Photovoltaic energy production system and method for controlling such a system

Abstract

Photovoltaic energy production system and method for controlling such a system. Photovoltaic energy production system, comprising a plurality of panels (P1 to P2), each panel (P1 to P2) comprising a photovoltaic module (6), and being mounted for rotation on a supporting structure (2 to 4) about an axis of rotation (A), a winding device (10) carried by a first attachment zone (Z1) of a first panel (P1), a fabric (14) configured to be attached by one of its ends (E1) to the winding device (10) and by a second of its ends (E2) to a second attachment zone (Z2) of a second panel (P2) so as to cover at least part of an area (ZS) of the ground located vertically below the fabric (14), the system being configured so that the fabric (14) winds up in the winding device (10) according to a relative position of the first and second fixation zones (Z1, Z2).Figure for the abridged version: Fig.1.

Description

Title of the invention: Photovoltaic energy production system and method for controlling such a system Technical field

[0001] The present invention relates to the production of photovoltaic energy, in particular the production of photovoltaic energy from photovoltaic panels, and more particularly to photovoltaic panels intended to be placed above agricultural crops. STATE OF THE ART

[0002] Currently, photovoltaic panels are used to convert solar energy in electrical energy. In applications such as agrivoltaics (or agriphotovoltaics or agrovoltaics), the arrangement of photovoltaic panels must be adapted to the needs of the types of plants. Agrivoltaics refers to the production of electricity using photovoltaic modules placed above agricultural crops.

[0003] Agriphotovoltaic installations are currently booming, in a context where the effects of global warming are increasingly felt and causing increasing damage to agricultural crops. Their development is carried out with several objectives: - limiting the artificialization of soils; - protect ground crops from the effects of global warming (increased evapotranspiration due to high temperatures, drying out, late frosts, etc.) and thus preserve current yields; - generate additional income through the sale of electricity; - provide new features (anti-hail or anti-insect nets, anti-freeze cover, recovery and controlled sprinkling of rainwater, etc.).

[0004] There are agrivoltaic systems where the photovoltaic panels are placed vertically, and are installed in a configuration of parallel rows. While such a system allows agricultural machinery to pass between the rows of panels, it does not protect crops, particularly from hail.

[0005] Other systems include photovoltaic panels placed high up on a gantry, so as to allow passage for agricultural machinery. The panels can be fixed or mobile, for example operated by a sun tracking system called a "tracker" in English, which means pursuit, in order to follow the movement of the sun. Some of these systems can be equipped with anti-hail nets attached to the gantry posts, below the panels. But this requires removing the nets manually, or by motorized means, when agricultural machinery must pass under the panels. In addition, the nets can be made traditionally using meshed ropes or made from plastic braiding. Anti-hail nets, which have a protective agricultural function, cover the entire surface below the photovoltaic panels. A disadvantage is that the nets generate a certain constant shading on the vegetation, depending on the mesh size of the net. And the more you want to protect crops against hail, the finer the mesh size must be and therefore the more significant the shading.

[0006] There are also photovoltaic aviaries, equipped with nets extended between the edges of two photovoltaic panels located above the ground. But these nets can be very thin to best protect the plantations from hail, and offer significant shade. It is also necessary to remove them manually when one wishes to increase the light on the plantations, for example to improve the growth of agricultural crops.

[0007] An object of the invention is to overcome these drawbacks, and more particularly to provide means for improving the production of photovoltaic energy while protecting agricultural crops.

[0008] Another object of the invention is to provide simple and robust means.

[0009] Other objects, features and advantages of the present invention will become apparent from a consideration of the following description and accompanying drawings. SUMMARY

[0010] According to one aspect of the invention, a photovoltaic energy production system is proposed, comprising at least two panels, each panel comprising at least one photovoltaic module, each panel being supported at a distance from the ground by at least one supporting structure and being mounted to move in rotation on the supporting structure around an axis of rotation.

[0011] The system comprises a winding device carried by a first fixing zone of a first panel, a canvas configured to be hooked by a first of its ends to the winding device and by a second of its ends to a second fixing zone of a second panel so as to cover at least a portion of a zone of the ground situated vertically below the canvas, the system being configured so that the canvas is wound in the winding device as a function of a relative position of the first and second fixing zones.

