WO2008148524A2

WO2008148524A2 - Solar module with an electrical connector element

Info

Publication number: WO2008148524A2
Application number: PCT/EP2008/004422
Authority: WO
Inventors: Heinz Scherer; Andreas Woeber; Guenter Arens; Markus Muench
Original assignee: Tyco Electronics Amp Gmbh
Priority date: 2007-06-04
Filing date: 2008-06-03
Publication date: 2008-12-11
Also published as: WO2008148524A3

Abstract

A solar module (1) for producing electrical power comprises a layered arrangement (2), with a mutually spaced sheet-like first and second layer (21, 22), and at least one solar cell (25) for producing electrical power from irradiated radiation, which is arranged between the layers (21, 22). The first layer (21) forms a first cross-sectional area (21A) in a first cross-sectional -plane (100) of the layered arrangement (2). An electrical connection system (3) serves to electrically interconnect the solar cell (25), and has a connector element (4, 4-1, 4-2, 4-3), which is connected to the layered arrangement (2) in a lateral edge region (26) thereof and, in a plan view onto the layered arrangement (2), is arranged in a second cross-sectional plane (200) of the layered arrangement (2) inside the borders of the first cross-sectional area (21A). A connection system that is reliably protected from external influences is thus obtained.

Description

SOLAR MODULE WITH AN ELECTRICAL CONNECTOR ELEMENT

The present invention relates to a solar module for producing electrical power with a layered arrangement comprising a mutually spaced sheet-like first and second layer and at least one solar cell for producing electrical power from radiation, which is arranged between the layers. Furthermore, an electrical connection system having a connector element is provided for the electrical interconnection of the solar cell.

This type of solar module typically comprises a layered arrangement, for example in the form of a front and a back glass cover with low absorption, the individual solar cells, which contribute to the production of electrical power through a photovoltaic effect, being arranged between these glass covers. The solar cells are typically interconnected inside the layered arrangement by copper bands. In addition, the solar panel thus formed is provided with a frame made of aluminium, stainless steel or plastic material. Solar modules of this type are usually assembled to form solar module arrays by connecting them mechanically and electrically, the electrical connection systems of the different solar modules being connected to each other by corresponding electrical connector elements in order to electrically connect their respective solar cells.

A solar module of the type described in the introduction is known in particular from EP 0 798 787 A2. A photovoltaic plate-shaped solar module, in particular for use as a facade element or roof element with an outer pane facing the incident light, has at least one inner plate arranged at a distance behind it in the direction of light incidence to produce an intermediate space and a peripheral construction surrounding the outer „

pane and the inner plate and connecting them tightly together. Inside the solar module, the connecting lines for electric connection to other adjacent solar modules are guided into the region of the periphery, connecting lines being attached to a lug that projects into the intermediate space, being embedded in the cast resin or the compound foils, and being guided out of the plate construction. The lug is connected to an insulating bushing extending outside of the plate construction, the connector elements of the lug each being connected to one of the connecting lines laid through the insulating bushing and to corresponding connector ele- ments of adjacent solar modules. The insulating bushing rests outside of the plate construction on the edge thereof, the connection lug being rigidly connected to the hollow cylindrical insulating bushing.

An advantage of such a solar module is that construction personnel can also install solar technology systems by simply joining modules using the connector elements at the end of the insulating bushings. A disadvantage, however, is that the insulating bushing is exposed and fixed rigidly in the lateral edge region of the solar module, so that only limited flexibility and reliability can be achieved when arranging and interconnecting a plurality of solar modules. The exposed fixing of the in- sulating bushing can in particular lead to damage to the insulating bushing due to external influences.

An object of the present invention is to provide a solar module of the type described in the introduction, the electrical connection system of which can be fixed comparatively quickly to the solar module with a high degree of reliability.

This object is achieved through a solar module of the type described in the introduction according to the features of claim 1.

