WO2009040065A2 - Photovoltaic system, and tracking method - Google Patents

Abstract

A solar power system is described which can be operated in a particularly economical fashion and comprises preferably low-focusing reflector modules that are placed in a row, a linear power converting arrangement extending within the focus of the reflector modules, and a tracking device that positions the reflector modules according to the position of the sun. Said solar power system is characterized in that the power converting arrangement is formed by photovoltaic elements which are preferably optimized for application of 4 to 20 times the intensity of light, while the reflector modules and the photovoltaic elements are supported and stabilized by a tensioning cable arrangement. Said tensioning cable arrangement has at least two substantially parallel tensioning cable winches that peripherally extend through guiding members which are disposed perpendicular to the cable arrangement and can be synchronously driven for tracking the reflector modules and the photovoltaic elements.

Description

 description

Photovoltaic system and method for tracking

The invention relates to a solar system in the embodiment as a photovoltaic system according to the preamble of patent claim 1, and a method for tracking a photovoltaic system.

Solar technology is the direct conversion of radiant energy of the sun (or solar energy) into usable forms of energy. Here, the spectrum of solar technology is divided into different sub-areas, which gain from solar radiation either heat or electrical energy.

With the help of solar collectors in a solar system, a heat carrier such as water is heated by the solar energy and provided to the user in the form of hot water, or an energy conversion supplied to usable electricity.

In contrast, in a photovoltaic system, the radiation energy of the sun is converted directly via the solar cells into electrical energy, which is available to the user as solar power.

From the prior art according to DE 91 11 028 U1 a solar system with the features of the preamble of claim 1 is known. In this system, a parabolic trough, which consists of several reflector rows, biaxially tracks the sun. This precise tracking is required because the reflectors concentrate the sunlight more than a hundredfold in a focal line in which a tube through which a medium flows is positioned. Such a system can only be operated economically if during tracking the closest movement and positional tolerances are maintained, which requires a complex construction.

In addition, various rope-based wearing and stabilizing known systems. For example, in the Jawerth cable tie, an intermediate cable connects the carrying cable with a tensioning cable, so that the carrying cable is subjected to prestressing. If the suspension cable is now loaded with weight, it largely retains its geometric shape, since the tensioning cable counteracts the additionally introduced force.

Compared to the known photovoltaic systems, the invention has for its object to provide a solar system, which achieves the highest possible overall economic efficiency with a simple basic construction as possible.

This object is achieved by a solar system in the embodiment as a photovoltaic system with the features of claim 1 and by a method for tracking a photovoltaic system with the method steps according to claim 25.

According to the invention, the system is designed as a photovoltaic system with a special design and fixation of the linear focusing reflector module arrangement formed by at least one module and the linear photovoltaic elements extending in the focus of the reflector module arrangement. The photovoltaic elements can also be designed as modules, which are preferably formed by a single row of monocrystalline silicon cells. The tracking device which positions the reflector module arrangement and the photovoltaic elements in accordance with the position of the sun acts according to the invention on the cable arrangement which supports and stabilizes the reflector module arrangement and the photovoltaic elements and consists of tensioning cable runs which run essentially parallel to one another. For tracking the tensioning cables are guided at the edge by perpendicular to the cable arrangement arranged guide body, which are synchronously driven, preferably pivoted. It has been shown that with this construction, an optimum of energy yield and construction-technical effort can be achieved, resulting in a special economy of the system. In principle, it is possible to form the reflector module arrangement in the form of a long strand, which can support a support structure for the photovoltaic elements at regular intervals. However, it is also possible to use a plurality of linearly aligned and juxtaposed individual reflector modules. Because of this basic design, the present invention low-focusing photovoltaic system can be very simple. It has been recognized that the lightweight mounting and tracking of the reflector modules and photovoltaic elements according to the invention is in particular readily sufficient to keep the energy conversion rate at the desired level if the degree of focus is 4 to 20 times, for example 10 - is limited to 15 times. Because in this case it does not depend on a high-precision positioning of the photovoltaic elements exactly in a focal line. Rather, certain positional and alignment deviations can be accepted without noticeably impairing the efficiency. This results in the additional advantage that the photovoltaic elements require less expensive cooling.

In principle, the photovoltaic system according to the invention can be satisfied with a uniaxial tracking, since it works only with a low-focusing reflector. The angular deviations resulting from the compliance of the construction between the position of the driven guide bodies and the reflector modules located therebetween may e.g. definitely up to 2 to 3 °. The structure of the photovoltaic system according to the invention can therefore work with a conceivable simple tracking device, which simultaneously controls a plurality of modules. It also makes it possible to build the system in the longitudinal direction almost arbitrarily long, because the system weight per running meter is very low. The poorer efficiency of the system resulting from the inaccuracy of the focusing properties of the reflector module arrangement as a result of the lightweight construction of the cable arrangement and the reflector module arrangement fastened thereto can be compensated by correspondingly more efficient photovoltaic elements. This gives the particular additional advantage that the photovoltaic element modules are manufactured using conventional technologies, e.g. Silicon technology can be produced without noticeable additional costs. For example, the silicon solar cell designed for a 10-fold (but also for a 4 to 20-fold) concentration of the sunlight can be produced with virtually the same effort as a cell designed for direct irradiation.

The system according to the invention is therefore in particular a low-focussing system To operate particularly economically, since this inaccuracies in the positioning of the photovoltaic elements not noticeably affect the effectiveness of the system. But also inaccuracies in the position of the focal line can be taken with the inventive design of the photovoltaic system in purchasing, making it possible to design the reflector modules also in lightweight construction and possibly with a simplified geometry, eg as a cylindrical shell segment. As a result, the support structure is relieved, resulting in an even simpler structure. It is even possible to form the reflector modules as a kind of reflector "sail", which is sufficiently stabilized by the tensioning cables. Wind-induced deformations of the reflector modules can be accepted due to the low-focussing system without noticeably reducing the efficiency.

The basic principle of the photovoltaic system shows that ropes are stretched to support and stabilize the reflector module assembly between guide bodies, so that the tensioned between guide bodies ropes serve as a kind of framework for the stabilizers mounted therein, which carry the reflector module assembly.

A variant of the photovoltaic system shows essentially parallel ropes, which makes a particularly simple construction of the photovoltaic system possible. In addition, there is an advantage when the ropes are stretched in the manner of a traverse. The arrangement of the preferably parabolic running to the line of symmetry tensioning cables based on the static principle of Jawerth - rope binder. In this design variant, the vertically downwardly acting weight forces of the reflector module assembly over the prestressed tension cables are minimized. The course of the tensioning cables essentially corresponds to that of a parabola, the tensioning cables, as seen from the end of the reflector module arrangement towards the line of symmetry, being executed further and further from the exterior of the reflector modules toward the axis of rotation of the reflector module arrangement. In a further embodiment of the photovoltaic system, it is advantageous if the cables are parabolic on a horizontal plane, the plane passing through the center of gravity of the reflector module arrangement.

A light and structurally simple photovoltaic system consists of two tension cables gen, which carry the reflector modules. The photovoltaic system is given additional stability if it is equipped with three tensioning cables which, when viewed in a plane perpendicular to the tensioning cables, are at a height level or at the apex and in the area of the two edge points of the reflector surface, thus providing a symmetrical structure Plant is created. However, it should already be emphasized at this point that an asymmetrical arrangement of the tensioning cable is possible, in which case a special design of the reflector modules makes sense.

The tensioning cables, which are interconnected at regular intervals by stabilizers, stabilize the entire photovoltaic system and make it more torsionally rigid. The stabilizers consist of an array of spokes which are attached to the ropes and support each other. For this purpose, one end of the spoke, preferably via a cable clamp, attached to the tensioning cable, wherein migrates in the parabolic arrangement of the ropes of this attachment point from the end of the spoke to the holding element of the photovoltaic element. Alternatively, the segment ring can also provide a connection to the tensioning cable, in which case the end of the spoke is fastened at any point of the segmental ring and the spoke leads therefrom in the direction of the focus of the reflector modules.

It is particularly advantageous if a spoke in a 0 ° position of the reflector module arrangement, in which the two leg ends of the reflector modules are located on a substantially horizontal plane, run horizontally, so that the two leg ends of the reflector modules are spaced apart from one another. Run vertically, so that the vertex of the parabolic reflector modules is stabilized at a predetermined point.

In order to additionally stiffen the stabilizers of the reflector module arrangement located at the ends, these spoke arrangements are provided with further spokes, wherein these have further receivers for tensioning cables and can be supported and stabilized by these.

Generally valid for the photovoltaic system according to the invention is that the stabilizer has particularly good properties, if the spokes are designed symmetrically in their arrangement and lead from their attachment point to a common point, which is preferably in the focus of the reflector modules and there receive at its common point a holder carrying the energy converter assembly consisting of photovoltaic elements.

The, depending on the embodiment, attached to the stabilizers or directly to the tension cables segment rings serve to accommodate the reflectors. The attachment points between the segment rings and the tensioning cable can be embodied as receptacles in the segmental rings, which guide a cable, or as cable clamps which fasten the segmented ring to a cable. The segment ring also serves as a mounting surface of the reflector modules. It is particularly advantageous if the cross-section of the segment rings is designed to be angular and has receptacles into which the reflector modules can be inserted and fastened in order to give them particular hold and stability.

