WO2023025631A1

WO2023025631A1 - Photovoltaic module and connection assembly for a photovoltaic module

Info

Publication number: WO2023025631A1
Application number: PCT/EP2022/072943
Authority: WO
Inventors: Matthias Bönsch; Torsten Wünsche; Torsten Jung; Torsten Diekmann; Christopher Smith
Original assignee: Weidmüller Interface GmbH & Co. KG
Priority date: 2021-08-25
Filing date: 2022-08-17
Publication date: 2023-03-02
Also published as: DE102021122010A1

Abstract

The invention relates to a connection assembly (10) for a photovoltaic module (1), the photovoltaic module having at least one cell assembly, which can be externally contacted at at least two contacts, and the connection assembly comprising at least two connection sockets (11), wherein, within the connection sockets (11), connection cables (12) can be connected to the contacts of the photovoltaic module (1). The connection assembly (10) is characterized in that, between each pair of the connection sockets (11), a connecting cable (13) extends, into which a bypass diode (15) is inserted. The invention also relates to a photovoltaic module (1) having a connection assembly (10) of this type.

Description

Photovoltaic module and connection arrangement for a photovoltaic module

The invention relates to a connection arrangement for a photovoltaic module (PV module) which has at least one cell arrangement which can be contacted externally at at least two contacts. The connection arrangement comprises at least two connection sockets, within which connection cables can be connected to the contacts of the PV module.

PV modules, e.g. B. for mounting on a house roof or in outdoor systems, usually have a plurality of photovoltaic cells (PV cells), which are connected in series and / or parallel form at least one cell array that can be contacted externally via connecting cables. PV modules often have a number of such cell arrangements which are connected in series within the PV module. In this case, each of the cell configurations is usually led out of the module with its end connections in order to connect a so-called “bypass diode” in parallel with each cell configuration. The bypass diodes direct current past shaded or defective cell arrays. Without the bypass diodes, shading or a defect in one of the cell arrays of the module would reduce the current flow through the entire module, even if the other cell arrays in the module or other modules connected in series with the module are not shaded or defective.

PV modules are known from the prior art in which connections of the existing cell arrangements (usually of three cell arrangements) can be contacted adjacent to one another on a rear side of the PV module in a common connection area. The contacts can, for example, be non-insulated contact strips on the rear side of the PV modules, which is otherwise covered by an insulating layer. A junction box is placed over the contact area, for example glued on, within which the bypass diodes are arranged and make contact with the contact surfaces of the PV module. In addition, two connection cables lead to the junction box mentioned, which are connected to the outer contacts of the series-connected cell arrangements and via which the PV module is connected externally.

A PV module with such a connection arrangement is described, for example, in an exemplary embodiment in publication US 2016/0141435 A1. In a further exemplary embodiment, the publication describes a PV module in which the contact surfaces of different cell arrangements are not combined into one shared connection area on the rear of the PV module, but in several different positions. In this case, each of the connection areas is covered with a socket that accommodates a bypass diode. At least two of the sockets function as a connection socket, as described above, in that a connection cable for the external connection of the PV module leads to these sockets and is connected to one of the cell arrangements inside the socket. A further exemplary embodiment describes that the bypass diodes can also be integrated into the PV module, specifically into the stack of layers of the PV module.

An arrangement of the bypass diodes in one or more of the junction boxes complicates their structure and their assembly. The arrangement of the bypass diodes in the stack of layers of the PV module is advantageous with regard to the design of the junction boxes, but complicates the construction of the PV modules.

It is an object of the present invention to create a connection arrangement for a PV module and a PV module with a connection arrangement in which neither the structure of the PV module itself nor the structure of the junction boxes is complicated by the bypass diodes.

This object is achieved by a connection arrangement for a PV module or a PV module with such a connection arrangement with the respective features of the independent claims. Advantageous refinements and developments are the subject matter of the dependent claims.

A connection arrangement according to the invention of the type mentioned at the outset is characterized in that a connection cable, in which a bypass diode is looped, runs between each two of the connection boxes.

According to the invention, the bypass diode is therefore not arranged in the junction box itself, which complicates its structure, nor is it integrated in the stack of layers of the PV module, which makes its structure more complex. Instead, a connection cable containing the bypass diode is routed externally from the stack of layers of the PV module between two junction boxes. The junction box itself can be designed to be very compact and material-saving, since it only has to accommodate the connection between the connecting cable and, if applicable, the connecting cable and the contact on the back of the PV module. Looping the bypass diode into the connection cable can also done compact and space-saving, especially since suitable diodes are available with axially arranged terminals whose diameter is of a comparable size as that of a suitable connecting cable. The diode then represents little more than a thickening within the connecting cable. No separate attachment is required for the bypass diode, since it is carried by the connecting cable.

If the PV module has a plurality of cell arrangements, the connection arrangement also comprises a plurality of connection sockets which are connected to one another in a chain-like manner via connecting cables, the connection cables being connected to two connection sockets on the outside of the chain.