In the case of a solar module of the type mentioned in the introduction, it is provided according to the invention that the electrical con- nection system for the electrical interconnection of the at least one solar cell of the solar module has a connector element that is configured in a special form and is arranged on the solar module. In particular, the connector element is connected to the layered arrangement of the solar module in a lateral edge region thereof. In particular, the connector element rests on the edge of one of the layers of the layered construction. The first layer of the layered arrangement of the solar module forms a first cross-sectional area in a first cross-sectional plane of the layered arrangement. On the other hand, the connector element is arranged in a second cross-sectional plane of the layered arrangement inside the borders of the first cross-sectional area, formed by the first layer in a plan view onto the layered arrangement. An advantage of this arrangement of a solar module is in particular, that the connector element can be integrated into the envelope of the layered arrangement, so that the connect- or element substantially does not project from the layered arrangement of the solar module, so that the connector element is integrated so to speak into the layered arrangement. Another advantage of the invention is that this type of solar module does not have to be provided with a socket, which contributes to comparatively high production and as- sembly costs. On the other hand, the invention allows the electrical connection of the solar module and its cabling to be achieved without subsequent fitting of a socket. In order to achieve this, the connector element is integrated into the layered arrangement during the laminating process during production, accomplishing a considerable time saving in the manufacture of a solar module. The connector element can be soldered to the electrical connection system of the solar module at the same stage in production as the soldering of the solar cell in the layered arrangement. Moreover, this results in a compact, protected construction of a solar module, the connector element being protected from external influences, especially during the transportation of the solar module, because it is arranged inside the cross-sectional area of the first layer, for ex- ample, a front glass cover. Thus, an overall high reliability of the electrical connector system is achieved, because damage to the rigidly fixed connector element can effectively be avoided. This is advantageous in particular over arrangements with externally mounted sockets, and over the arrangement of a photovoltaic solar module according to the docu- ment EP 0 798 787 A2 mentioned in the introduction. An externally fixed socket of a solar module, and also the exposed insulation bushing, which is connected to the plate construction via a connecting lug and extends outside the plate construction, have the disadvantage that both forms of connector element clearly project from a group of solar panels and accordingly only allow external cabling. On the other hand, concealed cabling of a solar module is made possible according to the invention, so that enhanced design aspects can be taken into account in the arrangement of solar modules.

In particular, the connector element according to the present in- vention is arranged in such a way that it is concealed by the first layer of the layered arrangement in the plan view onto the solar module. This allows a completely protected construction and a concealed cabling of the connector element.

According to another embodiment of the invention, the at least one solar cell and the connector element are arranged together in a second cross-sectional plane of the layered arrangement, and the second iayer of the layered arrangement in a third cross-sectional plane forming a third cross-sectional area. The connector element is arranged _

outside the borders of the third cross-sectional area in the plan view onto the layered arrangement in the process.

In particular, a first lateral face of the connector element is placed onto the second layer and a second lateral face, which is arranged ap- proximately at right angles to the first lateral face, abuts the first layer. This is advantageous in particular if the first and second layer are mutually offset in tiers. In this case, the connector element according to an embodiment of the invention is arranged in the tiered offset of the first and second layer, resulting in a compact, protected construction of the solar module.

The first layer forms a front layer of the solar module, for example, which is turned towards the incident radiation. In particular, the first and second layers each have different cross-sectional areas, the cross-sectional area of the first layer being larger than the cross-sectional area of the second layer. The solar module is thus constructed so that the first layer, for example the front glass of the solar module, is larger than the second layer, for example the back glass cover of the solar module, so that the connector element and its cabling are concealed behind the front glass cover. A particularly protected construction then arises in par- ticular if the outer limit of the solar module is formed by the first layer, for example the front cover of the solar module, in a plan view onto the solar module. There is also an advantage from a design point of view in that when the solar module is assembled, only the front cover is visible so that with an arrangement of a plurality of solar modules, a uniform glass face is achieved, which is turned to the incident light.