According to an advantageous development of the photovoltaic system are located between the segment rings reflector modules, considered in a plane perpendicular to the extension of the tensioning cables, have substantially the cross-sectional shape of a circular gens, which in addition to the advantageous symmetry, a particularly simple construction of the photovoltaic system is achieved. Furthermore, this measure makes it possible to produce the individual components of the system uniformly and thus more cost-effectively. As a particularly economical and technically feasible cross-sectional shape, the parabolic cross-sectional area has been found with the dimensions of about 4 meters wide and about 1, 1 meter in height. It should be emphasized that, of course, any other, the required focus of the sunlight ensuring cross-sectional shape of the reflector modules, such. B. a geometry in the manner of a parabolic mirror, can be selected without departing from the spirit of the invention. The reflector modules, which lined up and attached to each other form the reflector module assembly form on its inner side of the arc a surface reflecting the sun's rays. The reflector modules can therefore have a support element with applied mirror foil or a reflective coating, wherein the support element of fiber, preferably glass fiber reinforced plastic fabric, a sandwich panel or a sheet metal with introduced stiffening edges, wherein the reflector module can be equipped on the edge side with coupling sections, which serve for attachment to the segment rings or the adjacent reflector modules.

The construction of the photovoltaic system makes it possible for the reflector module arrangement mounted in a cable arrangement to be aligned by a pair of guide bodies according to the course of the sun so that the best possible efficiency of the photovoltaic elements prevails in the focus of the reflector modules at all times. The guide body in this case have driving points for the tensioning cables, which are in fixed positional relationship to each other and preferably lie on a segment ring which is radially mounted, whereby during the rotational movement of the tracking the position of the tensioning cables can be maintained to each other in an unchanged position. In an advantageous embodiment of the photovoltaic system, the guide body preferably consists of a curved base element, which is supported on a guide unit. In this case, the base member runs on at least two support rollers or support roller pairs, which are in the side distance to each other, each support roller or each pair of support rollers is associated with a counter-roller or a Gegenhalterrollenpaar. By this storage of the guide body in the gap between the rollers a good rotational movement is ensured with good positional fixation. If the support rollers and the counter-rollers designed as wavy bearing body, even more wear-free storage of the guide body is possible, even if the latter slightly tilt during tracking due to changes in rope length. A preferred drive device for the tracking of this guide body is a gear drive which has a stationary mounted motor, preferably a geared motor, and pivots the toothed rod mounted on the segment ring and / or guide body by means of a pinion. The guide body is pivotally supported by the roller bearing assembly on a frame and thus can roll on the frame.

Alternatively, the guide body may also have a substantially triangular symmetrical base body. Its base serves to accommodate the tension cables and the geometric height is used to hold a journal. Advantageously, serve the legs of the triangular body of the stiffening of the Guide body. A particularly good tracking of the reflector module arrangement is achieved when the bearing pin is located in the center of gravity of rotating during tracking components. The bearing pin is preferably performed in this construction in a rolling bearing, which is arranged on a column, which on the one hand, the photovoltaic Anläge spaced to the ground and on the other absorbs rope forces. A simple tracking of the reflector module assembly can be achieved if a pinion is arranged on the bearing pin, which is driven by a motor attached to the column via a chain or a toothed belt.

By designing the energy converter assembly with two photovoltaic elements angularly connected in such a manner as to impinge the reflected solar rays perpendicularly to the surface of the photovoltaic elements, the efficiency of the energy converter assembly is higher than if it encounters an acute angle when using only one photovoltaic element , The novel design of the energy converter arrangement makes it possible to design the reflected solar radiation through a further upturned parabolic cross section of the reflector module arrangement more efficiently the efficiency of the energy converter arrangement, whereby a flat structure with less resistance surface of the photovoltaic system is made possible because the energy converter assembly immerse itself further into the reflector module arrangement can. In addition, this geometric design of the photovoltaic system allows the guide body particularly simple to perform as a simple linear profile, since the attachment points of the tension cables and the attachment points of the energy converter assembly lie on a horizontal plane.

Advantageously, the system fulcrum of the photovoltaic system is in the center of the rotating components, in order to allow the most symmetrical construction of the photovoltaic system. Alternatively, the system fulcrum of the photovoltaic system is at the center of gravity of the rotating components to minimize tracking leverage.

A particularly accurate tracking and a particularly low torsion of the reflector module arrangement are achieved if the guide bodies are driven synchronously by means of a drive device. The tracking can be done by means of an Risch drive done, which is tracked to the sun. Another drive variant provides to hydraulically drive the guide body by means of a time-dependent tracking.

The inventive method for tracking a photovoltaic system has a cable assembly with attached reflector module assembly, which is aligned by a so-called guide body according to the Sun's course such that at any time in the focus of the reflector modules best possible efficiency of the photovoltaic elements is achieved. The cable arrangement is preferably tracked on one side together with the reflector module arrangement by the entire cable arrangement being pivoted over the guide bodies.

The invention further relates to a reflector module, a stabilizer and a photovoltaic module for a photovoltaic system according to the invention. In order to keep the weight of the reflector modules low, the support element is preferably lightweight, such. B. made of a lightweight material such as carbon or glass fiber reinforced plastics or lightweight sandwich construction.

According to a further embodiment of the stabilizers, this consists of a Traverse with a pair Spannseilangriffspunkten and an angle, preferably perpendicularly extending strut having a support for a photovoltaic element and below a Spannseilsangriffspunkt, wherein the stabilizer at least one segment ring to Recording a reflector module is attached. Additional stabilizer spokes stabilize and support the mounting for the photovoltaic element.

The design of the photovoltaic module according to claim 32 is therefore particularly advantageous because it makes it possible to construct the reflector arrangement flat and with a favorable cross section and at the same time to ensure optimum energy yield.

Embodiments of the invention will be explained in more detail with reference to schematic drawings. Show it:

Figure 1 is a partial side view of a photovoltaic system according to the invention in minimum pivot position (orientation when the sun is in the zenith);

Figure 2 on a slightly enlarged scale, the view "11-11" in Figure 1;

Figure 3 is a plan view of the photovoltaic system according to Figures 1 and 2 according to "III" in FIG

1 ;

Figure 4 is a side view similar to Figure 1 of the photovoltaic system according to the invention in almost maximum pivoting position;

Figure 5 is a view similar to Figure 2 of the photovoltaic system of Figure 4 viewed along the arrow "V";

Figure 6 on an enlarged scale, the detail view "VI" in Figure 4;

Figure 7 on an enlarged scale, a detail in the area "VII" of the photovoltaic system of Figure 3;

Figure 8 on an enlarged scale, the view of the detail "VIII" in Figure 2;

Figure 9 on an enlarged scale, the view of the detail "IX" in Figure 4;

Figure 10 is a side view of another modified embodiment of the photovoltaic system;

Figure 11 on an enlarged scale a sectional view of a modification of the reflector module according to the invention;

Figure 12 is a schematic side view of a modified embodiment of a guide body or "tracker" for the photovoltaic system;

Figure 13 is an overall perspective view of a photovoltaic system; Figure 14 is a perspective view of a photovoltaic system according to a second embodiment;

FIG. 15 shows a partial side view of a photovoltaic installation according to the invention, measured according to the second embodiment, in a minimal pivoting position (orientation when the sun is in the zenith);

Figure 16 is a plan view of the photovoltaic system according to the second embodiment;

17 shows the view of a support post order according to the second embodiment on an enlarged scale;

FIG. 18 shows the cross section of the photovoltaic system according to the second embodiment;

19 shows the detail of a fastening in the region of the segment ring according to Au of the second embodiment;

Figure 20 is a side view of the photovoltaic system according to the invention according to A of the second embodiment in almost maximum pivoting position;

Figure 21 shows the cross section of the photovoltaic system according to the second embodiment in almost maximum pivot position;

FIG. 22 is a perspective view of a photovoltaic system according to a third embodiment;

Figure 23 is a partial side view of a photovoltaic system according to the invention according to the third embodiment in a minimum pivotal position (orientation when the sun in the zenith);

Figure 24 is a plan view of the photovoltaic system according to the third embodiment;

FIG. 25 shows the cross section of the photovoltaic system according to the third embodiment; Figure 26 is a side view of the photovoltaic system according to the invention according to the third embodiment in almost maximum pivot position;

Figure 27 shows the cross section of the photovoltaic system according to the third embodiment in almost maximum pivot position;

FIG. 28 is a perspective view of a photovoltaic system according to a fourth embodiment;

Figure 29 is a partial side view of a photovoltaic system according to the invention according to the fourth embodiment in a minimum pivotal position (orientation when the sun in the zenith);

FIG. 30 is a plan view of the photovoltaic system according to the fourth embodiment;

FIG. 31 shows the view of a support post arrangement according to the fourth embodiment on an enlarged scale;

FIG. 32 shows the cross section of the photovoltaic system according to the fourth embodiment;

FIG. 33 shows a side view similar to FIG. 28 of the photovoltaic system according to the invention according to the fourth embodiment in almost maximum pivoting position;

Figure 34 shows the cross section of the photovoltaic system according to the fourth embodiment in almost maximum pivot position; and

FIG. 35 shows the detail of a bearing of the guide body on the frame according to the fourth embodiment.