[0012] Thus, a system is provided equipped with movable panels capable of following the movement of the sun to improve the production of photovoltaic energy while at least partially protecting the crops located below the canvas. Such a system is particularly simple to use. In addition, the canvas adapts particularly well to the movements of the panels. Such a system prevents the canvas from tearing when the panels are set in motion.

[0013] According to another aspect, a method is proposed for controlling a photovoltaic energy production system as defined above, comprising winding the fabric in the winding device during a change in the relative position of the first and second fixing zones. BRIEF DESCRIPTION OF THE FIGURES

[0014] Other advantages and characteristics will emerge more clearly from the following description of embodiments and implementations of the invention given as non-limiting examples and represented in the appended drawings, in which:

[0015] [Fig.l] [Fig.l] schematically illustrates a perspective view of an embodiment of a photovoltaic energy production system;

[0016] [Fig.2] [Fig.2] schematically illustrates a top view of another mode of construction of a photovoltaic energy production system;

[0017] [Fig.3] [Fig.3] schematically illustrates a sectional view of a mode of rea development of a photovoltaic energy production system in which the fabric is rolled up in the winding device;

[0018] [Fig.4] [Fig.4] schematically illustrates a sectional view of the system illustrated in [Fig.2], in which the canvas is unwound in the winding device;

[0019] [Fig.5] [Fig.5] schematically illustrates a sectional view of another mode of rea development of a photovoltaic energy production system;

[0020] [Fig.6] [Fig.6] schematically illustrates a perspective view of another mode of the creation of a photovoltaic energy production system;

[0021] [Fig.7] [Fig.7] schematically illustrates a top view of another mode of construction of a photovoltaic energy production system;

[0022] [Fig.8] [Fig.8] schematically illustrates another embodiment of a photovoltaic energy production system;

[0023] [Fig.9] [Fig.9] schematically illustrates a sectional view of the system illustrated in [Fig.8] ;

[0024] [Fig. 10] [Fig. 10] schematically illustrates a top view of another embodiment of a photovoltaic energy production system in which the canvas is detached from the second fixing zone;

[0025] [Fig. 11] [Fig. 11], schematically illustrates a top view of the system illustrated in [Fig. 10], in which the canvas is attached to the second fixing zone;

[0026] [Fig. 12] [Fig. 12] schematically illustrates a sectional view of the system illustrated in [Fig. 10];

[0027] [Fig. 13] [Fig. 13] schematically illustrates a sectional view of the system illustrated in [Fig. 11];

[0028] [Fig. 14] [Fig. 14] schematically illustrates a sectional view of another embodiment of a photovoltaic energy production system in which the fabric is wound in the winding device;

[0029] [Fig. 15] [Fig. 15], schematically illustrates a sectional view of the system illustrated in [Fig. 14], in which the canvas is unwound in the winding device;

[0030] [Fig. 16]

[0031] [Fig. 17] Figures 16 and 17, schematically illustrate perspective views of other embodiments of a photoelectric power generation system. DETAILED DESCRIPTION

[0032] Before beginning a detailed review of embodiments and implementations of the invention, optional features are set out below which may possibly be used in combination or alternatively.

[0033] According to one example, the system is configured so that, alternately, the fabric winds into the winding device when the first and second fixing zones move towards each other, and so that the fabric unwinds into the winding device when the first and second fixing zones move away from each other.

[0034] According to one example, each panel comprises a frame supporting said at least one photovoltaic module of the panel, and the first fixing zone corresponds to an edge of the frame of the first panel.

[0035] According to one example, each panel comprises a frame supporting said at least one photovoltaic module of the panel, and the second fixing zone corresponds to an edge of the frame of the second panel. Thus, the winding device can wind the canvas to stretch it according to the relative position of the edges of the first and second panels.

[0036] According to one example, the fabric extends over a length at least equal to 80%, preferably 100%, of a distance separating the first and second fixing zones.

[0037] According to one example, the system comprises an actuator configured to rotate the panels according to parameters relating to the path of the sun, and the winding device is configured to apply a force tending to wind the canvas in the winding device, said force being calibrated to allow free relative rotation of the panels.

[0038] According to one example, the winding device comprises a return element configured to apply a force tending to wind the fabric in the winding device.

[0039] According to one example, the canvas is flexible so as to deform under the action of its own weight.

