DESC:Field of invention

The present invention relates to a mounting structure, particularly, the present invention relates to a module mounting structure for mounting or holding a photo-voltaic (solar) module or photo-voltaic panel on ground for a large size solar energy based power generation plant.

Background of the Invention

Module mounting structure is used for mounting plurality of interconnected solar modules in a Photo-Voltaic (PV) power plant. The module mounting structure comprises components like vertical columns, rafters/beams, purlins and accessories like fasteners (i.e. nut-bolt). These components of the module mounting structure are made of material like Aluminum, Mild steel concrete etc. to withstand prevailing wind force conditions in the installation area with maintenance free life of more than 10 years.

In a sample case of a 1 Mw plant made up of crystalline technology using 290Wp Modules, the total number of parts / components are approximately 30,000 numbers divided into 25~40 types. These components need to be designed, procured, fabricated, transported, segregated and assembled at the site or location of the solar power generation plant to construct the module mounting structure. The process of assembling the components to construct the module mounting structure is sequence oriented and cumbersome from erection point of view. The approximate cost for the good quality robust, Indian standard complied traditional construct the module mounting structure is generally 45~50Lacs/Mw for a module with crystalline technology.

In the existing mounting structures, solar panels/modules are being mounted on the ground in large scale on mounting structures supporting the panels in an array. It is important that these structures should be such designed that it can be easily erected at site or location of the solar power plant, since due to large number and large types of components in the module mounting structure makes the erection sequence cumbersome thereby resulting in increase in erection time, misalignment and also requirement of special training to the unskilled labors. Since, the mounting structure includes large number of components and therefore these components are to be sequentially numbered with a special marking scheme corresponding to their sequence in the assembly process. Further, the tolerances required in such erections are transferred to the solar panel making it difficult to achieve the desired accuracy.

Therefore, there exists a need to develop a module mounting structure which overcome or at least reduces the effect of the problems associated with the existing module mounting structure.

Summary of invention:

The present invention provides a module mounting structure for mounting photo volatic (PV) panel. The module mounting structure of the present invention comprises a plurality of vertically extending columns having a top end and bottom end; and a plurality of beams secured to the columns and being disposed substantially parallel to each other. Each of the beams is secured to the respective column so as to extend in a lateral direction. The structure of the present invention comprises a plurality of arrays of purlins secured to the beams and being disposed substantially parallel to each other so as to form a grid for mounting the photo-volatic (PV) panel. Each of the said array comprises a plurality of purlins extending in a longitudinal direction; and a plurality of connecting members for securing the end of the purlins with end of the adjacent purlin and for securing the array of the purlins with the beams. Each of the connecting members is formed so as to allow the linear adjustments between the ends of the purlins in the longitudinal direction and to allow the linear adjustments of the array of purlins with respect to the beam in the longitudinal direction.

Brief description of figures:

Figure 1 is an exemplary illustration of the module mounting structure according to an embodiment of the present invention.
Figure 2 illustrates partial view of the module mounting structure showing intermediate columns of the module mounting structure shown in Figure 1.
Figure 3 illustrates a partial view of the module mounting structure showing end columns of the module mounting structure shown in Figure 1.
Figure 4 illustrates connection between the column and the rafter of the module mounting structure according to an embodiment of the present invention.
Figure 5 illustrates connection between the column and the bracing of the module mounting structure according to an embodiment of the present invention.
Figure 6 illustrates connection member for connecting the purlins with each other and with the beam of the module mounting structure according to an embodiment of the present invention.

Detailed description of the present invention:

While the invention is susceptible to various modifications and alternative forms, specific embodiment thereof has been shown by way of example in the figures and will be described in detail below. It should be understood, however that it is not intended to limit the invention to the particular forms disclosed, but on the contrary, the invention is to cover all modifications, equivalents, and alternative falling within the spirit and the scope of the invention as defined by the appended claims.

