WO2012041475A2

WO2012041475A2 - Support construction for solar modules

Info

Publication number: WO2012041475A2
Application number: PCT/EP2011/004805
Authority: WO
Inventors: Andreas Ell; Ilona Ell
Original assignee: Andreas Ell; Ilona Ell
Priority date: 2010-09-30
Filing date: 2011-09-26
Publication date: 2012-04-05
Also published as: WO2012041475A3; DE102010047151B3

Abstract

The invention relates to a support construction (1) for stand-mounted photovoltaic modules (5) which can be installed, for example, on a flat roof or a pitched roof. The invention allows azimuthal tracking by the PV modules (5). For this purpose, the support construction (1) comprises a tracking unit (3) having a scissors-type frame (9) which can itself move by means of a slotted guide (7). An optionally movable suspension arrangement for the PV module stands (4) also makes it possible for the angle of elevation to be tracked.

Description

Supporting structure for solar modules

The invention relates to a support structure for photovoltaic modules (PV modules). The yield of a PV module essentially depends on the angle of solar radiation. It is true that in vertical sunlight, the yield of the PV module is greatest and decreases with increasing angle. One problem is that the suns migrate in the course of a day and the angle of incidence changes constantly when the PV module is stationary. The angle of incidence is therefore rarely optimal.

In order to obtain the greatest possible yield, it is therefore expedient to move the PV module so that it follows the course of the sun, so that the irradiation takes place as long as possible as vertically as possible. For individual PV modules, this is relatively easy, in which the module is placed on a turntable that can perform a circular motion. However, this is difficult for systems with multiple modules, because the turntable would have to be very large or for each module a turntable would have to be present. In both cases, the mechanical complexity is very large, so that such systems are very expensive. Solar systems for power generation are now widely used in private households, the modules are usually arranged on the roof of a house. For private purposes, the above turntable arrangement is completely unsuitable.

CONFIRMATION COPY On flat roofs or low pitched or pitched roofs mainly supporting structures are used, in which the PV modules are arranged on stands that have a geographic location adapted elevation angle. In these stands, it is relatively easy to make the elevation angle of the stand variable, so that at least the elevation angle can be adapted to the changed position of the sun. This can also be done automatically. Although the yield can be increased thereby, a greater gain in yield would be possible by an azimuthal tracking, since the azimuth angle, which the sun passes over during the day, is greater than the migrated elevation angle.

An optimal solar system therefore leads both angles. However, this is currently not economically feasible in an investment for private purposes.

The object of the invention is therefore to provide a support structure for a photovoltaic system, which is suitable for private purposes and allows improved energy yield.

This object is achieved in that the holder has at least two fixed, circular arc-shaped guide rails, which are aligned parallel to the mounting plane, wherein the curvature of at least one guide rail against the curvature of the other guide rail is aligned, that the tracking unit has a self-supporting frame which is guided in the guide rails, wherein the frame is deformable parallelogram, whereby the azimuth angle of the stator is variable and that the stator is fixed to the frame.

By changing the azimuth angle of the PV modules, the Daily course of the sun are followed at least in a partial area, whereby the duration of the vertical as possible vertical radiation is extended. This automatically increases the yield of the PV module.

The azimuthal tracking is made possible by a scissor-type construction of the frame. For this purpose, the frame has several points which are movably guided in the circular guide rails. By moving along the guide rails, the frame is deformed in a parallelogram shape.

Preferably, at least one guide rail has a motor drive for automatic tracking of the tracking unit.

In particular, at least one guide rail preferably has a toothed rack into which engages a toothed wheel which is driven by an electric motor and the other guide rails have guide rollers for guiding the frame.

In an expedient development of the invention, the electric motor has a control with a light sensor, via which the optimum position of the PV modules can be determined to the sun and this position is automatically controlled.

In a first embodiment of the invention, the stands are in a fixed elevation angle for mounting. In a further development of the invention, the stands are movably coupled to the frame, so that their elevation angle changes during a movement of the frame. A preferred embodiment of the invention is explained below with reference to the accompanying drawings.

