DE102010023217A1 - Arrangement of a PV generator - Google Patents

Abstract

Arrangement of a PV generator with support structures (1, 2, 3) arranged in a topological row (1, 2, 3), each of the support structures (1, 2, 3) at least two support profiles (3, 4, 5, 6) for supporting several PV modules (1.3, 2.3, 3.3), characterized in that at least one of the supporting profiles (3, 4, 5, 6) is in each of at least two successive supporting structures (1, 2, 3) metallic hollow profile (1.1, 2.1, 3.1) isolated from a ground potential (15) is or contains solid, and an isolated hollow profile (1.1. 2.1, 3.1) from each of the at least two successive support structures (1, 2, 3) of a first group (1.1, 2.1, 3.1) is assigned and the insulated hollow profiles (1.1, 2.1, 3.1) of the first group (1.1, 2.1, 3.1) are connected in series to form a first electrical main conductor (L1).

Description

The invention relates to an arrangement of a PV generator, in particular on an open space.

A typical PV generator has a plurality of electrically interconnected PV modules. Series PV modules are referred to as strings. A string usually consists of about 10 to 20 PV modules.

PV modules generate direct current. In contrast, higher-level power grids are usually based on alternating current. Therefore, to inject DC power from PV modules into a higher-level power grid, the DC power needs to be converted to AC, which requires inverters.

Each string of a PV array is connected to an inverter via a DC line, with multiple strings connected to a common inverter.

The transmission of direct current of a string to an inverter does not lead to negligible conduction losses. To minimize such line losses, it is common to provide large cable cross-sections of copper. In addition, to keep the length of the DC lines short, the inverters should be installed as close as possible to the strings. The AC power lines following the inverters are usually laid in trenches or cable ducts for protection against weather and other influences.

For large photovoltaic generators in open areas with a power of several megawatts, therefore, a carefully planned compromise between the number of inverters, the cost of materials for the DC cabling and the expense of laying the AC cables is to be found.

PV modules are usually mounted on support profiles of support structures. Most of the PV modules of one or more strings are arranged together on such a support structure.

Out WO 2009/101096 is a PV generator known.

Out DE 10 2008 018 422 A1 is a support structure with support profiles for a PV generator known.

Out WO 2004/0174274 A2 is a fastening device for PV modules known with profile strips, are integrated in the busbars.

The object of the invention is to minimize the number of inverters or at least the cost of DC cabling for large-area PV generators with many strings.

The object of the invention is achieved with the arrangement of a PV generator specified in claim 1. The arrangement accordingly has support structures arranged in a topological row, wherein each of the support structures has at least two support profiles arranged next to one another for supporting a plurality of PV modules. It is characteristic that in each of at least two successive of the support structures of at least one of the support profiles is a metal and insulated against a ground potential hollow profile or contains. In addition, it is provided that an insulated hollow profile of each of the at least two successive support structures is assigned to a first group and the isolated hollow profiles of the first group are connected in series to form a first electrical main conductor.

The insulated hollow sections can act as an electrical conductor on the one hand and exercise a supporting function on the other hand by these are the support profiles for the PV modules or are contained in these firmly and their carrying capacity can complement this advantageous. From both electrical and structural advantage is that the cross-section of the insulated hollow profile can be large compared to conventional pliable DC cables. Thus, at comparable load capacity compared to a conventional one-piece support profile cost-effective low-loss electrical conductor available that does not need to be installed separately and can be advantageously used as a low-loss DC cabling to an inverter. In this way, inverters can be remotely mounted and grouped together so that a large-area PV generator can operate with significantly fewer, more powerful inverters. With little central inverters, the expense for graves and cable shafts is reduced.

In an advantageous embodiment of the arrangement, at least one string of PV modules connected in series with a connection pole is connected to the first main electrical conductor. Preferably, several strings of PV modules connected in series are connected in parallel with their one terminal poles to the first main electrical conductor. As a result, the first main electrical conductor is used as intended to replace DC cabling.