Before describing in detail the various embodiments of the present invention it may be observed that the novelty and inventive step that are in accordance with the present invention resides in the construction of module mounting structure. It is to be noted that a person skilled in the art can be motivated from the present invention and modify the various constructions of module mounting structure. However, such modification should be construed within the scope and spirit of the invention.

Accordingly, the drawings are showing only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having benefit of the description herein.

The terms “comprises”, “comprising”, “including” or any other variations thereof, are intended to cover a non-exclusive inclusion, such that an assembly, mechanism, setup, that comprises a list of components does not include only those components but may include other components not expressly listed or inherent to such assembly, mechanism or setup. In other words, one or more elements in module mounting structure or assembly proceeded by “comprises a” does not, without more constraints, preclude the existence of other elements or additional elements in the assembly or mechanism. The following paragraphs explain present invention and the same may be deduced accordingly.

Accordingly, the present invention provides a module mounting structure for mounting photo-volatic (PV) panel, comprising
(a) a plurality of vertically extending columns having a top end and bottom end;
(b) a plurality of beams secured to the columns and being disposed substantially parallel to each other; each of the beam is secured to the respective column so as to extend in a lateral direction;
(c) a plurality of arrays of purlins secured to the beams and being disposed substantially parallel to each other so as to form a grid for mounting the photo-volatic (PV) panel; each of the said array comprises:
(i) a plurality of purlins extending in a longitudinal direction; and
(ii) a plurality of connecting members for securing the end of the purlins with end of the adjacent purlin and for securing the array of the purlins with the beams; each of the connecting member is formed so as to allow the linear adjustments between the ends of the purlins in the longitudinal direction and to allow the linear adjustments of the array of purlins with respect to the beam in the longitudinal direction.

In an embodiment of the present invention, the beam are secured with the columns so as to form a predetermined angle with respect to the respective columns.

In another embodiment of the present invention, the beam is provided with elongated slots and the column is provided with respective holes for securing the beam with the column using fasteners.

In still another embodiment of the present invention, the connecting member having:
a first plate, and
a second plate which is contiguous and orthogonal to the first plate;
the first plate is provided with one or more elongated slots to cooperate with corresponding holes disposed at the ends of the purlins for securing the ends of adjacent purlins using the fasteners to form the array of purlins and so as to accommodate linear adjustment between the ends of adjacent purlins in the longitudinal direction;
the second plate is provided with at least one elongated slot to cooperate with a corresponding hole disposed on the beam for securing the purlin or the array of purlin with the beam using fasteners so as to accommodate linear adjustments between the array of purlins and the beam in the longitudinal direction;

In yet another embodiment of the present invention, each of the column is mounted on ground using a base plate secured at the bottom end of each of the column.

In a further embodiment of the present invention, the base plate is rigidly secured with the column and the base plate is provided with elongated slots so as to allow the linear adjustment of the base plate in lateral direction or in linear direction.

In a further more embodiment of the present invention, the columns and the respective beam are supported by a bracing having two opposite ends in which one end is secured with the beam and other end is secured to the column.

In an embodiment of the present invention, each of the columns has a C-shape cross section formed by a base portion and a two flange portion extending perpendicularly from edges of the base potion.

In another embodiment of the present invention, each of the columns is provided with auxiliary holes on the flange portions and proximal to the top end and bottom ends for connecting a cross member between the two adjacent columns.

In one more embodiment of the present invention, the each of the beams and purlins is having a C-shape cross section without or with lip, respectively.

Accordingly, it is an aim of the present invention to provide a module mounting structure which reduces the number of different types of the parts required in module mounting structure. Another aim of the present invention is provide a module mounting structure which accommodates the misalignment and allow the adjustments in one or more directions.

The following paragraphs describe the module mounting structure of the present invention with reference to figures 1-6.

