Junction box for photovoltaic system and photovoltaic system

Abstract

The utility model discloses a junction box used for a photovoltaic system and the photovoltaic system, the junction box used for the photovoltaic system comprises a box body, a plurality of terminals are arranged in the box body, the plurality of terminals are arranged along the length direction of the box body, at least one accommodating groove is formed in the side surface of one side, facing the center of the box body, of each terminal, and the accommodating grooves are communicated with the box body. The containing groove extends in the circumferential direction of the box body, a bus bar of the photovoltaic system is suitable for being connected with the side face of the side, facing the center of the box body, of the terminal, and at least one part of the containing groove is opposite to the bus bar in the thickness direction of the bus bar. According to the junction box for the photovoltaic system, two welding modes can be compatible, the applicability of the junction box is improved, the types of the junction box are reduced, the stock cost is reduced, and the stock cycle of the junction box is shortened.

Description

Technical Field

[0001] The utility model relates to the technical field of photovoltaics, in particular to a junction box for a photovoltaic system and a photovoltaic system. Background Art

[0002] The junction box is an important component in the photovoltaic system. It is used to connect loads to achieve power output and bypass protection, and to export the current generated by the photovoltaic modules of the photovoltaic system for users to use. The busbar (a tin-coated copper strip) of the photovoltaic module and the terminal of the junction box are usually connected by welding.

[0003] In the related art, tin-lead welding or laser welding can be used for welding. However, when different welding methods are used, different types of junction boxes need to be used, which increases the types and inventory of junction boxes, increases inventory costs, and prolongs the stocking cycle of junction boxes. Utility Model Content

[0004] The utility model aims to solve at least one of the technical problems existing in the prior art. To this end, one purpose of the utility model is to provide a junction box for a photovoltaic system, which is compatible with two welding methods, improves the applicability of the junction box, reduces the types of junction boxes, reduces inventory costs, and shortens the stocking cycle of the junction box.

[0005] Another object of the utility model is to provide a photovoltaic system using the junction box.

[0006] According to the first aspect of the utility model, a junction box for a photovoltaic system includes a box body, wherein the box body has a plurality of terminals, the plurality of terminals are arranged along the length direction of the box body, and at least one accommodating groove is formed on a side surface of the terminal facing the center of the box body, and the accommodating groove extends along the circumference of the box body. A bus bar of the photovoltaic system is suitable for being connected to a side surface of the terminal facing the center of the box body, and at least a portion of the accommodating groove is opposite to the bus bar along the thickness direction of the bus bar.

[0007] According to the junction box of the utility model, by providing a receiving groove on the surface of the terminal, the junction box can be compatible with both laser welding and tin-lead welding, thereby improving the applicability of the junction box, reducing the types of junction boxes, reducing inventory costs, and shortening the stocking cycle of the junction box. In addition, the receiving groove has a simple structure, stable performance, and is easy to produce and use, thereby reducing the production cost of the junction box.

[0008] According to some embodiments of the present invention, the accommodating groove is an annular groove.

[0009] According to some embodiments of the present invention, at least one partition is provided in the accommodating groove, and a side surface of the partition facing the center of the box body is flush with a side surface of the terminal facing the center of the box body.

[0010] According to some embodiments of the present invention, the width of the accommodating groove is a, and the depth of the accommodating groove is h, wherein a and h respectively satisfy: 0.1mm≤a≤1mm, 0.1≤h≤1mm.

[0011] According to some embodiments of the present invention, there are multiple accommodating grooves, and the multiple accommodating grooves are arranged at intervals along the radial direction of the accommodating grooves.

[0012] According to some embodiments of the present invention, the minimum distance between two adjacent accommodating grooves is d, wherein d satisfies: 0.2 mm≤d≤1 mm.

[0013] According to some embodiments of the present invention, the terminal is a copper piece and / or an aluminum piece.

[0014] According to some embodiments of the utility model, a protective layer is provided on a side surface of the terminal facing the center of the box body, and the protective layer is a tin layer or a nickel layer.

[0015] According to the second aspect of the present invention, the photovoltaic system includes a junction box, which is a junction box for a photovoltaic system according to the first aspect of the present invention; and a photovoltaic component, which includes a plurality of bus bars, and the plurality of bus bars are respectively connected to the plurality of terminals in a one-to-one correspondence.

[0016] According to some embodiments of the present invention, the bus bar and the terminal are laser welded or tin-lead welded.

