WO2010146208A2

WO2010146208A2 - Solar tracker

Info

Publication number: WO2010146208A2
Application number: PCT/ES2010/070383
Authority: WO
Inventors: Gerardo Tenreiro Vazquez
Original assignee: Electrotecnica Industrial Y Naval, S.L.
Priority date: 2009-06-19
Filing date: 2010-06-08
Publication date: 2010-12-23
Also published as: ES2363393A1; WO2010146208A3; ES2363393B1

Abstract

The invention relates to a solar tracker that distributes internal loads and external loads over various points of the structure thereof, rendering the whole unit, formed by the photovoltaic solar panels and the supporting elements to which said panels are fixed, very safe, such that it can continue its normal operation, that is tracking the sun's trajectory, even if one of the support points to which the loads are distributed develops a fault. Said solar tracker can also be inclined at between 0° and 55° to the horizontal, in such a way that, in the face of strong winds, it can be positioned at 0° where it has the minimum resistance to the wind.

Description

SOLAR TRACKER

DESCRIPTION

OBJECT OF THE INVENTION

The present invention aims at a solar tracker that distributes its own loads and external loads on several points of its structure, providing high security to the whole set formed by photovoltaic solar panels, and the supports on which they are fixed .

Due to its special configuration, the solar tracker is able to follow its normal operation based on following the solar path, although some of the support points on which the charges are distributed have been damaged.

In addition, the solar tracker of the present invention can have an inclination from 0 ^or 55 ° with respect to the horizontal, so that in high winds it can be set to 0 ^or presenting in that position the minimum wind resistance.

BACKGROUND OF THE INVENTION

Solar trackers are known in the state of the art that ensure with greater or less precision an alignment of the normal vector to the surface of the photovoltaic panel placed on the follower with the imaginary line that joins the center of the panel and the sun.

The orientation required by the follower can be obtained through two angles that usually they correspond to a first angle of rotation along a vertical axis or azimuth and a second angle of rotation along a horizontal axis or in height.

Once the support structure is equipped with both angles, it is necessary to incorporate the drive and control means that determine at each moment the angular position of each degree of freedom.

The solar trackers based on a central bearing have a single support of the mobile structure on the support point, which implies that in the event of its failure there is no possibility of correcting its position.

Since there is only one support, it has to be able to support the entire load, so that the safety coefficient is established according to the total load of the mobile structure.

Likewise, when one of these single support solar trackers breaks down and it is necessary to proceed to repair it, it is necessary to completely raise the upper part, so it is necessary to carry out a complete disassembly of the mobile structure.

Moreover, these followers are designed for an orientation from an inclined position of approximately 10 degrees to 45 degrees in height, which limits the absolute inclination to 35 degrees.

In situations where high winds occur, the solar trackers are positioned so that it presents the minimum sail to the wind, to minimize its resistance to it, so that in the case of the previous solar trackers, the minimum angle is 10 degrees in height at best, therefore always presenting a high resistance to wind, with the consequent risk of damage associated with that exposure, in addition to not being designed to perform a full 360 ° rotation in azimuth, because They have to return to the starting position at the end of each day.

Likewise, solar trackers based on a single central turning element have to slow down the rotation to maintain the position, which is necessary brakes, that is, additional elements to the follower to carry out that task, elements that require consumption Additional system power.

Due to this, great wear on the bearings is produced due to the effect of the wind, since it continuously presses on the same bearing position while the orientation is not changed.

All the above drawbacks are overcome by the invention that is now described.

DESCRIPTION OF THE INVENTION

The present invention relates to a solar tracker that distributes its own loads and external loads over several points of its structure, providing high security to the entire assembly formed by the photovoltaic solar panels and the supports on which they are fixed.

The solar tracker features a first functional group or panel holder that supports the solar tracker panels. - TO -

The follower has a second functional group or shaft that serves as the basis for the entire solar tracker assembly and is connected to the first functional group through eight actuators that carry out the orientation both east-west and vice versa, as in the north-south direction and vice versa, of the solar tracker panels.

These eight actuators are two-to-two symmetrical and allow the own loads and the external loads supported by four supports of the first functional group to be distributed over eight supports of the second functional group, providing high security to the entire assembly and allow the follower to follow the solar path although one of the support points has broken down. In this way, the follower is still in operation while this support is repaired.

Each group of two actuators has a symmetrical configuration with respect to a vertical plane, the ends of the actuators that are articulated in the first functional group being closer than the ends of the actuators that are articulated in the second functional group, so that they balance their respective thrusts and the efforts do not cause damage to the structure of the follower.

DESCRIPTION OF THE DRAWINGS

The present specification is complemented with a set of drawings, illustrative of the preferred and never limiting example of the invention.

Figure 1 shows an in perspective view bottom of the solar tracker of the present invention.

Figure 2 shows an elevation view of the solar tracker of Figure 1.

Figure 3 shows a perspective view of a flange on which the first functional group of the follower rests and where the mobile rods of the mechanical actuators are joined.

Figure 4 shows a perspective view of the joining means between the first and the third functional group.

PREFERRED EMBODIMENT OF THE INVENTION

In view of the foregoing, the present invention relates to a solar tracker that has a first group (1) or panel carrier supports photovoltaic panels (4) and has an octagonal geometry, as seen in Figure 1 , and where four of its sides (1.1), facing two to two, are smaller than the other four sides (1.2) oblique to the sides of the perimeter formed by the sides of the photovoltaic panels.

Likewise, the first functional group (1) has internal sections (1.3) that are used to stiffen it.

These parts (1.1, 1.2, 1.3) that constitute the first functional group are formed by tubes of circular section.

