Support structure of photovoltaic panel

Abstract

The subject matter of the solution is a support structure for a photovoltaic panel comprising a bracket, a support beam and two uprights. The support structure is characterised in that there are at least two brackets (1), the length of which does not exceed the side walls (2) of the photovoltaic panel (3), transversely fixed at substantially the center point on a support beam (10), which extends over the width of the support structure (12) and is supported by two uprights (13) embedded in the ground, wherein the supports (1) are thin-walled parts of open profile and comprise at least one support wall (4) and a retaining wall (5) substantially perpendicular to the support wall (4), and the photovoltaic panels (3) are located on the support walls (4) of the two supports (1) between their retaining walls (5), and the support walls (4) do not extend beyond the width (A) of the frame (7) of the photovoltaic panels (3).

Description

Technical Field

[0001] The subject of the present solution is a support structure for photovoltaic panels.The disclosed solution relates to a freestanding, ground-mounted support structure, in particular for bifacial photovoltaic panels. Background Art

[0002] Photovoltaic installations are currently viewed as a multi-year investment, with an estimated payback period of 6 to 10 years, with the lifetime of the PV panels being up to 30 years. PV panels still only exploit a small fraction of the sun's energy. Various solutions are being sought to improve the efficiency of the panels. A relatively new solution is the bifacial module, where both sides of the panel's cells absorb sunlight. The other side of the panel gets its energy from reflected and diffused light, so the mounting position becomes extremely important, as does the support structure, which results in a reduction in light incidence. Many studies have shown that under baseline conditions (unrestricted light entry to the panel), in a position similar to that of a PV panel mounted on a support structure, with a reflectivity of 90%, the back of the module yields 40% of the front.

[0003] Separate support structures designed for double-sided panels are known in the prior art.

[0004] Utility model CN213879701U discloses a solution for a support structure designed for double-sided panels. A square tube main beam is connected to the columns at multiple support points. A truss is connected to the main beam, and the truss is supported by a bracket, which is additionally fixed to the main beam. The photovoltaic modules are above and below the main beam, between the diagonal supports, and the frames of the photovoltaic modules are fixed to the diagonal supports.

[0005] The basic premise of the support structure of a bifacial solar panel is to ensure, in addition to ensuring optimal sunlight exposure on the upper part of the panel, that sunlight reaches the other side of the panel as much as possible and that none of the cells in the panel are shaded. The way solar cells work (their series electrical connection) is such that all solar cells in the area of ​​one panel are the weakest of them all. However, not only shading affects the efficiency of solar cells. The performance of solar cells can also change adversely with increasing temperature.

[0006] The developers of this solution observed that the lifetime of photovoltaic cells located near the supporting structure (such as supporting beams) is the lowest. At the minimum distance, the air circulation is impaired and at high temperatures, and the developers observed that the temperature of adjacent photovoltaic cells is higher than that of other cells, which is related to the thermal radiation of the supporting beams directed to these cells. Therefore, the supporting structure may lead to a shortened lifetime of the photovoltaic panel. Summary of the invention

[0007] Therefore, the purpose of the present solution is to provide a support structure for photovoltaic panels, which has advantages over the prior art and also solves the disadvantages of shading and different temperatures of individual cells due to the influence of the support structure on the cells.

[0008] According to the present solution, the support structure of the photovoltaic panel comprises a bracket, a support beam and two columns. The support structure is characterized in that it has at least two brackets, whose length does not exceed the side wall of the photovoltaic panel, which are transversely fixed to the support beam at a substantially central point, the support beam extending over the width of the support structure and supported by two columns embedded in the ground, wherein the bracket is a thin-walled component with an open profile and includes at least one support wall and a retaining wall substantially perpendicular to the support arm. The photovoltaic panel is located on the support walls of the two brackets, between their retaining walls, and the support walls do not extend beyond the width of the photovoltaic panel frame. The thin-walled bracket structure adjacent to the photovoltaic panel frame does not restrict the light along the contour of the photovoltaic panel. The illumination of the outermost cells is effectively increased by 40% compared to panels supported by thick profiles along the sides. This increases the output on the back of the photovoltaic panel by more than 50%, resulting in an increase in the output of the entire panel by more than 10%.

[0009] Preferably, the frame of the photovoltaic panel is detachably connected to the supporting wall of the bracket from below by means of connecting means. The most common connection made by bolts on the underside allows the use of brackets whose top edge does not extend beyond the top wall of the panel frame, so that the panel absorbs more light. The light entering the top wall of the photovoltaic panel is not restricted.

[0010] In another preferred solution, the frame of the photovoltaic panel is detachably connected to the retaining wall of the bracket from the side by a connecting device. This allows the lower side of the panel frame and the supporting wall of the bracket to be thinner, and thus has less shading effect on the panel.

