Device that automatically tracks the position of the sun

The present invention relates to a self-acting solar level tracking device for solar modules.

It is known to track solar modules (solar collectors, solar panels, etc.) to the position of the sun in order to allow an optimal irradiation with sunlight. It is usually desirable to have a perpendicular impact of sunlight on the plane of the solar module, which ensures the optimum energy yield. If this is not the case, that is to say, if the sun beams are at a lower angle or at a greater angle than 90 ° to the plane of the solar module, the energy yield is lower.

Since, depending on the time of the day, different angles of incidence of the sun's rays are present, the solar module must follow the sun's position. This can be performed manually, but this is cumbersome and time-consuming. However, self-acting sunbed tracking devices for solar modules are also known (see, for example, pressure step FR-2 798 718) in which the sun level is detected by a sensor, corresponding signals are generated as a function thereof and fed to a control unit Drive units corresponding to these signals for the solar module in order to move the latter into the optimum position relative to the sun.

The object of the present invention is to provide a self-acting solar level tracking device for solar modules which is characterized by a compact and robust construction with low maintenance requirements.

This object is achieved according to the invention by a self-acting solar level tracking device for solar modules having the features of claim 1.

With the sun tracking device according to the invention, it is possible to rotate one or more solar modules (solar collectors, solar panels) about a vertical axis and to pivot about a horizontal axis. As a result, the solar module or modules can be brought into a position in which the solar beams impinge substantially vertically on the plane of the modules so that an optimum energy conversion (in electrical current) can be achieved in this way. The movement of the solar module or of the solar modules takes place automatically as a function of the sun's position, whereby an optosensor detects the position of the sun, generates corresponding signals and supplies them to the control unit. The control unit controls the rotary and / or rotary drive,

The sun tracking device according to the invention can be attached to a stationary or a movable part. In a particularly preferred manner, it is used for fastening to a vehicle, for example a caravan or a mobile home, in particular on the roof thereof. The solar module or the solar modules can take over the power supply of the motorhome or caravan.

The sun tracking device according to the invention has a substructure for attachment to the stationary or movable part and a rotary plate which is rotatably mounted on the substructure and driven by means of a rotary drive. With the aid of the rotary drive, which is controlled by the control unit, the rotary actuator and thus the solar module or the solar modules are rotated around a vertical axis of rotation. On the turntable there is a swivel frame, which can be pivoted up and brought into the corresponding swivel position by means of a swivel drive. The solar module or the solar modules are attached to the swivel frame. The swivel frame can be moved from a position parallel to the turntable (with a swivel angle of 0 °) to a swung-out position of approximately 90 ° and back again.

In principle, the swivel frame has an element which is fixedly connected to the turntable and a swivel element which is pivotally mounted thereon and carries the solar module or the solar modules. It is essential that the pivoting drive, which is arranged in the end region of the element fixedly connected to the turntable, in the end region, in which the pivot bearing is provided between the two elements, essentially does not extend over the top of the element fixedly connected to the turntable In order to be able to arrange solar modules over the entire length of the elements, and overall a low overall height is achieved in which no mechanical parts protrude upwards in the collapsed state. As a result, the entire surface can be utilized over the elements for mounting solar modules, And small moments occur during pivoting. In addition, the wind forces acting on the device are thereby reduced, which is of particular importance when attaching the sun tracking device to the roof of a vehicle.

This desired compact design is achieved, in particular, by design and arrangement of the pivot drive. The rotary drive is mounted on the element fixedly connected to the rotary table transversely to its axis (longitudinal axis) and comprises a motor, a reduction gear and a gear drive shaft provided with a toothing, with which a sector gear wheel connected to the swivel element of the swivel frame meshes. The sector gear is designed and arranged in such a way that it does not project upward from the pivoting element. This would be the case with a normally formed full-circle gear.

When the motor (electric motor) of the rotary drive is actuated, its shaft is rotated. The gearbox used is used as a support, preferably in the ratio of 1: 180. The transmission output shaft therefore rotates much slower than the motor shaft and pivots the sector gear gear meshing with it and thus the pivoting element with the solar module (solar modules) attached thereto.

The sector gear preferably spans an arc of about 120 °, ie, a third circle. The desired pivoting of the pivoting element can thereby be achieved by at least 90 ° without the sector gear projecting upwards over the elements and making the mounting of solar modules impossible in this region.

In a further development of the invention, the pivoting element with a sector gear wheel is mounted so as to be pivotable between two elements which are fixedly connected to the rotary table. In this way, the swivel element with sector gear wheel is supported on both sides and thus a robust arrangement thereof. The motor, reduction gear and transmission output shaft are expediently mounted on two elements which are connected fixedly to the rotary table and which have the teeth of the transmission output shaft between them. This also achieves a robust design of the pivoting drive.

