DE102011122126A1 - Solar module for solar system, has holding element whose central region exerts force towards photovoltaic layer, and assembly of cooling structure and heat insulating material is pressed against photovoltaic layer - Google Patents

Abstract

The solar module (1) has a holding element (11) formed from spring steel wire, which presses the assembly of cooling structure (8) and heat insulating material (10) to the photovoltaic layer (6), and comprises bent end portions (16) which are supported at the two opposite primary frame portions (3). The secondary frame sections (4) are extended towards the photovoltaic layer such that the central region (12) of holding element exerts a force towards photovoltaic layer, and the assembly of cooling structure and heat insulating material is pressed against photovoltaic layer.

Description

The present invention relates to a solar module with a frame-shaped support structure comprising four frame parts extending at right angles to each other, a carrier layer photovoltaic layer enclosed in the support structure, comprising a radiation-transparent protective pane and doped semiconductor material, a cooling structure underlying the photovoltaic layer, and a heat-insulating material comprising the cooling structure insulates, is covered, and at least one holding member which presses the arrangement of cooling structure and heat insulating material against the photovoltaic layer.

Solar systems are now an integral part of the energy supply. They have prevailed especially in the roofs of private houses, but also in use on large-scale hall roofs, not least because of government subsidies.

The solar modules used for such solar systems usually have a rectangular shape with dimensions of about 1 m × 1.65 m. According to the available roof surface, this is provided with a large number of these solar modules.

In addition to pure solar modules, which are covered with a photovoltaic layer, increasingly used are those having a cooling structure to dissipate the heat generated by the photovoltaic layer, thereby increasing the efficiency of the photovoltaic layer. At the same time, the dissipated heat can be used.

A requirement of such solar modules is that they have a low weight so as not to excessively increase the roof surface load. In addition, they must have a simple structure in order to keep the manufacturing costs of the modules low. Finally, the plate-shaped components of the solar module should be safely, but constructively held without much effort, in the frame structure of the module.

Examples of solar modules are from the DE 10 2008 027 342 A1 or the US 4,392,008 known. DE 10 2008 027 342 A1 shows a cross-sectional view of a solar module with transversely and longitudinally extending tubes for cooling solar cells. On the side of the solar cells, the module is protected with a cover layer of glass or plastic. On the back, the arrangement is covered by a plate. This layered structure is held in a frame of U-shaped profiles.

The US 4,392,008 describes a solar collector with a substantially rectangular relatively flat housing having a bottom wall which is inserted into a frame structure.

The present invention is based on the object of substantially meeting the above-stated requirements for such solar modules.

This object is achieved by a solar module with the features of claim 1. Preferred embodiments are specified in the dependent claims.

The solar module according to the invention is characterized in that the at least one retaining element is formed from a spring steel wire having at its two ends angled end portions, which are respectively held on the two opposite first frame parts, and which has at least one central region between the two angled ends extending from the one of the other two second frame members toward the other opposed second frame member and biased toward the photovoltaic layer such that the center region of the retaining member exerts a force toward the photovoltaic layer and the cooling structure and heat insulating material assembly faces pushes the photovoltaic layer. With such an arrangement it is ensured that the prestressed holding elements made of spring steel wire press the cooling structure over the heat insulation material and the carrier layer against the photovoltaic layer. It is achieved by a good contact of the cooling structure with the photovoltaic layer and thus a good heat transfer. The holding elements can be bent in a simple manner from a spring steel wire with a suitable wire diameter. In this case, the center region can be bent in such a form that it extends into the middle of the module in order there to exert a sufficient compressive force on the thermal insulation material, thereby pressing the thermal insulation material against the cooling structure and thus the cooling structure against the photovoltaic layer the cooling structure is in heat-conducting contact with the photovoltaic layer.

The pressing force exerted by the middle region of the retaining element of spring steel wire on the heat insulating material can be adjusted so that in the non-tensioned state of the retaining element, the two angled ends of the spring steel wire or a surface which is spanned by the two ends, at an angle to a surface, which is spanned by the middle region associated with the part of the spring steel wire.