[0040] According to one example, the canvas is openwork at least in part so as to allow rainwater to pass through.

[0041] According to one example, the canvas is configured to be removably attached to the second attachment zone.

[0042] According to one example, the canvas comprises at least one of hooks and rings complementary to the hooks, and the second attachment zone comprises the other of hooks and rings complementary to the hooks.

[0043] According to one example, the canvas comprises at least one first magnet and the second attachment zone comprises at least one second magnet configured to cooperate with said at least one first magnet so as to attach the canvas to the second attachment zone of the second panel in a removable manner.

[0044] According to one example, at least one of said at least one first and second magnet is electromagnetic such that electrical activation of the magnet suppresses cooperation of the first magnet and the second magnet.

[0045] According to one example, the actuating device comprises a winder mounted on the first movable fixing zone in rotation around an axis, called a winding axis, parallel to the axis of rotation of the first panel.

[0046] According to one example, the winding device comprises a motor configured to wind and unwind the fabric depending on a relative position of the first and second fixing zones.

[0047] In Figures 1 to 17, a system 1 for producing photoelectric energy is shown. The system 1 comprises at least one supporting structure 2 to 4, at least two panels PI to P3, and at least one canvas 14. A supporting structure 2 to 4 is configured to support one or more panels PI to P3 at a distance from the ground. A supporting structure 2 to 4 generally comprises two feet intended to be placed on the ground and a beam, or a supporting frame, connecting the two feet. The feet may be fixed to the ground, or alternatively each comprise wheels for moving the supporting structure 2 to 4 relative to the ground. Each panel PI to P3 is mounted on at least one supporting structure 2 to 4, for example on the beam or the supporting frame of the supporting structure. Preferably, each panel PI to P3 is mounted on a respective supporting structure 2 to 4. Furthermore, each panel PI to P3 comprises at least one photovoltaic module 6.A photovoltaic module 6 is configured to transform solar energy into electrical energy.

[0048] In particular, each panel PI to P3 is mounted so as to be able to rotate on the supporting structure 2 to 4 about an axis of rotation A. Preferably, the axis of rotation A is parallel to the ground. Preferably, each panel PI to P3 is mounted, on at least one supporting structure and preferably on each supporting structure 2 to 4, so as to be able to rotate about an axis of rotation A. For example, each axis of rotation A of a panel PI to P3 is parallel to the ground. Thus, the panels can be oriented so that the photovoltaic modules 6 are positioned facing the sun during the day in order to increase the production of photovoltaic energy compared to panels which would remain immobile relative to the ground. Preferably, the axes of rotation A of the panels PI to P3 are parallel to each other but not coaxial.

[0049] For example, each panel PI to P3 comprises a frame 5 supporting the photovoltaic module(s) 6 of the panel PI to P3. Generally, each frame 5 has a main edge BP extending longitudinally in a main direction DP and a secondary edge BS extending longitudinally in a secondary direction DS parallel to the main direction DP. For example, the main direction DP is parallel to the ground. According to another example, the main DP and secondary DS directions are parallel to the axis of rotation A of the panel PI to P3.

[0050] Generally, the system 1 comprises at least one winding device 10 to 13. In particular, at least one panel PI to P3 comprises at least one winding device 10 to 13. More particularly, a winding device 10, called the main winding device, is carried by a first fixing zone ZI of a first panel PI. The canvas 14 is configured to be attached by a first of its ends E1 to the main winding device 10 and by a second of its ends E2 to a second fixing zone Z2 of a second panel P2. Advantageously, the canvas 14 is configured to cover at least a portion of a zone ZS of the ground located vertically below the canvas 14.

[0051] Thus, the canvas 14 can protect the crops located in said zone ZS of the ground.

[0052] The system 1 is further configured so that the fabric 14 is rolled up in the device main winding 10 as a function of a relative position of the first and second fixing zones Z1, Z2.

[0053] Thus, when the first and second panels PI, P2 are moved in rotation about their respective axis of rotation A, the canvas 14 can be kept attached to the fixing zones Z1, Z2 to continue to protect the zone ZS from the ground. In other words, the canvas 14 can be wound or unwound in the main winding device 10 depending on the rotation of the first and second panels PI, P2 about their axis of rotation A during the day. The canvas 14 makes it possible to provide thermal cover and protection against rain and hail to the crops arranged in the zone ZS, that is to say the zone of the ground situated vertically below the canvas 14.