FIG. 36 is a perspective view of a photovoltaic system according to a fifth embodiment; Figure 37 is a partial side view of a photovoltaic system according to the invention according to the fifth embodiment in a minimum pivotal position (orientation when the sun in the zenith);

Figure 38 is a plan view of the photovoltaic system according to the fifth embodiment;

FIG. 39 shows the view of a support post arrangement according to the fifth embodiment on an enlarged scale;

FIG. 40 shows the cross section of the photovoltaic system according to the fifth embodiment;

FIG. 41 shows a side view similar to FIG. 36 of the photovoltaic system according to the invention according to the fifth embodiment in almost maximum pivoting position;

Figure 42 shows the cross section of the photovoltaic system according to the fifth embodiment in almost maximum pivoting position;

Figure 43 shows a detail of a coupling situation of the solar system according to the fifth embodiment;

Figure 44 is a perspective view of a photovoltaic system according to a fifth embodiment with a polygonal tensioned central rope; and

Figure 45 is a perspective view of a photovoltaic system according to a fifth embodiment with a polygonal tensioned central cable under bias.

In the following, five embodiments of the photovoltaic system according to the invention will be described. The general construction of the photovoltaic system, consisting of a reflector module arrangement, which is stretched over tensioning cables between guide bodies, which tracks the position of the sun and is guided by stable substructures and tensioning cables in their position, will be described with reference to a first embodiment. wrote. Beyond going features and advantageous developments of the invention will be described in the other embodiments, wherein the further explanation of already as the first embodiment known features is omitted.

Figure 1 shows a schematic partial view of the structure of a photovoltaic system according to the invention, as it should be used in large-scale systems for the production of solar energy. An overall arrangement of the solar system is shown schematically in FIG. 13, to which reference should already be made here.

The solar system, shown in Figure 13 only one of a marginal guide body 40 to a first auxiliary guide body 40Z running portion extends with a length L, which may be some 100 m, and a variable width B, which - adapted to the local conditions - can also be considerable. It is composed of substantially linear, parallel-aligned photovoltaic modules 20 with reflector-gutter assemblies 22 and linear photovoltaic elements 28, which are aligned in north-south direction. The solar system is used in areas of high solar irradiation rate, e.g. placed in desert areas, preferably in areas of low latitudes, so that sufficient to ensure a sufficient energy yield a uniaxial tracking around the longitudinal extension longitudinal axis LAE.

The peculiarity of the solar system consists in the way in which the reflector trough arrangements 22 and linear photovoltaic elements 28 are constructed, stabilized and tracked according to the position of the sun. For the description of the details of a first embodiment, reference is made to Figures 1 to 9.

In detail, each photovoltaic module 20 has a reflector channel arrangement 22, which is formed by a reflector module arrangement 26 in the form of a plurality of aligned, focusing reflector modules 26-1 to 26-n, one extending in the focus of the reflector module arrangement 26 linear energy converter arrangement 24 in the form of the linearly aligned solar cell Photovoltaic elements 28 (for example, in the embodiment as silicon photovoltaic elements 28), and a reflector module assembly 26 and the photovoltaic elements 28 according to the position of the sun positioning tracking device. The reflector modules 26 and the photovoltaic elements 28, which are formed, for example, by photovoltaic element segments 28-1 to 28-n of the same or a length x times that of the reflector modules 26-1 to 26-n, are under tension Rope arrangement worn and stabilized.

The cable arrangement has at least two, in the illustrated first embodiment of Figures 1 to 9, three mutually parallel tensioning cables 30, 32, 34, which at both ends of the photovoltaic system 20 - in the figures, only one end of the photovoltaic system is shown - by perpendicular to Rope arrangement arranged guide body 40 extend. The guide body 40, which in the embodiment shown have the shape of bent to circular ring segments double T-beams with a web and two segment ring bands are synchronized to track the reflector modules 26 and the photovoltaic elements 28 about an axis 42 drivable in the embodiment shown coincides with the center of the annulus segment. The tensioning cables 30, 32, 34 are preferably formed by steel cables.

As can be seen in FIGS. 2 and 8, the guide body 40 for the tensioning cables 30, 32 and 34 has a corresponding number of driving points 42, 44, 46 which are in fixed position relation to one another. The guide body 40 in the form of the circular ring segment, is pivotally supported on a frame 49 via a roller bearing assembly in the embodiment of two mutually spaced from each other standing support rollers 48 on the outer segment ring band 52 and thus can roll on the frame 49.

In order to additionally stabilize the guide body, each support roller 48 is associated with a counter roller 50 or a counter roller pair, so that the outer segment ring band 52 of the guide body 40 is guided in a gap 54 between the rollers 48 and 50. For tensioning the tensioning cables 30, 32, 34, these are guided from the guide body 40 to an anchoring point 60 on a foundation 61, which is arranged to the adjacent guide body 40 in a lateral minimum distance AM, the meaning of which is explained in more detail below. In the exemplary embodiment shown in FIGS. 1 to 9, tensioning cable sections 3OS, 32S, 34S converge essentially in a tensioning point 62 which is formed by an anchor plate 64 which carries cable couplings 66. The cable couplings 66 are, for example, designed such that the length of the individual tensioning cable sections 3OS, 32S, 34S can be set individually.

Another peculiarity of the embodiment of Figures 1 to 9 is that the clamping point 62 at the upper end of a pendulum support post assembly 68 is located, which may have either a single support post or a pair of support posts, which is supported on the foundation 61 preferably limited resiliently. Thus, on one side of the support post assembly 68, the tensioning cable sections 3OS, 32S, 34S engage and on the other side an anchoring cable 70 engages, which runs under tension to the foundation 61.

In the tensioning cable arrangement, preferably between the foundation 61 and the guide body 40, at least one spring-damping unit 74 can be incorporated.

As can be seen from Figures 1, 3 and 4, the tension cables 30, 32, 34 carry the reflector modules 26-1 to 26-n, which are preferably made in lightweight construction, so that can be spoken of a kind of "solar sailing" can be formed by flexible mirror films, which then run in suitable guide bodies, which hang on the tensioning cables 30, 32, 34, or they consist of brought into a specific shape support elements 72, to which a mirror film 76 is applied made of fiber-reinforced, such as glass fiber reinforced plastic and they may also have a film shape.

As can be seen in detail from FIGS. 2 and 7, the carrier elements 72 are provided at the edge with a flange 73, which serves as a coupling section to the associated tensioning cables 30, 32, 34 and to adjacent carrier elements 72. The coupling takes place in detail via a two-part cable clamp 78, the inner part 78Rl carries a radial web 79, via which the flanges 73 are screwed together and thus at the same tensioning cable 30, 32 and 34 are fastened simultaneously.

In addition, the radial webs 79 can be connected to one another via a circular-arc-shaped segment ring (not shown in greater detail and extending essentially along the parabolic shape of the reflector surface), which allows greater stability to be achieved. A coupling of adjacent reflector modules 26 can then take place at additional locations 83 (see FIG. 1 and FIG. 5) via the segment ring, in that the annular flanges 73 are screwed together as shown in FIG. However, it is equally possible to replace this indirect coupling of adjacent reflector modules 26 via a segment ring 52 of the stabilizer 57 by a direct coupling, in which case non-positive or positive connections are applicable.

In the embodiment shown, the parabolic trough-shaped reflector modules 26 have the cross-sectional shape of a circular ring segment whose center substantially coincides with the center point 42 of the annular segment of the guide body 40 (see FIG. 2). However, the mirror surface formed by the mirror film 76 extends over a smaller central angle than the annular segment of the guide body 40.

In addition to the reflector modules 26, the tensioning cables 30, 32, 34 also carry the photovoltaic elements 28, specifically in the exemplary embodiment according to FIGS. 1 to 9, in that the fastening arrangement is used for selected reflector modules 26. For this purpose, the radial webs 79 are extended to spokes 80 at selected locations, which converge on a mounting platform 82 for the photovoltaic element segments 28-1 to 28-n. The spokes 80 and the mounting platform 82 form in this way, together with the cable clamps 78 stabilizers 77 for the photovoltaic system. In the area of the fastening platform 82, the electrical connection of the photovoltaic elements 28-1 to 28-n, which is not shown in more detail, also takes place. The fastening platform 82 is positioned such that the photovoltaic element 28 fixed thereon essentially comes to lie in the region in which the sun's rays which are incident parallel to the axis of symmetry ASY of the reflector module 26 hit the surface be focused about 10 times.

The photovoltaic elements 28 are preferably constructed as light as possible. For this purpose, the solar cells (for example in the embodiment as silicon solar cells) can be applied to lightweight heatsinks which at the same time give the photovoltaic elements sufficient stability so that a structure is created which, under the influence of gravity, even at module lengths of a few meters is not overly bent and the solar cells are not noticeably shifted out of focus.

