DESC:FIELD OF THE INVENTION
The present invention generally relates to the field of solar PV plants. More particularly, the present invention relates to retro-fitment of reflectors in solar PV plants.

BACKGROUND OF THE INVENTION
It is known that solar PV plants are configured for generating electricity from solar energy. Solar PV plants comprises of a plurality of PV blocks for generating electricity from solar energy. Each PV block comprises of a plurality of PV arrays including PV modules which are coupled to inverters, step up transformers and circuit breakers, etc. More specifically, the DC power generated by PV modules is converted to AC power using inverters. The generated AC power is stepped up using step up transformers and finally fed to grid for commercial use via circuit breakers.
Further, it is known that as the sun moves up and down in the south sky as the seasons change, the output of solar PV plants change with the angle of the sun. Solar PV plants produce the most energy when the sunlight is hitting them directly. In other words, the efficiency of a solar PV plant mainly depends on the amount of sunlight falling on the PV modules. Thus, in order to enhance the efficiency of solar PV plants it is necessary to increase the amount of light incident on the PV modules.
Various efforts have been made to increase the amount of light incident on the PV modules. Some efforts include use of tracking system to track the position of the sun and change the angle of inclination/alignment of the PV modules accordingly so that maximum light can be received by the PV modules. Tracking system used may be single axis or dual axis tracking system. However, some of the said systems (like CPV) require complex shaping and forming of optical elements to reflect light on the PV modules. All commercial tracking systems generally require motorized mechanisms to adjust the tilt and/or azimuth angles of the PV modules to track the sun so as to maximize the incident solar radiation.

Another approach is the use of reflectors in solar PV plants. The reflectors in a solar PV plant are usually installed at different positions with respect to the position of the PV modules. For instance, reflectors are installed at either top or bottom or left or right of the PV modules.

The configuration where the reflectors are installed at the left or right of the PV modules requires the distance between two PV arrays to be increased. The increase in the distance between two PV arrays leads to an increase in the length of the cables used to connect the PV modules to the inverters. Due to an increase in the cable length, cable losses increases. Moreover, the increase in distance between two PV arrays increases the land requirement where the PV arrays are installed thereby increasing the installation cost of the solar PV plants.

The configuration where the reflectors are installed at the top or bottom of the PV modules also suffers from a number of disadvantages. The installation of reflectors on the top of PV modules causes shading effect on the next/adjacent row of PV arrays. Thus, in order to minimize the shading effect, distance between every two adjacent rows of the PV arrays has to be increased which again increases the land requirement where the PV arrays are installed thereby increasing the installation cost of the solar PV plants. Further, the configuration where the reflectors are installed at the bottom position suffers from inadequate reflection.

The use of reflectors usually requires a separate support structure/frame to install the reflectors on the left or right or top or bottom of the PV modules. A disadvantage of this configuration is that the support structure/frame for the reflectors has to be designed according to the support structure/frame used for supporting the PV modules. This results in an increase in the complexity of the support structure/frame used for supporting the reflectors. Also, it increases the installation cost of the solar PV plants.

Therefore, there exists a need in the art to provide a technique which overcomes the above mentioned disadvantages and at the same time enhances the efficiency of solar PV plants.

OBJECTS OF THE INVENTION
The principal object of the present invention is the retro-fitment of reflectors in solar PV plants.

SUMMARY OF THE INVENTION
Accordingly, the present invention relates to a reflector unit capable of being retrofitted to a pre-installed solar PV unit, the solar PV unit including a mounting element; a solar PV module fixed over the mounting element; and a vertical member, said mounting element being fixed over the vertical member in an inclined position, the reflector unit comprising: a first member; a reflector module mounted over the first member, said first member being coupled to the mounting element such that the reflector module is positioned behind the solar PV module; and a supporting element provided between the vertical member and the first member for supporting the first member at an angular position with respect to a horizontal plane; wherein the supporting element is configured to vary the angular position of the first member with respect to the horizontal plane; and wherein the said angular position is varied by varying length L of the supporting element.
Also, the present invention relates to a reflector unit capable of being retrofitted to a pre-installed solar PV array, the solar PV array including a mounting element having first and second ends; a plurality of solar PV modules longitudinally spaced apart and fixed over the mounting element thereby forming the PV array; and first and second vertical members positioned on first and second ends of the mounting element, said mounting element being fixed over the vertical members in an inclined position, the reflector unit comprising: a first member having first and second ends; a reflector module mounted over the first member, said first member being coupled to the mounting element such that the reflector module is positioned behind the plurality of solar PV modules; a first supporting element provided between the first vertical member and the first member; and a second supporting element provided between the second vertical pillar and the first member; wherein the first and second supporting elements are configured for supporting the first member at an angular position with respect to a horizontal plane; wherein the first and second supporting elements are configured to vary the angular position of the first member with respect to the horizontal plane; and wherein the said angular position is varied by varying length L of the supporting elements.