[0017] Additional aspects and advantages of the present invention will be given in part in the following description, and in part will become apparent from the following description, or will be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0019] Figure 1 is a schematic diagram of a junction box according to an embodiment of the utility model;

[0020] Figure 2 yes Figure 1 The enlarged view of the circled section A;

[0021] Figure 3 is a schematic diagram of the assembly of a junction box and a bus bar of a photovoltaic system according to an embodiment of the utility model;

[0022] Figure 4 yes Figure 3 An enlarged view of the circled portion B.

[0023] Reference numerals:

[0024] 100. Junction box;

[0025] 1. box body; 11. terminal; 111. receiving groove;

[0026] 101. Bus bar. DETAILED DESCRIPTION

[0027] The embodiments of the present invention are described in detail below. The embodiments described with reference to the accompanying drawings are exemplary. Figure 1-Figure 4 A junction box 100 for a photovoltaic system (not shown) according to an embodiment of a first aspect of the utility model is described.

[0028] like Figure 1 and Figure 3 As shown, a junction box 100 for a photovoltaic system according to an embodiment of the first aspect of the utility model comprises a box body 1 .

[0029] Specifically, the box body 1 has a plurality of terminals 11, and the plurality of terminals 11 are arranged along the length direction of the box body 1 (for example Figure 1 The terminals 11 are arranged in the left and right directions as shown in the figure. In the description of the present utility model, "multiple" means two or more. The terminal 11 is formed with at least one receiving groove 111 on one side of the side facing the center of the box body 1. The receiving groove 111 extends along the circumference of the box body 1. The bus bar 101 of the photovoltaic system is suitable for being connected to the side of the terminal 11 facing the center of the box body 1, and at least a portion of the receiving groove 111 is opposite to the bus bar 101 along the thickness direction of the bus bar 101.

[0030] For example, in Figure 1 In the example, two terminals 11 are provided, and the two terminals 11 are spaced apart in the left-right direction, and the upper surface of the terminal 11 is a plane. The receiving groove 111 is formed on the upper side of the terminal 11, and the lower side of the busbar 101 of the photovoltaic system is connected to the upper side of the terminal 11, and the side of the receiving groove 111 close to the center of the box body 1 in the left-right direction (that is, at least a part of the receiving groove 111) is opposite to the busbar 101 in the upper and lower directions. When the busbar 101 is connected to the terminal 11, the positive busbar is connected to the positive terminal, and the negative busbar is connected to the negative terminal.

[0031] With such a configuration, the free end of the busbar 101 is pressed downward, and the lower side of the busbar 101 is closely fitted with the upper side of the terminal 11 (i.e., in direct contact), and laser welding can be used for connection, which is simple to operate, thereby improving the installation efficiency of the busbar 101 and the junction box 100. In addition, tin-lead welding can also be used. When the junction box 100 is manufactured, a tin-lead piece is prefabricated on the upper surface of the terminal 11 adjacent to the receiving groove 111, and the busbar 101 and the terminal 11 are welded using the tin-lead piece. During the welding process, the tin-lead piece melts, and the excess tin-lead piece can flow into the receiving groove 111. Due to the effect of surface tension, the receiving groove 111 can limit the flow range of the tin-lead piece, preventing the tin-lead piece from flowing into other areas of the box body 1, thereby effectively avoiding the occurrence of a short circuit, and further facilitating the normal use of the junction box 100 for a long time. Thus, the junction box 100 is compatible with two welding methods, so that during use, there is no need to prepare different junction boxes 100, which is convenient for use, improves the applicability of the junction box 100, and helps to reduce the types of junction boxes 100, reduce the amount of inventory, reduce the cost of inventory, and shorten the stocking period of the junction box 100. In addition, the accommodating groove 111 has a simple structure, stable performance, and is easy to produce and use, thereby reducing the production cost of the junction box 100.

[0032] According to the junction box 100 of the present invention, by providing the receiving groove 111 on the surface of the terminal 11, the junction box 100 can be compatible with both laser welding and tin-lead welding, thereby improving the applicability of the junction box 100, reducing the types of the junction box 100, reducing the inventory cost, and shortening the stocking period of the junction box 100. In addition, the receiving groove 111 has a simple structure, stable performance, and is easy to produce and use, thereby reducing the production cost of the junction box 100.