It shows:

1 is an oblique view of a support structure according to the invention with three PV module stands,

2 is a side view of Fig. 1,

Fig. 3 is an oblique view of a support structure according to the invention with a PV module stand, a plan view of a Tragkonstruk tion according to the invention wherein only the holder and the movable Rah men are shown and

Fig. 5 is a plan view of a support structure according to the invention with dashed lines shown twisted position of the tracking unit.

Fig. 1 shows an exemplary embodiment of the invention. The support structure 1 shown has a holder 2 and a tracking unit 3, on which three stands 4 for receiving photovoltaic modules (PV modules) 5 are attached. Both framed and unframed PV modules can be used.

The stands 4 have a fixed elevation angle β, which is preferably selected depending on the geographical location of the site. In this case, one or more PV modules 5 can be arranged on each stand 4, depending on the size of the uprights and the modules. For fastening the uprights 4 to the tracking unit 3, essentially U-shaped attachments 6 are provided, wherein the two U-legs have different lengths depending on the elevation angle β (FIG. 2). In the example, each stand 4 has three such fasteners 6. However, the number can be varied as desired with the size of the stand 4. However, the uprights 4 can also be fastened differently to the tracking unit 3.

Framed PV modules can be attached directly to the U-shaped mountings on the tracking unit, while frameless PV modules require additional support on the stands. The support structure 1 according to the invention is not limited to three stands 4. Rather, the number of stands is almost arbitrary. In Fig. 3 by way of example a support structure 1 is shown with only one stand 4, which substantially corresponds to the support structure of FIG.

The essential features of the invention can be seen in FIG. The embodiment shown in the example also has three PV module stand 4, wherein here too the number is almost arbitrary. The fixed bracket 2 has a total of six circular curved guide rails 7, which are firmly connected to a base, such as a roof or an intermediate structure. The curvature of the guide rails 7 extends parallel to the mounting plane. In the example, the guide rails 7 are each arranged in pairs opposite one another, wherein the curvature of the rails 7 of a pair is oriented in opposite directions. In the middle between the guide rails 7 a likewise fixedly connected to the base or the roof longitudinal rail 8 is arranged. The tracking unit 3 has a substantially rectangular frame 9, which is formed in the example by aluminum profiles. The distance of the paired guide rails 7 is determined by the width of the frame 9. The pairs themselves are each arranged identically offset along the length of the frame 9.

In the example, the frame 9 has two longitudinal struts 10 and six transverse struts 11, wherein the longitudinal and two transverse struts define the edge of the frame 9. The remaining cross struts are arranged equidistantly between the two edge cross struts 11 in parallel, wherein for each guide rail pair each two adjacent cross struts are necessary, which are divided into first and second cross struts.

In the example of FIG. 4, the lowermost transverse strut 11 is a first transverse strut. Upwards follow alternately a second and again a first cross strut.

The guide rails 7 on the right side of the image are now arranged so that each of the beginning is tangent to the junction 14 of a first cross member 11 with the right longitudinal strut 10. At this point, a guide roller (not shown) is arranged on the frame 9, which engages in the guide rail 7. At the lower right corner, the guide rail 7 deviating from a rack 12, in which engages a gear which is driven by an electric motor 13. In the example, the electric motor 13 is fastened to the lowermost transverse strut 11.

The opposite guide rails 7 on the left side of the image are each arranged so that each of the beginning tangent to the junction 14 of a second transverse strut, 11 with the left longitudinal strut 10 is located. Here, too, 14 guide rollers are arranged in each case at the connection points, which engage in the guide rails 7.

The individual transverse and longitudinal struts are each rotatably connected to each other by bolts or screws. Furthermore, the transverse struts 10 are rotatably mounted on the central longitudinal strut 8 of the holder 2, wherein the respective attachment points 15 form the axis of rotation for the tracking unit 3.

Now, if the electric motor 13 is activated, the gear drives the rack 12 of the guide rail 7, whereby the corresponding connection point between the first transverse strut 11 and the right longitudinal strut 10 along the guide rail 7 is moved on a circular path. The other connection points with guide rollers follow this movement through the respective backdrop-like guided storage of the guide rollers in the other guide rails. 7

Since all connections between the individual struts of the frame 9 are designed to be rotatable, the scissors-like constructed frame 9 is deformed in a parallelogram in total.

