Photovoltaic junction box and laminated photovoltaic module

Abstract

The utility model discloses a photovoltaic junction box and a laminated photovoltaic assembly, the laminated photovoltaic assembly comprises a first battery layer and a second battery layer located on the first battery layer, and the photovoltaic junction box comprises a box body and a DC / DC converter located in the box body; wherein the input positive electrode of the DC / DC converter is connected with the output positive electrode of the second battery layer, the input negative electrode of the DC / DC converter is connected with the output negative electrode of the second battery layer, the output positive electrode of the DC / DC converter is connected with the output positive electrode of the first battery layer, and the output negative electrode of the DC / DC converter is connected with the output negative electrode of the first battery layer. Through a group of photovoltaic junction boxes provided with DC / DC converters, voltage matching of two battery layers is realized in the photovoltaic junction boxes, electric energy of the two battery layers is output in parallel through the photovoltaic junction boxes, other converters, junction boxes and cables do not need to be additionally arranged outside the laminated assembly, the assembly cost is saved, the assembly structure is simpler, and the cost is reduced. And the system is more convenient to connect, install and maintain.

Description

Technical Field

[0001] The utility model belongs to the technical field of photovoltaic power generation, and in particular relates to a photovoltaic junction box and a laminated photovoltaic component. Background Art

[0002] In the existing perovskite / crystalline silicon stacked module design, the circuits of the perovskite layer battery module and the crystalline silicon layer battery module are independent. The perovskite layer battery module has a higher open-circuit voltage than the crystalline silicon layer battery module. There is a problem of mismatch between the operating voltages of the perovskite layer and the crystalline silicon layer. It is often necessary to use two or more sets of junction boxes to output the electrical energy of the two layers of battery modules separately, resulting in the installation of more converters, junction boxes and cables outside the module, increasing the cost of materials, manufacturing and installation and the complexity of the system.

[0003] Therefore, in order to solve the above technical problems, it is necessary to provide a photovoltaic junction box and a laminated photovoltaic module. Utility Model Content

[0004] The purpose of the utility model is to provide a photovoltaic junction box and a laminated photovoltaic module, which can solve the problem of voltage mismatch between two battery layers of the laminated photovoltaic module through a set of photovoltaic junction boxes provided with a DC / DC converter.

[0005] In order to achieve the above-mentioned purpose, the technical solution provided by a specific embodiment of the present invention is as follows:

[0006] A photovoltaic junction box is applied to a laminated photovoltaic module, wherein the laminated photovoltaic module comprises a first battery layer and a second battery layer located above the first battery layer, wherein the photovoltaic junction box comprises a box body and a DC / DC converter located inside the box body; wherein,

[0007] The input positive pole of the DC / DC converter is connected to the output positive pole of the second battery layer, the input negative pole of the DC / DC converter is connected to the output negative pole of the second battery layer, the output positive pole of the DC / DC converter is connected to the output positive pole of the first battery layer, and the output negative pole of the DC / DC converter is connected to the output negative pole of the first battery layer.

[0008] In one or more embodiments of the present invention, a first diode is provided inside the box body of the photovoltaic junction box; wherein,

[0009] An anode of the first diode is connected to a negative electrode of a group of battery strings in the first battery layer, and a cathode of the first diode is connected to a positive electrode of a group of battery strings in the first battery layer.

[0010] Another specific embodiment of the present invention provides a technical solution as follows:

[0011] A laminated photovoltaic module, comprising a first battery layer and a second battery layer located above the first battery layer, the laminated photovoltaic module also comprising a first photovoltaic junction box, the first photovoltaic junction box comprising a box body and a DC / DC converter located inside the box body;

[0012] The positive input electrode of the DC / DC converter is connected to the positive output electrode of the second battery layer, the negative input electrode of the DC / DC converter is connected to the negative output electrode of the second battery layer, the positive output electrode of the DC / DC converter is connected to the positive output electrode of the first battery layer, and the negative output electrode of the DC / DC converter is connected to the negative output electrode of the first battery layer.