[0033] According to some embodiments of the present invention, referring to Figure 1 and Figure 2 , the receiving groove 111 is an annular groove. For example, Figure 1 and Figure 2 In the example, the cross-sectional shape of the receiving groove 111 can be rectangular. Therefore, when the tin-lead soldering method is adopted, after the tin-lead piece is melted, the molten tin-lead piece can flow into the receiving groove 111 along the circumferential direction, thereby effectively preventing the molten tin-lead piece from flowing to other areas of the box body 1 and avoiding a short circuit. In addition, the volume of the annular groove is large, thereby increasing the amount of the molten tin-lead piece to be accommodated, so as to be more conducive to the use of the junction box 100. For example, the cross-sectional shape of the receiving groove 111 can also be an oblong or elliptical shape, etc., so as to facilitate the use of the receiving groove 111. But it is not limited to this.

[0034] According to some embodiments of the utility model, at least one separator (not shown) is provided in the receiving groove 111, and the side surface of the separator facing the center of the box body 1 is flush with the side surface of the terminal 11 facing the center of the box body 1. For example, the upper side surface of the separator is flush with the upper side surface of the terminal 11, and the receiving groove 111 is an unclosed annular groove. In this way, when the tin-lead welding method is ensured, the molten tin-lead parts are prevented from flowing to other areas of the box body 1. The flatness of the upper surface of the terminal 11 is improved by the setting of the separator, thereby improving the tightness of the fit between the busbar 101 and the terminal 11 during the laser welding process, thereby improving the welding yield of the busbar 101 and the terminal 11. In addition, the separator increases the contact area between the busbar 101 and the terminal 11, thereby helping to improve the welding effect of the busbar 101 and the terminal 11, thereby improving the connection stability of the junction box 100 and the bus, and improving the performance of the photovoltaic system.

[0035] According to some embodiments of the present invention, referring to Figure 2 , the width of the receiving groove 111 is a, and the depth of the receiving groove 111 is h, wherein a and h respectively satisfy: 0.1mm≤a≤1mm, 0.1≤h≤1mm. For example, when the width a of the receiving groove 111 is less than 0.1mm, the volume of the receiving groove 111 is small, so that the content of the molten tin-lead parts contained in the receiving groove 111 is small, and the molten tin-lead parts are easily lost to other areas of the box body 1, thereby easily causing a short circuit. When the width a of the receiving groove 111 is greater than 1mm, the width of the receiving groove 111 is large, which increases the occupied area of ​​the receiving groove 111 on the upper surface of the terminal 11, thereby reducing the contact area between the terminal 11 and the busbar 101, and causing a gap between the busbar 101 and the surface of the terminal 11, thereby reducing the welding yield and the welding effect when laser welding is used.

[0036] When the depth h of the receiving groove 111 is less than 0.1 mm, the volume of the receiving groove 111 is small, so the content of the molten tin-lead parts contained in the receiving groove 111 is small, and the molten tin-lead parts are easily lost to other areas of the box body 1, so that a short circuit is easily caused. When the depth h of the receiving groove 111 is greater than 1 mm, the depth of the receiving groove 111 is large, and the bottom wall of the receiving groove 111 is thin, which reduces the structural strength. Therefore, during use, the bottom wall of the receiving groove 111 is easily broken, shortening the service life of the junction box 100.

[0037] Thus, by setting the width a of the receiving groove 111 and the height h of the receiving groove 111 to respectively satisfy: 0.1 mm ≤ a ≤ 1 mm, 0.1 ≤ h ≤ 1 mm, the size of the receiving groove 111 is reasonably set. On the one hand, the content of the molten tin-lead parts contained in the receiving groove 111 is increased, and the molten tin-lead parts are prevented from flowing to other areas of the box body 1, thereby avoiding a short circuit in the junction box 100, which helps the junction box 100 to be used normally for a long time. On the other hand, the occupied area of ​​the receiving groove 111 on the upper surface of the terminal 11 is reduced, thereby increasing the contact area between the terminal 11 and the bus bar 101, and avoiding a gap between the bus bar 101 and the surface of the terminal 11, thereby improving the welding yield and the welding effect when laser welding is used. In addition, the bottom wall thickness of the receiving groove 111 is also increased, and the structural strength is improved, so that during use, the bottom wall of the receiving groove 111 is avoided from being broken, and the service life of the junction box 100 is extended. For example, a = 0.2 mm, h = 0.3 mm, but not limited to this.