Figure 1 illustrates a module mounting structure (1) for mounting or supporting photo-voltaic (PV) panel (not shown in Figures) according to an embodiment of the present invention. The term ‘photo-voltaic panel’ herein refers to a solar module or plurality of interconnected solar modules used for generating electricity by solar energy in a solar power plant. The term ‘module’ herein refers to one solar module or plurality of interconnected modules.

As shown in Figure 1, module mounting structure (1) comprises a plurality of vertically extending columns (2) and a plurality of beams (3) secured to the columns (2). Each of the beams (3) is secured to one of the plurality of columns (2). The each beam (3) is secured to the column (2) so as to extend in a lateral direction. The beams (3) are disposed substantially parallel to each other. In other words, when the beams (3) are secured with the respective columns (2), each of the beams (3) remains substantially parallel with respect to the other beam. A plurality of arrays (4) of purlins (5) secured to the beams (3). Each array (4) of purlins extends in longitudinal direction and formed by plurality of purlins (5) with their ends placed side by side or facing each other. In other words, the array of purlins (4) is formed by placing the plurality of purlins (5) so that the longitudinal axis of the each purlin is in alignment with the longitudinal axis of the other purlin (4). The term ‘array’ herein refers to a set or group comprises plurality of similar elements such as purlins.

Plurality of such arrays (4) of purlins is secured to the beam (3) and each array (4) is disposed on the beams (5) substantially parallel to the other arrays (4) of purlins thereby forming a grid for mounting the photo-volatic (PV) panel (not shown in Figures).

The purlins (4) can be secured using connecting members (6) (as shown in Figures 2, 3 and 6). Accordingly, a plurality of connecting members (6) may be used for securing the ends of the purlins (5) with the ends of the adjacent purlin and with the beams (4). Each of the connecting member (6) is formed so as to allow the linear adjustments between the ends of the purlins (5) in the longitudinal direction and to allow the linear adjustments of the array (4) of purlins with respect to the beam (3) in the longitudinal direction.

Referring to Figures 2, 3 and 5, each of the columns (2) is an elongated and vertically extending post or pillar having a top end (2a) and a bottom end (2b). The bottom end (2b) of the each of the column (2) may be mounted on the ground. For this purpose a foundation may be formed on the ground and the column may be mounted on the foundation with the help of a base plate (BP) (7) and stiffeners (Gussets). The module mounting structure of the present invention can be mounted / installed in any suitable types of foundation system selected from the group comprising but not limited to Pile foundation, Open/ isolated footing, Rock Anchoring , Foundation and Beams, Ramming.

The base plate (7) may be rigidly secured (for example by welding) at the bottom end (2b) of the column (2). The base plate (7) may be provided with slotted holes (Sc) and the foundation may be provided with corresponding holes to cooperate with the slotted holes (Sc) formed in the base plate (7), for securing the base plate (7) with the foundation using fasteners. The term ‘slotted hole’ herein refers to a hole which is elongated as opposed to circular. The slotted holes (Sc) provide flexibility for alignment and for maintaining center to center distance/spacing between the columns (2). In other words, the elongated slots (Sc) allow the linear adjustment of the base plate in lateral direction. For securing the base plate of column on the foundation, a foundation-plate (not shown in Figures) can be mounted on the foundation and the base plate (7) may be secured to the foundation plate for mounting the mounting the columns (2). The foundation plate can be provided with slotted holes extending in longitudinal direction so as to allow linear adjustments of the base plate in the longitudinal direction. Alternatively, the slotted holes of the base plate may be formed to extend in longitudinal direction to allow linear adjustments of the base plate in the longitudinal direction, and the slotted holes of the foundation plate may be formed to extend in lateral direction to allow linear adjustments of the base plate in the lateral direction.

In an embodiment, the columns (2) may be constructed so that they are inter-changeable. The columns may be made of any suitable materials and of any suitable cross section. In an embodiment, the columns may be made from structural steel fabricated from HR (Hot Rolled) coils and cross-section of the columns may be of C shape.