In a preferred embodiment it is provided that another insulated hollow profile from each of the at least two successive Support structures is associated with a second group, wherein the insulated hollow profiles of this second group are connected in series with a second electrical main conductor. Also, the second main electrical conductor can be advantageously used as a replacement for a DC cabling to an inverter.

The at least one string is preferably connected with its other terminal pole to the second electrical main conductor. In the case of multiple strings, these can be connected in parallel with their other terminal poles to the second main electrical conductor.

In a variant, it is conceivable to connect the at least one string or the plurality of strings to the ground potential, in particular the ground potential.

To protect against overvoltage from lightning strikes, it is advantageous to alternately arrange the insulated hollow profiles of the first group and the insulated hollow profiles of the second group. Thus, in a first support structure, the isolated hollow profile of the first group with respect to the row axis on the right and the insulated hollow profile of the second group in this regard can be arranged on the left and this orientation in the next support structure exactly reversed, and so on. In this way, an insensitive to lightning strikes twisted bifilar line is formed.

Preferably, the insulated hollow profiles of a group are electrically interconnected with cables and / or substantially flush with rigid connecting elements. Cables can be laid very flexible, especially if the insulated hollow profiles are arranged successively swapped. Rigid fasteners can be a cost effective and easy to install alternative to this. In any case, it is preferred if the cables and / or the rigid connecting elements are connected to the longitudinal ends of the insulated hollow profiles.

For the protection of persons, the insulated hollow profiles are preferably insulated between their longitudinal ends substantially over their entire length and all around against the ground potential. As a result, other protective measures such as fences and warnings for high voltage can be omitted.

For a particularly high load capacity, the insulated hollow sections may have a closed hollow cross-section.

In a particularly preferred embodiment, the insulated hollow profiles are positively contained in their associated support profiles in all directions transverse to the support profiles by means of insulating means. As a result, the material cross section of the inner hollow profiles can be made very large, which is both electrically and structurally advantageous. In an advantageous embodiment, this support profiles may each have an outer hollow profile, in which the insulated hollow profiles may be positively contained in all directions transverse to the support profiles by means of insulating means. The carrying capacity of the outer and inner hollow profile can complement each other here. In addition, the outer hollow profile can therefore be made less viable, as the other support profiles that do not contain an insulated hollow profile.

For safety reasons, it may be advantageous if those support profiles, which are or contain insulated hollow profiles, which are external support profiles in the support structures.

However, in order to avoid large-area conductor loops, it is preferred that those support profiles which are or contain insulated hollow profiles are the most closely spaced in the support structures. In addition, in the case of alternately exchanged hollow profiles or in the case of intersecting connections between the longitudinal ends of the insulated hollow profiles can be kept short.

For the protection of persons and equipment, at least those supporting profiles which contain insulated hollow profiles, metal on the outside and electrically connected to the ground potential, in particular the ground potential.

In a preferred embodiment, the strings are connected to the longitudinal ends of the insulated hollow sections and / or to connections between longitudinal ends of the insulated hollow sections. In this way, lateral bores or the like for producing electrical contacts can be avoided when contained in support profiles insulated hollow profiles.

It is particularly preferred if some of the PV modules of the strings are supported by those support profiles which are or contain insulated hollow profiles. As a result, the number of conventional support profiles or those that do not contain insulated hollow profiles can be reduced.

For the attachment of PV modules, it is expedient if the support profiles have holding means for the PV modules, in particular undercut fastening channels for a clamping attachment of the edges of the PV modules and / or receiving tables for inserting the edges of the PV modules. Support profiles with such receiving tables are also known by the term Einlegprofile.

In a further development of the arrangement towards a PV generator, the first electrical main conductor can be connected to a terminal pole of an inverter.

If a second electrical main conductor is provided, it is preferably connected to the other terminal pole of the inverter. In a variant, it is conceivable that the other terminal pole of the inverter is connected to the ground potential, in particular the ground potential.