According to an embodiment of the invention, as well as this connector element, it is also possible to provide the electrical connection system with further connector elements for, which are connected to the layered arrangement in at least one lateral edge region thereof. The fur- _„

ther connector elements are also arranged within the borders of the first cross-sectional area of the first layer in the plan view onto the layered arrangement.

According to an embodiment of the invention, the connector ele- ment can be an electrical connector element for the external electrical connection of the solar module. With this type of connector element, an electrical connection region is constructed in such a way that an electrical line for the external electrical connection of the solar module is provided in this connection region or can be connected to it. In order to achieve concealed cabling, the electrical line is arranged inside the borders of the first cross-sectional area in the plan view onto the layered arrangement.

The connector element can also contain at least one diode, which conducts a current past at least one solar cell of the solar module, if this solar cell is not contributing, or contributing only to a limited extent, to the production of electrical power. These diodes, known as bypass diodes, can be provided in varying numbers also for large solar panels in one or more connector elements, which are connected to a panel. Bypass diodes are needed so that the solar module can continue to work at reduced capacity or can be bypassed in the case of partial shade or partial defect. The bypass diode is connected in parallel with individual solar cells or a specific arrangement of solar cells and conducts the current produced past solar cells that are not working.

The following advantages in particular can be achieved with a sol- ar module according to the invention: a connector element of the solar module according to the invention can be pre-fabricated in one or more defined configurations and connected to the layered arrangement according to the requirements during the production of the solar module. This allows a flexible and protected placement onto a lateral face of the module or layered arrangement, so that overall a tight package of a plurality of solar modules into a solar module array and a compact protected construction with the placement and configuration of the connector element according to the invention can be created. Furthermore, a modular extendibility to a plurality of connector elements exists in the case of such a connection system, so that appropriately formed or a corresponding number of connector elements can be used according to the requirements and the size of the solar panel. This allows different interconnections of a plurality of solar modules, for example connection in series and/or parallel of a plurality of solar cells or modules, to be achieved with a uniform connection system that is protected from external influences. The invention can advantageously be used in particular in the photovoltaic industry, glass facade industry, when using panels known as thin-layer panels and in the case of panels that are exposed to ex- treme environmental conditions.

Further advantageous embodiments and developments of the invention are described in the sub-claims.

The invention is described in more detail with reference to the figures in the drawings, which show various embodiments of a solar mod- ule according to the invention, and in which:

Figure 1 is a cross-section of a solar module according to the invention in a frontal plan view onto the layered arrangement with a first embodiment of a connector element,

Figure 2 is a lateral section of a solar module according to Fig- ure 1,

Figure 3 is a cross section of a solar module according to the invention in a frontal plan view onto the layered arrangement with another embodiment of connector elements, _n

Figure 4 is a lateral section of a solar module according to Figure 3.

Figures 1 and 2 are cross-sections of a first embodiment of a solar module 1 according to the invention in a frontal plan view onto the layered arrangement 2 (Figure 1) and in a lateral section (Figure 2) with a first embodiment of a connector element 4. As can be seen in particular from Figure 2, the solar module 1 comprises a layered arrangement 2, which in turn comprises a plurality of layers. In the present embodiment, a sheet-like first layer 21 in the form of a glass plate forms a front glass cover with low absorption, which serves to protect the components arranged behind it in the direction of light incidence. A second sheet-like layer 22 is likewise constructed in the form of a glass plate and forms a rear inner plate of the solar module 1, the layer 22 being arranged at a distance from the first layer 21, forming a space there between. In the space between the layers 21 and 22 are arranged one or more solar cells 25, which in turn are contacted on the interior by a foil 24, for example a copper foil.