In order to optimally expose the reflector modules 26 and thus also the solar cells (for example in the embodiment as silicon solar cells) photovoltaic elements 28 to sunlight, irrespective of the position of the sun. tracking the position of the sun, the guide body 40 are driven synchronously. For this purpose, as best seen in FIG. 8, the frame 49 carries a drive unit 84, preferably equipped with a geared motor, with a drive pinion 86, which meshes with a toothed rack 88 carried by the outer segment ring 52 of the guide body 40. As a result, the guide body 40 are pivoted slowly on both sides of the photovoltaic system 20, wherein the reflector cables 26 and photovoltaic elements 28 are entrained via the tensioning cables 30, 32, 34. The sun's rays therefore always fall parallel to the axis of symmetry ASY and act on the photovoltaic elements 28 with maximum light energy.

In the figures 1 to 3, the orientation of the guide body 40 and therefore also the reflector modules 26 is shown at the time at which the sun is at its zenith. Figures 4 and 5 show the orientation at almost maximum pivoting angle of, for example, + 60 °, when the sun in the morning or afternoon still about 30 ° above the horizon.

It can be seen from FIGS. 2 and 5 that during pivoting of the guide body 40, the position of the driving points 42, 44, 46 for the tensioning cables 30, 32, 34 also changes, while the anchoring point 60 remains quasi stationary. The associated, and for the individual cables different clamping force changes can in part by the spring-damping unit 74 and elasticities of the Tensioning cables 30, 32, 34 are compensated, on the other hand, by the fact that the above-described distance AM of the anchoring point 60 from the guide body 40 is selected such that the respective length of the tensioning cable section 30S ₁ 32S, 34S does not exceed a predetermined threshold during its tracking changes. The support post assembly 68 can then, if it receives the function of a pendulum post, further reduce these changes in length. The distance AM may, for example, be about 20 m. In addition, the guide body 40 can be provided with plain bearings, which allows a lateral movement possibility of up to 10 cm.

Since the photovoltaic elements 28 cooperate with low-focus reflector modules 26, an economic energy yield results even if, on the one hand, a shift caused by wind or gravity of the photovoltaic elements 28 from the focus area within certain limits or on the other hand, an angular deviation of the tracking over the length of the entire photovoltaic module 20 has a limited tolerance of about 2 °. This angular deviation is due to the rope clamping technology centrally between the guide bodies 40 largest. The angular deviation is therefore greater with increasing longitudinal distance between the guide bodies 40. Weather-related influencing factors, such as strong wind speeds, can contribute to increasing the angular deviations.

To reduce the angular deviations, additional tensioning cables 98 may be provided at suitable points of the cable arrangement, preferably at anchoring point 60, at tensioning point 62, on guide body 40 and / or at a cable clamp 78 of spokes 80 and mounting platform 82 Attack stabilizer 77.

In order to minimize these angular deviations, selected stabilizers 77 described above, which are formed by the cable clamps 78, the spokes 80 and the mounting platform 82, may also be provided with a drive which is controlled synchronously with the drive for the guide bodies 40. In this case, a segment ring, which can connect the spokes 80 to one another to increase the stability of the stabilizers 77 and the overall arrangement, is provided on the outside with a Rack equipped, which is driven by a stationary drive unit.

It is also possible to work with one or more additional guide bodies 4OZ, which are installed in the photovoltaic module 20 at regular longitudinal intervals, especially in the case of particularly long longitudinal extensions of the photovoltaic module 20, and otherwise are constructed and driven in exactly the same way as the guide body 40. In Figures 1, 3 and 4, such an additional guide body 4OZ is shown. It can, for example, have a distance of 50 to 100 m from the guide body 40.

The tensioning cables 30, 32, 34 may be continuous from one guide body 40 to the other and optionally to the lying on the other side foundation or support post. In the embodiment shown, however, the tensioning cables 30, 32, 34 are interrupted at the additional guide bodies 40Z, which can be seen from the detail according to FIG. From the additional guide body 4OZ of the photovoltaic system is on both sides in the region of the driving points 42, 44, 46, a tensile member 92, for example, a cable section, before, which is in each case detachably connected to a cable coupling 90.

An exemplary embodiment is described above, in which three tensioning cables 30, 32, 34 are provided which, viewed in a plane perpendicular to the extension of the tensioning cables, lie substantially at the vertex and in the region of the two end regions of the reflector surface. It should be pointed out, however, that the tensioning cables 30, 32, 34 can also be arranged at other positions with respect to the alignment of the reflector modules 26, which is used in particular when non-centric clamping of the photovoltaic elements with respect to the reflector modules 26 is selected. to get around the so-called shading problem.

The photovoltaic system described above is suitable for a wide variety of dimensions, for example, for systems of 10 to 20 m total length. It can be operated particularly economically if the total length of the photovoltaic plant module 20 is several 100 m, the height of which is a few meters, and the length of the reflector modules 26 and / or the photovoltaic elements 28 is in the range between 0.5 and 3 m.

With the solar system described above, a new method for tracking a photovoltaic system is created at the same time, which forms the subject of an invention, especially when it is operated with a photovoltaic module 20, which was explained above. The peculiarity is that reflector modules, which are mounted in a tensioned cable arrangement, are aligned by a pair of guide body according to the Sun, so that at any time in the focus of the collectors the best possible efficiency of the photovoltaic elements is achieved.

A further exemplary embodiment is shown in FIG. 10, which differs from the exemplary embodiment of FIGS. 1 to 9 only with regard to the anchoring of the tensioning cables 130, 132, 134. To simplify the description, those components of the system which correspond to the components of the embodiment described above are given similar reference numerals, but preceded by a "1." The tensioning cable sections 130S, 132S, 134S run directly to the anchoring point 160 at the foundation in this embodiment 161st

With reference to FIG. 11, a further exemplary embodiment of a low-focus photovoltaic module 226 will be described. The special feature is, on the one hand, that this photovoltaic module 226 has an asymmetric focus. In addition, the reflector module, which is formed by a foamed plastic part with Spiegelbe- layering, at the same time carries the photovoltaic elements 228. As outlined, this photovoltaic module 226 requires only a fixation via two tension cables that pass through openings 194. Since the photovoltaic modules 226 is a self-supporting hollow structure or hollow foam structure, the advantage of such a construction is the easier installation of the PV modules and the possibility to use the mirror wall or mirror back wall as a cooling element for the module. However, this variant requires by the oblique adjustment of the mirror to the incident light at the same power a slightly larger mirror surface. Finally, FIG. 12 shows a further exemplary embodiment with a modified drive of the guide bodies, which are designated here by 340. Instead of a gear drive here is a hydraulic drive unit 384 is used, which causes the pivotal movement of the rollers 348 mounted on guide body 340.

The particular advantage of the system described above is that the construction costs drop drastically, especially in large solar power plants. The decisive factor is the combination of low-focussing reflector modules with conventional solar cell photovoltaic technology. Because the production cost of a 10-fold optimized solar cell is substantially the same as that of a single-concentration solar cell, the module-price based on the output power can be reduced 10-fold. The expected production cost of a solar mirror sail according to the invention is estimated at about 0.25 EUR / Wp, which is considerably lower than the cost of glass mirror technology. Finally, because the guide bodies or "trackers" for the tracking of the photovoltaic modules have to be arranged only at very large distances of, for example, 200 m, the construction costs can be further reduced, with an estimated 0.30 EUR / Wp is expected. It is to be expected that the total production costs of the solar system according to the invention will be about 50% lower than for conventional solar power plants.

Embodiment 2 shows a photovoltaic system according to the invention which is tracked by the same principle as Embodiment 1. The tensioning cables 530, 532, 534, 536 shown in FIG. 14 extend in a polygonal manner from one stabilizer 577 to the next, wherein a first tensioning cable is associated with a second tensioning cable such that, viewed in plan view, a first parabolic-shaped pair of tensioning cable trains 530, 532 and a second pair of tension cables 534, 536 is formed whose tension cables each approach each other at their apices and, seen at their ends, are further and further apart from each other. By this arrangement, the tensioning cables 530, 532, 534, 536, the reflector module assembly 26 is biased, which counteract the acting weight forces of the reflector module assembly 26 and contribute to a smaller angular deviation, so that the geometric shape of the photovoltaic system is largely retained. In addition, various rope-based carrying and stabilizing systems are known from statics. For example, in the case of the Jawerth cable tie, an intermediate cable connects the carrying cable with a tensioning cable, so that the carrying cable is subjected to prestressing. If the suspension cable is now loaded with weight, it largely retains its geometric shape, since the tensioning cable counteracts the additionally introduced force.

The segment rings 552 borne by the four tensioning cables 530, 532, 534, 536 on the one hand form a receptacle for the stabilizer 577, which consists of a

A plurality of spokes 80 forms a spoke assembly which carries a holder 82 for the photovoltaic element 28 at a common end of the spokes 80. In particular, the spoke arrangements of the stabilizers 577 located at the beginning and end of the reflector module arrangement 26 have an additional spoke 581 for cross-bracing.