[0011] Preferably, the bracket comprises a top wall and a closing wall, wherein the top wall is substantially parallel to the supporting wall and is at most the width of the supporting wall, and the closing wall extends from the bottom edge of the supporting wall to the bottom edge of the retaining wall, and the photovoltaic panel is inserted between the top wall and the supporting wall of the two brackets and rests against the closing wall. This design allows the panel to be supported without a frame, wherein the bracket forms a pocket into which the panel can be inserted without the need to bolt the photovoltaic panel.

[0012] Preferably, the bracket is connected to the top wall and the closing wall, wherein the top wall is substantially parallel to the supporting wall and extends beyond the retaining wall without exceeding the supporting wall. The closing wall extends from the lower edge of the top wall to the retaining wall. The photovoltaic panel is inserted between the top wall and the supporting wall of the two brackets and rests on the closing wall.

[0013] Preferably, the bracket is connected to the support beam by means of supports and connecting means. The supports can allow components of the structure to be moved away from the photovoltaic cells, which helps light to better enter the panels in the area of ​​the support beam and thereby ensures that the cells operate more evenly, thereby reducing current intensity differences and extending panel life.

[0014] Preferably, the support beam is fixed to the column by an adjustment mechanism. The adjustment mechanism comprises a movable part connected to the support beam and a position lock, the movable part being pivotally connected to the column with the axis of rotation parallel to the support beam. The adjustment mechanism allows adjusting the inclination of the panel according to the maximum height of the sun above the horizon, which varies all year round. This solution is designed for latitudes far from the tropics, where the efficiency of solar equipment is low and there is no return on investment in tracking systems. The premise of this solution is to manually change the inclination of the panel several times a year, according to the height of the sun above the horizon at a specific time of the year.

[0015] Preferably, all elements of the support structure are white and have a rough surface. White walls reflect light best, while rough walls reflect light diffusely. The accumulation of light beams reflected from the support structure causes uneven lighting, which reduces efficiency and panel life.

[0016] Preferably, trims are mounted at the bottom of the uprights, and the reflectors extend between the trims. Due to the use of reflective elements, more reflected light reaches the lower surface of the panel.

[0017] Preferably, the reflective element is a white tarpaulin or panel with a reflectivity greater than 40%. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The subject matter of the present solution is illustrated by way of examples without limiting its scope. The present solution is shown in the accompanying drawings:

[0019] Figure 1 – Axonometric view of variant 1 of the support structure

[0020] Figure 2 – Panel frame fixed to the support wall of the bracket

[0021] Figure 3 – Axonometric view of variant 2 of the supporting structure

[0022] Figure 4 – Axonometric view of variant 3 of the support structure

[0023] Figure 5 – Illumination on the underside of the panel

[0024] Figure 6 – Prior art: Illumination on the underside of the panel DETAILED DESCRIPTION

[0025] Figure 1A first embodiment of a support structure for three photovoltaic panels is shown, which includes four brackets 1, a support beam 10, and two columns 13. The bracket 1, which has a length of 60% of the side wall 2 of the photovoltaic panel 3, is laterally fixed to the support beam 10 at a substantially center point. The bracket 1 is a thin-walled component with an open profile and includes two support walls 4 and a substantially vertical retaining wall 5 connected by a connecting wall 19. The plane of the retaining wall 5 is substantially vertical, and the support walls 4 of all brackets 1 in the structure are in one plane. Two support walls 4 of adjacent brackets are located between the retaining walls 5. The distance between the retaining walls 5 of adjacent brackets 1 is 2 mm larger than the width of the photovoltaic panel 3. Alternatively, the width can be up to 20 mm larger than the width of the photovoltaic panel 3. As Figure 2 As shown, the connection is made by two supports 11 (angle brackets) which are bolted to opposite sides of the support beam 10 and whose upper surface is connected to the connecting wall 19 of the bracket 1 by using a connecting device 17 (standard bolt connection element). The support beam 10 extends over the width of the support structure 12 and is supported by two uprights 13 embedded in the ground (anchored to the ground). The height of the retaining wall does not exceed the height of the photovoltaic panel frame. The photovoltaic panels 3 are located on the support walls 4 of two adjacent brackets 1, between their retaining walls 5. The support wall 4 does not extend beyond the width A of the frame 7 of the photovoltaic panel 3.

[0026] In the first embodiment, the frame 7 of the photovoltaic panel 3 is detachably connected to the support 1 by means of a connection device 17 as a bolt connection element. Figure 2 In FIG. 1 , a cross section of a bracket 1 is shown, revealing the attachment of a support wall 4 to the bracket 1 from below.

[0027] The support beam 10 is fixed to the column 13 via an adjustment mechanism 14, which comprises a movable part 15 connected to the support beam 10 and a position lock. The movable part 15 is pivotally connected to the column 13, wherein the axis of rotation is parallel to the support beam 10. The position lock is realized by two bolt connections and adjustment holes in the movable part 15, wherein the adjustment mechanism allows the support beam 10 to rotate around the axis (axis of rotation) of the upper bolt connection, and the lower bolt connection acts as a position lock, whose position changes according to the hole selected in the movable part 15.

