WO2022117825A1

WO2022117825A1 - Arrangement and method for detecting radiation

Info

Publication number: WO2022117825A1
Application number: PCT/EP2021/084192
Authority: WO
Inventors: Johannes Christoph Sattler; Iesse Peer SCHNEIDER; Cristiano José Teixeira Boura; Markus Sauerborn; Joachim GÖTTSCHE
Original assignee: Fh Aachen
Priority date: 2020-12-04
Filing date: 2021-12-03
Publication date: 2022-06-09
Also published as: EP4256250A1

Abstract

The invention relates to an arrangement (1) for detecting radiation, comprising: a radiation receiver (2) that has a receiving region (3) for receiving radiation (4); a plurality of objects (6) arranged inside an object field (5) for reflecting and/or emitting radiation (4) onto the receiving region (3) of the radiation receiver (2); a camera arrangement (8) comprising a plurality of cameras (9), wherein the cameras (9) are each provided with a lens for detecting the radiation; and a movement device, wherein the movement device is designed to transfer the camera arrangement (8) from a rest position into a capturing position and from the capturing position back into the rest position. In the rest position, the cameras (9) are arranged such that the lenses thereof are outside the receiving region (3) and therefore radiation originating from the objects (6) cannot be detected by means of the cameras (9). In the capturing position, the cameras (9) are arranged such that the lenses thereof are inside the receiving region (3) and therefore radiation originating from the objects (6) can be detected by means of the cameras (9). The cameras (9) are designed and configured such that, in the capturing position, the entire object field (5) can be detected thereby. This makes it possible to provide an arrangement (1) for detecting radiation by means of which the entirety of an object field (5) can be detected.

Description

Arrangement and method for detecting radiation

The invention relates to an arrangement for detecting radiation, with a radiation receiver having a receiving area for receiving radiation, a plurality of objects arranged within an object field for reflecting and/or emitting radiation onto the receiving area of the radiation receiver and one attached to a movement device and one Camera array having a plurality of cameras.

Such arrangements are used, for example, in solar tower power plants. Solar tower power plants are power plants that use solar radiation as the primary energy source and convert it into thermal energy through absorption by a radiation receiver. In solar tower power plants, the direct radiation of the sun is bundled by reflectors, the so-called heliostats, onto a small radiation receiver surface located on a solar tower. Such solar tower power plants achieve shorter energetic amortization times and, depending on the design, higher efficiencies than photovoltaic systems, which also use solar radiation as an energy source.

A major technical challenge in solar tower power plants is that the heliostat field consists of dozens to thousands of individual heliostats that have to be individually tracked to the position of the sun very precisely so that the reflected direct solar radiation is as evenly distributed as possible or hits the reception area of the radiation receiver according to a target point strategy. Depending on the quality of the tracking mechanism, there may be major inaccuracies in the tracking, which means that solar radiation still misses the reception area of the radiation receiver and therefore part of the radiation power provided by the heliostat field can no longer be converted into heat by the reception area of the radiation receiver . But unwanted beam distributions on the absorber with high hotspots or beam sinks are also problematic. Both of these have a negative impact on the overall efficiency of the solar tower power plant and result in less energy being generated. This in turn leads to lost profits for the power plant operator. Conventionally, heliostats are calibrated one after the other using a calibration surface that serves as a reference below the receiving area onto which they shine with the reflected sunlight. Due to the large number of heliostats and the associated high expenditure of time, the calibration is typically only carried out a few times a year for each individual heliostat. Therefore, during the operation of the solar tower power plant, there is usually no feedback as to whether a single heliostat hits its target point in the reception area with sufficient accuracy. A precise, simple but also rapid measurement of the orientation of all heliostats with a single analysis and position correction of the mirrors at one, hundreds or thousands of measurement times during solar operation represents a technical challenge.

Specifically, WO 2015/117192 A1 describes a device for monitoring and measuring a plurality of light sources, in particular heliostats. The device includes several cameras arranged in a row. To record the heliostats, the heliostat field is scanned with the camera row. For this purpose, the camera row is moved along the reception area of the solar tower and several images of the heliostat field are recorded in different positions of the camera row. The heliostats can then be aligned using these images.

In the devices known from the prior art, however, disruptive factors such as the movement of the heliostats due to wind influences, for example in methods with sequential image recordings, can lead to a deterioration in the image recordings or to incorrect evaluation and alignment of the heliostats. If a heliostat moves between two image recordings, this movement cannot be detected and not taken into account in the evaluation of the images, so that the heliostat is incorrectly positioned.

Proceeding from this, it is the object of the invention to provide an arrangement for detecting radiation, with which an object field can be detected completely and simultaneously. This object is solved by the subject matter of patent claim 1. Preferred developments can be found in the dependent claims.