Furthermore, there are fastening receivers for the reflector modules 26-1 to 26-n on the segment rings. These reflector modules 26-1 to 26-n, together with the segment rings 552, the stabilizer 577 and the holder 82 for photovoltaic elements 28, support the reflector module arrangement 26, which is supported by the tensioning cables 530, 532, 534, 536, which are guided by continued tensioning cables 530, 532 , 534, 536 is attached to pivotable guide body 40. In this case, three tensioning cable sections 530S, 532S, 534S transmit the tensioning forces of the tensioning cables 530, 532, 534, 536 to a support post arrangement 568.

FIGS. 15, 16 and 17 show the tensioning cables 530, 532, 534, 536 prestressed to take up the weight forces according to the Jawerth cable tie principle, which are stretched starting from the guide body 40 in a polygonal manner from one segment ring 552 to the next, and thereby to the center approaching the Photovoltaikanla- ge approaching each other in their distance, so that parabolic Spannseilzugpaare 530, 532 and 534, 536 arise, which are attached by means of rope tensioners 90, 92 to a guide body 40. In this exemplary embodiment, three tensioning cable sections 530S, 532S, 534S are attached to the guiding device by means of cable clamps 90, 92. attached body 40 so as to allow the acting tensioning cable forces via cable couplings 66 to flow into the support post assembly 568.

In addition to the known from the embodiment 1 tracking gear drive shows Figure 18 shows the cross section of a photovoltaic system according to the invention, the segment ring 552 on cable clamps 78, hidden in Figure 18 by the guide body 40, tensioning cable 530, 532, 534, 536 is attached. Also attached to this segment ring 552 are the spokes 80 of a stabilizer 577 which carry at a common point of the spoke assembly a mounting platform 82 on which a photovoltaic element 28 is mounted. To stiffen, especially the edge stabilizers 577 and segment rings 552, there is an additional spoke 581, which is to support a stabilization of the circular arc-shaped cross-sectional shape of the reflector modules 26-1 to 26-n.

In Figure 19, a tensioning cable 530, 532, 534, 536 can be seen, to which a cable clamp 578, supported by an inner part 78Rl and a radial web 79, a segment ring 552 attached. The cross-sectionally angular segment ring 552 has a specific area for receiving the reflector module 26 in which the reflector modules 26-1 to 26-n are supported and stabilized.

The following figures 20 and 21 show the photovoltaic system according to the invention in almost maximum pivot position, in Figure 20 again the polygonal tension cables 530, 532, 534, 536 are seen, which are braced for receiving the acting weight forces according to the Jawerth cable tie principle, and acting Seilzugkräfte on the tensioning cable sections 530S, 532S and 534S to the support post assembly 568 pass. For this purpose, as shown in Fig. 21, the guide body 40 tracked by means of a gear arrangement, whereby the fixed to the guide body 40 tensioning cables 530, 532, 534, 536 are pivoted to which the reflector modules 26-1 to 26-n are attached. By way of the stabilizer 577, which is additionally fastened to the segment ring 552 and whose spokes 80 carry a holder 82 for the photovoltaic element 28, the photovoltaic element 28 is tracked together with the reflector module arrangement 26 aligned with the position of the sun. The third embodiment of the photovoltaic system according to the invention shows in FIG. 22 four tension cables 630, 632, 634, 636 which guide in a polygonal manner between the spokes 80 of a stabilizer 677 carried thereby, each stabilizer 677 having segment rings 652 on which reflector modules 26-1 to 26 -n are attached. The tensioning cables 630, 632, 634, 636 terminate in triangular guide bodies 640, which are rotatably supported by means of bearing pins 648 on a frame 649, the tensioning forces flowing off the support post 668 via tensioning cable sections 630S, 632S and 634S.

The stabilizers 677 carried by the tension cables 630, 632, 634, 636, consisting of a plurality of spokes 80 carrying a holder 82 for the photovoltaic element at a common end of the spokes 80, form a receptacle for the segment ring 652 on which Mounting recesses for the reflector modules 26-1 to 26-n are located. These reflector modules 26-1 to 26-n, together with segment rings 652, stabilizer 677 and photovoltaic element holder 82, form the reflector module assembly 26 supported by the tensioning cables 630, 632, 634, 636, which are connected by continued tensioning cables 630, 632, 634 , 636 is attached to pivotable guide bodies 640. In this case, three tensioning cable sections 630S, 632S and 634S transmit the tensioning cable forces of the tensioning cables 630, 632, 634, 636 to a support post arrangement 668.

FIGS. 23 and 24 show the tensioned cable pulls 630, 632, 634, 636 prestressed to accommodate the weight forces according to the Jawh rope-cable principle, which are stretched from the guide body 640 starting from one stabilizer 677 to the next in a polygonal manner. In this case, the spoke 80 has two receptacles or attachment points for two ropes whose distance from each other is variable. This distance of the attachment points to a spoke 80 decreases the closer the spoke 80 is at the point of symmetry of the reflector module assembly 26. This results in two parabolic tensioning cables whose distance from each other in the region of the guide body 640 large and the center of the system is low. The biasing forces acting on the tensioning cable trains as well as the acting weight forces of the reflector module assembly 26 are delivered to a support post assembly 686. For this purpose, the tension cables 630, 632, 634, 636 via cable clamps 90, 92 on guide bodies 640th which in turn are attached to the support post assembly 668 via three tensioning cable sections 630S ₁ 632S and 634S.

FIGS. 22, 23 and 24 also show the possibility that a plurality of reflector module arrangements 26 can be arranged one behind the other and are mounted via guide body 640 and racks 649, wherein the rotational movement of the reflector module arrangement 26 can be transmitted from one reflector module arrangement 26 to the next during tracking or the reflector module assemblies 26 can be driven separately and synchronously.

FIG. 25 shows the guide body 640 which has been modified in comparison with the exemplary embodiments 1 and 2, whose triangular basic shape accommodates the tensioning cables 630, 632, 634 and 636 on one side, whereby they are fastened in as large a distance as possible from one another by the first attachment of a cable pair at the outermost position Point the base of the triangle and the second attachment point is located in the area of the height of the triangular body. On the opposite side of the guide body 640 are mounted the three tensioning cable sections 630S, 632S and 634S leading to the support posts 668. The triangular basic shape of the guide body 640 is preferably mounted in the center of gravity of the reflector module assembly 26, in which a bearing pin 648 height of the guide body 640 is attached. This pin is rotatably mounted on a frame 649, on which there is also an electric drive 84, which tracks the bearing pin 648 and thus the guide body 640 with the reflector module assembly 26 attached thereto to the position of the sun via a chain or toothed belt drive.

The following figures 26 and 27 show the photovoltaic system according to the invention in almost maximum pivoting position, wherein in Figure 26 again the polygonzugarti- tension cables 630, 632, 634, 636 are seen, which are braced to absorb the acting weight forces according to the Jawerth cable tie principle and transmit the acting cable pull forces to the support post assembly 686 via the tensioner portions 630s, 632s, and 634s. For this purpose, as can be seen in FIG. 27, the guide body 640 is tracked by means of an electric drive 84, as a result of which the tensioning cables 630, 632, 634, 636 fastened to the guide body 640 are pivoted together the reflector modules 26-1 to 26-n are attached. Via the additionally attached to the segment ring 652 stabilizer 677, the spokes 80 carry a bracket 82, the photovoltaic element 28 is tracked together with the, the sun's position aligned reflector module assembly 26.

The fourth exemplary embodiment of the photovoltaic system according to the invention shows in FIG. 28 two tensioning cables 730, 732 which lie on a plane passing through the center of gravity, which leads in a polygonal manner from stabilizer 777 to stabilizer 777. Each stabilizer 777 carries segment rings 752 to which reflector modules 26-1 to 26-n are attached. The tensioning cables 730, 732 terminate at triangular guide bodies 740, which are rotatably mounted by means of bearing pins 748 on a frame 749, wherein the tensioning cable forces flow into the support posts 768 via the two tensioning cable sections 730S, 732S.

The stabilizers 777 carried by the tensioning cables 730, 732, consisting of a plurality of spokes 80, have at a common end of the spokes 80 a support 82 which carries the photovoltaic element 28. In particular, the stabilizers 777 at the beginning and end of the reflector module assembly 26 have an additional spoke for cross-bracing. The stabilizer 777 thus consists of a traverse 781 and a strut 780 extending perpendicular thereto, which has a holder 82 for a photovoltaic element 28 at the upper end and a tension cable attachment point at the lower end, wherein a segment ring 752 for receiving a reflector module 26-1 is provided on the stabilizer 777 is attached to 26-n. These modules 26-1 to 26-n together with the segment rings 752, the stabilizer 777 and the holder 82 for photovoltaic elements 28 carry the reflector module assembly 26 carried by the tensioning cables 730, 732, which are fastened to pivotable guide bodies 740 via further guided tensioning cables 730, 732 is. The two tensioning cable sections 730S, 732S transmit the tensioning forces of the tensioning cables 730, 732 to a support post arrangement 768.