[0038] Further, refer to Figure 1 and Figure 2 There are multiple receiving grooves 111, and the multiple receiving grooves 111 are arranged at intervals along the radial direction of the receiving grooves 111. For example, Figure 1 and Figure 2 In the example, there are two receiving grooves 111, and the arrangement of the two receiving grooves 111 is roughly "return" shaped. The tin-lead piece is arranged on the inner peripheral side of the inner receiving groove 111, and the tin-lead piece can also be arranged on the inner peripheral side of the outer receiving groove 111. As a result, when the molten tin-lead piece flows out of the inner receiving groove 111, the outer surrounding receiving grooves 111 can limit the molten tin-lead piece, thereby enhancing the control ability of the flow range of the molten tin-lead piece, and further avoiding the possibility of the molten tin-lead piece flowing to other areas of the box body 1, and further avoiding the occurrence of a short circuit. It should be noted that the multiple receiving grooves 111 can be arranged at equal intervals or at unequal intervals, and the arrangement of the multiple receiving grooves 111 can be set according to the actual use situation to meet the actual use. Moreover, the sum of the volumes of the multiple receiving grooves 111 is less than the volume of the tin-lead piece. For example, there can be one to five receiving grooves 111, but it is not limited thereto.

[0039] According to some embodiments of the present invention, referring to Figure 1 and Figure 2, the minimum spacing between two adjacent receiving grooves 111 is d, where d satisfies: 0.2mm≤d≤1mm. For example, when the minimum spacing d between two adjacent receiving grooves 111 is less than 0.2mm, the spacing between two adjacent receiving grooves 111 is small. After the busbar 101 contacts the terminal 11, the gap between the busbar 101 and the terminal 11 increases, thereby reducing the welding yield when laser welding is used. When the minimum spacing d between two adjacent receiving grooves 111 is greater than 1mm, when the busbar 101 and the terminal 11 are welded by tin-lead welding, the busbar 101 will not be able to cover multiple receiving grooves 111 along the left and right directions. That is, part of the receiving groove 111 will exceed the welding area (such as Figure 1 The portion A shown in the middle circle) prolongs the flow path of the melted tin-lead piece, which is not conducive to the melted tin-lead piece flowing into the receiving groove 111. In addition, the number of receiving grooves 111 is also limited, and the number of receiving grooves 111 is reduced, thereby reducing the ability to control the flow range of the molten tin-lead piece, making it easy for the molten tin-lead piece to flow to other areas of the box body 1, which is prone to short circuit.

[0040] Thus, by setting the minimum spacing d between two adjacent receiving grooves 111 to satisfy 0.2mm≤d≤1mm, the minimum spacing between two adjacent receiving grooves 111 is reasonably set, and after the busbar 101 contacts the terminal 11, the gap between the busbar 101 and the terminal 11 is reduced, thereby helping to improve the welding yield when laser welding is used. In addition, it is easy for the busbar 101 to cover multiple receiving grooves 111 in the left and right directions, and it is easy for the receiving grooves 111 to be located in the welding area, thereby helping to improve the utilization rate of the receiving grooves 111. In addition, it is easy to control the number of receiving grooves 111, and increase the number of receiving grooves 111, thereby helping to improve the ability to control the flow range of molten tin-lead parts, avoiding the molten tin-lead parts from flowing to other areas of the box body 1, and thus avoiding short circuits. For example, d=0.5mm, but not limited to this.

[0041] According to some embodiments of the utility model, the terminal 11 is a copper part and / or an aluminum part. The configuration of the terminal 11 includes the following situations: First, when the terminal 11 is a copper part, the copper part has good ductility and high conductivity, which facilitates the molding of the terminal 11 and reduces the difficulty of producing the terminal 11. Second, when the terminal 11 is an aluminum part, the conductivity of the terminal 11 is also improved, thereby improving the performance of the terminal 11. Aluminum parts have ductility and good conductivity, and the price of aluminum parts is low, thereby reducing the production cost of the terminal 11. Third, when the terminal 11 is an aluminum part and a copper part, the structural strength of the terminal 11 is increased, which helps to extend the service life of the terminal 11.

[0042] According to some embodiments of the utility model, a protective layer (not shown) is provided on the side surface of the terminal 11 facing the center of the box body 1, and the protective layer is a tin layer or a nickel layer. For example, the protective layer is located on the upper side surface of the terminal 11. Thus, the protective layer can protect the terminal 11 and prevent the terminal 11 from corrosion, thereby helping to extend the service life of the terminal 11. In addition, the tin layer will form a protective film in the air, thereby helping to improve the stability of the protective layer, and further helping to improve the protective effect of the protective layer on the terminal 11. In addition, the nickel layer has corrosion resistance, thereby improving the corrosion resistance of the protective layer and improving the protective ability of the protective layer on the terminal 11.