To mount such a retaining element, only the two angled ends of the spring steel wire on the two opposite first frame parts in corresponding brackets, which may be formed by the profile of the frame parts themselves, are attached.

It may be advantageous that even a short section of the spring steel wire, which connects to the respective angled end, referred to as the base section, extends at an angle of 90 ° to the angled end and thus applies to the respective second frame part and there in corresponding brackets is held.

It has been found that the parts in the frame-shaped support structure are held securely by holding elements in the form of the specially bent spring steel wire under the operating conditions of the solar module, even if the solar module is subjected to large temperature fluctuations, which are between -30 ° C and +90 ° C can lie.

The holding elements of the spring steel wire can not only be easily jammed on the frame structure, resulting in a fast-to-install construction of the solar module, but they can be solved if necessary, again in a simple manner.

In order to achieve a good pressing force by the built-in solar module holding element, it is preferred that the spanned by the sections of the at least one central region of the spring steel wire plane relative to the plane spanned by the two angled ends of the spring steel wire plane in the relaxed state of the spring steel wire by an angle between 10 ° and 60 °, preferably between 20 ° and 45 °, and more preferably about 25 °, are pivoted against each other.

As already mentioned above, the spring steel wire can be bent so that between the end portions and the central region of the spring steel wire in each case a wire portion, referred to as a base portion is located, which is associated with the one of the second frame parts and held on this.

The central region of the spring steel wire may be bent from at least three wire sections, wherein the three wire sections preferably have a trapezoidal shape in the relaxed state of the spring steel wire. Due to this trapezoidal shape, the spring steel wire is applied over a large area of the heat insulating material to press this against the cooling structure and the cooling structure against the photovoltaic layer.

The end sections of the spring steel wire should include an angle of 90 ° to 135 ° with the spring steel wire of the base section in the relaxed state of the spring steel wire.

A further advantage can be achieved if, in the relaxed state of the holding element, the distance between the ends of the end sections is greater, preferably by 10% to 30%, than the distance between the two frame parts on which these end sections are held. As a result, the two end sections are then pressed against the frame parts, if they are held on the two opposing frame parts. By this pressure force, it may be sufficient that the end portions of the spring steel wire must be placed only under the frame parts, without attaching them in addition.

For the spring steel wire, a wire diameter of 3 to 6 mm has been found suitable, in particular if the solar module has a size in the range of 1 m × 1.65 m, and in particular if two of these holding elements are used.

The at least one central region of the spring steel wire or retaining element should extend to approximately the middle of the support structure between the two frame parts.

For large-sized solar modules, the support member should have two center portions extending from the respective frame member from which these center portions of the support member extend to the center of the heat insulation layer.

Preference is given to two holding elements for a solar module, wherein the one holding element is assigned to a first frame part and the other holding element is associated with the opposite first frame part.

Further details and features of the invention will become apparent from the following description of an embodiment with reference to the drawings. In the drawing shows

1 1 is a schematic view of the rear side of a solar module according to the invention with two holding elements,

2 a partial cross section through the solar module of 1 along the long frame part in the area of the corner,

3A a single retaining element, as in the solar module of 1 is used, in a plan view,

3B the retaining element of 3A in a perspective view in the relaxed state,

3C a section along the section line AA of 3A , and

3D an enlarged detail view of the section B in 3C ,

The solar module as it is in 1 and in the partial cross section of 2 is shown, generally with the reference numeral 1 is designated, has a rectangular shape in plan view, through a frame structure 2 is predetermined. The frame structure 2 is made of four orthogonal to each other first frame parts 3 and two second longer frame parts 4 composed.

Like the cross section of the 2 shows, have the frame parts 3 and 4 , which are formed as profiles, at its upper end a groove 5 into which a photovoltaic layer 6 is inserted. The photovoltaic layer 6 is on the outside by a radiation-transparent protective screen 7 covered.

At the bottom of the photovoltaic layer 6 or the carrier layer is a cooling structure 8th which may, for example, be a heat exchanger structure through which a cooling medium flows. The remaining space 9 the frame structure 2 is by heat insulation material 10 , For example, in the form of a plate filled.

The thermal insulation material 10 is in the frame structure 2 by holding elements 11 held in the form of spring steel wires, whose arrangement on the frame structure 2 based on 1 is apparent.

