system, which effectively improves the buffering capacity of the photovoltaic system by making simple structural modifications to the conventional photovoltaic system. The photovoltaic system can absorb part of the impact energy when hit by hail, so that the photovoltaic system has the ability to withstand the impact of hail larger than 50mm.
[0048] Specifically, see Figures 1 to 3 , Figure 1 is a schematic diagram of the structure of an embodiment of the photovoltaic system of the present application, Figure 2 yes Figure 1 Schematic diagram of the cross-sectional structure of the AA surface in the middle. Figure 3 yes Figure 2 A partial enlarged schematic diagram of B in the figure.
[0049] like Figure 1 and Figure 2 As shown, the photovoltaic system includes a cover plate 100, a battery 200 and a back plate 300 which are stacked in sequence.
[0050] The battery 200 may include one or more battery areas 201 , each of which may be composed of one or more battery strings (not shown in the figure), and each battery string may be composed of a plurality of battery cells connected in series via welding ribbons.
[0051] The cover plate 100 is used to protect the battery 200 and prevent the battery 200 from being polluted by the external environment; the back plate 300 is used to carry the battery 200.
[0052] In one embodiment, the cover plate 100 and the back plate 300 may be glass plates. In order to improve the structural strength of the entire photovoltaic module and improve the impact resistance, the thickness of the cover plate 100 and the back plate 300 may be greater than or equal to 2.5 mm.
[0053] Exemplarily, the cover plate 100 and the back plate 300 may both be glass plates with a thickness of 2.5 mm.
[0054] In order to lead out the busbars of the battery 200, a threading hole 301 is arranged on the back plate 300. A junction box 400 is arranged on the side of the back plate 300 away from the battery 200, and the busbars of the battery 200 can be connected to the junction box 400 after being led out through the threading hole 301.
[0055] Specifically, Figure 2 and Figure 3 As shown, in this embodiment, the junction box 400 includes a substrate 401 and a box body 402. The substrate 401 is bonded to the back plate 300, and a first buffer film 500 is arranged between the substrate 401 and the back plate 300; the box body 402 is arranged on the side of the substrate 401 away from the back plate 300.
[0056] The orthographic projections of the substrate 401 and the box body 402 on the back plate 300 cover the threading hole 301, while the orthographic projection of the box body 402 on the substrate 401 only covers a partial area of the substrate 401. In addition, in order to introduce the busbar into the box body 402, the substrate 401 and the box body 402 may be provided with openings (not shown) corresponding to the threading hole 301.
[0057] It should be noted that in conventional photovoltaic systems, the junction box 400 is an integral square structure, which is directly arranged on the back plate 300 to cover the threading hole 301, so the contact area between the junction box 400 and the photovoltaic module is limited. The applicant has found through research that the threading hole 301 of the back plate 300 is the weakest link of the photovoltaic module, which is often the first to be damaged when impacted.
[0058] Therefore, in this embodiment, the junction box 400 includes a substrate 401 having an area larger than that of the box body 402. The junction box 400 is arranged on the surface of the back panel 300 through the substrate 401, thereby significantly increasing the contact area between the junction box 400 and the back panel 300, and correspondingly increasing the area of the first buffer film 500. The first buffer film 500 can protect the threading hole 301, so that when the photovoltaic module is impacted, the first buffer film 500 can form a buffer, absorb part of the impact energy, and improve the impact resistance of the photovoltaic module.
[0059] In order to make full use of the space on the surface of the substrate 401 for arranging the box body 402, in this embodiment, in one direction, the extension length of the substrate 401 can be equal to the extension length of the box body 402, and in another perpendicular direction, the extension length of the substrate 401 can be greater than the extension length of the box body 402.
[0060] Of course, in other embodiments, in any direction, the extension length of the substrate 401 may also be greater than the box body 402, as long as the area of the substrate 401 is greater than the box body 402, and the effect of this embodiment can be achieved.
[0061] Specifically, see Figure 4 , Figure 4 Schematic diagram of the structure of a junction box of the present application. Figure 4 As shown, the base plate 401 of the junction box 400 is a circular structure. Compared with the traditional square structure junction box 400, the circular base plate 401 can further increase the contact area between the junction box 400 and the back plate 300, and the circular structure also ensures the force stability.
[0062] like Figure 4 As shown, in this embodiment, the box body 402 is a square structure, and the box body 402 extends from the outer edge of one side of the substrate 401 to the outer edge of the other side along the radial direction of the substrate 401. Based on this structure, the space on the substrate 401 for arranging the box body 402 can be fully utilized, while ensuring the overall force stability.
