WO2009054020A2

WO2009054020A2 - A support device for photovoltaic panels which are intended for electrical energy production plants

Info

Publication number: WO2009054020A2
Application number: PCT/IT2008/000659
Authority: WO
Inventors: Alessandro Chiorlin
Original assignee: Alessandro Chiorlin
Priority date: 2007-10-25
Filing date: 2008-10-22
Publication date: 2009-04-30
Also published as: ITPD20070357A1; WO2009054020A3

Abstract

A device for supporting photovoltaic panels (13) which are intended for electrical energy production plants comprises at least a first shaft (11) rotatably supported on a first support (9) about a first rotation axis (X), with respect to which the surfaces of the panels (13) collecting the light radiation are oriented, and at least one chassis (12) arranged to house one or more of the photovoltaic panels (13), as well as first motor means (16) operatively associated with the first support shaft for controlling the rotation of the same about the first axis, there being provided in the kinematic transmission, between the first motor means and the first control shaft, first braking means (18), which can be selectively activated, to lock the first shaft (11) in a first preselected angular position. The device also comprises at least a second stationary support (2) supporting the device, the first support (9) being rotatably supported on the second support about a second rotation axis (Z), and second motor means (8) operatively associated with the first support (9) for controlling the rotation of the same about the second axis (Z), in which, in the kinematic transmission between the second motor means and the first support, there are provided second braking means (20), which can be selectively activated, to lock the first support (9) in a preselected angular position, securing the first support (9) with the stationary structure supporting the second support (2).

Description

A SUPPORT DEVICE FOR PHOTOVOLTAIC PANELS WHICH ARE INTENDED FOR ELECTRICAL ENERGY PRODUCTION PLANTS

Technical field

The present invention relates to a support device for photovoltaic panels which are intended for electrical energy production plants, having the features set out in the preamble of main Claim 1. Technological background

In the technical field of plants for electrical energy production by the conversion of light radiation through the photovoltaic effect, elements collecting the radiation (photovoltaic cells) are used, as is well known, and are produced in the form of panels which are fitted to support structures capable of being controlled in an orientation movement about one or more axes. An example of a support having the abovementioned features is known from the Italian patent application PD2006A000165 in the name of the same Applicant. There is described a support structure with orientation about a single axis, comprising a support shaft rotatably supported about the aforementioned axis, and on which are bound photovoltaic panels forming the collecting surface for the light radiation. There is also described a kinematic transmission between a motor element and the shaft to transmit the rotation driving motion to the same about the orientation axis. In the kinematic transmission there are provided, between the motor and the support shaft for the panels, braking means, which can be selectively activated, to lock the shaft in a preselected angular position, securing the shaft with the stationary support structure of the support device. Since these support devices are normally exposed to stresses and/or vibrations arising mainly from external actions including those of a meteorological nature (for example due to the wind), which are moreover amplified due to the width of the collecting surfaces, the kinematic transmission is subjected to premature wear and to phenomena of localized damage. Even the anchorage and fixing systems of the structures provided in such devices are subjected to such phenomena, with the risk of possible collapses due to the fixing elements being unscrewed or loosened. Description of the invention The main aim of the invention is to provide a support device with two or more axes of orientation of the surface collecting the radiation, which device is designed to overcome the limits and drawbacks mentioned above with reference to the cited prior art. This aim is achieved by a device for supporting photovoltaic panels, which device is produced in accordance with the claims that follow. Brief description of the drawings

The features and advantages of the invention will become clear from the following detailed description of one of its preferred embodiments illustrated, by way of indication and in a non-limiting manner, with reference to the appended drawings in which :

- Figure 1 is a side elevation view of a device for supporting photovoltaic panels, which device is produced in accordance with the present invention, Figures 2 and 3 are enlarged-scale perspective views of a detail of the device of Figure 1, - Figure in 4 is a front elevation view of the detail of Figures 2 and 3, Figure 5 is a perspective view in partial cross-section of the detail of Figures 2 and 3. Preferred embodiment of the invention With reference to the cited figures, the label 1 indicates as a whole a device for supporting photovoltaic panels which are intended for electrical energy production plants, which device is produced in accordance with the present invention. The device comprises a stationary support structure in the form of a column support 2 capable of being fixed or anchored to the ground. By means of this support, the device 1 is therefore placed on and fixed to the ground, for example using screw-based anchorage means.