[0054] The system is configured so that the fabric 14 winds into the main winding device 10 when the first and second fixing zones Z1, Z2 move towards each other. Alternatively, the system 1 is configured so that the fabric 14 unwinds into the main winding device 10 when the first and second fixing zones Z1, Z2 move away from each other. For example, the first fixing zone Z1 corresponds to the main edge BP of the frame 5 of the first panel PI. For example, the second fixing zone Z2 corresponds to the secondary edge BS of the frame 5 of the second panel P2. Thus, the main winding device 10 can wind the canvas 14 to tension it according to the relative position of the edges BP, BS of the first and second panels PI, P2.

[0055] In particular, the first and second panels PI, P2 are movable between a first position in which the first and second panels PI, P2 are oriented parallel to the ground, as illustrated in Figures 3, 5, 14, 16 to 17, and a second position in which the first and second panels PI, P2 are moved relative to the first position, as illustrated in Figures 1, 4, 6, and 15. In other words, in the first position, the frames 5 of the first and second panels PI, P2 each extend in a horizontal plane parallel to the ground. In the second position, the panels PI, P2 are inclined relative to the ground, that is to say that their frame 5 extends in a plane inclined relative to a horizontal plane.

[0056] In [Fig. 7] an example is shown, in which the winding device 10 comprises a winder 40 mounted on the first fixing zone Zl movable in rotation about an axis B, called the winding axis, parallel to the axis of rotation A of the first panel PI. The winder 40 has a cylindrical shape and extends longitudinally along the winding axis B. For example, the winder 40 is mounted on the frame 5 of the first panel PI, for example on the main edge BP of the first panel PI.

[0057] The winding device 10 may further comprise a motor 60 configured to wind and unwind the canvas 14 as a function of a relative position of the first and second fixing zones Z1, Z2. In this case, the canvas 14 is able to wind itself around the winding axis B. In [Fig. 14], an example is shown in which the motor 60 makes it possible to vary the tension of the canvas 14. It is thus possible to prevent the canvas from hanging too low, depending on the nature of the plants located in the zone ZS below, for example:

[0058] Advantageously, to facilitate the winding and unwinding of the canvas 14, the canvas 14 is flexible so as to deform under the action of its own weight. The canvas 14 may be perforated at least in part so as to allow a liquid, in particular rainwater, to pass through. Thus, the canvas 14 comprises openings shaped to be crossed by water, in particular from its face facing the sky to its face facing the ground. The openings of the canvas 14 may be shaped so that certain drops pass through the openings without encountering the canvas 14. Alternatively, the openings of the canvas 14 may be shaped so that all the drops passing through the openings impact the canvas before passing through it through the openings. This may contribute to diffuse rainwater in the form of microdroplets. Furthermore, an openwork canvas 14 avoids creating a pocket of water which would weigh down the canvas 14. An openwork canvas 14 also prevents rainwater from accumulating at the ends E1, E2 of the canvas 14, which could block the winding and unwinding of the canvas 14, or allow water to pass onto the modules 6, and reduce the production of photovoltaic energy. Advantageously, the canvas 14 may include a mesh to allow air to pass through and prevent hailstones from passing through.

[0059] Furthermore, when the canvas 14 is attached to the first and second fixing zones Z1, Z2, the canvas 14 extends over a length Lt at least equal to 80%, preferably 100%, of a distance DI separating the first and second fixing zones Z1, Z2. The length Lt and the distance DI can be measured along a direction C perpendicular to the main DP and secondary DS directions and contained in a plane containing the main DP and secondary DS directions.

[0060] The canvas 14 can occupy different deployed configurations. It is said that the canvas 14 occupies a deployed configuration

[0061] For example, the main winding device 10 is configured to tension the fabric 14 so that the fabric 14 forms a flat sheet, as illustrated in [Fig. 15], or a bowl, as illustrated in [Fig. 14]. The fabric 14 can be kept tensioned between the two fixing zones Z1, Z2. Furthermore, a surface St of the fabric 14 covering the zone ZS of the ground varies when the relative position of the first and second fixing zones Z1, Z2 varies. The surface St of the fabric 14 extends from the main winding device 10 to the second fixing zone Z2.