In the above paragraphs the most important features of the invention have been outlined, in order that the detailed description thereof that follows may be better understood and in order that the present contribution to the art may be better understood and in order that the present contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be described hereinafter and which will form the subject of the claims appended hereto. Those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for the designing of other structures for carrying out the several purposes of the invention. It is important therefore that the claims be regarded as including such equivalent constructions as do not depart from the spirit and scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
Further aspects and advantages of the present invention will be readily understood from the following detailed description with reference to the accompanying drawings, where like reference numerals refer to identical or functionally similar elements throughout the separate views. The figures together with the detailed description below, are incorporated in and form part of the specification, and serve to further illustrate the aspects and explain various principles and advantages, in accordance with the present invention wherein:
Figures 1a and 1b show the retro-fitment of a reflector unit to a pre-installed solar PV unit according to an embodiment of the present invention;

Figure 1c shows the retro-fitment of a reflector unit to a pre-installed solar PV unit according to another embodiment of the present invention;

Figure 2a shows the variation in the angular position of the reflector according to an embodiment of the present invention;

Figure 2b shows the variation in the angular position of the reflector according to another embodiment of the present invention; and

Figure 3 shows the energy generation report in a solar PV plant.

Skilled artisans will appreciate that elements in the drawings are illustrated for simplicity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the drawings may be exaggerated relative to other elements to help to improve understanding of the aspects of the present invention.

DETAILED DESCRIPTION OF THE INVENTION
In order that the invention may be readily understood and put into practical effect, reference will now be made to exemplary embodiments as illustrated with reference to the accompanying drawings. The figures together with a detailed description below, are incorporated in and form part of the specification, and serve to further illustrate the embodiments and explain various principles and advantages.
The terms “comprises”, “comprising”, or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method that comprises a list of steps does not include only those steps but may include other steps not expressly listed or inherent to such process, method. Similarly, one or more elements in a system or apparatus or device proceeded by “comprises” does not, without more constraints, preclude the existence of other elements or additional elements in the system or apparatus or device.

According to an aspect, the present invention relates to a reflector unit capable of being retrofitted to a pre-installed solar PV unit, the solar PV unit including a mounting element; a solar PV module fixed over the mounting element; and a vertical member, said mounting element being fixed over the vertical member in an inclined position, the reflector unit comprising: a first member; a reflector module mounted over the first member, said first member being coupled to the mounting element such that the reflector module is positioned behind the solar PV module; and a supporting element provided between the vertical member and the first member for supporting the first member at an angular position with respect to a horizontal plane; wherein the supporting element is configured to vary the angular position of the first member with respect to the horizontal plane; and wherein the said angular position is varied by varying length L of the supporting element.

According to another aspect, the present invention relates to a reflector unit wherein length L is calculated as the length of the supporting element between the vertical member and the first member.

According to yet another aspect, the present invention relates to a reflector unit wherein: the vertical member is provided with a slot; the supporting element is connected to the first member at its first end and is provided with a plurality of through holes along its length in close proximity to its second end; wherein the supporting element is engaged with the vertical member by matching the slot with one of the through holes in the supporting element.

According to still another aspect, the present invention relates to a reflector unit wherein length L of the supporting element is varied by engaging the supporting element with the vertical member through a different through hole.

According to a further aspect, the present invention relates to a reflector unit wherein the supporting element is divided into first and second sections, each section having a first end and a second end; wherein the first end of the first section is connected to the vertical member and the first end of the second section is connected to the first member; wherein each section is provided with a plurality of through holes along its length in close proximity to its second end; and wherein the first section is engaged with the second section by matching one of the through holes in the first section with one of the through holes in the second section.