[0043] Optionally, the receiving groove 111 is formed by die stamping, thereby reducing the difficulty of forming the receiving groove 111 , thereby helping to improve the production efficiency of the receiving groove 111 , and further improving the production efficiency of the junction box 100 .

[0044] A photovoltaic system (not shown) according to an embodiment of the second aspect of the utility model comprises a junction box 100 and a photovoltaic assembly (not shown).

[0045] Specifically, the junction box 100 is a junction box 100 for a photovoltaic system according to the embodiment of the first aspect of the utility model, and the photovoltaic module includes a plurality of bus bars 101, and the plurality of bus bars 101 are respectively connected to a plurality of terminals 11 in a one-to-one correspondence. For example, the free end of the bus bar 101 passes through the bottom wall of the box body 1, and the portion of the bus bar 101 located on the upper side of the terminal 11 is connected to the upper surface of the terminal 11, the positive bus bar 101 is connected to the positive terminal 11 correspondingly, the negative bus bar 101 is connected to the negative terminal 11 correspondingly, the positive terminal 11 is located on the left side of the box body 1, and the negative terminal 11 is located on the right side of the box body 1. As a result, it is convenient to connect the power generated inside the photovoltaic module to the external line through the junction box 100, which helps the photovoltaic system to be used normally for a long time.

[0046] According to some embodiments of the utility model, the busbar 101 and the terminal 11 are laser welded or tin-lead welded. Thus, the lower side of the busbar 101 and the upper side of the terminal 11 can be laser welded, which helps to improve the welding pass rate. Moreover, laser welding is more environmentally friendly and easy to maintain. In addition, during the tin-lead welding process, the tin-lead parts flow under heat, which helps to improve the quality of welding.

[0047] The junction box 100 and other structures and operations of the photovoltaic system according to the embodiment of the present invention are known to those skilled in the art and will not be described in detail here.

[0048] In the description of the present invention, it should be understood that the terms "center", "length", "width", "thickness", "up", "down", "left", "right", "horizontal", "top", "bottom", "inside", "outside", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0049] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example.

[0050] Although the embodiments of the present invention have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A junction box for a photovoltaic system, characterized in that: It includes a box body, which has a plurality of terminals, and the plurality of terminals are arranged along the length direction of the box body. At least one accommodating groove is formed on a side surface of the terminal facing the center of the box body, and the accommodating groove extends along the circumference of the box body. The bus bar of the photovoltaic system is suitable for being connected to the side surface of the terminal facing the center of the box body, and at least a portion of the accommodating groove is opposite to the bus bar along the thickness direction of the bus bar.

2. The junction box for a photovoltaic system according to claim 1, characterized in that: The accommodating groove is an annular groove.

3. The junction box for a photovoltaic system according to claim 2, characterized in that: At least one partition is disposed in the accommodating groove, and a side surface of the partition facing the center of the box body is flush with a side surface of the terminal facing the center of the box body.

4. The junction box for a photovoltaic system according to claim 1, characterized in that: The width of the accommodating groove is a, and the depth of the accommodating groove is h, wherein a and h respectively satisfy: 0.1 mm≤a≤1 mm, 0.1≤h≤1 mm.

5. The junction box for a photovoltaic system according to claim 1, characterized in that: There are a plurality of the accommodating grooves, and the plurality of the accommodating grooves are arranged at intervals along the radial direction of the accommodating groove.

6. The junction box for a photovoltaic system according to claim 5, characterized in that: The minimum distance between two adjacent accommodating grooves is d, wherein d satisfies: 0.2 mm ≤ d ≤ 1 mm.

7. The junction box for a photovoltaic system according to claim 1, characterized in that: The terminal is a copper part and / or an aluminum part.

8. The junction box for a photovoltaic system according to any one of claims 1 to 7, characterized in that: A protective layer is provided on a side surface of the terminal facing the center of the box body, and the protective layer is a tin layer or a nickel layer.

9. A photovoltaic system, characterized in that: include A junction box, wherein the junction box is a junction box for a photovoltaic system according to any one of claims 1 to 8; A photovoltaic assembly, wherein the photovoltaic assembly comprises a plurality of bus bars, and the plurality of bus bars are respectively connected to the plurality of terminals in a one-to-one correspondence.

10. The photovoltaic system according to claim 9, characterized in that: The bus bar and the terminal are laser welded or tin-lead welded.

Images