[0062] Advantageously, the system 1 may comprise an actuator 80 configured to rotate the panels PI to P3 around their respective axes of rotation A. The actuator 80 may be configured to drive the panels PI to P3 according to parameters relating to the path of the sun. The parameters relating to the path of the sun comprise at least one of: a parameter relating to the date and time, a parameter relating to the weather, a parameter relating to the position of the sun. The main winding device 10 is configured to apply a force tending to wind the canvas 14 in the main winding device 10. The force is calibrated to allow free relative rotation of the panels PI, P2. When the system 1 comprises a motor 60 for winding and unwinding the canvas 14, the motor 60 and the actuator 80 may be controlled by an electronic control unit, not shown for the sake of simplification.The electronic control unit may comprise a microprocessor or a programmable logic controller. The electronic control unit may control the motor 60 according to the positions of the panels PI, P2. In other words, the control of the motor 60 may be a slave to the control of the actuator 80 so as not to hinder the movements of the panels PI, P2.

[0063] For example, the main winding device 10 may comprise a return element configured to apply a force tending to wind the fabric 14 into the main winding device 10.

[0064] For example, the canvas 14 is configured to be removably attached to the second fixing zone Z2. In this case, the canvas 14 can be unhooked from the second fixing zone Z2, for example when it is desired to allow a maximum amount of sunlight to pass through to the zone ZS of the ground. The canvas 14 can be unhooked from the second fixing zone Z2 and the canvas 14 can be wound into the main winding device 10, as illustrated in [Fig. 5].

[0065] As illustrated in [Fig.8], the canvas 14 may comprise at least one of hooks 21 and rings 20 complementary to the hooks 21, and the second fixing zone Z2 comprises the other of hooks 21 and rings 20 complementary to the hooks 21.

[0066] Figures 10 to 13 show another embodiment in which the canvas 14 comprises at least one first magnet 30 and the second fixing zone Z2 comprises at least one second magnet 31 configured to cooperate with said at least one first magnet 30. Thus, the canvas 14 can be attached to the second fixing zone Z2 of the second panel P2 in a removable manner. Advantageously, one of said at least one first and second magnet 30, 31 is electromagnetic. Preferably the magnets 31 of the second fixing zone Z2 are electromagnetic. The electromagnetic magnets 31 can be powered by the modules 6 of the second panel P2. The electrical power supply makes it possible to unlock the magnets and release the canvas 14 from the second fixing zone Z2 of the second panel P2.Thus, the canvas 14 can be wound in the main winding device 10 of the first panel PL. As winding the canvas 14 is an action that is done to increase the penetration of the sun's rays to the plants, it is an action that is done during the day. The power supply can therefore be made with the current generated by the photovoltaic modules 6, via an electrical circuit, not shown for the sake of simplification, taking a portion of the current generated by the modules 6. Preferably, when the current flows in the second magnets 31, the second magnets 31 no longer cooperate with the first magnets 30, and the canvas 14 can be unhooked. Conversely, when the current does not flow in the second magnets 31, the second magnets 31 cooperate with the first magnets 30 and the canvas 14 is kept attached to the second zone Z2. Several magnets 31 can be distributed regularly along the secondary edge BS of the second panel P2.For example, the magnets 31 can be mounted on a bar 16 attached to the frame 5 of the modules 6. The magnets 31 can be electrically coupled to the same electrical circuit to be actuated simultaneously. In Figures 5, 6, 10 and 12, the canvas 14 is shown detached from the . second fixing zone Z2. In figures 1 to 4, 8, 9, 11 and 13 to 15 the canvas 14 is shown attached to the second fixing zone Z2.

[0067] In [Fig. 16], a variant is shown in which the first panel PI comprises an additional winding device 11 mounted on the secondary edge BS of the first panel PI. The additional winding device 11 is configured to unwind and wind an additional canvas 15, when the first and second panels PI, P2 occupy the first position. Each additional canvas 15 has a first end E1 mounted on the additional winding device 11 and the other end E2 can be secured to the ground, for example using hooks fixed to a fixing element fixed to the ground.The first panel PI may further comprise other additional winding devices 12, 13 mounted respectively on lateral edges of the frame 5 of the first panel PL. Each additional winding device 11 to 13 is configured to unwind and wind an additional canvas 15, when the first and second panels PI, P2 occupy the first position.

