WO2011131402A2

WO2011131402A2 - Sensor device and device for converting sunlight into another form of energy

Info

Publication number: WO2011131402A2
Application number: PCT/EP2011/053099
Authority: WO
Inventors: Volker Schulmayer; Kai Heinrich; Florian Klein
Original assignee: Zf Friedrichshafen Ag
Priority date: 2010-04-21
Filing date: 2011-03-02
Publication date: 2011-10-27
Also published as: WO2011131402A3; DE102010028027A1

Abstract

The invention relates to a sensor device (2) for capturing the reflected sunlight from a plurality of movable mirrors (1, 1', 1'') of a device for converting sunlight into another form of energy, wherein by means of a tracking device (4) the mirrors (1, 1', 1'') track the position of the sun so that said mirrors jointly reflect the sunlight onto a converter device (3) which converts the sunlight into the other form of energy. The invention further relates to a device for converting sunlight into another form of energy. According to the invention, for each of the mirrors (1, 1', 1'') the sensor device (2) has a first and a second sensor aperture (2b, 2c, 2b', 2c', 2b'', 2c'') associated with said mirrors (1, 1', 1'') and a respective light-sensitive sensor (2d) recessed in said aperture.

Description

Sensor device and device for converting sunlight

into another form of energy

The invention relates to a sensor device for detecting the reflected sunlight of a plurality of movable mirrors of a device for converting sunlight into another form of energy, in which the mirrors are tracked by means of a tracking device so the sun, that these together the sunlight on a transducer device which the Sunlight into the other form of energy converts, reflect. Such a sensor device is used for optimal alignment of the mirror on the converter device according to the current state of the sun in the sky (position of the sun).

Furthermore, the invention relates to a device for converting sunlight into another form of energy, with a plurality of movable mirrors, with a converter device and with a sensor device arranged between the mirrors and the converter device. In this case, the mirrors are tracked to the position of the sun so that they reflect the sunlight together on the converter device, which converts the sunlight into the other form of energy.

The converter device converts the incident (or reflected) from the (sunlight) light, for example, into electrical energy or heat energy and can accordingly be designed, for example, as a fluid conduit system for heating the fluid or as a photovoltaic element for generating electrical power.

Such a sensor device and such a device for converting sunlight into another form of energy is known from DE 10 2008 008 403 A1. The sensor device proposed here or the device proposed here for converting sunlight into another form of energy uses a linear photodiode array per mirror in order to align the orientation of the mirrors as precisely as possible with intensity distributions of the reflected sunlight to capture on the photodiode arrays. The device thus requires a complicated evaluation of the intensity distributions.

A simple sensor device with only two photosensitive sensors for tracking a solar device, for example a mirror, according to the position of the sun is disclosed in DE 10 2006 010 419 A1. This sensor device provides for a vertical alignment of the solar device to the light incident on the solar device, whereby this sensor device is not suitable for aligning a plurality of mirrors on a common focal point or a common transducer device.

A first object is therefore a sensor device for a device for converting sunlight into another form of energy, in which the mirrors are tracked by means of a tracking device so that they reflect the sunlight together on a transducer device, which is simple in construction and no elaborate sensor data evaluation needed. Another object is to provide a device for converting sunlight into another form of energy, which also has these advantages.

The first object is achieved in that the sensor device for each of the mirrors has a first and a second sensor opening associated with this mirror and in each case a light-sensitive sensor recessed therein. In this case, a depth in which the sensors are recessed in the sensor openings is greater than a height or a width of the sensor openings.

Due to the recessed arrangement of the photosensitive sensors in the sensor openings, only the reflected light of the respectively associated with these sensor openings mirror can fall. In the case of misalignment of a mirror, the sunlight reflected thereby can thus not interfere with the other sensor openings or the light-sensitive sensors recessed therein. In addition, only two light-sensitive sensors are Direction of the respective mirror necessary, which simplifies both the effort to evaluate the sensor data, as well as the mechanical structure of the sensor device. The evaluation of the sensor data, or the tracking of the mirror can be done for example via a two-point controller or a threshold switch. By using such a sensor device, it is also not necessary to provide position sensors for the mirrors or to determine the current position of the sun on the basis of tabular data, the time of day, the date and the spatial position.