The element which is fixedly connected to the turntable and the pivoting element may, for example, be plate-shaped or rod-shaped or rod-shaped elements. The transverse extension of these elements is not restricted. In the normal case, the swivel frame extends laterally beyond the turntable. In a preferred embodiment, the elements are designed as rods, ie, the swivel frame comprises at least one rod connected rigidly to the turntable and at least one swivel bar. In a particular embodiment, the device comprises a total of four rods, which are fixedly connected to the turntable, of which the two outer members are each pivotally connected to a pivot rod and the two inner pivot arms pivotally connected to the sector gear.

The swivel frame, the rotary drive and the turntable thus form a unit which is rotatably mounted on the substructure. Preferably the turntable is rotatably mounted on the substructure by means of balls arranged in an annular groove.

The substructure preferably consists of a base plate, a housing arranged thereon, and a fixed plate arranged thereon for supporting the turntable. The annular groove is thereby arranged half in the fixed plate and in the rotary table. The floor plate can be connected, for example, to the roof of a vehicle (mobile home, caravan) by screwing, gluing, etc. In the housing arranged on the base plate, the rotary drive is advantageously accommodated, which has a motor (electric motor), a reduction gear and a drive screw, which meshes with a drive gear wheel for the rotary table. The drive gear is connected to a hollow hub which extends through the fixed plate and is connected to the turntable.

Suitable limit switches are provided for the rotary drive as well as for the rotary drive, which limit the rotational or pivot angle.

The optosensor is preferably arranged on the solar module (solar panel). The swivel frame preferably carries two solar panels, the upper of which carries the optosensor in the swivel position. The optosensor and the limit switches for the rotary drive and the rotary drive supply corresponding signals to a control unit (CPU), which drives the two motors for the rotary drive and the rotary drive, and is operatively connected to a control panel with display, which at least activates and deactivates the device manually And has, for example, a display with light-emitting diodes, which indicates the correct position of the device relative to the position of the sun.

With a simple and compact design, the optosensor enables a particularly accurate detection of the sun's level. It preferably has the following ingredients:<ul><li>A substructure,</li><li>A separating device arranged on the substructure, which divides the space above the substructure into a plurality of upper and laterally open compartments,</li><li>At least one light receiving means in each compartment which converts light into electrical current, and</li><li>Which are connected to the light receiving devices and lead to a control / evaluation / display unit.</li></ul>

This embodiment is based on the idea of ​​providing, with the separating device arranged on the substructure, a device which, depending on the position of the sun, provides shade which covers one compartment or several compartments and thus the at least one light receiving device arranged in each compartment. Depending on the state of the sun, therefore, the separation device can not produce any shadow at all when the sun is exactly perpendicular to the sensor and thus to the separating device, or else if there are otherwise uniform lighting conditions, such as at night, with diffuse light, etc., or the separation device Can cast shadows when their longitudinal axis forms an angle with the axis corresponding to the sun's position.

The electrical signals are fed to a control unit which, depending on the signals received, actuates the rotary drive and / or the rotary drive, which track the solar module relative to the sun's position, ie bring it into an optimum position with respect to the sun, Solar panel area). It is to be understood that the corresponding electrical signals are appropriately evaluated before they fulfill their control functions.

If, for example, the sensor, and thus the separating device, is aligned such that the axis of the sensor and of the separating device runs exactly parallel to the sunrays at the highest level of the sun (twelve o'clock noon), all the light receiving devices are in operation, Optimal sunshine. A movement of a corresponding solar module is therefore not necessary. If the angle of the solar radiation relative to the axis of the sensor now changes, the separating device shifts to one or more compartment shadows so that one or more light receiving devices are deactivated, which is indicated as explained above or leads to a tracking of the corresponding solar module , Until the optimum position is reached again.

Preferably, the separating device divides the space above the substructure into four compartments. It forms a so-called "shadow cross" with which particularly good results have been achieved with regard to the functional capability of the sensor.

A light-receiving device is expediently arranged in each compartment. This arrangement is sufficient to provide a sufficiently accurate indication and control.

A photodiode is preferably used as a light-receiving device.

In practice, an embodiment has proved particularly suitable, in which the sensor has a substructure which is approximately square in the horizontal section and a separating device with walls arranged along the diagonals of the substructure. The separation device thus forms a "shadow cross", which corresponds approximately to an Andreas cross in the horizontal section. Four triangular compartments are formed, each of which has a photodiode at a suitable distance from the walls of the shadow cross. The photodiodes are fixed to the substructure, the corresponding electrical lines being combined within the substructure and being led out of the substructure via an electrical cable . The cable is connected to a suitable control / evaluation / display unit.