Referring to Figures 2, 3 and 4, the rafter or beam (3) is an elongated and rigid member having two opposite ends (3a, 3b). The rafters or beams (3) may be secured to the columns (2), at or near the top end (2a) of the columns (2) using fasteners. For this purpose, each of the beams (3) is provided with slotted holes (Sb) (i.e. holes in the form of elongated slots) and corresponding holes (H) may be formed in the column (2) near its top end (2a) for cooperating with the fasteners and the slotted holes (Sb) of the beam (3) for securing the beam (3) with the column (2). As can be understood from Figures 2, 3 and 4, the beams (3), when secured with the respective columns (2), extend in lateral direction. The term ‘lateral direction’ herein refers to a direction perpendicular to the vertical direction in which the columns (2) extend and perpendicular to the longitudinal direction in which the purlins (5) extend.

The slotted holes (Sb) of the beams (3) and corresponding holes (H) in the columns (2) may be formed so that the beams (3) can be secured to the respective column (2) at a predetermined angular position. The said angle between the beams and the respective columns may be determined based on the coordinates (longitude and latitude) of the location at which the Solar PV plant is to be installed. In an embodiment, the beams are secured at predetermined angle with respect to the respective beams including an adjustment of angle in the range of ± 2o.

As shown in Figure 4, each of the columns has a C-shape cross section formed by a base portion (2c) and a two flange portion (2d) extending perpendicularly from edges of the base potion (2c). The base portion (2c) of the C-shape cross section of the column (2) is provided with the holes (H) disposed at or near the top end (2a) of the columns (2). The said holes (H) are formed to cooperate with the slotted holes (Sb) of the beams (3) for securing the beams (3) with the respective columns (2). The slotted holes (Sb) in the beams (3) provide flexibility in aligning the beam (3) in lateral direction, and fixing the beams (3) at the desired tilt angle. In other words, the slotted holes (Sb) on the beam allow linear adjustments of the beam (3) in the lateral direction with respect to the respective column (2). In an embodiment, the beams (3) may also be constructed in such a manner that they are inter-changeable. The rafters or beams (3) may be made of any suitable material and cross section. In an embodiment, the rafters or beams are made of structural steel fabricated from HR coils and cross-section of the beams may be of C shape without a lip.

Referring to figures 2, 3 and 5, a plurality of elongated bracings (8) is provided in the module mounting structure for transferring the wind-force from the beam (3) to the column (2). The bracing (8) is an elongated and rigid member having two opposite ends. Each of the bracing (8) is secured between the beam (3) and the column (2) to which the said beam (3) is secured. One end of the bracing (8) may be secured to the beam (3) at an intermediate location between the two opposite ends (3a, 3b) of the beam (3); while other end of the bracing (83) is secured near the bottom end (2b) of the column (2s). As can be clearly observed from figures 2 and 3, the bracing (8) are to be secured at an angular position with respect to the vertically extending column (2). For this purpose, angle cleats or connection plates (9) may be used for securing the bracing (8) with the column (2) near its bottom end (2b). The bracing (8) may be made of any suitable material and cross section. In an embodiment, the bracing may be made of HR coil steel and formed to have an angle cross-section.

Referring to Figures 1, 2, 3 and 6, a plurality of longitudinally extending purlins (5) each having two opposite ends, a first end (5a) and a second end (5b), are secured to the beams (3). Referring to figure 1, the module mounting structure (1) requires large longitudinal dimension than the lateral dimension. As can be clearly observed from figures 1-3, the lateral dimension of the module mounting structure (1) may be defined by the length of a beam (3). However, the longitudinal dimension of the module mounting structure (1) may be defined by the cumulative length of the plurality of purlins (5) placed side by side. In other words, to achieve the large longitudinal dimension of the module mounting structure (1), a plurality of purlins (5) is required with their longitudinal axis in substantial alignment with the other purlins. As shown in figure 1, lateral dimension of the module mounting structure (1) can be formed by length of single beam (3) whereas, longitudinal dimension of the module mounting structure (1) is formed by cumulative length of the plurality of purlins (5) placed in axial alignment with each other thereby forming an array (4) of purlins. Similarly, plurality of such arrays (4) of purlins may be secured on to the beams (3) and disposed parallel to each other so as to form a grid on the beams (3) for mounting or supporting the solar panel or module (not shown in Figures) on the module mounting structure (1).