The follower presents a second group (2) functional or shaft that serves as the basis of the entire solar tracker assembly and is connected to the first functional group (1) through eight actuators (3), which in this preferred embodiment are hydraulic cylinders, which carry out the orientation both in the east-west direction and vice versa, as in the north-south direction and vice versa, of the solar tracker panels, making a complete 360 ° turn.

These eight actuators are two to two symmetrical and each group of two actuators has a symmetrical configuration with respect to a vertical plane, the ends of the actuators that are articulated in the first functional group being closer than the ends of the actuators that are articulated in the second functional group, so that their respective thrusts are balanced and the efforts do not cause damage to the structure of the follower.

The union of the first functional group to the second functional group is carried out through flanges (6) shown in Figure 3 that have a seat (6.1) to house the circular section tubes of the first functional group (1).

In addition, these flanges have a first bolt (6.2) that allows the rotation of the first functional group (1) due to the movement of the actuators (3) that are articulated therein through two second bolts (6.3).

The follower has a third functional group (5) comprising a set of tubes on which the panels (4) are fixed, where the tubes are joined to the first functional group (1) through elements (7) connection or flanges, shown in Figure 4, which in turn are fixed to the first functional group (1).

Due to the circular geometry of the profile of each of the tubes of the third functional group (5), the response to the loads is the same in all directions.

Due to the 8 hydraulic cylinders (3), the resting position of the follower, the one where the panels (4) are parallel to the horizontal, and therefore the wind resistance is minimal, causes the load to be supported by the rod fixed (3.1) of said cylinders (3), and more specifically in the area of union with the second functional group (2), an area that is continuously lubricated by the oil arranged inside the fixed rod (3.1).

The energy consumed in the movements of the solar tracker is 200W, which means a saving of 50% compared to the followers based on the central axis. At the same time, since it does not need a brake, the energy consumed to maintain its position is only that used by the control elements, of the order of 3W.

The 8 hydraulic cylinders (3) are actuated by a single hydraulic pump and several valves for its movement, which makes a recovery of flow rates in the movements of lowering the cylinders, which are then used to drive them (3).

The follower has a hydraulic overpressure valve that, in high winds, positions the follower horizontally so that it presents the minimum wind resistance without the need for the hydraulic pump to operate, since the hydraulic circuit releases the pressure to a tank automatically, which implies that even in the absence of tension, the follower can be placed in that position.

By means of the hydraulic cylinders (3) the load is determined at all times by reading the hydraulic pressure in them, knowing if there are additional requests on the panels (4) and being able to act accordingly, in addition to knowing the imbalance of pressures between the different cylinders (3) and determine if there are anomalous lateral loads, taking the appropriate measures for their compensation.

Once the follower has reached the last position of the day, he returns to the initial position through the center, remaining in this safety position as long as no solar radiation is generated.

Inside the second functional group (2) or shaft, control, control and generation elements (not shown) of the rest of the follower elements are arranged.

Variations in materials, shape, size and arrangement of the component elements, described in a non-limiting manner, do not alter the essentiality of this invention, being sufficient to proceed to its reproduction by an expert.

Claims

I ^a .- Solar tracker characterized in that it has a first functional group (1) or panel carrier that supports the solar tracker panels and a second functional group (2) or shaft that serves as the basis of the entire solar tracker assembly and is attached to the first functional group (1) through eight actuators (3) that carry out the orientation both in the east-west direction and vice versa, as in the north-south direction and vice versa, of the solar tracker panels (4) .

2 .- solar tracker according to claim 1 characterized in that the eight actuators (3) are symmetrical two to two with respect to a vertical plane and allow own loads and external loads supported by four supports of the first functional group are distributed on eight supports of the second functional group.

3 .- solar tracker according to claim 2 characterized in that in each group of two actuators (3), the ends (3.2) of the actuators (3) which are articulated on the first group (1) functional are closer together than the ends (3.1) of the actuators (3) that are articulated in the second functional group, so that their respective thrusts are balanced and the stresses do not cause damage to the follower structure.

4 .- solar tracker according to claim 1 wherein bonding the first functional group (1) the second functional group (2) is effected via flanges (6) having a seat (6.1) to accommodate tubes section circular that make up the first functional group (1), and a first bolt (6.2) that allows the rotation of the first functional group (1) due to the movement of the actuators (3) that are articulated in it through two second bolts (6.3).

5 .- solar tracker according to claim 1 characterized by a third functional group (5) comprising a set of tubes on which the panels (4) where the tubes join the first group (1) through fixing functional of connecting elements (7) or flanges that are fixed to the first functional group (1).

6 .- solar tracker according to any of the preceding claims in that the actuators (3) are hydraulic cylinders so that in the rest position of the follower, one where the panels (4) are parallel to the horizontal load is supported by the fixed rod (3.1) of said cylinders (3), and more specifically in the junction zone with the second functional group (2), an area that is continuously lubricated by the oil arranged inside the fixed rod (3.1) .

7 .- The solar tracker according to claim 6 wherein the cylinder (3) for determining the hydraulic load at all times reading hydraulic pressure therein (3).

8 .- The solar tracker according to claim characterized in that within the second functional group (2) or shaft elements command, control and generation of other elements of the follower are arranged, between which is a hydraulic pump which drives Hydraulic cylinders

9 .- solar tracker according to claim 8 ca- Racterized because it has several valves to perform the movement of the hydraulic cylinders, valves that make a recovery of flows in the movements of lowering the cylinders, which are then used to drive them (3).

10 .- The solar tracker according to claim 8 characterized by a hydraulic valve overpressure at high wind positions the follower in horizontal arrangement so that it has a low wind resistance without acting hydraulic pump as the hydraulic circuit It releases the pressure to a tank automatically, which implies that even in the absence of tension, the follower can be placed in that position.