In this case, the sensor is expediently provided for the solar module, which is arranged such that it can be rotated and pivoted, ie, it is also moved into the optimum position of the solar module relative to the sun. This means that the position of the sensor always corresponds exactly to the position of the solar module.

Generally speaking, if all the light receiving devices are illuminated in the same way (in the case of solar radiation, scattered light, at night), the associated control unit does not generate any commands for tracking the solar module. Control commands of this type are generated only if differences in brightness occur between the individual compartments (light receiving devices). If such a difference occurs, preferably both drives, ie the rotary drive and the rotary drive are driven (in a zigzag) in order to achieve a vertical sun position. Such a control unit is preferably provided with a device for the suppression of vibrations in order to avoid a permanent reciprocation of the drives.

The invention is explained in detail below with reference to an exemplary embodiment in conjunction with the drawing. Show it:<dl id="dl0001"><dt>FIG</dt><dd>A vertical section through a self-acting solar level tracking device for solar modules;</dd><dt>FIG</dt><dd>2 a top view of the housing of the device of FIG. 1 with the superstructure removed; FIG.</dd><dt>FIG</dt><dd>1 is a plan view of the device of FIGS. 1 and 2; FIG.</dd><dt>FIG</dt><dd>3 shows a detail view of a part of the pivot drive;</dd><dt>FIG</dt><dd>A schematic side view of an opto sensor for detecting the sun's position;</dd><dt>FIG</dt><dd>5 is a plan view of the sensor of FIG. 5; FIG. and</dd><dt>FIG</dt><dd>3 shows a block circuit diagram of a solar level tracking device in which the sensor of FIGS. 5 and 6 is used.</dd></dl>

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The self-acting solar level tracking device for solar modules shown in FIG. 1 has a substructure which consists of a base plate 1, a housing 2 and a plate 3 arranged on the housing. On the substructure is rotatably mounted a turntable 4 which carries a pivoting frame 31 on which two solar panels 13 are fastened. These solar panels 13 convert sunlight into electric current, which can serve, for example, to supply a vehicle on whose roof the device is arranged.

For attaching the device, the base plate 1 is glued or screwed to the roof of the vehicle. Depending on the signals generated by an optosensor 14, which is arranged on the top solar panel 13 in the figure, a rotary drive for rotating the rotary switch 4 and a pivoting drive for pivoting the pivoting frame 31 up and down are actuated in order to ensure an optimum state of the solar panels 13 To the sun (vertical incidence of the sun rays on the panel plane).

In the housing 2 arranged on the base plate 1, the rotary drive is provided for rotating the rotary switch 4. The rotary drive comprises an electric motor 16, a reduction gear 15 and a driving screw 9 arranged along an axis. The worm 9 meshes with a drive gear wheel 8, which is fixedly connected to a hollow hub 7. The hollow hub extends upwards through the permanently installed plate 3 and is fixedly connected to the rotary plate 4. A rotation of the drive sprocket 8, which is produced by the drive screw 9, thus causes a rotation of the rotary actuator 4. The rotary disk 4 is mounted on the fixed disk 3 via balls 5, the balls being accommodated in an annular groove 6 which extends in half in both plates 3, 4.

The rotation of the drive gear 8 is limited by limit switches 18 with which a lever 17, which is guided by way of a mandrel, is guided in a worm groove which is located on the underside of the drive gear wheel 8. The drive gear 8 can therefore rotate through stop rotation from 370 to 370 °.

Furthermore, a box 10 is arranged in the housing 2 and receives a control unit 10 which controls the rotary drive and the rotary drive and which are supplied with the signals corresponding to the limit switches of the rotary drive and the rotary drive as well as by the optosensor. Furthermore, the control unit 10 is connected to a control panel with display. The corresponding electrical lines for this are not shown.

The pivoting drive for pivoting up and pivoting the pivoting frame 31 is shown schematically at 30 in FIG. A more detailed description of the pivot drive follows in conjunction with FIGS. 3 and 4.

When a signal from the optosensor 14 is fed to the control unit 10, which requires the device to be tracked by a rotary movement of the rotary switch 4, the motor 16 is controlled by the control unit 10. The motor output shaft is thereby caused to rotate. Via the transmission 15, a corresponding adjustment takes place so that the drive screw 9 has a substantially lower rotational speed. The drive worm 9 drives the drive gear 8 in the selected direction. Its rotation results in a rotation of the rotary switch 4 in the extent determined by the control of the control unit or the limit switch 18. The turntable 4 is rotated back and forth until it assumes the optimum rotational position for the sun.