The purlins may be made of any suitable material and cross section. In an embodiment, the purlins are made of structural steel fabricated from HR coils and cross-section of the beams may be of C shape with a lip.

For securing the array (4) of purlins with the beam, the beams (3) and the purlins (5) may be provided with holes which are adapted to cooperate with the fasteners for securing the purlins with the beams. Photo-Voltaic (PV) or solar panel modules are directly secured or supported on the parallel arrangement of the arrays of purlins.

Since, the longitudinal dimension of the module mounting structure require placing the large number of purlins in axial alignment each other thereby forming longitudinally extending array of purlins, and securing the said array of purlins require holes of the purlins and the corresponding holes of the beams are in alignment with each other. If there is any misalignment, the assembly of the module mounting structure would be cumbersome and difficult or not possible. Therefore, in an embodiment of the present invention, a plurality of connection members are provided for securing the longitudinally extending arrays of purlins with the laterally extending beams.

Referring figure 6, the connection member can be in the form of bracket which comprises a first plate (6a), and a second plate (6b) orthogonal and contiguous to the first plate (6a). The first plate (6a) is provided with one or more elongated slots or slotted holes (Sp) to cooperate with corresponding holes disposed at the ends (5a, 5b) of the purlins (5) for securing the ends of adjacent purlins (5) using fasteners to form the array of purlins. As shown in Figures 2, 3 and 6, end of the purlins disposed at ends of the module mounting structure (1) in longitudinal direction are secured to the beam (3) with by means of the connecting member (6). The elongated slots (Sp) formed on the first plate (6a) allow linear adjustment between the ends of adjacent purlins in the longitudinal direction. The second plate (6b) of the connection member (6) is provided with at least one elongated slot (Sp) to cooperate with a corresponding hole disposed on the beam (3) for securing the purlin (5) or the array (4) of purlin with the beam (3) using fasteners. The elongated slot (Sb) formed on the second plate (6b) allows linear adjustments between the array (4) of purlins and the beam (3) in the longitudinal direction.

The first plate (6a) is provided with plurality of slotted holes (i.e. holes in the form of elongated slots) (Sb) and corresponding holes are provided at or near the ends (5a, 5b) of the purlins (5), which are adapted to cooperate with the fasteners for securing the purlins in axial alignment with each other thereby forming an array (4) of purlins (5). The second plate (6b) is provided one slotted hole and the corresponding hole is provided with beam, which are adapted to cooperate with the fasteners for securing the purlins (5) with the beam (3). The connecting member (6) allows two stages of the linear adjustments, first stage include adjustment between the spacing between the ends of two adjacent purlins in the longitudinal direction in an array of purlins and second stage includes adjustments with respect to the alignment of the slotted hole in the second plate of the connecting member and the corresponding hole formed on the beam for securing the array (4) of purlins with the beam (3). This construction makes the purlins interchangeable and there is no need to sequentially number the purlins. Further, this construction ensures easy installment and maintain alignment of modules.

Referring to Figure 3, in the module mounting structure (1), end columns (2) (i.e. columns disposed at the ends of the module mounting structure (1) in longitudinal direction) are to be secured with a cross-member (10) for providing stability. As shown in Figure 3, end columns (2e, 2e’) are provided with a rigid cross member (10), which is secured between the two end columns (2e, 2e’) toward one of the end the module mounting structure (1) in longitudinal direction. In other words, the end column (2e) and second column (2e’) from the said end column (2e) are secured with a cross member (10). Similarly, at the other end of the module mounting structure the end column and second column from the said end column are secured with a cross member. For this purpose, end columns are required to be provided with additional holes for securing the cross-member with the end columns and second last columns from the said end column. Therefore, the columns are to be marked or numbered as end columns to be placed at the location of end columns and not at any other location.