According to a still further aspect, the present invention relates to a reflector unit wherein length L of the supporting element is varied by engaging the first section with the second section through a different through hole.

According to another aspect, the present invention relates to a reflector unit wherein the first member is hingedly coupled to the mounting element.

According to still another aspect, the present invention relates to a reflector unit wherein the first member is coupled to the mounting element by means of a nut-bolt assembly.

According to yet another aspect, the present invention relates to a reflector unit wherein the solar PV unit comprises a vertical limb positioned parallel to the vertical member for providing additional support to the mounting element.

According to a further aspect, the present invention relates to a reflector unit wherein the solar PV unit comprises a support limb provided between the mounting element and vertical member for providing additional support to the mounting element.

According to a furthermore aspect, the present invention relates to a reflector unit capable of being retrofitted to a pre-installed solar PV array, the solar PV array including a mounting element having first and second ends; a plurality of solar PV modules longitudinally spaced apart and fixed over the mounting element thereby forming the PV array; and first and second vertical members positioned on first and second ends of the mounting element, said mounting element being fixed over the vertical members in an inclined position, the reflector unit comprising: a first member having first and second ends; a reflector module mounted over the first member, said first member being coupled to the mounting element such that the reflector module is positioned behind the plurality of solar PV modules; a first supporting element provided between the first vertical member and the first member; and a second supporting element provided between the second vertical pillar and the first member; wherein the first and second supporting elements are configured for supporting the first member at an angular position with respect to a horizontal plane; wherein the first and second supporting elements are configured to vary the angular position of the first member with respect to the horizontal plane; and wherein the said angular position is varied by varying length L of the supporting elements.

According to a still further aspect, the present invention relates to a reflector unit wherein the solar PV array comprises a plurality of vertical limbs positioned between the first and second vertical members, said plurality of vertical limbs being configured to provide support to the mounting element.

According to a still further aspect, the present invention relates to a reflector unit wherein length L is calculated as the length of the supporting elements between the vertical members and the first member.

The present invention will be described herein below with reference to the accompanying drawings. In the following description well known functions or constructions are not described in detail since they would obscure the description with unnecessary detail.
Referring now to the drawings, there is shown an illustrative embodiment of the reflector unit that can be retrofitted to a pre-installed solar PV unit according to the present invention. It should be understood that the invention is susceptible to various modifications and alternative forms; specific embodiments thereof have been shown by way of example in the drawings and will be described in detail below.

The following paragraphs describe the present invention with reference to figures 1-3.

In general, the present invention relates to retro-fitment of a reflector unit to a pre-installed solar PV unit. The reflector unit including a reflector module is retro-fitted to a pre-installed solar PV unit including a solar PV module for generating electricity. The present invention provides a technique of retro-fitment where the reflector module is positioned behind the solar PV module.

Further, according to the present invention, the reflector unit can be coupled to any preinstalled solar PV unit without having to taking into account the design of the PV unit.

Furthermore, the present invention meets the requirement of seasonal tracking by changing the alignment of the reflector module.

Referring now to the drawings, there are shown illustrative embodiments of retro-fitment of a reflector unit to a pre-installed solar PV unit. It should be understood that the invention is susceptible to various modifications and alternative forms; specific embodiments thereof have been shown by way of example in the drawings and will be described in detail below.

The following paragraphs describe the present invention with reference to figures 1-3.

Figure 1a, shows a reflector unit coupled/connected to a solar PV unit according to an embodiment of the present invention.
As shown in figure 1a, the solar PV unit comprises of at least one solar PV module (10), a vertical member (11) fixed over a horizontal surface and a mounting element (12). The solar PV module (10) is mounted over the mounting element (12) which is fixed over the vertical member (11) in an inclined position. The mounting element (12) is fixed over the vertical member (11) by means of a nut-bolt assembly.
The solar PV unit further includes a support limb (13) provided between the vertical member (11) and the mounting element (12). Said support limb (13) connects the vertical member (11) with the mounting element (12) thereby providing additional support to the mounting element (12). The support limb (13) is connected to the vertical member (11) and mounting element (12) by means of nut-bolt assembly.