[0063] For further information, see Figure 2 and Figure 5 , Figure 5 Schematic diagram of the structure of a backplane of the present application. Figure 2 and Figure 5 As shown, in this embodiment, three circular wire holes 301 evenly spaced apart may be arranged on the back plate 300. The three wire holes 301 may be arranged at the midline position in the length direction of the back plate 300. Each wire hole 301 may correspond to a junction box 400, and the corresponding wire holes 301 and the substrate 401 may be concentrically arranged to facilitate the introduction of the bus bar into the box body 402.
[0064] It is worth noting that since jagged edges and burrs often occur when drilling holes in glass, which will affect the overall strength of the structure, the threading holes 301 of the back panel 300 in this embodiment are polished after drilling to ensure that the hole walls of the threading holes 301 are smooth and free of burrs, further improving the impact resistance of the photovoltaic module.
[0065] The following is a detailed description of the fixing method of the cover plate 100 and the back plate 300 in the present application. Figure 2 As shown, a first packaging film 600 is arranged between the cover plate 100 and the battery 200 , and a second packaging film 700 is arranged between the battery 200 and the back plate 300 .
[0066] In order to further protect the threading hole 301 and improve the overall structural strength, a second buffer film 800 is arranged between the second packaging film 700 and the back plate 300. The second buffer film 800 covers the threading hole 301 and only covers a part of the second packaging film 700.
[0067] That is, the second buffer film 800 only covers the threading hole 301 and is not fully spread between the second packaging film 700 and the back plate 300. Its function is to further protect the threading hole 301 and improve the structural strength.
[0068] Specifically, in this embodiment, the three threading holes 301 can be arranged at the midline position in the length direction of the back panel 300, and the second buffer film 800 can be extended along the width direction of the back panel 300 to cover the three threading holes 301. The extension length of the second buffer film 800 in the length direction of the back panel 300 can be one quarter to one half of the length of the back panel 300, thereby protecting the threading holes 301 on the one hand and not affecting the contact between the second packaging film 700 and the back panel 300 on the other hand.
[0069] Illustratively, in one embodiment, the extension length of the second buffer film 800 in the length direction of the back plate 300 may be one third of the length of the back plate 300 .
[0070] Furthermore, the second buffer film 800 can be symmetrically arranged with respect to the center lines of the three threading holes 301, so as to further improve the structural strength.
[0071] Of course, in other embodiments, the position of the threading hole 301 and the arrangement position of the second buffer film 800 can be adjusted based on actual working conditions to ensure that the second buffer film 800 covers the threading hole 301, and the effect of this embodiment can be achieved.
[0072] The effects of the technical solution of the present application are further elaborated in detail below in conjunction with specific embodiments.
[0073] Embodiment 1:
[0074] A photovoltaic system comprises a 2.5 mm thick glass panel, a first packaging film, a battery, a second packaging film, a first buffer film and a 2.5 mm thick glass back plate which are stacked in sequence. A circular threading hole is opened in the center of the glass back plate. The threading hole is polished to ensure that the hole wall is smooth and free of burrs. The first buffer film covers the threading hole, and the extension length of the first buffer film in the length direction of the back plate is one third of the length of the back plate.
[0075] A junction box is provided on the back of the glass back panel, which includes a circular substrate and a square box body. The substrate is fixed to the surface of the back panel through a second buffer film. The substrate covers the threading hole and is concentrically arranged with the threading hole. The box body is arranged on the side of the substrate away from the glass back panel.
[0076] Comparative Example 1:
[0077] A photovoltaic system comprises a 2.5 mm thick glass panel, a first packaging film, a battery, a second packaging film and a 2.5 mm thick glass back plate which are stacked in sequence, wherein a circular threading hole is opened in the center of the glass back plate, and the threading hole is not polished.
[0078] A junction box is provided on the back of the glass back panel. The junction box is a square structure and covers the wire threading hole.
[0079] Comparative Example 2:
[0080] A photovoltaic system has a structure that is substantially the same as that of comparative example 1, except that the threading holes are polished to ensure that the hole walls are smooth and free of burrs.
[0081] Comparative Example 3:
[0082] A photovoltaic system, the structure of which is basically the same as that of Comparative Example 2, except that:
[0083] A first buffer film is arranged between the second packaging film and the glass back plate, the first buffer film covers the threading holes, and the extension length of the first buffer film in the length direction of the back plate is one third of the length of the photovoltaic module.