[0013] In one or more embodiments of the present invention, the first battery layer includes a first group of battery strings, and a first diode is provided inside the box body of the first photovoltaic junction box; wherein,

[0014] The cathode of the first diode is connected to the positive electrode of the first battery string, and the anode of the first diode is connected to the negative electrode of the first battery string.

[0015] In one or more embodiments of the present invention, the first battery layer includes a first battery string, a second battery string, and a third battery string; the laminated photovoltaic module further includes a second photovoltaic junction box and a third photovoltaic junction box; the second photovoltaic junction box includes a box body and a second diode located inside the box body; the third photovoltaic junction box includes a box body and a third diode located inside the box body; wherein,

[0016] The positive electrode of the second battery string is the output positive electrode of the first battery layer, and the negative electrode of the third battery string is the output negative electrode of the first battery layer;

[0017] The cathode of the second diode is connected to the output positive electrode of the first battery layer, and the anode of the second diode is connected to the negative electrode of the second battery string;

[0018] The anode of the third diode is connected to the output negative electrode of the first battery layer, and the cathode of the third diode is connected to the positive electrode of the third battery string.

[0019] In one or more embodiments of the present invention, the first battery layer further includes a first bus bar and a second bus bar; wherein,

[0020] The first end of the first bus bar is connected to the negative electrode of the second battery string, and the second end of the first bus bar is connected to the positive electrode of the first battery string;

[0021] The first end of the second bus bar is connected to the negative electrode of the first battery string, and the second end of the second bus bar is connected to the positive electrode of the third battery string.

[0022] In one or more embodiments of the present invention, a first cable is provided on the second photovoltaic junction box, and one end of the first cable is connected to the cathode of the second diode;

[0023] The third photovoltaic junction box is provided with a second cable, and one end of the second cable is connected to the anode of the third diode.

[0024] In one or more embodiments of the present invention, the first cell layer is a crystalline silicon cell layer, comprising a plurality of crystalline silicon cell slices distributed in an array;

[0025] The second battery layer is a perovskite battery layer, which includes a plurality of perovskite battery cells distributed in an array.

[0026] In one or more embodiments of the present invention, the photovoltaic module further includes front glass, a first packaging film, a second packaging film and back glass; wherein,

[0027] The front glass is located above the perovskite cell layer;

[0028] The first encapsulation film is located between the perovskite cell layer and the crystalline silicon cell layer;

[0029] The second encapsulation film is located between the crystalline silicon cell layer and the back glass;

[0030] The back glass is located below the crystalline silicon cell layer.

[0031] In one or more embodiments of the present invention, the first photovoltaic junction box, the second photovoltaic junction box and the third photovoltaic junction box are located on one side edge of the back side of the laminated photovoltaic module, and the first photovoltaic junction box is located between the second photovoltaic junction box and the third photovoltaic junction box.

[0032] Compared with the existing technology, the photovoltaic junction box and laminated photovoltaic module of the present invention achieve voltage matching of the two battery layers inside the photovoltaic junction box through a set of photovoltaic junction boxes equipped with DC / DC converters, and output the power of the two battery layers in parallel through the photovoltaic junction box. There is no need to add other converters, junction boxes and cables outside the laminated module, which saves module costs, has a simpler module structure, and is more convenient for system connection, installation and maintenance.

[0033] The utility model also realizes hot spot protection by means of the diodes provided in the photovoltaic junction box. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0035] Figure 1 This is a schematic diagram of a photovoltaic junction box in Example 1 of the present utility model;

[0036] Figure 2 This is a schematic diagram of a laminated photovoltaic module in Example 2 of the present utility model;

[0037] Figure 3 This is a schematic diagram of the first cell layer of the laminated photovoltaic module in Example 2 of the present utility model;

[0038] Figure 4 This is a schematic diagram of the second cell layer of the laminated photovoltaic module in Example 2 of the present utility model;

[0039] Figure 5 This is a schematic diagram of a photovoltaic junction box of a laminated photovoltaic module in Example 2 of the present utility model;

[0040] Figure 6 This is a schematic diagram of the photovoltaic junction box of the laminated photovoltaic module in Example 2 of the present utility model. DETAILED DESCRIPTION