The solar cells 25, together with the foil 24, are embedded on both sides in embedding material 23, which is in the form of a gel-like foil, for example. The embedding material 23 sticks the layered construction when it is melted during production of the layered arrangement 2. A compact layered group substantially without air bubbles is thus formed, because the embedding material 23 can penetrate gaps and cracks in the layered arrangement 2 during production. The space remaining between the first layer 21 and the second layer 22 is thus substantially filled with the embedding material 23. Instead of glass plates, a flexible, for example foil-like, transparent material can also be used for the layered arrangement 2, so it can be adapted to three-dimensionally shaped surfaces for example, on which the solar modules are to be arranged. As can be seen in particular with reference to Figure 1, the individual solar cells 25 are connected in series via an electrical connection system 3, the beginning and end of the series connection of the solar cells 25 being contacted by contact elements 5-1 and 5-2 respectively. s The electrical connection system 3 further comprises e connector element 4, which is used in this embodiment for the external electrical connection of the solar module 1, in particular to produce an electrical con- Tiection of -the τsotar module T to at least one external electrical device, such as a consumer, or to connect another solar module 1. The connect-o or element 4 is connected to the layered arrangement 2 in a lateral edge region 26 (Figure 2) thereof via the contact elements 5-1 and 5-2, which project into the layered arrangement 2. A first lateral face 27 (Figure 2) of the connector element 4 is placed onto the second layer 22 and a second lateral face 28, which is arranged approximately at right angles to the lat- eral face 27, abuts the first layer 21. The first layer 21 and the second layer 22 are mutually offset in tiers, the connector element 4 being arranged in the tiered offset forming the edge region 26. The connector element 4 is thus fixed to an upper edge of the second layer 22, resting on one of the edges of the layer 22, the contact elements 5-1 and 5-2, in particular in the form of respective connection lugs, projecting into the interior of the layered arrangement 2. After production the layered arrangement 2 and the contact element 5 are mutually arranged in such a way that the foil 24 is contacted by the contact elements 5-1 and 5-2.

Referring to Figure 2, the first layer 21 forms a first cross-sectional area 21A in a first cross-sectional plane 100 of the layered arrangement 2. This is substantially rectangular, as can be seen from Figure 1 in the frontal plan view. On the other hand, the solar cells 25 and the connector element 4 are arranged in a second cross-sectional plane 200 behind the first layer 21 in the direction of incidence of the light. Referring in particu- lar to Figure 1, the connector element 4 and the solar cells 25 are arranged inside the borders 21 B of the cross sectional area 21 A of the first layer 21. Figure 1 shows that the connector element 4 is concealed by the first layer 21 in a plan view onto the solar module 1 or onto the 5 layered arrangement 2. In particular Figure 1 and also Figure 3 are plan views perpendicular to the cross-sectional plane 100 of the layered arrangement 2, and consequently perpendicular to the frontal main face of the first layer 21.

On the other hand, the second layer 22 is arranged in a thirdo cross-sectional plane 300 of the layered arrangement 2, as shown in Figure 2, and forms a cross-sectional area 22A in this cross-sectional plane 300. This cross-sectional area 22A is arranged parallel to the cross-sectional area 21 A of the first layer 21, the solar cells 25 being arranged parallel thereto in the space formed there between. Only the side view ins Figure 2 shows that the connector element 4 is arranged outside the edges of the cross-sectional area 22A. In particular the connector element 4 is placed, in a rear plan view onto the solar module 1, on the upper limit of the cross-sectional area 22A, consequently on the second layer 22 itself. Overall the layers 21 and 22 therefore have different cross-o sectional areas 21 A and 22A, the cross-sectional area 21 A of the layer 21 being larger than the cross-sectional area 22A of the second layer 22. As can be seen with reference to Figure 1, the first layer 21 forms the outer edge of the solar module 1 with its boarders 21 B, so that the connector element 4 is protected from external mechanical influences by the first5 layer 21.

As also shown in Figure 1, two electrical connection regions 42 are provided in the case of the connector element 4, to which respective cables 11 and 12 are connected. In this respect the cables 11 and 12 can be moulded directly onto the connector element 4 or can be connected via respective contact elements 5 to the connection regions 42. The electrical cables 11 and 12 are likewise arranged inside the borders 21 B of the cross-sectional area 21 A in the plan view onto the layered arrangement 2 in accordance with Figure 1, so that concealed cabling is advant- ageously achieved. Only the first layer 21 is visible from outside, so that a substantially uniform glass face can be achieved in the case of larger solar panel arrangements.