In an advantageous embodiment of the connection arrangement, the connection boxes each have a contact element that can be connected to the contacts of the PV module. The contacts of the PV module can be exposed contact strips on the back of the PV module, for example. In that case the contact element is, for example, soldered or welded, for example by spot welding, onto the contact strip. A spring contact, in particular a double spring contact, can also be used. The contacts of the PV module can also be (protruding) connection contacts that are already attached to exposed contact strips. In this case, the contact element of the junction box can be a tulip contact or another plug-in contact, for example. A (protruding) connection contact can also be contacted via a spring contact or a welded or soldered contact.

In a further advantageous embodiment of the connection arrangement, the connection sockets have at least one insulation-penetrating contact for connection to the connection cable and/or the connection cable. A connection to the cables can be established easily and in a space-saving manner. In alternative configurations, a connection can also be produced by a crimping, soldering, welding or caulking process with a cable end that is then stripped in each case.

In a further advantageous embodiment of the connection arrangement, the connection cable and a section of the connection cable (or else two sections of two connection cables) are formed by a cable that runs through one of the connection boxes. This configuration is particularly advantageous in connection with the insulation-piercing contact. In a further advantageous embodiment of the connection arrangement, the at least one bypass diode and adjacent cable ends of sections of the connecting cable are encapsulated with a casting compound. The bypass diode is only a thickening in the connection cable and is protected and arranged in a compact manner. Good cooling of the bypass diode is also ensured if the potting compound is a good heat conductor.

In a PV module according to the invention, the contacts of the at least one cell arrangement are connected to one another and to connection cables via such a connection arrangement. The advantages mentioned in connection with the connection arrangement result.

The invention is explained in more detail below using an exemplary embodiment with the aid of figures. The figures show:

1a, 1b each show an isometric view of a PV module with contact surfaces (FIG. 1a) or connection contacts (FIG. 1b) on its rear side;

2a, 2b show an overall view and a detailed view of the PV module according to FIG. 1b and a connection arrangement before the connection arrangement is installed;

3a, 3b representations according to FIGS. 2a and 2b after the connection arrangement has been installed on the PV module; and

4a-c show various additional views of the area of the PV module shown in FIG. 3b.

In FIGS. 1a and 1b, a PV module 1 is first shown in an isometric representation. The PV module 1 has a frame 2 and the actual module structure, which is also referred to as a layer structure or layer stack in the context of this application. Only one rear side 3 of this module structure can be seen in the representation of FIGS. 1a and 1b.

The PV module 1 has a plurality of PV cells, which cannot be seen individually here. B. traces are connected to each other. The back 3 is covered with an insulating layer covered, this insulating layer being exposed at selected points to allow contacting. FIG. 1a shows the PV module 1 with such exposed contact surfaces 4. There are four of the contact surfaces 4, each representing the end taps of three cell arrangements connected in series. In other words, two adjacent contact areas 4 are each the end taps of one of the cell arrangements. A first cell arrangement can be contacted, for example, via the two contact surfaces 4 on the left. It is internally connected in series with a second cell arrangement, which can be contacted via the two middle contact surfaces 4 . A third cell arrangement, which is also connected in series with the two cell arrangements, can be contacted via the two right-hand contact surfaces 4 . It is noted that the number of three cell arrangements connected in series with one another in the illustrated exemplary embodiment is purely exemplary. The connection arrangement presented within the scope of this application can be used for any number of cell arrangements connected in series with one another. The individual cell arrangements themselves generally have a plurality of cells which are in turn connected to one another in series and/or in parallel.

In the exemplary embodiment of FIG. 1b, connection contacts 5 are mounted on the contact surfaces 4, for example soldered or welded on, e.g. B. in a spot welding process. The connection arrangement described below is designed in such a way that it makes contact with the connection contacts 5 according to FIG. However, it is also conceivable to design the connection arrangement in such a way that it directly contacts the contact surfaces 4 in a PV module 1 according to FIG. 1a.

FIG. 2a shows the PV module 1 of FIG. 1b together with a connection arrangement 10 according to the application before the step of mounting the connection arrangement 10 on the PV module 1. Figure 2b shows a detail from Figure 2a in the area of the left two connection contacts 5 of the PV module 1.

In FIGS. 3a and 3b, the PV module 1 with the connection arrangement 10 mounted on it is shown in the same way as in FIGS. 2a and 2b.

The connection arrangement 10 comprises four connection sockets 11 which are each plugged onto one of the connection contacts 5 . From the outer two of the connection boxes 11, a connection cable 12 leads away to the outside. This connection cable 12 is shown shortened in the figures. in a Settling this connection cable 12 is longer and has a connector at its end, with which a connection to an adjacent module or a module connection box o. Ä. can be made.

A connecting cable 13 is arranged between two junction boxes 11 and a diode element 14 is looped into it. The diode element 14 contains a bypass diode (not visible here) (cf. FIG. 4b), which makes contact with the two cable sections of the connecting cable 13 with its anode or cathode. In the present case, three bypass diodes are each connected antiparallel to each of the three cell arrangements of the PV module 1 .