The shape of the bent spring steel wire of such a holding element 11 is more detailed on the basis of 3A to 3D seen.

The holding element 11 has a center area 12 which is made up of two basic sections 13 and one between these base sections 13 lying trapezoidal section 14 composed. To the two base sections 13 of the middle section 12 close, at an angle, with the reference numeral 15 denotes, from 90 °, angled end portions 16 at.

As based on the 3B and 3C is apparent, is the trapezoidal section 14 of the middle section 12 opposite the end sections 16 twisted the spring steel wire. This twist can be characterized by the trapezoidal section 14 spanned level opposite to the two angled end sections 16 the spring steel wire plane spanned in the relaxed state of the spring steel wire, as in the 3A to 3C is at an angle between 10 ° and 60 °, preferably between 20 ° and 45 °, and more preferably of about 25 °, pivoted against each other or rotated.

This angle is in 3C with the reference number 17 designated.

The spring steel wire of the holding element 11 has a diameter 18 in the range of 3 to 6 mm (see 3D ).

Two of the retaining elements 11 like the one in the 3A and 3B are shown in the solar module 1 used that in 1 is shown. In each case a holding element 11 is the two frame parts 4 (the long frame parts of the frame structure 2 ). Alternatively, two retaining elements 11 the two frame parts 3 (The short frame parts of the frame structure 2 ) or it may be in the solar module 1 four of the retaining elements 11 be used, the two frame parts 3 and the two frame parts 4 one holding element each 11 assigned.

In the relaxed state of the retaining element 11 own the two end sections 16 a distance from each other that is greater than the length of the frame parts 4 or the distance of the shorter frame parts 3 from each other.

After the solar module 1 is composed with the structure described above and the heat insulating material 10 in the frame structure 2 is inserted, the respective holding element 11 in the frame structure 2 used. For this purpose, the holding element 11 with the trapezoidal section 14 on the thermal insulation layer 10 hung up and the two base sections 13 , which are on both sides of the trapezoidal section 14 connect, be in the profile of the long frame part 4 inserted; during this process are simultaneously the two end sections 16 be moved towards each other to reduce the distance, so that the two end portions 16 between the two frame parts 3 fit. Such a compression is possible in a simple manner that the trapezoidal section 14 of the middle section 12 yields by slight deformation. The two end sections 16 , which then due to the angled course to the surface of the heat insulating material 10 (Angle 17 in 3C ) from the surface of the heat insulating material 10 stand down, be down on the surface of the thermal insulation material 10 pressed and in each case in the profile of the corresponding first frame part 3 as indicated by the 2 is apparent. This process is supported by the fact that the previously compressed trapezoidal section 14 relaxed again and thus on the basic sections 13 a pressure on the end sections 16 exerts; This will become the end sections 16 safe in the profile of the frame parts 3 held.

The same process is done with the retaining element 11 repeated, the opposite frame part 4 assigned.

If both retaining elements 11 in the frame structure 2 are inserted, press the two trapezoidal sections 14 on the central area of the thermal insulation material 10 , which thereby large-scale to the cooling structure 8th and these in turn to the photovoltaic layer 6 is pressed.

If the pressing force, over the holding elements 11 on the thermal insulation material 10 is exercised, is not sufficient or needs to be changed, the trapezoidal sections 14 be formed so that they are even further to the middle of the frame structure 2 extend than this in 1 is shown. Also, the middle range 12 be bent in a different form than the illustrated trapezoidal shape. Furthermore, it is possible between the two angled end sections 16 to provide two or more areas that the trapezoidal section 14 or a similar form. Also, the pressing force can be increased by the fact that the two end portions at a larger angle 17 to the through the middle area 12 spanned plane as shown in the figures.

Based on 2 it can be seen that between the heat insulation material 10 and the holding element 11 a thin protective strip 19 in the area of the profile of the frame parts 3 . 4 is used, for example, a bar made of plastic or aluminum, to the pressure, in particular through the end portions 16 the holding elements 11 is exerted flat on the heat insulating material 10 to distribute and to prevent the bar profile of the holding element 11 in the thermal insulation material 10 presses.