[0041] In order to enable those skilled in the art to better understand the technical solutions of the present invention, the following will be combined with the drawings of the embodiments of the present invention to clearly and completely describe the technical solutions of the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0042] The terms "coupled," "connected," or "connected" as used in this specification encompass both direct and indirect connections. An indirect connection is a connection made through an intermediate medium, such as an electrically conductive medium, which may have parasitic inductance or capacitance. An indirect connection may also include a connection through other active or passive devices to achieve the same or similar functional purpose, such as a connection through circuits or components such as switches and follower circuits. Furthermore, in this utility model, terms such as "first" and "second" are primarily used to distinguish one technical feature from another and do not necessarily require or imply a specific relationship, quantity, or order between these technical features.

[0043] Example 1:

[0044] like Figure 1 As shown, the photovoltaic junction box 1 in this embodiment is applied to a laminated photovoltaic module, which includes a first battery layer 5 and a second battery layer 4 located above the first battery layer 5. The photovoltaic junction box 1 includes a box body and a DC / DC converter 15 located inside the box body.

[0045] Specifically, the input positive electrode 11 of the DC / DC converter 15 in this embodiment is connected to the output positive electrode 41 of the second battery layer 4, the input negative electrode 12 of the DC / DC converter is connected to the output negative electrode 42 of the second battery layer 4, the output positive electrode 13 of the DC / DC converter 15 is connected to the output positive electrode 51 of the first battery layer 5, and the output negative electrode 14 of the DC / DC converter is connected to the output negative electrode 52 of the first battery layer 5.

[0046] The voltage value of the electric energy generated by the second battery layer 4 is matched with the voltage value of the electric energy generated by the first battery layer 5 through a DC / DC converter and then output in parallel.

[0047] A first diode D1 is installed inside the photovoltaic junction box 1. The anode 16 of the first diode D1 is connected to the negative electrode of a group of battery strings in the first battery layer 5, and the cathode 15 of the first diode D1 is connected to the positive electrode of a group of battery strings in the first battery layer 5. It is understood that the first diode D1 acts as a bypass diode, providing hot spot protection.

[0048] Example 2:

[0049] like Figure 2 As shown, the laminated photovoltaic module in this embodiment includes a first cell layer 5 and a second cell layer 4 located on the first cell layer 5. In addition, the laminated photovoltaic module in this embodiment also includes front glass 6, a first encapsulation film 7, a second encapsulation film 8 and back glass 9.

[0050] Among them, the front glass 6 is located above the second battery layer 4; the first packaging film 7 is located between the second battery layer 4 and the first battery layer 5; the second packaging film 8 is located between the first battery layer 5 and the back glass 9; and the back glass 9 is located below the first battery layer 5.

[0051] like Figure 3As shown, the first cell layer 5 in this embodiment is a crystalline silicon cell layer, comprising a plurality of crystalline silicon cells arranged in an array. Specifically, the first cell layer 5 includes a first cell string, a second cell string, a third cell string, a first bus bar 53, a second bus bar 54, and a third bus bar 56. Each cell string includes an even number of columns of crystalline silicon cells arranged in series. Furthermore, each column of crystalline silicon cells is longitudinally connected in series using photovoltaic ribbons 55, and each two columns of crystalline silicon cells are connected in series using bus bars.

[0052] The photovoltaic welding ribbon 55 in this embodiment may be a tinned copper ribbon. The busbar in this embodiment is also called a laminated busbar, which is a power module electrical connection component with a multi-layer laminated structure.

[0053] In this embodiment, each battery string includes two rows of crystalline silicon cells. The positive electrode of each battery string is the positive electrode of the first crystalline silicon cell connected in series in the battery string, and the negative electrode of each battery string is the negative electrode of the last crystalline silicon cell connected in series in the battery string. Figure 3 As shown, the two columns of crystalline silicon cells in each battery string are connected via a third bus bar 56 .

[0054] like Figure 3 As shown, in this embodiment, the first, second, and third battery strings are arranged in parallel and connected in series. The positive electrode of the second battery string is the output positive electrode 51 of the first battery layer, and the negative electrode of the second battery string is connected to the first end of the first bus bar 53. The positive electrode of the first battery string is connected to the second end of the first bus bar 53, and the negative electrode of the first battery string is connected to the first end of the second bus bar 54. The positive electrode of the third battery string is connected to the second end of the second bus bar 54, and the negative electrode of the third battery string is the output negative electrode 52 of the first battery layer.