[0028] exist Figure 3 In another embodiment shown, the bracket 1 is connected to a top wall 8 and a closing wall 9 formed by a single bent sheet. The top wall 8 is substantially parallel to the supporting wall 4 and extends beyond the retaining wall 5, not exceeding the supporting wall 4. It is located on the connecting wall 19 and is bolted to the connecting wall 19. The closing wall 9 extends from the lower edge of the top wall 8 to the retaining wall 5, perpendicular to the retaining wall 5. This embodiment shows a structure suitable for three photovoltaic panels 3, two of which are sandwiched between the top wall 8 and the supporting wall 4 of the adjacent bracket 1, and the lower part of the frame 7 rests on the closing wall 9.

[0029] exist Figure 4 In another embodiment shown, the structure differs from the first embodiment in that there are six brackets 1, each bracket comprising a supporting wall 4 and a retaining wall 5, a top wall 8 and a closing wall 9. The top wall 8 is substantially parallel to the supporting wall 4 and is the width of the supporting wall 4, and the closing wall 9 extends from the bottom edge of the retaining wall 5 to the width of the supporting wall 4. The photovoltaic panel 3 is inserted between the top wall 8 and the supporting wall 4 of the two brackets 1 and rests on the closing wall 9. The bracket 1 is connected to the supporting beam 10 by means of a support 11 and a connecting device 17. At the lower part of the column 13, a trim 16 is installed, and a reflective element 18 extends between the trim 16, and the reflective element 18 is a white tarpaulin or board with a reflectivity greater than 40%.

[0030] Figure 5 and Figure 6 It is shown that for a bracket compatible with the proposed support structure ( Figure 5 ) and brackets known in the prior art, the illuminance on the underside of the photovoltaic panel at the same exposure, where the profile dimensions of the supporting panel frame greatly exceed it. In extreme cases, the power on the underside drops by up to 50% or more due to the brackets shading the end cells, which are connected in series in the installation, limiting the power of the other cells.

Claims

1. A supporting structure for a photovoltaic panel, comprising a bracket, a supporting beam and two columns, It is characterized in that There are at least two brackets (1) whose length does not exceed the side walls (2) of the photovoltaic panel (3), which are transversely fixed at a roughly central point on a support beam (10), which extends over the width of a support structure (12) and is supported by two columns (13) embedded in the ground, wherein the bracket (1) is a thin-walled component with an open profile and includes at least one support wall (4) and a retaining wall (5) substantially perpendicular to the support wall (4), and the photovoltaic panel (3) is located on the support walls (4) of the two brackets (1), between their retaining walls (5), and the support walls (4) do not extend beyond the width (A) of the frame (7) of the photovoltaic panel (3).

2. The support structure according to claim 1, wherein the frame (7) of the photovoltaic panel (3) is detachably connected to the support wall (4) of the bracket (1) from below by means of a connecting device (17).

3. The support structure according to claim 1, wherein the frame (7) of the photovoltaic panel (3) is detachably connected to the retaining wall (5) of the support (1) from the side by means of a connecting device (17).

4. A support structure according to claim 1, wherein the bracket (1) comprises a top wall (8) and a closed wall (9), wherein the top wall (8) is substantially parallel to the supporting wall (4) and is at most the width of the supporting wall (4), and the closed wall (9) extends from the bottom edge of the supporting wall (4) to the bottom edge of the retaining wall (5), and the photovoltaic panel (3) is inserted between the top wall (8) and the supporting wall (4) of the two brackets (1) and rests against the closed wall (9).

5. A support structure according to claim 1, wherein the bracket (1) is connected to a top wall (8) and a closed wall (9), wherein the top wall (8) is substantially parallel to the supporting wall (4) and extends beyond the retaining wall (5) but not beyond the supporting wall (4), and the closed wall (9) extends from the lower edge of the top wall (8) toward the retaining wall (5), and the photovoltaic panel (3) is inserted between the top wall (8) and the supporting wall (4) of the two brackets (1) and rests against the closed wall (9).

6. A support structure according to any one of claims 1 to 5, wherein the bracket (1) is connected to the support beam (10) by means of a support member (11) and a connecting device (17).

7. A support structure according to any one of claims 1 to 5, wherein the support beam (10) is fixed to the column (13) by an adjustment mechanism (14), the adjustment mechanism (14) comprising a movable part (15) connected to the support beam (10) and a position lock, the movable part (15) being pivotally connected to the column (13), wherein the rotation axis is parallel to the support beam (10).

8. The support structure according to at least one of the preceding claims, wherein all elements of the support structure (12) are white and have a rough surface.

9. Support structure according to at least one of the preceding claims, wherein trims (16) are mounted at the bottom of the uprights (13), the reflective elements (18) extending between the trims (16).

10. The support structure according to claim 9, wherein the reflective element (18) is a white tarpaulin or panel with a reflectivity greater than 40%.

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