The connection arrangement 10 can preferably be prefabricated and preassembled, so that it only needs to be placed on the connection contacts 5 during the final assembly of the PV module 1 . In this case, an adhesive sealant is preferably used, with which the junction boxes 11 are glued to the rear side 3 of the PV module 1 in a sealing manner.

FIG. 4a shows the detail of the rear side 3 of the PV module 1 with the connection arrangement 10 fitted, again in a top view. Two section lines are indicated in FIG. 4a, the corresponding sections being reproduced in FIGS. 4b and 4c.

FIG. 4b shows a longitudinal section through the part of the connection arrangement 10 shown in FIG. 4a along the connecting cable 12 and the connecting cable 13. The section accordingly also runs longitudinally through the two connection boxes 11, the detailed structure of which is thus visible.

The connection boxes 11 have an upper part 111 through which the connection cable or the connection cable 13 leads. There is also a foot 112 with which the junction box 11 rests on the back 3 of the PV module 1 . An outer edge of this foot 112 is suitable as an adhesive and sealing surface for the junction box 11 .

Within the junction box 11, a contact element 113 is arranged, the z. B. contacted the connection contact 5 of the PV module 1 in the form of a tulip contact. Electrically connected to the contact element 113 and optionally formed integrally with this, is an insulation-piercing contact 114, the has a tip pointing upwards and penetrates the connecting cable 12 or the connecting cable 13 in a contact-forming manner.

By using the insulation-penetrating contact 114, an electrical connection to the connecting cable 12 or to the connecting cable 13 can be produced in a simple manner and in a space-saving manner inside the junction box 11. In addition, the connection cable 12 can be designed in one piece with the corresponding section of the connection cable 13 . The connecting cable 12 and this section of the connecting cable 13 are therefore a continuous piece of cable. The same applies to the two sections of the connecting cable 13 in the connection box 11 shown on the left in FIG. 4b. In alternative configurations, a connection between the connecting cable 12 or the connecting cable 13 and the contact element 113 can also be produced by a crimping, soldering or welding process with a cable end then stripped in each case.

In the embodiment shown, the junction box 11 can be designed in one piece, with the continuous connection cable 12 or connection cable 13 being inserted through the upper part 111 and then the combined contact element 113 with the insulation-penetrating contact 114 being inserted from below into the connection cable 12 or the connecting cable 13 is pushed in. The junction box 11 preassembled in this way can then be placed onto the connection contact 5 as a whole.

According to the application, the diode element 14 is looped into the connecting cable 13 . In the cross section of FIG. 4b it can be seen that the diode element 14 is a bypass diode 15 which contacts a cable section of the connecting cable 13 and which is integrated into the connecting cable 13 in a mechanically resilient and electrically insulated manner, for example by means of a casting compound. The bypass diode 15 or the diode element 14 thus represents little more than a slight thickening in the connecting cable 13. The bypass diode 15 can be contacted with the conductor of the connecting cable 13, for example, by means of a crimping or a soldering point.

FIG. 4c again shows a cross section through one of the junction boxes 11, with the penetration of the insulation-piercing contact 114 into the connecting cable 12 or the connecting cable 13 being clearly visible in this representation. Reference sign

1 photovoltaic module (PV module)

2 frames

3 back

4 contact surface

5 connection contact

10 Connection Arrangement

11 junction box

111 top

112 feet

113 contact element

114 insulation piercing contact

12 connection cables

13 connection cables

14 diode element

15 bypass diode

Claims

9

Claims Connection arrangement (10) for a photovoltaic module (1) which has at least one cell arrangement which can be contacted externally at at least two contacts, having at least two connection sockets (11), wherein inside the connection sockets (11) connection cables (12) with the Contacts of the photovoltaic module (1) can be connected, characterized in that between two of the junction boxes (1 1) runs a connecting cable (13) into which a bypass diode (15) is looped. Connection arrangement (10) according to claim 1, in which the connection boxes (11) each have a contact element (1 13) which can be connected to the contacts of the photovoltaic module (1). Connection arrangement (10) according to claim 2, wherein the contact element

(113) is a tulip contact. Connection arrangement (10) according to any one of claims 1 to 3, wherein the junction boxes (1 1) each have an insulation-penetrating contact

(1 14) for connection to the connecting cable (12) and/or the connecting cable (13). Connection arrangement (10) according to any one of claims 1 to 4, wherein the connection cable (12) and a portion of the connecting cable (13) are formed by a cable that runs through one of the junction boxes (1 1). Connection arrangement (10) according to one of Claims 1 to 5, in which two sections of two connection cables (13) are formed by a cable which runs through one of the connection boxes (11). Connection arrangement (10) according to one of Claims 1 to 6, having a plurality of connection boxes (1 1) which are connected to one another in a chain-like manner via connecting cables (13), the connection cables (12) being connected to two outer ones of the connection boxes (1 1 ) are connected. Connection arrangement (10) according to one of Claims 1 to 7, in which the bypass diodes (15) and adjacent cable ends of sections of the connecting cable (13) are encapsulated with a casting compound.

9. Photovoltaic module (1) with at least one connection arrangement (10) according to one of claims 1 to 8.