Advantageously, the inverter is arranged at one end of the topological row. This makes it possible to shorten an AC line to the inverter and, if appropriate, a cable trench for this purpose.

In a preferred extension several of the aforementioned arrangements are arranged togologically star-shaped. It is advantageous if the inverters are arranged centrally. Also, AC line can be shortened.

In a particularly advantageous embodiment, it is provided that, instead of individual, a common and centrally arranged inverter is provided, to which the plurality of first electrical main conductors and / or the plurality of second electrical main conductors are connected in common.

The invention will be described in more detail with reference to drawings. It shows:

1 a schematic of an arrangement of a PV generator with three support structures in a topological series

2 a schematic of two main conductors of the arrangement according to 1

3 a side view of a conventional support profile of the support structures according to 1

4 a side view of a support profile with a contained insulated hollow profile of the support structures according to 1

5 a side view of individual parts of the support profile according to 4

6 a schematic of an arrangement of a PV generator with multiple rows of support structures according to 1 , topologically arranged in a star shape.

7 a diagram of a further arrangement of another PV generator with three support structures in a row

1 shows a schematic of an arrangement of a PV generator. The arrangement has three in a topological series 1 . 2 . 3 arranged support structures 1 . 2 . 3 on, with each of the support structures 1 . 2 . 3 four side-by-side support profiles 7 . 4 . 5 . 6 for carrying several PV modules 1.3 . 2.3 . 3.3 having. On every support structure 1 . 2 . 3 Also referred to in technical jargon as a module table are 16 PV modules 1.3 respectively. 2.3 respectively. 3.3 arranged.

It is essential that in each of the three support structures 1 . 2 . 3 two of the supporting profiles 7 . 4 . 5 . 6 a metal and against the earth potential 15 insulated hollow profile 1.1 . 2.1 . 3.1 contains firmly.

It is also envisaged that an insulated hollow profile 1.1 , 2.1 . 3.1 from each of the support structures 1 . 2 . 3 a first group is assigned and the isolated hollow sections 1.1 . 2.1 . 3.1 the first group are connected in series to a first main electrical conductor L1.

Furthermore, another insulated hollow profile from each of the three support structures is assigned to a second group, wherein the insulated hollow profiles 1.2 . 2.2 . 3.2 the second group are connected in series to a second electrical conductor L2.

It is conceivable, in particular the last supporting structure 1 only to be provided with conventional support profiles.

It can be seen further that the insulated hollow profiles 1.1 . 2.1 . 3.1 the first group and the isolated hollow sections 1.2 . 2.2 . 3.2 The second group in each support structure are arranged alternately exchanged like a twisted pair cable to minimize interference by induction.

In addition, the insulated hollow sections 1.1 . 2.1 . 3.1 the first group as well as the isolated hollow sections 1.2 . 2.2 . 3.2 the second group with each other with cables 13 electrically connected. The cables 13 are electrically connected at the longitudinal ends of the insulated hollow sections and intersect because of the aforementioned alternately exchanged arrangement of the insulated hollow sections 1.1 . 2.1 . 3.1 . 1.2 . 2.2 . 3.2

It is also essential that the support profiles 4 . 5 with the insulated hollow sections 1.1 . 2.1 . 3.1 ; 1.2 . 2.2 . 3.2 those in the support structures 1 . 2 . 3 the two most spaced support profiles 4 . 5 are. In this way, the area between the support profiles 4 . 5 kept very small, which also contributes to the minimization of interference by induction.