In order to minimize disturbing effects of stray light, the inner walls of the sensor openings are preferably matt, in particular matt black, whereby light reflections within the sensor openings are significantly reduced and incident stray light can not or only to a slight extent penetrate to the photosensitive sensors.

At least one of the photosensitive sensors is designed in particular as a photodiode or CCD or CMOS sensor. In order to reliably detect the light reflected by the mirrors even in the case of a cloudy sky or in fog, this photosensitive sensor is preferably designed as an infrared photodiode.

In a development of the invention, a one-part or multi-part sensor housing is provided which has a convexly curved surface in which the sensor openings are arranged. This surface is preferably aligned in the direction of the mirror. Thus, the sensor housing may be designed, for example, half-round, wherein the sensor openings are arranged in the rounding and aligned in the direction of the mirror, that is, the open sides of the sensor openings point in the direction of the respective mirror. The space required for the sensor device space requirement can be optimized thereby.

In another embodiment of the invention, a one-piece or multi-part sensor housing is provided, which has a straight, that is not curved surface in which the sensor openings are arranged, whereby the sensor housing simple and inexpensive to produce. For example, the sensor housing can be designed in the shape of a bar or cuboid.

The sensor openings are designed in particular bore-like or slot-like, whereby the sensor openings are simple and inexpensive to produce, for example, by a machining of the sensor housing, in which the sensor openings are arranged.

The further object is achieved by a device for converting sunlight into another form of energy, with a plurality of movable mirrors, with a converter device and with the sensor device according to the invention described above. In the device for converting sunlight, the mirrors are tracked by means of a tracking device so that they reflect the sunlight together on the converter device, which converts the sunlight into the other form of energy. In this case, the sensor device is arranged between the mirrors and the converter device, and the sensor openings associated with a mirror are oriented in the direction of this mirror such that the sunlight reflected by this mirror passes through these sensor openings onto the photosensitive sensors recessed therein.

Preferably, the sensor openings are aligned with the mirrors such that sunlight reflected from the respective mirror only penetrates through both sensor openings to the photosensitive sensors when the mirror is optimally aligned with the converter device. In a less optimal orientation, the two sensors are then irradiated with different intensities, or only one of the two sensors is directly irradiated by the reflected sunlight, and in poor alignment, neither of the two sensors is irradiated directly. If none of the sensors are irradiated directly, a search may be performed in which the mirror moves all or part of its trajectory until both sensors are again irradiated by the reflected sunlight. If the sensors are irradiated with different intensities , the respective mirror can be moved in the corresponding direction depending on which of the sensors is irradiated more intensively or less intensively until both sensors are irradiated again with the same intensity.

The search, if none of the sensors is directly irradiated, is preferably carried out in dependence on the time of day and / or weather data, which excludes that the mirror unnecessary in the dark or in bad weather (heavy clouds, fog, rain, snow, etc. ) are moved. The trajectory of the mirror during the search is preferably limited depending on the current time and optionally additionally depending on the current date, whereby only the part of the total possible trajectory is traversed, in which at this time is most likely the optimal orientation of the mirror.

In order to reliably detect optimum alignment of the mirrors with the transducer device, the first of the sensor apertures associated with one of the mirrors is directed towards a first edge region of this mirror and the second of the sensor apertures associated with this mirror is directed toward a second edge region of this mirror, such that the sunlight reflected from the first edge region of the mirror passes through the first sensor opening onto the first photosensitive sensor recessed therein, and the sunlight reflected from the second edge region of the mirror passes through the second sensor opening onto the second photosensitive sensor recessed therein. In particular, a longitudinal axis of the sensor opening extending between a light incidence opening of the sensor opening and the photosensitive sensor in each case extends through the edge region of the mirror assigned to this sensor opening.

The mirrors of the device for converting sunlight into another form of energy are tracked in particular by pivoting about substantially vertical pivot axes of the sun, so follow the sun's position by a pivoting movement between an east and west orientation (orientation in azimuth). Alternatively or additionally, the mirrors are adjusted by pivoting. ken are tracked to substantially horizontal pivot axes of the sun, so follow the sun's position by a pivoting movement between a horizontal and vertical orientation (orientation in elevation). The sensor openings are then preferably slit-like with a substantially rectangular cross-section, wherein longer sides of the cross-sections extend parallel to the pivot axes of the mirror.