Furthermore, the 2 to see that between cooling structure 8th and photovoltaic layer 6 a first metal foil 20 and a second metal foil 21 that still have the tubes of the cooling structure 8th covering on the opposite side, is interposed. Also is between thermal insulation material 10 and the cooling structure 8th or the second metal foil 21 a balancing mat 22 made of a resilient material, such as a felt mat, inserted to thereby the second metal foil 21 on the one hand to the tubes of the cooling structure 8th and second, in the spaces between the tubes of the cooling structure 8th to the first metal foil 20 to press. This will change the heat transfer between photovoltaic layer 6 and cooling structure 8th significantly improved.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102008027342 A1 [0006]
• US 4392008 [0006, 0007]

Claims (10)

Solar module ( 1 ) with a frame-shaped carrying structure ( 2 ; 3 . 4 ), the four frame parts extending at right angles to each other ( 3 . 4 ), one in the support structure ( 2 ; 3 . 4 ), made of radiation-transparent protective screen ( 7 ) and doped semiconductor material existing photovoltaic layer ( 6 ) with carrier layer, one the photovoltaic layer ( 6 ) underlying cooling structure ( 8th ) provided with a thermal insulation material ( 10 ), the cooling structure ( 8th ) insulates, is covered, and at least one retaining element ( 11 ) comprising the arrangement of cooling structure ( 8th ) and thermal insulation material ( 10 ) against the photovoltaic layer ( 6 ), characterized in that the at least one retaining element ( 11 ) is formed from a spring steel wire, the angled end portions at its two ends ( 16 ), which in each case at the two opposite first frame parts ( 3 ), and between the two angled ends ( 16 ) at least one central area ( 12 ) extending from one of the other two, second frame parts ( 4 ) in the direction of the other, opposite second frame part ( 4 ) and in the direction of the photovoltaic layer ( 6 ) is biased so that the middle region ( 12 ) of the retaining element ( 11 ) a force in the direction of the photovoltaic layer ( 6 ) and the arrangement of cooling structure ( 8th ) and thermal insulation material ( 10 ) against the pholovoltaic layer ( 6 ) presses. Solar module according to claim 1, characterized in that through the sections of the at least one central region ( 14 ) of the retaining element ( 11 ) spanned plane relative to the through the two angled ends of the retaining element ( 11 ) in the relaxed state of the retaining element ( 11 ) are pivoted relative to each other at an angle between 10 ° and 60 °, preferably between 20 ° and 45 °, and more preferably about 25 °. Solar module according to claim 1 or 2, characterized in that between the end sections ( 16 ) and the middle area ( 12 ) of the retaining element ( 11 ) each a wire section, as the base section ( 13 ), which is the one of the second frame parts ( 4 ) and is held on this. Solar module according to one of claims 1 to 3, characterized in that the central region ( 12 ) is bent from at least three wire sections, wherein the three wire sections in the relaxed state of the retaining element ( 11 ) have a trapezoidal shape. Solar module according to claim 3 or 4, characterized in that the end sections ( 16 ) in the relaxed state of the retaining element ( 11 ) with the base section ( 13 ) enclose an angle of 90 ° to 135 °. Solar module according to one of claims 1 to 5, characterized in that in the relaxed state of the retaining element ( 11 ) the distance between the end sections ( 16 ) is greater, preferably by 10% to 30%, than the distance between the two frame parts ( 3 ), at which these end sections ( 16 ) are held. Solar module according to one of claims 1 to 6, characterized in that the spring steel wire of the retaining element ( 11 ) a diameter ( 18 ) of 3 to 6 mm. Solar module according to one of claims 1 to 7, characterized in that the at least one central region ( 12 ) to about the middle of the frame structure ( 2 ) between the two frame parts ( 4 ). Solar module according to one of claims 1 to 8, characterized in that the at least one retaining element ( 11 ) two middle areas ( 12 ) having. Solar module according to one of claims 1 to 9, characterized in that two holding elements ( 11 ) are provided, wherein the one retaining element ( 11 ) a frame part ( 4 ) and the other retaining element ( 11 ) the opposite frame part ( 4 ) assigned.

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