Further, as shown in an alternative embodiment of figure 1c, the solar PV unit further includes a vertical limb (14) positioned parallel to the vertical member (11). Said vertical limb (14) is also configured to provide additional support to the mounting element (12). The vertical limb (14) is connected to the mounting element (12) by means of a nut-bolt assembly.

Further, as shown in figure 1a, the reflector unit comprises of a reflector module (15), a first member (16) and a supporting element (17). The reflector module (15) is mounted over the first member (16). The first member (16) is coupled to the mounting plate (12) such that the reflector module (15) is positioned behind the solar PV module (10).

In an aspect of this embodiment, the first member (16) is coupled to the mounting element (12) by means of a hinge joint.

In another aspect of this embodiment, the first member (16) is coupled to the mounting element (12) by means of a nut-bolt assembly.

Furthermore, as shown in figure 1a, the supporting element (17) is provided between the vertical member (11) and the first member (16) for supporting the first member (16) at an angular position with respect to a horizontal plane. The said horizontal plane is parallel to the horizontal surface over which the vertical member (11) is installed. The supporting element (17) provides a link/connection between the vertical member (11) and the first member (16). The supporting element (17) also provides additional support to first member (16) supporting the reflector module (15).

From the arrangement shown in figure 1a, it can be noticed that the reflector module (15) is positioned behind the solar PV module (10) and reflects light on the PV module (10) located exactly behind it in the next/adjacent row. The said arrangement avoids shading effect which usually occurs in most of the reflector configurations.

Further, as shown in figure 1b, the reflector module (15) is positioned in such a way that there is approximately 2 meters distance between the bottom edge of the reflector module (15) and the bottom edge of the PV module (10) located exactly behind it, in the next/adjacent row so as to allow human/vehicular movement for maintenance.

Figure 1c, shows the retro-fitment of the reflector unit to the solar PV unit according to another embodiment of the present invention.

As shown in figure 1c, the design of the solar PV unit is changed as compared to the design in figure 1a, which implies that the design of reflector unit should also be changed accordingly (following the technology known in the art for this purpose). However, the present invention provides an improved way of connecting the reflector module (15) to the solar PV module (10) without depending on the design of the PV unit.

In other words, according to the present invention a reflector module (15) can be installed in any solar PV plant without having to taking into account the design of the structure supporting the PV module (10).

For instance, figure 1c, shows the design of the solar PV unit is modified, for example while installation of a different unit in the same solar PV plant or while installation of a totally different solar PV plant.

It can be noticed from figure 1c, the PV unit has been modified to eliminate the support limb (13) and include vertical limb (14). Further, it can be noticed from figure 1c that the design of the reflector unit is the same as shown in figure 1a. This clearly shows that, the reflector unit can be retro-fitted to any preinstalled solar PV unit without taking into account the design of the PV unit.
Further, it is known that as the sun moves up and down in the south sky as the seasons change, the output of solar PV plants change with the angle of the sun. Solar PV plants produce the most energy when the sunlight is hitting them directly. Therefore, it becomes necessary to change the mounting angle of the solar PV module or reflector module to follow the seasons in a particular area for producing energy at the maximum potential for each season.
According to the present invention, the mounting angle of the reflector module (15) is changed to meet the requirement of seasonal tracking as shown in figures 2a and 2b. The reflector is designed for application on Fixed PV units with tilt-angles in the range of 10-60 degrees.
As shown in figure 2a, the supporting element (17) is connected to the first member (16) at its first end (17a) by a nut-bolt assembly and is provided with a plurality of through holes (18) along its length in close proximity to its second end (17b). The vertical member (11) is provided with a slot (19). The supporting element (17) is engaged with the vertical member (11) by matching the slot (19) with one of the through holes (18) in the supporting element (17) and fixing the position by means of a nut bolt assembly. In this manner, the supporting element (17) supports the first member (16) at an angular position with respect to the horizontal plane.
According to an embodiment of the present invention, the angular position of the first member (16) with respect to the horizontal plane can be changed / varied by the supporting element (17). The said angular position can be varied by varying length L of the supporting element (17) between the vertical member (11) and the first member (16). Length L of the supporting element (17) is calculated as the length between the vertical member (11) and the first member (16). It is to be noted that this length shall appear to vary due to adjustment of supporting element (17) over the provided holes for angle adjustment whereas the actual length of the supporting element (17) shall remain unchanged.
In this embodiment of the present invention, length L of the supporting element is varied by engaging the supporting element (17) with the vertical member (11) through a different through hole (18). This is achieved by matching the hole (19) with a different through hole and fixing the new position by means of a nut bolt assembly.
The supporting element (17) is engaged with the vertical member (11) at different positions so as to increase or decrease the length L of the supporting element (17) thereby causing a change in the angle of inclination of the first member (16).
In an alternative embodiment, as shown in figure 2b, the supporting element (17) is divided into a first section (20) and a second section (21). The first section (20) is connected to the vertical member (11) and the second section (21) is positioned behind the first section (20) and is connected to the first member (16). Particularly, the first section (20) has a first end (20a) connected to the vertical member (11) and is provided with a plurality of through holes (22) along its length in close proximity to its second end (20b). The second section (21) has a first end (21a) connected to the first member (16) and is provided with a plurality of through holes (23) along its length in close proximity to its second end (21b). The first section (20) and second section (21) are connected to the vertical member (11) and the first member (16) respectively by means of a nut-bolt assembly.