In the following the invention will be explained in more detail with reference to figures, from which further advantageous embodiments can be taken. The figures show in schematic representation:

Fig. 1 is a two-dimensional view of a device for converting sunlight into another form of energy;

Fig. 2 is a three-dimensional view of a device for the conversion of

Sunlight into another form of energy.

The device shown in Fig. 1 for converting sunlight into another form of energy has three movable mirrors 1, 1 ', 1 ", each with a concave reflection surface, a sensor device 2, a transducer device 3 and a tracking device 4, wherein the sensor device 2 stationary with respect to the converter device 3. Mirrors 1, 1 ', 1 ", sensor device 2 and converter device 3 extend perpendicularly beyond the plane of the drawing, the sensor device 2 having a smaller extent perpendicular to the plane of the drawing than the mirrors 1, 1', 1". and the converter device 3. The sensor device 2 is thus arranged only in a small area in relation to the overall extent between the mirrors 1, 1 ', 1 "and the converter device 3. In this case, the sensor device 2 is preferably arranged in the immediate vicinity of the converter device 3 or at least closer to the converter arrangement 3 than to the mirrors 1, 1 ', 1 "in order to minimize the space requirement of the sensor device 2. The sensor device 2 preferably surrounds , or a sensor housing 2a of the sensor device 2, the transducer device 3, as shown, along a the converter device 3 extending circular or elliptical section. For this purpose, the sensor housing 2a of the sensor device 2 has a first surface facing the transducer device 3 and a first curved surface facing the mirrors 1, 1 ', 1 "and a convexly curved second surface, in which sensor openings 2b, 2c, 2b', 2c ', 2b ", 2c" are arranged.

The reflection surfaces of the mirrors 1, 1 ', 1 "reflect the sunlight shining on the mirrors 1, 1', 1" from the sun 5 onto the sensor device 2 and onto the converter device 3, which transmits the light into another form of energy, for example electrical energy or heat energy, converts. The mirrors 1, 1 ', 1 "are aligned in the orientation shown to the transducer device 3 so that the sun 5 shown a maximum of reflected sunlight hits the transducer device 3. In the course of the movement of the sun 5 over the sky (see from the sun 5 outgoing arrow), however, the angle of incidence of sunlight on the mirror 1, 1 ', 1 "changes, so they must be tracked to the sun, in order to continue to reflect a maximum of sunlight on the transducer device 3. For this purpose, the tracking device 4 has on the mirrors 1, 1 ', 1 "arranged adjusting devices 4a, which track the mirrors 1, 1', 1" the sun's position by a pivoting movement about the perpendicular to the plane extending pivot axes 4b. Depending on the design of the device for converting sunlight into another form of energy, in this case the pivot axes 4b can extend vertically or horizontally. In order to detect a misalignment or an optimal alignment of the mirrors 1, 1 ', 1 "to the converter device 3, the tracking device 4 evaluates sensor signals of the sensor device 2 and, based thereon, carries out a reorientation or tracking of the mirrors 1, 1', 1" ,

The sensor housing 2a has for each mirror 1, 1 ', 1 "two slot-shaped sensor openings 2b, 2c, 2b', 2c ', 2b", 2c "in which each deepened a light-sensitive sensor 2d is arranged on the optimal orientation or the Misalignment of the respective mirror 1, 1 ', 1 "to the converter device 3 can be seen. The sensor openings 2b, 2c, 2b ', 2c', 2b ", 2c" have rectangular cross sections; encryption Extensions of longitudinal axes of the sensor openings 2b, 2c, 2b ', 2c', 2b "meet at the center of the converter device 3.

The orientation of the sensor openings 2b, 2c, 2b ', 2c', 2b ", 2c" to the mirrors 1, 1 ', 1 "will now be explained by way of example with reference to the first mirror 1 and the sensor openings 2b, 2c associated with this mirror 1. The orientation of the further sensor openings 2b ', 2c', 2b ", 2c" to the respective further mirrors 1 ', 1 "is analogous.