On the support 2, at the end opposite the end fixed to the ground, there is rotatably supported a toothed wheel 3, about an axis of rotation Z, by means of respective bearings that are not represented. The outer teeth of the wheel 3 are capable of meshing with a sprocket wheel 4, which in turn is rotationally secured with the output shaft 5 of a reduction gear 6, preferably with orthogonal axes, the input shaft 6a of which is rotationally coupled, by means of a corresponding gear, with the motor shaft 7 of an electric motor 8, the latter arranged to rotationally control the toothed wheel 3 by means of the abovementioned kinematic transmission, about the Z axis. Conveniently, the gearmotor unit 6-7 is fitted to a support bracket 8a secured to the support 2. The wheel 3 is in its turn secured to a support 9, which is therefore driven in an orientation movement about the Z axis, as a result of the rotation induced on the toothed wheel 3.

The support 9 conveniently comprises a plate-like base 9a, able to be secured to a side face of the toothed wheel 3, and from which a pair of shoulders 10 is erected equidirectionally. Between the shoulders 10 there is rotatably supported a shaft 11, about a rotation axis indicated by X, conveniently directed perpendicularly to the Z axis.

The shaft 11 is also arranged to support a chassis structure 12 intended to house photovoltaic panels, all indicated by the label 13, as described in detail below. The chassis 12 is bound rigidly to the shaft 11, for example by means of a secondary chassis 14 having a base 14a that can be bound to°the chassis 12, from which there is erected at right angles a pair of additional plate-like parts 15 capable of being fixed rigidly to the outer shell of the shaft 11. The chassis 12 comprises a plurality of longitudinal. and transverse sections (only partly represented in the drawings) appropriately connected to each other to form corresponding frames to house individual photovoltaic panel elements, the panels 13 being arranged to be coplanar with one another so as to define as a whole a solar radiation collecting surface having a substantially flat profile. Provision is also made for the point of fixing of the chassis 12 to the secondary chassis 14 to be located in such a position as to reduce or cancel out the unbalance of all the masses supported by the supports 2 and 9 in the orientation movement of the collecting surface about the X and Z axes. To control the rotation of the shaft 11 about the X axis in a first orientation motion of the collecting surfaces with respect to the incident direction of the light radiation, there is provided a first kinematic transmission comprising a motor 16, operatively connected to the shaft 11, to control the rotation of the latter. More specifically a reduction gear 17, with orthogonal shafts, is linked to the motor 16, the output shaft 17a of the reduction gear 17 being coaxially connected to the shaft 11. The input shaft of the reduction gear 17 is, on the other hand, rotationally coupled, by means of a corresponding gear, with the shaft of the motor 16, the latter therefore being arranged to rotationally control the collecting surface of the panels, by means of the abovementioned kinematic transmission, about the X axis. Conveniently, the gearmotor unit 16-17 is fitted on a support bracket 16b secured to the support 9.

The label 18 indicates a first braking means, conveniently chosen to be negative electromagnetic braking, which is provided in the kinematic chain between the motor 16 and the control shaft 11. It can be selectively activated to lock the shaft 11 in a preselected angular position, securing the shaft 11 with the structure of the support 9 of the device, in such a way as to discharge any stresses or vibrations on the support 9, protecting the motor 16 and the ^' kinematic coupling parts of the reduction gear 17. Conveniently, the brake 18 is chosen to be of the normally active type on the support shaft 11 and can be selectively disengaged from the shaft 11 by means of electrical power for the brake. A filter is therefore implemented by the brake 18 which provides total filtering of vibrations and/or stresses arising from external actions including those of a meteorological nature (for example arising from the action of the wind), this filter hence protecting the motor system 16-17 from local damage through accidental actions, from premature wear over time and, more generally, from phenomena of loosening or unscrewing of fixing elements provided on the device. According to a main feature of the invention, in the kinetic motion transmission chain between the motor 8 and the support 2, there is provided a corresponding second braking means labelled 20.