In an embodiment of the invention, each of the plurality of columns is provided with additional holes so that any column can qualify to be used as end column and second last columns from the said end. In other words, there is no requirement of marking any column as end columns, second last column or intermediate column.

Some of the advantages of the module mounting structure of the present invention are as follows:

1. Robust designed structure able to withstand designed wind pressure.
2. Design complied with Indian standards and codes.
3. Structure Fabricated from hot rolled coil.
4. Minimum thickness of sheet used as 2mm.
5. Post fabricated 80 micron galvanizing done.
6. Maintenance free life more than 10years
7. Components are interchangeable and reduced to as low as 10 types.
8. Easy in handling and transportation
9. Erection friendly
10. Faster execution
11. Cost reduction by approximately 25%
,CLAIMS:A module mounting structure for mounting photo-volatic (PV) panel, comprising
(a) a plurality of vertically extending columns having a top end and bottom end;
(b) a plurality of beams secured to the columns and being disposed substantially parallel to each other; each of the beam is secured to the respective column so as to extend in a lateral direction;
(c) a plurality of arrays of purlins secured to the beams and being disposed substantially parallel to each other so as to form a grid for mounting the photo-volatic (PV) panel; each of the said array comprises:
(i) a plurality of purlins extending in a longitudinal direction; and
(ii) a plurality of connecting members for securing the end of the purlins with end of the adjacent purlin and for securing the array of the purlins with the beams; each of the connecting member is formed so as to allow the linear adjustments between the ends of the purlins in the longitudinal direction and to allow the linear adjustments of the array of purlins with respect to the beam in the longitudinal direction.

2. The module mounting structure as claimed in claim 1, wherein the beam are secured with the columns so as to form a predetermined angle with respect to the respective columns.

3. The module mounting structure as claimed in claim 1, wherein the beam is provided with elongated slots and the column is provided with respective holes for securing the beam with the column using fasteners.

4. The module mounting structure as claimed in claim 1, wherein the connecting member having:
a first plate, and
a second plate which is contiguous and orthogonal to the first plate;
the first plate is provided with one or more elongated slots to cooperate with corresponding holes disposed at the ends of the purlins for securing the ends of adjacent purlins using the fasteners to form the array of purlins and so as to accommodate linear adjustment between the ends of adjacent purlins in the longitudinal direction;
the second plate is provided with at least one elongated slot to cooperate with a corresponding hole disposed on the beam for securing the purlin or the array of purlin with the beam using fasteners so as to accommodate linear adjustments between the array of purlins and the beam in the longitudinal direction;

5. The module mounting structure as claimed in claim 1, wherein each of the column is mounted on ground using a base plate secured at the bottom end of each of the column.

6. The module mounting structure as claimed in claim 1, wherein the base plate is rigidly secured with the column and the base plate is provided with elongated slots so as to allow the linear adjustment of the base plate in lateral direction or longitudinal direction.

7. The module mounting structure as claimed in claim 1, wherein the columns and the respective beam are supported by a bracing having two opposite ends in which one end is secured with the beam and other end is secured to the column.

8. The module mounting structure as claimed in claim 1, wherein each of the columns has a C-shape cross section formed by a base portion and a two flange portion extending perpendicularly from edges of the base potion.

9. The module mounting structure as claimed in claims 1 and 8, wherein each of the columns is provided with auxiliary holes on the flange portions and proximal to the top end and bottom ends for connecting a cross member between the two adjacent columns.

10. The module mounting structure as claimed in claim 1, wherein the each of the beams and purlins is having a C-shape cross section without or with lip, respectively.