The first sensor opening 2b is oriented in the direction of a first edge region 1a of the mirror 1 such that the sunlight reflected by this first edge region 1a passes through the first sensor aperture 2b on the photosensitive sensor 2d which is recessed therein with optimum alignment of the mirror 1 While the second sensor opening 2c is oriented in the direction of a second edge region 1b of the mirror 1, the sunlight reflected by this second edge region 1a is at an optimal alignment of the mirror 1 to the sun 5 through this second sensor opening 2c recessed arranged photosensitive sensor 2d falls. The longitudinal axes of the two sensor openings 2b, 2c thus run substantially parallel or coaxial with the light beams reflected from the respective edge regions 1a, 1b.

It must be noted that the mirrors 1, 1 ', 1 "track the position of the sun by pivoting movements and, accordingly, the positions of the edge regions 1 a, 1 b, 1 a', 1 b ', 1 a", 1 b "in FIG The sensor openings 2b, 2c, 2b ', 2c', 2b ", 2c" must therefore be designed in such a way that that of the edge regions 1 a, 1 b, 1 a ', 1 b ', 1 a ", 1 b" regardless of their position on the photosensitive sensors 2 d falls, for example, by the sensor openings 2 b, 2 c, 2 b', 2 c ', 2 b ", 2 c" starting from the photosensitive sensors 2 d in the direction of the mirror 1, 1 ', 1 "(slightly) widen. As a result, the photosensitive sensors 2 d always have direct "visual connections" through the respective sensor openings 2b, 2c, 2b ', 2c', 2b ", 2c" through to the respective edge regions 1 a, 1 b, 1 a ', 1 b', 1 a ", 1 b".

As indicated in FIG. 1 by the light rays emanating from the sun 5 and illustrated as dashed lines, the alignment of the sensor openings 2b, 2c, 2b ', 2c', 2b ", 2c" with the mirrors 1, 1 ', 1 "only the light reflected from the respective edge region 1 a, 1 a ', 1 a" and 1 b, 1 b', 1 b "through the respective sensor opening 2b, 2c, 2b ', 2c', 2b", 2c " up to the light-sensitive sensors 2d recessed therein penetrate, whereby the sensor device 2 is very robust with respect to stray light disturbances, whereby the more optimally one of the mirrors 1, 1 ', 1 "is aligned with the transducer device 3, more of it penetrates A misalignment of one of the mirrors 1, 1 ', 1 "is recognized by the tracking device 4 in that the two are assigned to a mirror 1, 1', 1" light-sensitive sensors 2d different intensities of ref sunlight are irradiated, which is concluded on the basis of these intensity differences on the direction in which the respective mirror 1, 1 ', 1 "the sun's position must be tracked in order to align it optimally to the converter device 3.

Fig. 2 shows a device for converting sunlight into another form of energy in three-dimensional view, which is carried out according to the device for converting sunlight into another form of energy of Fig. 1. Identical components / elements are therefore provided with the same reference numerals. For the sake of simplicity, only one of a plurality of mirrors 1 is shown here and the converter device 3 is shown in section.

As is apparent from Fig. 2, the transducer device 3 is formed as a fluid-filled tubular conduit system for heating this fluid. The sensor device 2 is arranged semicircularly around the converter device 3 between the latter and the mirror 1 (or the mirrors), but only within a small region of the longitudinal extent of the converter device 3. The sensor openings 11 have rectangular cross sections, longer sides of the device cross sections parallel to a longitudinal axis 3a of the transducer device 3 and parallel to the pivot axis 4b of the mirror 1 (or the pivot axes of the mirror).