FIGS. 29, 30 and 31 show the tensioning cables 730, 732 prestressed to accommodate the weight forces according to the Jawerth cable-tie principle, which starting from the guide body 740 begin in a polygonal manner on a through the center of gravity guiding plane from one stabilizer 777 to the next, approaching the center of the photovoltaic system in such a way that a parabolic tensioning cable 730, 732 is formed, which is fastened to a guide body 740 by means of cable tensioners 90, 92. Two tensioning cable sections 730S, 732S are fastened to the guide bodies 740 by means of cable clamps 90, 92 so as to act

Spannseilkräfte via cable couplings 66 to flow into the support post assembly 768.

FIGS. 29 and 30 also show the possibility that a plurality of reflector module arrangements 26 can be arranged one behind the other, which are mounted via guide body 740 and frames 749, wherein the rotational movement of the reflector module arrangement 26 can be transmitted from one reflector module arrangement 26 to the next during the tracking or the reflector module assemblies 26 can be driven separately and synchronously.

FIG. 32 shows the guide body modified in comparison with the exemplary embodiments 1 and 2, whose triangular basic shape accommodates the tensioning cable pulls 730, 732 on one side, wherein they are fastened to each other in the greatest possible distance. To this end, the tension cables 730, 732 are located at the outermost point of the base of the triangle and therefrom lead to the adjacent stabilizers 777. On the opposite side of the guide body 740 are the two tension cable sections 730S, 732S which lead to support posts 768. The triangular basic shape of the guide body 740 is preferably mounted in the center of gravity of the reflector module assembly 26 by a bearing pin 748 is attached to a geometric height of the guide body 740. This bearing pin 748 is rotatably mounted on a frame 749, on which there is also an electric drive 84, which tracks the bearing pin 748 and thus the guide body 740 with the reflector module assembly 26 attached thereto to the position of the sun via a chain or toothed belt drive.

The following FIGS. 33 and 34 show the photovoltaic system according to the invention in almost maximum pivoting position, the polygonal tensioning cables 730, 732 again being seen in FIG. 33, which are braced to take up the acting weight forces according to the Jawerth cable tie principle and the acting cable pulls forces on the tensioning cable sections 730S, 732S pass to the support post assembly 768. For this purpose, as can be seen in FIG. 34, the guide body 740 is tracked by means of an electric drive 84, as a result of which the tensioning cables 730, 732 fastened to the guide body 740 are pivoted, to which the reflector modules 26-1 to 26-n are fastened. Via the additionally attached to the segment ring 752 stabilizer 777, the spokes 80 carry a holder 82, the photovoltaic element 28 is tracked together with the aligned sun position reflector module assembly 26.

The mounting of the guide body 740 on the frame 749 is shown again in detail in FIG. A guide body 740 is rotatably mounted on a frame 749 by means of a journal 748 in a rolling bearing. This bearing pin 748 transmits the tracking movements of the drive 84 by means of a gear on the guide body 740. This performs the reflector module assembly 26 to the sun, so that in the focus of the reflector modules 26-1 to 26-n best possible efficiency for the photovoltaic elements 28 prevails.

The fifth embodiment of the photovoltaic system according to the invention shows in Figure 36 three tensioning cables 830, 832, 834, which lead on a horizontal plane through the pivot point of the photovoltaic system, the outer tensioning cables 830, 834 polygonal and the middle tensioning cable 832 straight from stabilizer 877 to stabilizer 877 lead. Each stabilizer 877 carries segment rings 852 to which reflector modules 26-1 to 26-n are attached. The tension cables 830, 832, 834 terminate at horizontally extending guide bodies 840, which are rotatably supported by means of trunnions 848 on a frame 849, wherein the tensioning cable forces flow into the support post 868 via three tensioning cable sections 830S, 832S, 834S.

The stabilizers 877 carried by the tension cables 830, 832, 834, which are formed from a plurality of spokes 80, have at a common end of the spokes 80 a support 83 which supports the photovoltaic element. In this embodiment of the photovoltaic system, the stabilizer 877 is formed from two spokes 80, which are arranged horizontally and thus parallel to the guide body 840, the spokes being carried by the polygonal-tensioning tensioning cables 830 and 834. in which the tensioning cables 830, 834 shift their attachment points on the spokes 80 from their end regions toward their common center point, so that the tensioning cables 830, 834, as seen in plan view, from the guide body 840 via the center of the installation to the guide body of a form a polygon in the form of a parabola. Furthermore, the stabilizer 877 is formed by a third spoke 80 which is perpendicular to the two parallel to the guide body 840 extending spokes 80 and with these spokes 80 has a common point of intersection through which the third tensioning cable 832 runs. Particularly advantageous in this tensioning cable arrangement is that the tensioning cables 830, 834 tension the solar system in the vertical direction by their polygonzugartigen course according to the Jawerth-Binder principle and stiffen while the central tensioning cable 832 performs the centering of the stabilizers and thereby the essential weight of the between the guide bodies 840 loaded components.

FIGS. 37, 38 and 39 show the tensioning cables 830, 834 prestressed to accommodate the weighting forces according to the Jawerth cable tie principle, which are tensioned starting from the guide body 840 in a polygonal manner parallel to one another through the pivot point of the installation from one stabilizer 877 to the next are closer to the center of the photovoltaic system in the way that a parabolic tensioning cable 830, 832 is formed by means of rope tensioners 90, 92 attached to the guide bodies 840. Three tensioning cable sections 830S, 832S, 834S are fastened to the guide bodies 840 by means of cable clamps 90, 92 so as to allow the acting tensioning cable forces to flow into the support post arrangement 868 via cable couplings 66.

FIGS. 37 and 38 also show the possibility that a plurality of reflector module arrangements 26 can be arranged one behind the other, which are mounted via guide bodies 849, wherein the rotational movement of the reflector module arrangement 26 can be transmitted from one reflector module arrangement 26 to the next during the tracking or the reflector module arrangements 26 can be driven separately and synchronously.

Figure 32 shows a further embodiment of the guide body 840, which consists of a Torsionally stiff preferably double-T-Trägerprofii is formed, which accommodates the tensioning cables 830, 834, wherein these fixed in the largest possible distance from each other at the ends of the guide body 840 and the guide body 840 provides a receptacle for the third tensioning cable 832 in the middle. On the opposite side of the guide body 840 are the three tensioning cable sections 830S, 832S, 834S, which lead to the support post 868. The guide body 840 is preferably mounted on a journal 848 which lies below the center of the guide body 840 and at the same time forms the axis of symmetry and the pivot point of the solar system. In this case, the horizontal distance between the bearing journal and the guide body 840 forms a geometric height about whose radius the pivoting range of the solar system runs. Advantageously, the bearing pin is supported by two connecting plates 899 spaced from the guide body 840, these plates serve to stiffen the guide body and provide receptacles for the third tensioning cable 832. This bearing pin 848 is rotatably mounted on a frame 894, to which also an electric drive 84 is located, which tracks the bearing pin 748 and thus the guide body 840 with the reflector module assembly 26 attached to it, for example via a chain or toothed belt drive.

The following figures 41 and 42 show the photovoltaic system according to the invention in almost maximum pivoting position, in Fig. 41 again the polygonal tensioning cables 830, 832, 834 are seen, which are braced to absorb the acting weight forces according to the Jawerth cable tie principle and the acting cable tensile forces over pass the tether portions 830S, 832S, 834S to the support post assembly 868. For this purpose, as shown in Figure 42, the guide body 840 tracked by means of an electric drive 84, whereby the fixed to the guide body 840 tensioning cables 830, 832, 834 are pivoted to which the reflector modules 26-1 to 26-n are attached. By means of the stabilizer 877, which is additionally fastened to the segment ring 852 and whose spokes 80, which are only partially visible in this view, carry a holder 83 which is not visible, the photovoltaic element 28 together with the reflector module arrangement 26 tracks the position of the sun.

For tracking the guide body 840, the bearing journal 848 is rotatably mounted on a frame 849 in a white bearing. This journal 848 transmits the Tracking movement of the drive 84, for example via a gear or belt drive on the guide body 840. This leads the reflector module assembly 26 to the sun, so that in the focus of the reflector modules 26-1 to 26-n best possible efficiency for the photovoltaic elements 28 prevails.

FIG. 43 shows a detailed coupling situation of the solar system according to the invention. In this view, the polygonal tensile tensioning cables 830, 834 can be seen, which are attached by means of cable clamps on the guide body 840 and thus the Spannseilzugkräfte from a reflector module assembly 26 to the next ge ben until these Spannseilzugskräfte at the end of the photovoltaic system via tensioning cables 830S, 832S, 834S can drain on the support post 868. Together with the middle tensioning cable 832 stabilizers 877 are supported, which are formed of a plurality of spokes 80, so as to a guide body 840 parallel spoke results, which spans the width of the reflector module assembly to the right angle another spoke is arranged, with their one end at the common intersection with the horizontally extending spokes 80 forms an attachment point and spans the height of the reflector module arrangement with the other end. The system is particularly torsionally rigid by a holder 83 attached to the common fastening point of the spokes 80, which serves to receive and fix the photovoltaic elements 28i and 28 ₂ , if it has a receptacle for the centrally extending tensioning cable 832.