In Fig. 5 such a deflected position is indicated by dashed lines. As can be seen, the azimuthal angle α of the PV modules 5 is changed by the parallelogram-like deformation of the frame 9. The support structure 1 according to the invention thus enables the azimuthal tracking of the PV modules according to the daytime course of the sun.

The rotation also changes the distance between the uprights 4, so that the maximum retractable azimuth angle α is mainly determined by the distance of the uprights 4 in the base position. ment is determined, since a touch of the stator 4 should be avoided. Likewise, if the distance between the stands 4 is too small, mutual shading of the PV modules 5 takes place, which leads to a lower yield.

The support structure 1 according to the invention is very simple and has compared to a fixed construction only little extra weight, so that an installation on a private house or a residential building is easily possible. Another advantage is that, due to the rotation, the support structure does not require any width in the width and only little additional space in the length.

With the support structure according to the invention can now also large solar panels azimuthal the daily course of the sun be tracked, at least in a relatively wide range. As a result, the average yield of a solar system with elevated PV modules can be increased on average by up to 35% over a single day.

A preferred embodiment of the invention provides that the stand are attached to the frame via a rotatable suspension, which allows a change in the elevation angle ß. The upper edge of a stand is connected via a rotatably mounted strut with a longitudinal strut of the frame. When the frame is moved, the distance between the upper stand edge and the longitudinal strut changes, which automatically changes the elevation angle ß of the stand. Thus, a biaxial tracking of the PV modules can be achieved with simple means.

The support structure according to the invention can be composed in all versions of lightweight aluminum profiles, so that the total weight is very low and thus a mounting on a flat or pitched roof of a residential building or a garage for private purposes is possible. Due to the simple construction, the invention is only slightly more expensive than a fixed stator mount for PV modules, the additional costs are quickly amortized by the significantly increased yield.

Depending on the design of the frame, it is also possible that fewer guide rails are used. In the example, for example, the two middle guide rails could be omitted, the frame, in particular the longitudinal struts, however, must be designed to be stable in order to accommodate the additional load of the central PV module.

/ Claims

Claims

claims

Support structure for photovoltaic modules (PV modules) (5), with a fixed support (2) which can be fastened on a flat surface, for example a flat roof, and with a tracking unit (3) which has at least one stand (4) the at least one PV module (5) can be fastened and which is movably mounted on the holder (2) in order to enable a tracking of the PV modules (5), characterized in that the holder (2) at least two fixed, circular arc-shaped Guide rails (7) which are aligned parallel to the mounting plane, wherein the curvature of at least one guide rail (7) against the curvature of the other guide rail (7) is aligned, that the tracking unit (3) has a self-supporting frame (9), which is guided in the guide rails (7), wherein the frame (9) is deformable parallelogram, whereby the azimuth angle () of the stator (4) is variable and that the stator (4) is attached to the frame (9).

Supporting structure according to claim 1, characterized in that at least one guide rail (7) has a motor drive for automatic tracking of the tracking unit (3).

Support structure according to claim 1 or 2, characterized in that at least one guide rail (7) has a toothed rack (12) in which engages a toothed wheel, which can be driven by an electric motor (13) and the other guide rails (7) rollers for guiding the Tracking unit (3) have. Supporting structure according to claim 3, characterized in that the electric motor (13) has a control with a light sensor, via which the optimum position of the PV modules (5) can be determined to the sun and this position is automatically controlled.

Supporting structure according to claim 1, characterized in that the holder (2) centrally between the guide rails (7) has a pivot bearing for the tracking unit (3).

Supporting structure according to one of claims 1 to 5, characterized in that the uprights (4) are at a fixed elevation angle (β) to the tracking unit.

Supporting structure according to one of claims 1 to 5, characterized in that the uprights (4) are movably coupled to the guide unit (3) so that their elevation angle (β) changes during a movement of the guide unit (3).

/ Summary