[0055] like Figure 4 As shown, in one embodiment, the second battery layer 4 is a perovskite battery layer, comprising a plurality of array-distributed perovskite battery cells. The second battery layer 4 is provided with an output positive electrode 41 and an output negative electrode 42.

[0056] like Figure 5 As shown, the laminated photovoltaic module of this embodiment includes three photovoltaic junction boxes: a first photovoltaic junction box 1, a second photovoltaic junction box 2, and a third photovoltaic junction box 3. The first, second, and third photovoltaic junction boxes 1, 2, and 3 are located on one edge of the back side of the laminated photovoltaic module, with the first photovoltaic junction box 1 positioned between the second and third photovoltaic junction boxes 2, 3. It will be appreciated that the first, second, and third photovoltaic junction boxes 1, 2, and 3 constitute a set of three-part photovoltaic junction boxes. Compared to existing technologies that require two or more sets of junction boxes, this application only requires one set of junction boxes to achieve voltage matching between the two battery layers.

[0057] like Figure 6 As shown, the first photovoltaic junction box 1 is identical to that of embodiment 1 and will not be described in detail here. The second photovoltaic junction box 2 includes a box body and a second diode D2 located inside the box body, and the third photovoltaic junction box 3 includes a box body and a third diode D3 located inside the box body.

[0058] In this embodiment, the first diode D1 is connected in reverse parallel to the first battery string, the second diode D2 is connected in reverse parallel to the second battery string, and the third diode D3 is connected in reverse parallel to the third battery string.

[0059] Specifically, the cathode 15 of the first diode D1 is connected to the positive electrode of the first battery string, and the anode 16 of the first diode D1 is connected to the negative electrode of the first battery string.

[0060] The cathode 21 of the second diode D2 is connected to the output positive electrode 51 of the first battery layer, and the anode 22 of the second diode D2 is connected to the negative electrode of the second battery string.

[0061] The anode 32 of the third diode D3 is connected to the output negative electrode 52 of the first battery layer, and the cathode 31 of the third diode D3 is connected to the positive electrode of the third battery string. It can be understood that the second diode D2 and the third diode D3 act as bypass diodes to provide hot spot protection.

[0062] like Figure 5 and Figure 6 As shown, in this embodiment, the second photovoltaic junction box 2 is provided with a first cable 23, one end of which is connected to the cathode 21 of the second diode. It is understood that the other end of the first cable 23 serves as the positive output terminal of the laminated photovoltaic module. The third photovoltaic junction box 3 is provided with a second cable 33, one end of which is connected to the anode 32 of the third diode. It is understood that the other end of the second cable 33 serves as the negative output terminal of the laminated photovoltaic module.

[0063] The perovskite cell layer in this embodiment has a higher open circuit voltage than the crystalline silicon cell layer. The DC / DC converter provided in the first photovoltaic junction box 1 reduces the voltage value of the electric energy generated by the perovskite cell layer so that the voltage value of the electric energy generated by the perovskite cell layer matches the voltage value of the electric energy generated by the crystalline silicon cell layer.

[0064] It can be seen from the above technical solutions that the present invention has the following beneficial effects:

[0065] The utility model uses a photovoltaic junction box equipped with a DC / DC converter to achieve voltage matching of the two battery layers inside the photovoltaic junction box, and outputs the power of the two battery layers in parallel through the photovoltaic junction box. There is no need to add other converters, junction boxes and cables outside the stacked components, which saves component costs, makes the component structure simpler, and makes system connection, installation and maintenance more convenient.

[0066] The utility model also realizes hot spot protection through the diodes in the photovoltaic junction box.

[0067] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the present invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be encompassed within the present invention. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

[0068] In addition, 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.