The first section (20) and second section (21) are engaged with each other for supporting the first member (16) at an angular position with respect to the horizontal plane. The first section (20) and the second section (21) are engaged with each other by matching one of the through holes (22) in the first section (20) with one of the through holes (23) in the second section (21) and fixing the position by means of a nut bolt assembly. In this manner, the supporting element supports the first member (16) at an angular position with respect to the horizontal plane.

The said angular position can be varied by varying length L of the supporting element between the vertical member (11) and the first member (16).

In this embodiment of the present invention, length L of the supporting element is varied by engaging the first section (20) with the second section (21) through a different through hole. This is achieved by engaging one of the through holes (22) in the first section (20) with a different through hole (23) in the second section (21) and fixing the new position by means of a nut bolt assembly.

This can also be achieved by engaging one of the through holes (23) in the second section (21) with a different through hole (22) in the first section (21) and fixing the new position by means of a nut bolt assembly.
The above engagements at different positions enable the increase or decrease of the length L of the supporting element thereby causing a change in the angle of inclination of the first member (16).

Furthermore, in another embodiment of the present invention, the reflector unit can be retro-fitted to a solar PV array including a plurality of solar PV modules. The solar PV array includes a mounting element having first and second ends over which a plurality of solar PV modules can be mounted. In this embodiment, the solar PV modules are longitudinally spaced apart and fixed over the mounting element thereby forming the PV array.

The solar PV array includes first and second vertical members positioned on first and second ends of the mounting element and supports the mounting element in an inclined position.

As described earlier with reference to figures 1 and 2, the first member of the reflector unit is coupled to the mounting element. In this way, the reflector module mounted over the first member is positioned behind the plurality of solar PV modules.

Further, in this embodiment the reflector unit comprises of a first supporting element provided between the first vertical member and the first member and a second supporting element provided between the second vertical pillar and the first member. The first and second supporting elements are configured for supporting the first member at an angular position with respect to a horizontal plane.

Further, the first and second supporting elements are configured to vary the angular position of the first member with respect to the horizontal plane. The angular position is varied by varying length L of the supporting elements in the same manner as described above with reference to figure 2.

Furthermore, in this embodiment solar PV array comprises a plurality of vertical limbs positioned between the first and second vertical members, said plurality of vertical limbs being configured to provide support to the mounting element.
Figure 3 shows the energy generation report of a solar PV plant from a period of August 2014 to March 2015. It can be noticed from figure 3 that the energy generation has increased by 4.15% as a result of retro-fitment of the reflector unit to the solar PV unit.
It is to be understood that the technique of the present invention is not limited to the PV units mentioned above. Instead, according to the present invention, the reflector unit can be retrofitted to any preinstalled PV unit in any solar PV plant.

Further, it is to be noted that the reflector material used in the present invention is having a high reflectivity of more than 90%. The reflector module of the present invention is mounted over the first member by means of clamps or adhesives.