FIG. 3 shows a plan view of the rotary table 4 on which the swivel frame 31 is fastened. The two solar panels 13, which are fixed to the bogie 31, are shown only in dashed lines.

The bogie has two outer pivot rods 13 which are each articulated to a rod 11 fixedly connected to the turntable 4, as shown at 32. Furthermore, the bogie has a third, approximately center-arranged pivot rod 20, which is connected to the pivot drive and is thus pivoted. Their pivoting movement is transmitted via the solar panel 13 to the two outer pivot rods 13. The central pivot rod 20 is articulatedly connected to two inner rods 19, which are fixedly connected to the rotary plate 4.

A total of seven rods are thus provided, namely three pivot rods and four fixed rods. The two solar panels 13 are attached to the three pivot rods 13 and 20.

The center pivot rod 20 is also connected to a sector gear 25, which corresponds to about one third circle. This sector gearwheel 25 and also the further parts of the pivoting drive do not project beyond the tops of the pivoting rods, so that the solar panels can cover the pivoting drive and can extend over the entire length of the pivoting rods. As a result, in the collapsed state of the swivel frame, no parts protrude above the bar, and solar panels with the largest possible surface area can be installed.

As shown in the detail view of FIG. 4, sector sector gear 25 meshes with the toothing of a transmission output shaft 26 of the pivot drive. By rotating the shaft 26, the rod 20 is pivoted up and down, whereby the solar panels are brought into the optimum position relative to the sun. The transmission output shaft 26 extends from a reduction gear 22, which is connected via a further reduction gear 23 to a drive motor (E-motor) 24. The motor 24, the two reduction gears 23 and 22, and the transmission output shaft 26 are arranged along an axis. The entire drive is flanged to the fixed rod 19, as shown at 21. The transmission output shaft is supported on the two fixed rods 19 via suitable bearing blocks (not shown).

If the swivel motor 24 is controlled by the control unit 10, its output shaft is made to rotate. A reduction of about 1: 180 is achieved via the two reduction gears 23 and 22, resulting in a reduced rotational movement of the geared transmission output shaft 26. This meshes with sector sector gear 25 and in this way pivots pivot arm 20 and thus solar panel 13 into the desired pivot position. Reverse pivoting takes place in the opposite direction. Suitable limit switches are also provided here, which limit the pivoting movement of the pivoting frame.

According to the invention, a self-acting sun level tracking device for solar modules is described, which due to its mechanical drive is largely maintenance-free and very compact. Large-area solar panels can thus be arranged, and the device produces only small wind forces. A low overall height is achieved. The device is particularly robust.

The optosensor shown in FIGS. 5 and 6 has a substructure 100, which is schematically shown here as a corresponding base. This subassembly is hollow in order to receive corresponding wirings. It has a cable version on its underside. In this embodiment, the substructure is approximately square in the horizontal section.

On the substructure 100, a separation device 200 is arranged, which in the horizontal section is in the form of an Andreask cross. The separation device 200 forms four horizontally cut triangular compartments 160, which are open upwards and sideways. Sunlight can penetrate these compartments from above and from the side. The two other sides of the triangle, which correspond to the sub-building gondolas, are occupied by the walls 600 of the separation device 200, thus shielding the respective compartment from sunlight.

A light receiving device 300 in the form of a photodiode is located in each compartment at a suitable distance from the separating device 200. When irradiated with sunlight, the photodiode 300 generates electrical signals which are supplied to an appropriate control unit via electrical conductors 400, which are combined in an electrical cable 500.

The separation device 200 has a suitable height so as to allow a shadow projection of the separating device 200 to one or more compartments, and thus the light receiving devices 300 arranged there, when the sun is tilted relative to the vertical axis of the sensor. The exact height can be determined empirically.

FIG. 7 shows the sensor of FIGS. 5 and 6 as part of a sun tracking device. The sensor is indicated here at 800 and is located on the solar module which can be rotated and pivoted. The corresponding signals from the sensor 800 are fed to a control unit 700 (central unit, CPU), which likewise receives signals from the switches 900, 1000 of the rotary drive and the rotary drive, evaluates the received signals and outputs control command signals corresponding to the rotary drive 110 as well as the rotary drive 120. Further, the control unit 700 supplies signals to a display / operation unit 130. This unit has a display panel 140 and an on / off switch 150.

The totalizer functions as follows:

The user turns on the device with the switch 150. The sensor 800 detects the level of the sun and supplies corresponding signals to the control unit 700. These signals are displayed in the display field 140. Furthermore, if necessary, corresponding command signals are generated which are fed to the rotary drive 110 and / or the rotary drive 120, which effect a tracking of the solar module. The provided end switches 900, 1000 terminate the corresponding movements of the solar module.