Claims

1. A photovoltaic junction box, applied to a laminated photovoltaic module, wherein the laminated photovoltaic module comprises a first battery layer and a second battery layer located above the first battery layer, characterized in that: The photovoltaic junction box includes a box body and a DC / DC converter located inside the box body; wherein, The input positive pole of the DC / DC converter is connected to the output positive pole of the second battery layer, the input negative pole of the DC / DC converter is connected to the output negative pole of the second battery layer, the output positive pole of the DC / DC converter is connected to the output positive pole of the first battery layer, and the output negative pole of the DC / DC converter is connected to the output negative pole of the first battery layer.

2. The photovoltaic junction box according to claim 1, characterized in that: The photovoltaic junction box is provided with a first diode inside the box body; wherein, An anode of the first diode is connected to a negative electrode of a group of battery strings in the first battery layer, and a cathode of the first diode is connected to a positive electrode of a group of battery strings in the first battery layer.

3. A laminated photovoltaic module, comprising a first battery layer and a second battery layer located above the first battery layer, characterized in that: The laminated photovoltaic assembly further includes a first photovoltaic junction box, which includes a box body and a DC / DC converter located inside the box body; The positive input electrode of the DC / DC converter is connected to the positive output electrode of the second battery layer, the negative input electrode of the DC / DC converter is connected to the negative output electrode of the second battery layer, the positive output electrode of the DC / DC converter is connected to the positive output electrode of the first battery layer, and the negative output electrode of the DC / DC converter is connected to the negative output electrode of the first battery layer.

4. The laminated photovoltaic module according to claim 3, characterized in that: The first battery layer includes a first group of battery strings, and a first diode is provided inside the box body of the first photovoltaic junction box; wherein, The cathode of the first diode is connected to the positive electrode of the first battery string, and the anode of the first diode is connected to the negative electrode of the first battery string.

5. The laminated photovoltaic module according to claim 3, characterized in that: The first battery layer includes a first battery string, a second battery string, and a third battery string. The laminated photovoltaic module also includes a second photovoltaic junction box and a third photovoltaic junction box. The second photovoltaic junction box includes a box body and a second diode located inside the box body. The third photovoltaic junction box includes a box body and a third diode located inside the box body. The positive electrode of the second battery string is the output positive electrode of the first battery layer, and the negative electrode of the third battery string is the output negative electrode of the first battery layer; The cathode of the second diode is connected to the output positive electrode of the first battery layer, and the anode of the second diode is connected to the negative electrode of the second battery string; The anode of the third diode is connected to the output negative electrode of the first battery layer, and the cathode of the third diode is connected to the positive electrode of the third battery string.

6. The laminated photovoltaic module according to claim 5, characterized in that: The first battery layer further includes a first bus bar and a second bus bar; wherein, The first end of the first bus bar is connected to the negative electrode of the second battery string, and the second end of the first bus bar is connected to the positive electrode of the first battery string; The first end of the second bus bar is connected to the negative electrode of the first battery string, and the second end of the second bus bar is connected to the positive electrode of the third battery string.

7. The laminated photovoltaic module according to claim 5, characterized in that: The second photovoltaic junction box is provided with a first cable, one end of the first cable is connected to the cathode of the second diode; The third photovoltaic junction box is provided with a second cable, and one end of the second cable is connected to the anode of the third diode.

8. The laminated photovoltaic module according to claim 3, characterized in that: The first cell layer is a crystalline silicon cell layer, comprising a plurality of crystalline silicon cell slices distributed in an array; The second battery layer is a perovskite battery layer, which includes a plurality of perovskite battery cells distributed in an array.

9. The laminated photovoltaic module according to claim 8, characterized in that: The laminated photovoltaic module further includes front glass, a first packaging film, a second packaging film and back glass; wherein, The front glass is located above the perovskite cell layer; The first encapsulation film is located between the perovskite cell layer and the crystalline silicon cell layer; The second encapsulation film is located between the crystalline silicon cell layer and the back glass; The back glass is located below the crystalline silicon cell layer.

10. The laminated photovoltaic module according to claim 5, characterized in that: The first photovoltaic junction box, the second photovoltaic junction box and the third photovoltaic junction box are located at one side edge of the back side of the laminated photovoltaic assembly, and the first photovoltaic junction box is located between the second photovoltaic junction box and the third photovoltaic junction box.

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