The energy converter assembly 24 is formed in several parts in this embodiment. Thus, a receptacle for two photovoltaic elements 28i and 28 ₂ , which are arranged at an angle to one another such that their photovoltaic layer, for example silicon layer points in the direction of the reflector modules and reflected solar rays from the reflector modules 26 as possible, is located on the holder 83 meet perpendicular to the energy generating surfaces of the reflector module assembly, whereby the highest possible efficiency of the photovoltaic elements can be achieved. In a further, not shown embodiment of the photovoltaic system according to the invention, the energy converter assembly 24 is formed from a plurality of photovoltaic elements 28i to 28 _n , which are arranged segment-like or facet-like, wherein the Photovaltaikschicht the individual facet-like arranged photovoltaic elements 28 each vertically is aligned with the reflected rays of the sun.

The reflector module arrangement shown in this embodiment consists of individual reflector module elements 26-1 to 26-n, which consist of a trapezoidal sheet whose folds preferably extend in the longitudinal direction of the system increase the torsional stiffness of the reflector modules, and on the inside of which a mirror foil for re - Fraction of the sun's rays is appropriate. The reflector module arrangement shown here with a dimension of about 4 x 1, 1 meter leads to a particularly efficient ratio of size of the reflector surface and weight of the system. In order to reduce the wind resistance of the reflector module arrangement and at the same time to provide an outlet for impurities, but also to facilitate cleaning of the reflector module arrangement, a recess is provided in the middle of the reflector module arrangement 26, which can also be created by juxtaposing two individual quarter-circle-like reflector modules , In order to further reduce the wind load perforations can be introduced into the reflector module assembly 26.

FIGS. 44 and 45 show a further development of the photovoltaic system according to the invention, in which the middle tensioning cable 832 is fastened in a segment-like manner from the first stabilizer 877 on the guide body 844 in the direction of the center of the plant to the spoke 80 extending vertically downwards towards the end directed toward the reflector module arrangement 26. If the third tether 832 as described further and further attached to the plant towards the center of the outer end of the vertical spoke, so is located between the photovoltaic elements 28i and 28 ₂ of the energy converter order a gap through the rope 832 of the spoke 80 can be guided to the spoke 80th By such an attachment of the third cable, a stiffening of the reflector module arrangement in dependence on the horizontally acting force is possible. This arrangement of the third tensioning cable 832 allows the absorption of higher horizontally acting forces. In order to make the system even more torsionally rigid with respect to horizontal forces that can act by wind and dead weight, by introducing bias into the downwardly extending tensioning cable 832, the center of a reflector module arrangement can be lifted upwards in the manner shown in FIG. that it is brought to a safe height in the load case to the ground and does not collide with this. FIG. 45 shows the photovoltaic system according to the invention with a middle tensioning cable 832 which runs downwards in a polygonal manner at an angle to the center of the plant in its two possible states. In a first position of the photovoltaic system, in which the stabilizers 877 have been provided with points for better discrimination, the stabilizers 877 are located on a horizontal plane with the guide bodies 840. If the tensioning cable 832 is preloaded, then the stabilizers 877 begin again Move up until the obliquely downward tensioning cable 832 runs almost completely horizontally from guide body 840 to 840 Führungsungskör-. In this preloaded end position, one or more of the stabilizers 877 can be raised above the height level of the guide bodies 840 in order to counteract forces acting on the solar system, such as wind load or dead weight.

Of course, deviations from the above-described embodiments are possible without departing from the spirit of the invention. Thus, the drive of the guide body 40, 140, 240, 340, 540, 640, 740, 840 is not limited to a pure pivot drive. It can also follow a more complex movement curve, which is particularly advantageous if the system is equipped with mirror surfaces with a higher focus.

Thus, for example, the tensioning cables can also run continuously (for example from one end-side anchoring to the other) and without a mechanical connection through the stabilizers and / or additional guide bodies. The stabilizers and / or additional guide body serve in this way only as a cable guide.

The structure of the reflector modules 26 can be varied within wide limits, as long as a light and sufficiently dimensionally stable structure is created, which withstands the stresses caused, for example, by wind forces without excessive deformation.

The reflector module can be formed, for example, by a self-reflecting or mirrored, parabolic-shaped material plate, such as a self-reflective sheet or a surface-coated sheet, such as steel. It can also have another lightweight support element, on which a mirror foil or mirror is applied. Alternatively, an elastically attached and curved glass mirror may be used.

An alternative to the embodiments described above, for example, can provide that the reflector module is formed by a substantially parabolic sandwich panel in lightweight construction. For example, an inner layer having a thickness of about 0.5 mm is formed by a metal layer (e.g., aluminum) with mirror foil. A middle layer, with a thickness of 5 to 15 mm, consists of a mesh structure of foam or light wood, e.g. Balsa wood, and an outer layer, with a thickness of e.g. 0.5 to 2 mm again of light metal, e.g. Aluminum. The cavity in the middle layer is then preferably filled under vacuum with epoxy resin, whereby a light and dimensionally stable structure is formed. The described structure of the reflector modules is to be regarded as an invention for which self-protection is claimed.

In principle, the reflector module arrangement can-unlike the described modular arrangement-also be formed by a one-piece module string, which then carries a support structure for the photovoltaic elements at regular intervals. With extremely long lengths of the photovoltaic system, however, it is advantageous to use a plurality of reflector individual modules, which are arranged in alignment one behind the other.

The reflector modules 26 may also be perforated so that the wind load can be reduced. In addition, it is conceivable to separate the reflector modules 26, for example in the shading area of the photovoltaic elements 28, so as to minimize wind loads and weight. In this case, the reflector module halves can be stabilized via the stabilizers described above or the segment rings which are coupled to one another and couple the individual fastening points of the spokes in this connection.

In the above, an embodiment has been described in which the photovoltaic elements 28 are supported by stabilizers with a spoke arrangement. However, in order to simplify the cleaning of the mirror surface of the reflector modules 26, it may of Be advantageous to attach the photovoltaic elements 28 on central supports, which are supported by either the stabilizers or the reflector modules 26 itself. These carriers are then in the shading area of the photovoltaic elements 28 and are no longer in the way of a cleaning vehicle.

About the variation of the width of the photovoltaic elements, i. By suitable allocation of a certain width of the photovoltaic element and a width of the beam focus, the underfill / coverage of the focusing can be controlled and thus a further cost optimization can be achieved.

The mirror "sails", which may also be formed by thin metal foils or metal-coated foils, can in this case also be rollable or collapsible in order to protect the system from damage at high wind speeds.

The photovoltaic elements 28-1 to 28-n have been described above as planar monolithic components that are focus area of the reflector modules 26. However, they can also be formed of a plurality of mutually parallel and correspondingly narrower PV rods that are adjacent to each other or even polygonal on a correspondingly shaped and adapted to the geometry of the reflector module 26 carrier can be mounted so that the energy yield can be increased.

In the above, an embodiment in which a reflective mirror foil is used has been described. It should be emphasized at this point that the term "film" used also includes a coating or mirroring of a surface.

Thus, the invention provides a solar system which can be operated particularly economically with rowed, preferably low-focusing reflector modules, a linear energy converter arrangement extending in the focus of the reflector modules, and a tracking device which positions the reflector modules according to the position of the sun. It is characterized by the fact that the energy converter is formed of photovoltaic elements, which are preferably optimized for application with 4 to 20 times the light intensity, and that the reflector modules and the photovoltaic elements are supported and stabilized by a tensioning cable arrangement. The tensioning cable arrangement has at least two tensioning cables extending essentially parallel to one another, which run on the edge side through guide bodies arranged perpendicular to the cable arrangement and which can be driven synchronously for tracking the reflector modules and the photovoltaic elements.