As also shown in Figure 1, a diode 6 is contained in the connector element 4 and, as a bypass diode 6, conducts a current past the group of solar cells 25 of the solar module 1, if one or more solar cells 25 are not contributing, only contributing only to a limited extent, to the production of electrical power. The diode 6 is connected between the projecting contact elements 5-1 and 5-2 in this embodiment.

Figure 3 is a cross-section of a solar module 1 according to the in- vention in a frontal plan view onto the layered arrangement 2, a plurality of connector elements 4-1 to 4-3 being used according to this embodiment, some of which are configured differently. In this respect Figure 4 is a lateral section of the solar module 1 according to Figure 3. The embodiment of the solar module 1 according to Figures 3 and 4 basically cor- responds to the embodiment according to Figures 1 and 2 already described, so it will not be described in more detail again here.

Unlike the solar module 1 according to Figures 1 and 2, the solar module 1 according to Figures 3 and 4 has a plurality of connector elements 4-1 to 4-3, which are each connected to the layered arrangement 2 in the same lateral edge region 26 thereof. Similarly to the connector element 4 according to Figures 1 and 2, the connector elements 4-1 to 4- 3 in the plan view of Figure 3 are also arranged inside the borders 21 B of the cross-sectional area 21 A. Also with regard to the remainder of the arrangement with respect to the layered arrangement 2, the connector ele- ments 4-1 to 4-3 are arranged similarly to the connector element 4 according to Figures 1 and 2, as shown in particular with reference to Figure 4 in the example of the connector element 4-1.

The connector elements 4-1 to 4-3 do, however, differ in part from the connector element 4 according to Figures 1 and 2. The connector elements 4-1 to 4-3 have the function of electrically connecting the solar module 1 externally, the cable 11 being connected in the connection region 42 of the connector element 4-1, while the cable 12 is connected to the connection region 42 of the connector element 4-3. The individual solar cells 25 are connected in series via the electrical connection system 3, the connection in series of the solar cells 25 being contacted at individual points on the contact elements 5-1 to 5-n, unlike the previous embodiment. The connector elements 4-1 to 4-3 are each connected to two projecting contact elements 5. Unlike the connector elements 4-1 to 4-3, the connector element 4-2 does not serve to electrically connect the solar module 1 externally, and therefore does not have any cable 11 connected to it. The connector element 4-2 serves primarily to accommodate a bypass diode 6, which is connected to the electrical connection system 3 of the layered arrangement 2 via flexibly constructed lines 61 and 62 respectively. The flexible lines 61 and 62 are constructed from what is known as flexible punched grid, for example, and have the function of compensating coefficients of expansion of different material, should the different components in the layered arrangement 2 expand to different extents due to the different coefficients of expansion at different temperatures. A bypass diode 6 is likewise provided in the connector elements 4-1 to 4-3. Overall the bypass diodes 6 have the function of conducting a current past the associated group of solar cells 25 of the solar module 1 if one or more solar cells 25 of a respective group are not contributing, or contributing only to a limited extent, to the production of electrical power. The module can thus continue to work in partial shade and at correspondingly reduced capacity. The diodes 6 are each connected between the projecting contact elements 5-1 to 5-n as shown in Figure 3. The arrangement of a solar module 1 shown in Figures 3 and 4 allows a solar panel in the form of the layered arrangement 2 to be connected in a simple and flexible manner via a connection system, for example to a further solar module 1. According to the size and type of solar panel, a different number of connector elements 4, which also in particu- lar each contain a number of bypass diodes 6, can be provided in the layered arrangement 2. This technology can therefore also be employed in the case of large solar panels, by using a suitable number of connector elements 4. A connection system of this type is therefore highly flexible, and besides this the compact and protected construction means that the connector elements 4 are protected from external mechanical influences.