REFERENCE CHARACTERS

1 first mirror

V second mirror

1 "third mirror

1 a first edge region of the first mirror 1

1 b second edge region of the first mirror. 1

1 a 'first edge region of the second mirror 1'

1 b 'second edge region of the second mirror 1'

1 a "first edge area of the third mirror 1"

1 b "second edge region of the third mirror 1"

2 sensor device

2a sensor housing

2 b first sensor opening of the first mirror 1

2c second sensor opening of the first mirror. 1

2b 'first sensor opening of the second mirror 1'

2c 'second sensor opening of the second mirror 1'

2b "first sensor opening of the third mirror 1"

2c "second sensor opening of the third mirror 1"

2d photosensitive sensor

2e light incidence opening

3 converter device

3a longitudinal axis of the converter device 3rd

4 tracking device

4a tracking device

4b pivot axes of the mirrors 1, 1 ', 1 "

5 sun

Claims

claims

1 . Sensor device (2) for detecting the reflected sunlight of a plurality of movable mirrors (1, 1 ', 1 ") of a device for converting sunlight into another form of energy, in which the mirrors (1, 1', 1") are adjusted by means of a tracking device (4 ) are tracked so that they reflect the sunlight together on a transducer device (3), which converts the sunlight into the other form of energy, characterized in that the sensor device (2) for each of the mirrors (1, 1 ', 1 ") has a first and a second sensor opening (2b, 2c, 2b ', 2c', 2b", 2c ") associated with said mirror (1, 1 ', 1") and in each case a photosensitive sensor (2d) recessed therein.

2. Sensor device (2) according to claim 1, characterized in that a sensor housing (2a) is provided with a straight surface or a convexly curved surface in which the sensor openings (2b, 2c, 2b ', 2c', 2b ", 2c ") are arranged.

3. Sensor device (4) according to claim 1, characterized in that the sensor openings (2b, 2c, 2b ', 2c', 2b ", 2c") are boring or slot-like.

4. Sensor device (4) according to claim 1, characterized in that at least one of the photosensitive sensors (2d) is designed as a photodiode, in particular infrared photodiode, or CCD or CMOS sensor.

A device for converting sunlight into another form of energy, comprising a plurality of movable mirrors (1, 1 ', 1 "), a transducer device (3) and the sensor device (2) according to one of claims 1 to 4, wherein the mirrors (1, 1 ', 1 ") are tracked by means of a tracking device (4) so that they reflect the sunlight together on the transducer device (3), which converts the sunlight into the other form of energy; wherein the sensor device (2) between the mirrors (1, 1 ', 1 ") and the converter Device (3) is arranged and in each case one of the mirrors (1, 1 ', 1 ") associated sensor openings (2b, 2c, 2b', 2c ', 2b", 2c ") in the direction of this mirror (1, 1', 1 "), the sunlight reflected by this mirror (1, 1 ', 1") passes through these sensor openings (2b, 2c, 2b', 2c ', 2b ", 2c") onto the photosensitive sensors recessed therein (2d) falls.

6. Apparatus for converting sunlight into another form of energy according to claim 5, characterized in that the first one of the mirrors (1, 1 ', 1 ") associated sensor openings (2b, 2b', 2b") in the direction of a first edge region (1 a, 1 a ', 1 a ") of this mirror (1, 1', 1") is directed and the second of said mirror (1, 1 ', 1 ") associated sensor openings (2c, 2c', 2c" ) in the direction of a second edge region (1 b, 1 b ', 1 b ") of this mirror (1, 1', 1") is directed, so that from the first edge region (1 a, 1 a ', 1 a " ) reflects sunlight through the first sensor opening (2b, 2b ', 2b ") onto the photosensitive sensor (2d) recessed therein, and the sunlight reflected from the second edge area (1b, 1b', 1b") passes through the second Sensor opening (2c, 2c ', 2c ") on the recessed therein arranged photosensitive sensor (2d) falls.

7. Apparatus for converting sunlight into another form of energy according to claim 5, characterized in that the mirrors (1, 1 ', 1 ") by

Pivoting about substantially vertical pivot axes (4b) track the position of the sun.

8. A device for converting sunlight into another form of energy according to claim 5, characterized in that the mirror (1, 1 ', 1 ") by

Pivoting about substantially horizontal pivot axes (4b) track the position of the sun.

9. A device for converting sunlight into another form of energy according to claim 7 or 8, characterized in that the sensor openings (4a, 4b) are slot-like, with substantially rectangular cross-sections and the longer sides of the cross-sections parallel to the pivot axes (4b) ,