Claims

claims 1. solar system, in particular a photovoltaic system, with a linear focusing and at least one reflector module (26-1 to 26-n) having reflector module assembly (26) in the focus of the reflector module assembly (26) extending linear energy converter assembly (24) and a the reflector module arrangement (26) corresponding to the position of the sun position tracking device, characterized in that the energy converter arrangement of photovoltaic elements (28) is formed and the reflector module assembly (26) and the photovoltaic elements (28) are supported and stabilized by a cable assembly, which are substantially parallel to each other Tensioning cables (30, 32, 34, 130, 132, 134, 530, 532, 534, 536, 630, 632, 634, 636, 730, 732, 830, 832, 834), which are part of a rope-tensioned structure, the as a coherent unit the position of the sun is traceable. 2. Solar installation according to claim 1, characterized in that tensioning cables (30, 32, 34, 130, 132, 134, 530, 532, 534, 536, 630, 632, 634, 636, 730, 732, 830, 832, 834 ) are stretched to support and stabilize the reflector module assembly (26) between guide bodies (40; 140; 240; 340; 540; 640; 740; 840). 3. Solar system according to claim 2, characterized in that preferably tensioned in the manner of a traverse tension cables (530, 532, 534, 536, 630, 632, 634, 636, 730, 732, 830, 832, 834) extend parabolic to the line of symmetry , 4. Solar system according to one of claims 2 or 3, characterized in that two + n (n = 0, 1, 2, 3, ...) tensioning cables (30, 32, 34, 130, 132, 134, 530, 532 , 534, 536, 630, 632, 634, 636, 730, 732, 830, 832, 834) which are provided in an extension (LAE) of the tensioning cables (30, 32, 34, 130, 132, 134, 530 , 532, 534, 536, 630, 632, 634, 636, 730, 732, 830, 832, 834) substantially on a vertical plane through the apex (44) and in the region of the two end regions (42, 46). lie the reflector surface. 5. Solar installation according to one of claims 1 to 4, characterized in that at least one stabilizer (77; 577; 677; 777; 877) for stabilizing the tensioning cables (30, 32, 34; 130, 132, 134; 530, 532, 534, 536, 630, 632, 634, 636, 730, 732, 830, 832, 834) are arranged over their longitudinal extension and supported by them. 6. Solar system according to claim 5, characterized in that the tensioning cables (30, 32, 34, 130, 132, 134, 530, 532, 534, 536, 630, 632, 634, 636, 730, 732, 830, 832, 834) are interrupted at selected stabilizers (77, 577, 677, 777, 877) and equipped with cable couplings (90, 92) on both sides. 7. Solar system according to claim 6, characterized in that the stabilizer (77; 577; 677; 777; 877) has a spoke arrangement, which is preferably formed from a plurality of preferably symmetrically arranged spokes (80), wherein one of the plurality of Spokes (80) in a 0 ° position of the reflector module arrangement (26) substantially perpendicular. 8. Solar installation according to claim 7, characterized in that at a region where the spokes (80) run together a holder (82; 83) for a Photovol- taikelement (28) is formed, wherein the holder (82; 83) both of Stiffening the spoke assembly and the attachment of the photovoltaic elements (28) is used. 9. Solar installation according to one of claims 5 to 8, characterized in that the stabilizer (577; 777) by a crossbar (781) is stiffened, which preferably in an O ° position of the reflector module assembly (26) runs substantially horizontally , 10. Solar system according to one of claims 7 to 9, characterized in that the spokes (80) via a segment ring (52; 552; 652; 752; 852) are interconnected, wherein the preferably angular cross-section of the segment rings (52; - 552 ; 652; 752; 852) preferably has receptacles for reflector modules (26-1 to 26-n). 11. Solar installation according to one of claims 6 to 10, characterized in that the spokes (80) and / or the trusses (781) and / or the segment rings (52; 552) recordings for the tensioning cables (30, 32, 34; , 132, 134, 530, 532, 534, 536, 630, 632, 634, 636, 730, 732, 830, 832, 834) and are supported by them. 12. Solar system according to one of claims 7 to 10, characterized in that the spokes (80) and / or the trusses (781) and / or the segment rings (52, 552) via cable clamps (78) on the tensioning cable trains (30, 32 , 34, 130, 132, 134, 530, 532, 534, 536, 630, 632, 634, 636, 730, 732, 830, 832, 834). 13. Solar installation according to one of claims 2 to 12, characterized in that the attachment points of the tensioning cables (30, 32, 34; 130, 132, 134; 530, 532, 534, 536; 630, 632, 634, 636; 730), 732, 830, 832, 834) to the spokes (80), the trusses (781) and the segment rings (52, 552), seen in a vertical system section, assume a lower fastening height towards the center of the installation. 14. Solar installation according to one of claims 5 to 13, characterized in that reflector modules (26-1 to 26-n) between the stabilizers (77; 577; 677; 777; 877) are mounted, wherein the reflector modules preferably (26-1 to 26-n) are provided on the edge side with coupling sections (73) via which adjacent reflector modules (26-x, 26-X + 1) can be connected directly or indirectly to one another. 15. Solar installation according to claim 14, characterized in that the reflector modules (26-1 to 26-n) in an extension (LAE) of the tensioning cables (30, 32, 34; 130, 132, 134; 530, 532, 534, 536; 630, 632, 634, 636; 730, 732; 830, 832, 834) seen in the vertical plane have substantially the cross-sectional shape of a circular arc, wherein the circular arc is preferably designed parabolic. 16. Solar installation according to claim 14 or 15, characterized in that at least one reflector module (26-1 to 26-n) has a carrier element (72) applied mirror foil (76) or mirror coating (76), wherein the carrier element ( 72) preferably made of fiber, preferably glass fiber reinforced plastic from a essentially in parabolic form brought sheet with introduced stiffening edges. 17. Solar installation according to one of claims 2 to 16, characterized in that in a cable arrangement (30, 32, 34; 130, 132, 134; 530, 532, 534, 536; 630, 632, 634, 636; 730, 732; 830, 832, 834) is aligned by a pair of guide bodies (40; 140; 240; 340; 540; 640; 740; 840) according to the course of the sun, so that at any time in the focus of the collectors a best possible efficiency of the Photovoltaic elements (28) is achieved. 18. Solar installation according to one of claims 2 to 17, characterized in that the guide bodies (40; 140; 240; 340; 540; 640; 740; 840) have a substantially triangular symmetrical base body whose base tensioning cables (30, 32 , 34, 130, 132, 134, 530, 532, 534, 536, 630, 632, 634, 636, 730, 732, 830, 832, 834) and preferably at its geometric height a journal (648, 748, 848 ), wherein the bearing pin (648; 748; 848) is preferably in the center of gravity of the rotating components. 19. Solar system according to one of claims 2 to 17, characterized in that the guide body (840) in a 0 ° position of the reflector module assembly (26) have a substantially horizontal profile whose elongated extension accommodates tensioning cables (830, 832, 834) arranged at both end regions and centrally between the end regions and has a connection (899) to the bearing journal (848) in the middle region, which has the pivot point of Guide body (840) forms. 20. Solar system according to claim 19, characterized in that a column (649, 749, 849), the bearing pin (648, 748, 849), preferably in a rolling bearing, receives and the solar system to the ground spaced. 21. Solar installation according to one of claims 2 to 20, characterized in that selected guide bodies (40; 140; 240; 340; 540; 640; 740; 840) can be driven synchronously by means of a drive device (84), wherein as drive device (84) both an electric drive, preferably with sun control and a hydraulic drive, preferably with time-dependent tracking is applicable. 22. Solar installation according to one of claims 1 to 21, characterized in that the system fulcrum of the solar system is located in the center of the rotating components. 23. Solar system according to one of claims 1 to 21, characterized in that the system fulcrum of the solar system lies in the center of gravity of the rotating components. 24. Solar system according to one of claims 2 to 23, characterized in that the substantially arranged in the focus of the reflector module arrangement energy converter assembly (24) from at least two photovoltaic elements (28) is formed, wherein the photovoltaic elements are aligned convex to the reflector module assembly (26) out , 25. A method for tracking a solar system, in particular according to one of claims 1 to 24, characterized in that in a cable arrangement (30, 32, 34; 130, 132, 134; 530, 532, 534, 536; 630, 632, 634, 636, 730, 732, 830, 832, 834) is aligned by a pair of guide bodies (40; 140; 240; 340; 540; 640; 740; 840) according to the course of the sun, so that at all times In the focus of the collectors the best possible efficiency of the photovoltaic elements (28) is achieved. 26. Reflector module (26-1 to 26-n), in particular for a solar system according to one of claims 1 to 24, with a carrier element (72) which has substantially the shape of a parabolic trough and inside a mirror coating, mirror foil or mirror surface (76 ), wherein the reflector modules are preferably equipped with coupling sections (73) via which adjacent reflector modules (26-1 to 26-n) can be connected directly or indirectly to one another. 27. reflector module (26-1 to 26-n) according to claim 26, characterized in that the carrier element (72) made of fiber, preferably glass fiber reinforced plastic. A stabilizer (77; 577; 677; 777; 877), in particular for a solar system according to one of Claims 1 to 24, in the form of a spoke arrangement (80), the spokes (80) converging in a region (82; 83) and at their respective other spoke ends with connection to a tensioning cable (30, 32, 34; 130, 132, 134; 530, 532, 534, 536; 630, 632, 634, 636; 730, 732; 830, 832, 834) ) are equipped. A stabilizer (77; 577; 677; 777; 877) according to claim 28, characterized in that the spokes (80) are interconnected via a segment ring (52; 552; 652; 752; 852). A stabilizer (77; 577; 677; 777; 877) according to claim 28 or 29, characterized in that a support (82; 83) for a photovoltaic element (28) is formed in the region where the spokes (80) converge is. 31. A stabilizer (777), in particular for a solar system according to one of claims 1 to 24, having a substantially horizontally extending traverse (781) which is cut by a substantially perpendicularly extending spoke (80), wherein the traverse (781) For tensioning cables (730, 732) and the spoke (80) carries with its upper end a holder (82, 83) for a photovoltaic element (28) and with the lower end the shape of the reflector module (26-1 to 26-n ) certainly. 32. Photovoltaic elements module, in particular for a solar system according to one of claims 1 to 24, characterized by one of two frontal cheeks (83) supported arrangement of a plurality of elongated and planar photovoltaic elements (28i and 28 ₂ ), which are employed at an angle to each other and on the outside carry a photovoltaic layer.