Claims

1. Solar module for producing electrical power having a layered arrangement (2) comprising a mutually spaced sheet-like first and second layer (21, 22), at least one solar cell (25) for producing electrical power from radiation, which is arranged between the layers (21, 22), wherein the first layer (21) forms a first cross-sectional area (21A) in a first cross- sectional plane (100) of the layered arrangement, and an electrical connection system (3) for the electrical interconnection of the solar cell (25), characterized in that the electrical connection system (3) has a connector element (4, 4-

1, 4-2, 4-3), which is connected to the layered arrangement (2) in a lateral edge region (26) thereof and, in a plan view onto the layered arrangement, is arranged in a second cross-sectional plane (200) of the layered arrangement inside the borders of the first cross-sectional area (21 A).

2. Solar module according to claim 1, wherein the connector element (4, 4-1, 4-2, 4-3) is arranged in such a way that it is concealed by the first layer (21) in the plan view onto the layered arrangement.

3. Solar module according to either claim 1 or claim 2, wherein the at least one solar cell (25) and the connector element (4, 4-1, 4-2, 4-3) are arranged in a second cross-sectional plane (200) of the layered arrangement.

4. Solar module according to any one of claims 1 to 3, wherein the second layer (22) forms a third cross-sectional area (22A) in a third cross- sectional plane (300) of the layered arrangement, the connector element (4, 4-1, 4-2, 4-3) being arranged outside the borders of the third cross- sectional area (22A) in the plan view onto the layered arrangement.

5. Solar module according to any one of claims 1 to 4, wherein the first layer (21) forms a front layer of the solar module (1), which is turned towards the incident radiation.

6. Solar module according to any one of claims 1 to 5, wherein the first and second layer (21, 22) have different cross-sectional areas (21 A, 22A), the cross-sectional area (21A) of the first layer (21) being larger than the cross-sectional area (22A) of the second layer (22).

7. Solar module according to any one of claims 1 to 6, wherein the outer limit of the solar module (1) is formed by the first layer (21) in the plan view onto the layered arrangement.

8. Solar module according to any one of claims 1 to 7, wherein a first lateral face (27) of the connector element (4, 4-1, 4-2, 4-3) is placed onto the second layer (22) and a second lateral face (28), which is arranged approximately at right angles to the first lateral face abuts the first layer (21).

9. Solar module according to any one of claims 1 to 8, wherein the first and second layer (21, 22) are mutually offset in tiers, the connector ele- ment (4, 4-1, 4-2, 4-3) being arranged in the tiered offset.

10. Solar module according to any one of claims 1 to 9, wherein the electrical connection system (3) has further connector elements (4-2, 4-3) as well as the connector element (4-1), which are connected to the layered arrangement (2) in at least one lateral edge region (26) thereof and are arranged within the borders of the first cross-sectional area (21 A) in the plan view onto the layered arrangement.

11. Solar module according to any one of claims 1 to 10, wherein an electrical connection region (42) of the connector element (4, 4-1, 4-2, 4- 3) is constructed such that an electrical cable (11, 12) for the external electrical connection of the solar module (1) is provided in this connection region (42) or can be connected to it, the electrical cable (11 , 12) being arranged inside the borders of the first cross-sectional area (21A) in the plan view onto the layered arrangement.

12. Solar module according to any one of claims 1 to 11, wherein at least one diode (6) is contained in the connector element (4, 4-1, 4-2, 4-3) and conducts a current past at least one solar cell (25) of the solar module (1), if it is not contributing, or contributing only to a limited extent, to the production of electrical power.

13. Solar module according to claim 12, wherein the diode (6) is connected to the electrical connection system of the layered arrangement via a flexibly configured ^"line (61 , 62).

14. Solar module according to any one of claims 1 to 13, wherein - a plurality of contact elements (5-1, 5-n) which project into the layered arrangement (2) and are guided from the layered arrangement (2) are provided, the connector element (4) is connected to at least two contact elements (5-1 , 5-2) which are guided outwards.