ADVANTAGES OF THE INVENTION
• Ease of maintenance- By allowing human/vehicular movement between two adjacent rows of PV units;
• Seasonal tracking- By changing the angle of inclination of the reflector according to the position of the sun;
• Low installation cost;
• Low cost reflector material is used;
• Reflector provides more than 90% reflectivity;
• As the reflector unit can be retrofitted to any PV unit, surface grading is not required; and
• Efficient- By providing an increase in the efficiency of solar PV plants.

The present invention is described with reference to the figures and specific embodiments; this description is not meant to be construed in a limiting sense. Various alternate embodiments of the invention will become apparent to persons skilled in the art upon reference to the description of the invention. It is therefore contemplated that such alternative embodiments form part of the present invention.

,CLAIMS:
1. A reflector unit capable of being retrofitted to a pre-installed solar PV unit, the solar PV unit including a mounting element; a solar PV module fixed over the mounting element; and a vertical member, said mounting element being fixed over the vertical member in an inclined position, the reflector unit comprising:
a first member;
a reflector module mounted over the first member, said first member being coupled to the mounting element such that the reflector module is positioned behind the solar PV module; and
a supporting element provided between the vertical member and the first member for supporting the first member at an angular position with respect to a horizontal plane;
wherein the supporting element is configured to vary the angular position of the first member with respect to the horizontal plane; and
wherein the said angular position is varied by varying length L of the supporting element.

2. The reflector unit as claimed in claim 1, wherein length L is calculated as the length of the supporting element between the vertical member and the first member.

3. The reflector unit as claimed in claim 1, wherein:
the vertical member is provided with a slot;
the supporting element is connected to the first member at its first end and is provided with a plurality of through holes along its length in close proximity to its second end;
wherein the supporting element is engaged with the vertical member by matching the slot with one of the through holes in the supporting element.

4. The reflector unit as claimed in claims 1-3, wherein length L of the supporting element is varied by engaging the supporting element with the vertical member through a different through hole.

5. The reflector unit as claimed in claim 1, wherein the supporting element is divided into first and second sections, each section having a first end and a second end;
wherein the first end of the first section is connected to the vertical member and the first end of the second section is connected to the first member;
wherein each section is provided with a plurality of through holes along its length in close proximity to its second end; and
wherein the first section is engaged with the second section by matching one of the through holes in the first section with one of the through holes in the second section.

6. The reflector unit as claimed in claims 1, 2 and 5, wherein length L of the supporting element is varied by engaging the first section with the second section through a different through hole.

7. The reflector unit as claimed in claim 1, wherein the first member is hingedly coupled to the mounting element.

8. The reflector unit as claimed in claim 1, wherein the first member is coupled to the mounting element by means of a nut-bolt assembly.

9. The reflector unit as claimed in claim 1, wherein the solar PV unit comprises a vertical limb positioned parallel to the vertical member for providing additional support to the mounting element.

10. The reflector unit as claimed in claim 1, wherein the solar PV unit comprises a support limb provided between the mounting element and vertical member for providing additional support to the mounting element.

11. A reflector unit capable of being retrofitted to a pre-installed solar PV array, the solar PV array including a mounting element having first and second ends; a plurality of solar PV modules longitudinally spaced apart and fixed over the mounting element thereby forming the PV array; and first and second vertical members positioned on first and second ends of the mounting element, said mounting element being fixed over the vertical members in an inclined position, the reflector unit comprising:
a first member having first and second ends;
a reflector module mounted over the first member, said first member being coupled to the mounting element such that the reflector module is positioned behind the plurality of solar PV modules;
a first supporting element provided between the first vertical member and the first member; and
a second supporting element provided between the second vertical pillar and the first member;
wherein the first and second supporting elements are configured for supporting the first member at an angular position with respect to a horizontal plane;
wherein the first and second supporting elements are configured to vary the angular position of the first member with respect to the horizontal plane; and
wherein the said angular position is varied by varying length L of the supporting elements.

12. The reflector unit as claimed in claim 11, wherein the solar PV array comprises a plurality of vertical limbs positioned between the first and second vertical members, said plurality of vertical limbs being configured to provide support to the mounting element.

13. The reflector unit as claimed in claim 11, wherein length L is calculated as the length of the supporting elements between the vertical members and the first member.