The braking means 20 is conveniently chosen to be a negative electromagnetic brake, and is designed to be able to be selectively activated to lock the support 9 in a preselected angular position, securing the support 9 with the stationary structure of the support 2 of the device, so as to discharge any stresses or vibrations on the support 2, protecting the motor 8 and the kinematic coupling parts of the reduction gear 6. Conveniently, the brake 20 is chosen to be of the normally active type on the support 9 and can be selectively disengaged from said support by means of electrical power for the brake. A filter is therefore implemented by the brake 20 which provides total filtering of vibrations and/or stresses arising from external actions including those of a meteorological nature (for example arising from the action of the wind), this filter hence protecting the motor system 6-7 from local damage through accidental actions, from premature wear over time and, more generally, from phenomena of loosening or unscrewing of fixing elements provided on the device.

In detail, the brake 20 comprises a first and a second part 20a, 20b, in relative rotation, the first part 20a secured to the support 9, the second part 20b secured to the support 2, there being provided between the parts respective friction surfaces to enable relative locking when the brake is actioned. Provision can also be made, in one or both kinematic chains relating to the motion transmissions in the orientation about the respective X and Z axes, for there to be placed between the brake 18 (or 20) and the shaft 11 (or the support 9) a resilient means with damping capability, for example implemented as a flexible coupling.

Although the invention relates to a device with control of the orientation on two distinct axes (X and Z), each provided with separate and distinct braking means (brakes 18 and 20), it is understood that the inventive concept can also be applied to other orientation axes, if provided, for example applied to a third orientation axis which is orthogonal with respect to the X and Z axes described above. Even on this additional axis, provision could therefore be made for a corresponding braking means in the corresponding kinematic chain provided for the orientation motion of the collecting surface about this axis. The invention thus solves the stated problem, achieving a number of advantages over the known solutions.

The main advantage lies in the fact that on each of the orientation axes of the collecting surface, the vibrations and/or stresses that have arisen from external actions including those of a meteorological nature (for example the wind) which act on the panels are strongly attenuated, if not actually cancelled out, protecting the motor system and the other kinematic elements of the transmission provided for each orientation axis from premature wear or localized damage, or preventing phenomena of loosening or unscrewing of the fixing elements due to the vibrations transferred to the device.

Claims

1. A device for supporting photovoltaic panels (13) which are intended for electrical energy production plants, comprising : at least one shaft (11) rotatably supported on a first support (9) about a first rotation axis (X), with respect to which the surfaces of the panels (13) collecting the light radiation are oriented, at least one chassis (12) arranged to house one or more of the photovoltaic panels (13), the chassis being rigidly bound to the first shaft (11) so that the collecting surfaces of the panels are oriented by means of rotation about the first axis (X), first motor means (16) operatively associated with the first support shaft (11) for controlling the rotation of the same about the first axis (X), there being provided in the kinematic transmission, between the first motor means and the first control shaft (11), first braking means (18), which can be selectively activated, to lock the first shaft (11) in a preselected angular position, at least a second stationary support (2) supporting the device, the first support (9) being rotatably supported on the second support about a second rotation axis (Z), - second motor means (8) operatively associated with the first support (9) for controlling the rotation of the same about the second axis (Z), characterized in that, in the kinematic transmission between the second motor means (8) and the first support (9), there are provided second braking means (20), which can be selectively activated, to lock the first support (9) in a preselected angular position securing the first support (9) with the stationary structure supporting the second support (2).

2. A device according to Claim 1, in which the second braking means comprise a negative braking element (20).

3. A device according to Claim 2, in which the braking element (20) comprises a normally active electromagnetic brake on the first support (9), which can be disengaged from the first support by means of electrical power for the brake.

4. A device according to one or more of the preceding claims, in which, in the kinematic transmission chain between the second braking means

(20) and the first support (9), there are, furthermore, interposed resilient damping means.