The structure of the supporting profiles 7 . 4 . 5 . 6 is out 3 to 5 to be recognized in detail. So shows 3 the supporting profile 6 respectively. 7 which has a conventional design without insulated hollow profile. The hollow profile 4 respectively. 5 is on the other hand constructed in three shells. It has a metal, outer hollow profile 22 in which the metal insulated hollow profile 1.1 . 2.1 . 3.1 . 1.2 . 2.2 respectively. 3.2 in all directions across the support profiles 4 respectively. 5 by means of an isolator means 21 is recorded positively. As in 5 it can be seen, is the insulator means 21 like the outer hollow profile 22 and the insulated hollow profile 1.1 . 2.1 . 3.1 . 1.2 . 2.2 respectively. 3.2 also formed as a hollow profile with a closed hollow cross-section. It is essential that the insulated hollow profile 1.1 . 2.1 . 3.1 . 1.2 . 2.2 respectively. 3.2 between its longitudinal ends is substantially full length and round against the ground potential isolated.

In 3 and 4 is also to recognize that the support profiles 7 . 4 . 5 . 6 undercut mounting channels 20 for an ordinary clamping of the edges of the PV modules 1.3 . 2.3 . 3.3 exhibit. Furthermore, it is off 3 and 4 It can be seen that both the conventional support profiles 6 . 7 as well as the supporting profiles 4 . 5 or their outer hollow profiles with the ground potential 15 are electrically connected.

In the arrangement according to 1 is also provided that the PV modules 1.3 . 2.3 . 3.3 each supporting structure are connected in series and correspondingly three strings 1.4 . 2.4 . 3.4 form. The strings 1.4 . 2.4 . 3.4 are connected in parallel with their positive terminal poles to the first main electrical conductor L1 and with their negative terminal poles in parallel to the second main electrical conductor L2. The connection of the strings 1.4 . 2.4 . 3.4 is provided at the longitudinal ends of the insulated hollow sections.

It can be seen further that the PV modules 1.3 . 2.3 . 3.3 the strings 1.4 . 2.4 . 3.4 each on one side of the support profiles 4 . 5 and on the other side of the conventional support profiles 6 . 7 be worn.

In particular 2 clearly shows, is the first main electrical conductor L1 at a positive terminal pole 17 and the second main electric conductor L2 at the negative terminal pole 18 an inverter 14 connected. The inverter 14 is located at the right end of the topological row in the drawing 1 . 2 . 3 ,

Out 6 an arrangement can be seen which consists of four topologically star-shaped arrangements according to 1 consists of a common inverter instead of four individual inverters 14 ' is provided. At the common inverter 14 ' the four first electrical skin conductors L1 'and the four second main electrical conductors are connected together.

Finally shows 7 another arrangement with three arranged in a topological series support structures 1' . 2 ' . 3 ' on which PV modules 1.3 . 2.3 . 3.3 are arranged.

The PV modules 1.3 . 2.3 . 3.3 are connected in series to strings as before. An essential difference to the arrangement according to 1 lies in the fact that only a single group of insulated hollow sections 1.1 . 2.1 . 3.1 is provided, which are connected in series with a single electrical conductor L. The strings are therefore connected in parallel with their positive terminal poles to the main electrical conductor L, whereas the strings with their other terminal poles at ground potential 15 are connected. For closing the DC circuit, the main electric conductor L is connected to the positive terminal pole 17 of the inverter 14 ' and the negative terminal pole 18 of the inverter 14 ' at ground potential 15 connected.

LIST OF REFERENCE NUMBERS

1, 1 '

Support structure (module table)

2, 2 '

Support structure (module table)

3, 3 '

Support structure (module table)

4, 5

Support profile with included, insulated hollow profile

6, 7

conventional support profile

L1

first electrical main conductor

L2

second electrical main conductor

1.1, 2.1, 3.1

insulated hollow profile, integrated in first main electrical conductor L1

2.1, 2.2, 3.2

insulated hollow profile, integrated into second main electrical conductor L2

1.3, 2.3, 3.3

PV modules

1.4, 2.4, 3.4

String of 16 PV modules

13

Connection between insulated hollow profiles

14

inverter

14 '

common inverter

15

Ground potential, earth potential

17

Connection pole (+) at the inverter

18

Connection pole (-) on the inverter

19

AC line

20

Both sides undercut mounting channel

21

Insulator means (hollow profile)