[0068] Furthermore, a method for controlling the photovoltaic energy production system 1 which has just been described comprises the following main step: winding the fabric 14 in the winding device 10 during a change in the relative position of the first and second fixing zones Z1, Z2.

Claims

Claims

1. Photovoltaic energy production system, comprising at least two panels (PI to P2), each panel (PI to P2) comprising at least one photovoltaic module (6), each panel (PI to P2) being supported at a distance from the ground by at least one supporting structure (2 to 4) and being mounted so as to be able to rotate on the supporting structure (2 to 4) about an axis of rotation (A), characterized in that the system comprises a winding device (10) carried by a first fixing zone (Zl) of a first panel (PI), a canvas (14) configured to be attached by a first of its ends (El) to the winding device (10) and by a second of its ends (E2) to a second fixing zone (Z2) of a second panel (P2) so as to cover at least part of an area (ZS) of the ground situated vertically below the canvas (14),the system being configured so that the canvas (14) is wound in the winding device (10) according to a relative position of the first and second fixing zones (Zl, Z2).,

2. System according to the preceding claim, configured so that, alternately, the canvas (14) winds up in the winding device (10) when the first and second fixing zones (Zl, Z2) move towards each other, and so that the canvas (14) unwinds in the winding device (10) when the first and second fixing zones (Zl, Z2) move away from each other.

3. System according to any one of the preceding claims, in which each panel (PI, P2) comprises a frame (5) supporting said at least one photovoltaic module (6) of the panel (PI, P2), and the first fixing zone (Zl) corresponds to an edge (BP) of the frame (5) of the first panel (PI).

4. System according to any one of the preceding claims, in which each panel (PI, P2) comprises a frame (5) supporting said at least one photovoltaic module (6) of the panel (PI, P2), and the second fixing zone (Z2) corresponds to an edge (BS) of the frame (5) of the second panel (P2).

5. System according to any one of the preceding claims, in which the fabric (14) extends over a length (Lt) at least equal to 80%, preferably 100%, of a distance (Dl) separating the first and second fixing zones (Zl, Z2).

6. System according to any one of the preceding claims, comprising an actuator (80) configured to rotate the panels (PI, P2) according to parameters relating to the path of the sun, and the winding device (10) is configured to apply a force tending to wind the canvas (14) in the winding device (10), said force being calibrated to allow free relative rotation of the panels (PI, P2).

7. A system according to any preceding claim, wherein the winding device (10) comprises a return element configured to apply a force tending to wind the fabric (14) into the winding device (10).

8. System according to any one of the preceding claims, in which the fabric (14) is flexible so as to deform under the action of its own weight.

9. System according to any one of the preceding claims, in which the canvas (14) is openwork at least in part so as to allow rainwater to pass through.

10. System according to any one of the preceding claims, wherein the canvas (14) is configured to be removably attached to the second fixing zone (Z2).

11. System according to the preceding claim, in which the canvas (14) comprises at least one of hooks (21) and rings (20) complementary to the hooks (21), and the second fixing zone (Z2) comprises the other of hooks (21) and rings (20) complementary to the hooks (21).

12. System according to any one of claims 10 to 11, wherein the canvas (14) comprises at least one first magnet (30) and the second fixing zone (Z2) comprises at least one second magnet (31) configured to cooperate with said at least one first magnet (30) so as to hook the canvas (14) to the second fixing zone (Z2) of the second panel (P2) in a removable manner, preferably at least one of said at least one first and second magnet (30, 31) is electromagnetic so that an electrical activation of the magnet (30, 31) suppresses the cooperation of the first magnet (30) and the second magnet (31).

13. System according to any one of the preceding claims, in which the actuating device (10) comprises a winder (40) mounted on the first fixing zone (Zl) movable in rotation around of an axis (B), called winding, parallel to the axis of rotation (A) of the first panel (PI).

14. System according to any one of the preceding claims, wherein the winding device (10) comprises a motor (60) configured to wind and unwind the canvas (14) depending on a relative position of the first and second fixing zones (Zl, Z2).

15. Method for controlling a photovoltaic energy production system according to any one of claims 1 to 14, comprising winding the fabric (14) in the winding device (10) during a change in the relative position of the first and second fixing zones (Zl, Z2).

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