[0084] Effect example:
[0085] The photovoltaic systems of Example 1 and Comparative Examples 1 to 3 were subjected to the MQT17hailtest55mm hail test in IEC61215, specifically, 45mm, 50mm and 55mm hail were used to impact the photovoltaic systems in turn, five samples were tested for each photovoltaic system, and the number of samples that passed each test was recorded to obtain the following table data:
[0086]
[0087] As shown in the above table, one of the conventional photovoltaic systems in comparative example 1 failed in the 45 mm hail test, and the remaining four all failed in the subsequent 50 mm hail test.
[0088] The photovoltaic system of Comparative Example 2 was polished with threading holes based on Comparative Example 1, which significantly improved its hail impact resistance. All five samples passed the 45mm hail test, and 4 passed the 50mm hail test, but all failed the 55mm hail test and could not meet the requirements.
[0089] The photovoltaic system of Comparative Example 3 added a sealant layer to protect the threading holes based on Comparative Example 2, further improving the impact performance. All five samples passed the 45mm and 50mm hail tests, but all failed the 55mm hail test and could not meet the requirements.
[0090] The photovoltaic system of Example 1 adopts a junction box structure including a circular substrate on the basis of Comparative Example 3, further improving the protection of the wire holes and the buffering performance. All five samples passed the 45mm, 50mm, and 55mm hail tests and can be used in special areas where hail of more than 50mm may occur, thereby increasing the application scope of the photovoltaic system.
[0091] For those skilled in the art, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.
[0092] The foregoing description of the specific exemplary embodiments of the present application is for the purpose of illustration and demonstration. These descriptions are not intended to limit the present application to the precise form disclosed, and it is clear that many changes and variations can be made based on the above teachings. The purpose of selecting and describing the exemplary embodiments is to explain the specific principles of the present application and its practical application, so that those skilled in the art can realize and utilize the various exemplary embodiments of the present application and various selections and changes. The scope of the present application is intended to be limited by the claims and their equivalents.
Claims
1. A junction box, characterized in that: Used to be installed on a photovoltaic module with threading holes arranged on the surface, the junction box includes a substrate and a box body arranged on the surface of the substrate, and the orthographic projection of the box body on the substrate only covers a partial area of the substrate; The substrate is used to fit the photovoltaic component so that the orthographic projections of the substrate and the box body on the surface of the photovoltaic component cover the threading holes.
2. The junction box according to claim 1, characterized in that: In the first direction, the extension length of the substrate is greater than or equal to the extension length of the box body; in the second direction, the extension length of the substrate is greater than the extension length of the box body; The first direction and the second direction are vertically distributed.
3. The junction box according to claim 2, characterized in that: An extension length of the box body in the first direction is greater than an extension length in the second direction.
4. The junction box according to claim 1, characterized in that: The outer periphery of the substrate is circular, and the box body extends radially from an outer edge on one side of the substrate surface to an outer edge on the other side.
5. A photovoltaic system, characterized in that: include: A photovoltaic module comprises a cover plate, a battery and a back plate which are stacked in sequence, wherein the back plate is provided with threading holes; The junction box according to any one of claims 1 to 4 is arranged on the surface of the back plate, and the substrate is arranged in close contact with the back plate so that the orthographic projection of the substrate and the box body on the surface of the back plate covers the threading hole; The first buffer film is arranged between the back plate and the substrate.
6. The photovoltaic system according to claim 5, characterized in that: The photovoltaic system further comprises: A first packaging film is arranged between the cover plate and the battery; The second packaging film is arranged between the battery and the back plate.
7. The photovoltaic system according to claim 6, characterized in that: The photovoltaic system further includes a second buffer film, which is arranged between the second packaging film and the back plate, covers the threading holes, and only covers a partial area of the second packaging film.
8. The photovoltaic system according to claim 7, characterized in that: The back plate is provided with a plurality of threading holes spaced apart in the width direction, the second buffer film is extended in the width direction of the back plate to cover the plurality of threading holes, and the extension length of the second buffer film in the length direction of the back plate is one quarter to one half of the length of the back plate; and / or, The hole wall of the threading hole is a smooth surface.
9. The photovoltaic system according to claim 7, characterized in that: The second buffer film is symmetrically arranged relative to the center line of the threading hole.
10. The photovoltaic system according to claim 5, characterized in that: The cover plate and the back plate are glass plates, and the thickness of the cover plate and the back plate is greater than or equal to 2.5 mm.