22

outer hollow profile

QUOTES INCLUDE IN THE DESCRIPTION

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

Cited patent literature

• WO 2009/101096 [0008]
• DE 102008018422 A1 [0009]
• WO 2004/0174274 A2 [0010]

Claims (25)

Arrangement of a PV generator with in a topological series ( 1 . 2 . 3 ) supporting structures ( 1 . 2 . 3 ), each of the support structures ( 1 . 2 . 3 ) at least two juxtaposed support profiles ( 3 . 4 . 5 . 6 ) for carrying several PV modules ( 1.3 . 2.3 . 3.3 ), characterized in that in each of at least two consecutive of the support structures ( 1 . 2 . 3 ) at least one of the support profiles ( 3 . 4 . 5 . 6 ) a metal and against a ground potential ( 15 ) insulated hollow profile ( 1.1 . 2.1 . 3.1 ) or solid, and an insulated hollow profile ( 1.1 , 2.1 . 3.1 ) from each of the at least two consecutive support structures ( 1 . 2 . 3 ) of a first group ( 1.1 . 2.1 . 3.1 ) and the isolated hollow profiles ( 1.1 . 2.1 . 3.1 ) of the first group ( 1.1 . 2.1 . 3.1 ) are connected in series with a first main electrical conductor (L1). Arrangement according to claim 1, that at least one string ( 1.4 ) of series-connected PV modules ( 1.3 ) is connected to a terminal pole on the first main electrical conductor (L1). Arrangement according to claim 1, characterized in that several strings ( 1.4 . 2.4 . 3.4 ) of series-connected PV modules ( 1.3 . 2.3 . 3.3 ) are connected in parallel with their one terminal poles to the first main electrical conductor (L1). Arrangement according to one of claims 2 to 3, characterized in that another insulated hollow profile ( 1.2 . 2.2 . 3.2 ) from each of the at least two consecutive support structures ( 1 . 2 . 3 ) of a second group ( 1.2 . 2.2 . 3.2 ), and the isolated hollow profiles ( 1.2 . 2.2 . 3.2 ) of the second group ( 1.2 . 2.2 . 3.2 ) are connected in series to a second main electrical conductor (L2). Arrangement according to claim 2 and 4, that the at least one string ( 1.4 ) is connected with its other terminal pole to the second main electrical conductor (L2) or at ground potential ( 15 ) connected. Arrangement according to Claims 3 and 4, characterized in that the strings ( 1.4 . 2.4 . 3.4 ) are connected in parallel with their other connecting poles to the second electrical main conductor (L2) or at ground potential ( 15 ) are connected. Arrangement according to one of claims 4 to 6, characterized in that the insulated hollow profiles ( 1.1 . 2.1 . 3.1 ) of the first group ( 1.1 . 2.1 . 3.1 ) and the isolated hollow profiles ( 1.2 . 2.2 . 3.2 ) of the second group ( 1.2 . 2.2 . 3.2 ) are arranged alternately swapped. Arrangement according to one of claims 1 to 7, characterized in that the insulated hollow profiles ( 1.1 . 2.1 . 3.1 ; 1.2 . 2.2 . 3.2 ) of a group ( 1.1 . 2.1 . 3.1 ; 1.2 . 2.2 . 3.2 ) with each other with cables ( 13 ) and / or substantially in alignment with rigid connecting elements are electrically connected. Arrangement according to one of claims 1 to 8, characterized in that the insulated hollow profiles ( 1.1 . 2.1 . 3.1 ; 1.2 . 2.2 . 3.2 ) between their longitudinal ends substantially over their entire length and all around against the ground potential ( 15 ) are isolated. Arrangement according to one of claims 1 to 9, characterized in that the insulated hollow profiles ( 1.1 . 2.1 . 3.1 ; 1.2 . 2.2 . 3.2 ) have a closed hollow cross-section. Arrangement according to one of claims 1 to 10, characterized in that the insulated hollow profiles ( 1.1 . 2.1 . 3.1 ; 1.2 . 2.2 . 3.2 ) in their associated support profiles ( 4 . 5 ) in all directions transverse to the supporting profiles ( 4 . 5 ) by means of an isolator ( 21 ) are positively contained. Arrangement according to the preceding claim, characterized in that these support profiles ( 4 . 5 ) each an outer hollow profile ( 22 ) in which the isolated hollow profiles ( 1.1 . 2.1 . 3.1 ; 1.2 . 2.2 . 3.2 ) in all directions transverse to the supporting profiles ( 4 . 5 ) by means of an isolator ( 21 ) are positively contained. Arrangement according to one of claims 1 to 12, characterized in that those support profiles ( 4 . 5 ), the insulated hollow sections ( 1.1 . 2.1 . 3.1 ; 1.2 . 2.2 . 3.2 ) contained in the supporting structures ( 1 . 2 . 3 ) external support profiles ( 3 . 6 ) are. Arrangement according to one of claims 1 to 13, characterized in that those support profiles ( 4 . 5 ), the isolated hollow profiles ( 1.1 . 2.1 . 3.1 ; 1.2 . 2.2 . 3.2 ) contained in the supporting structures ( 1 . 2 . 3 ) the most closely spaced support profiles ( 4 . 5 ) are. Arrangement according to one of claims 1 to 14, characterized in that those support profiles ( 4 . 5 ), the insulated hollow sections ( 1.1 . 2.1 . 3.1 ; 1.2 . 2.2 . 3.2 ), metals on the outside and with the ground potential ( 15 ) are electrically connected. Arrangement according to one of Claims 1 to 15, characterized in that the strings ( 1.4 . 2.4 . 3.4 ) at longitudinal ends of the insulated hollow sections ( 1.1 . 2.1 . 3.1 ; 1.2 . 2.2 . 3.2 ) and / or connections ( 13 ) between longitudinal ends of the insulated hollow profiles ( 1.1 . 2.1 . 3.1 ; 1.2 . 2.2 . 3.2 ) are connected. Arrangement according to one of claims 1 to 15, that some of the PV modules ( 1.3 . 2.3 . 3.3 ) of the strings ( 1.4 . 2.4 . 3.4 ) of those supporting profiles ( 4 . 5 ), the isolated hollow profiles ( 1.1 . 2.1 . 3.1 ; 1.2 . 2.2 . 3.2 ) are or are worn. Arrangement according to one of claims 1 to 17, which the support profiles ( 3 . 4 . 5 . 6 ) Holding means for the PV modules ( 1.3 . 2.3 . 3.3 ), in particular undercut fastening channels ( 20 ) for a clamp fastening of the edges of the PV modules ( 1.3 . 2.3 . 3.3 ) and / or receiving tables for inserting the edges of the PV modules. Arrangement according to one of claims 1 to 18, characterized in that the first electrical main conductor (L1) at a terminal pole ( 17 ) of an inverter ( 14 ) connected. Arrangement according to claim 18, characterized in that the second electrical main conductor (L2) is connected to the other terminal pole (L2). 18 ) of the inverter ( 14 ) connected. Arrangement according to claim 18, characterized in that the other terminal pole ( 18 ) of the inverter ( 14 ) is connected to earth potential. Arrangement according to one of claims 18 to 21, characterized in that the inverter ( 14 ) at one end of the topological series ( 1 . 2 . 3 ) is arranged. Arrangement with a plurality of topologically star-shaped arrangements according to one of Claims 1 to 22. Arrangement according to claim 23, characterized in that the inverters ( 14 ) are arranged centrally. Arrangement according to claim 23, characterized in that a common and centrally arranged inverter ( 14 ' ) is provided, to which the plurality of first main electrical conductors (L1) and / or the plurality of second main electrical conductors (L2) are connected in common.

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