According to the invention, an arrangement for detecting radiation is provided, with a radiation receiver having a receiving area for receiving radiation, a plurality of objects arranged within an object field for reflecting and/or emitting radiation onto the receiving area of the radiation receiver, a camera arrangement having a plurality of cameras , wherein the cameras are each provided with a lens for capturing the radiation, and a movement device, wherein the movement device is designed to transfer the camera arrangement from a stationary situation to a recording situation and from the recording situation back to the stationary situation, the cameras in the resting position are arranged in such a way that their lenses are outside the reception range, so that the cameras cannot detect any radiation originating from the objects, the cameras are arranged in the recording position in such a way that their objects are ive are located within the reception area, so that radiation originating from the objects can be detected with the cameras, and the cameras are designed and set up in such a way that the entire object field can be detected with them in the recording situation.

If it is stated here that the radiation receiver has a reception area for receiving radiation, then “reception area” means the area to which radiation is applied by the objects in their intended operating positions, eg according to target point strategies. However, the invention does not require that the radiation receiver be provided with devices in the entire reception area with which the radiation can be received. Rather, it is the case that the radiation receiver can also consist of an arrangement of a plurality of devices with which the radiation can be received, with at least small distances and/or gaps between these devices, on which the radiation originating from the objects impinges, in which, however, no radiation is detected by the radiation receiver. In addition, if there is a defect in an object that is no longer in its intended operating state, it can of course happen that the radiation from this object does not fall on the receiving range of the radiation receiver. Such a situation is possible, for example, because the object is incorrectly oriented. In such a In this situation, of course, the area into which the object then erroneously radiates does not belong to the reception area of the radiation receiver in the sense of the present invention.

The arrangement can also be constructed in such a way that the reception area extends over 360° along the radiation receiver and the object field is also arranged in 360° around the radiation receiver. The camera arrangement moved by the movement device is then designed in such a way that it extends over 360°, so that a plurality of cameras, which are arranged all around the radiation receiver, can capture the entire object field.

It is therefore a crucial point of the invention that, due to the camera arrangement, the entire object field can be recorded in just one position of the camera arrangement. This enables simultaneous image recording of the entire object field by the majority of cameras. If there is talk of detecting the entire object field, this means in particular that the radiation reflected by the object field in the direction of the radiation receiver can be detected. It is therefore no longer necessary to move the cameras over the reception range of the radiation receiver during an image recording process and to record images sequentially. Rather, the simultaneous image recordings of the entire object field according to the invention result in the influence of potential disruptive factors on the quality of the recorded images and thus on the resulting positioning of the heliostats being reduced.

If the camera arrangement is moved into the reception area, it can detect the radiation there. If it is moved out of the reception area, it does not interfere with the detection of the radiation by the radiation receiver, for example by covering parts of the radiation receiver. Because the cameras are designed and set up in such a way that the entire object field can be captured with them in the recording situation, the camera arrangement in particular does not have to be moved in order to be able to capture all objects in the object field. This means that all objects in the object field, such as mirrors or mirror facets of heliostats, can be captured by each camera at the same time, i.e. simultaneously. Industrial cameras are preferably used as cameras. Industrial cameras are used for simple monitoring tasks and for metrological tasks for quality control using image processing. They are characterized by their robustness, networking capability and, in measurement technology, by their high image quality. In contrast to conventional cameras, they usually have no control elements such as buttons, switches or the like.

With the setting options of the cameras, such as the exposure time, the image recordings can be optimized. For example, the brightness of the recorded images can be adjusted.

In principle, the camera arrangement can be designed differently and have various shapes and geometric dimensions. According to a preferred development of the invention, however, it is provided that the camera arrangement comprises a two-dimensional camera matrix in which the cameras are arranged in a common plane and preferably at a regular distance from one another.

The design of the camera arrangement in the form of a camera matrix, which can also consist of several separate camera matrices, makes it possible for the two-dimensional camera matrix, according to a preferred embodiment of the invention, to have the dimensions of the detection area of the radiation receiver, i.e. for the matrix to have the same height and width as the detection area. This can ensure that the camera matrix completely covers the detection area and can thus fully detect the radiation reflected onto the detection area.

According to a preferred development of the invention, the movement device has at least one guide rail, which is arranged vertically and/or horizontally and/or diagonally on the radiation receiver and/or to the side of the reception area and is designed to move the camera arrangement into and out of the reception area .

To move the camera array into the reception area and back out means in this case that the camera array is in a vertical plane or at a inclined arranged radiation receiver is displaced approximately perpendicularly or correspondingly inclined to the ground, so that it is completely and / or partially in the reception area, preferably in a plane parallel thereto. In particular, the guide rail can extend over the entire height of the radiation receiver. With the guide rail, the camera arrangement attached to the movement device can be moved up or down on the radiation receiver in the vertical direction. Alternatively, however, the camera arrangement can also be located within the reception area in the rest position, specifically in such a way that its lenses cannot detect any radiation from the objects. They are then moved by the guide rail in such a way that their lenses are aimed at the objects in the recording situation and can capture radiation originating from there. In this context, it is also possible that only some of the cameras are moved out of the reception area, while the other part of the cameras remains in the reception area.

A diagonal arrangement means that the guide rail is arranged on the radiation receiver in an area between vertical and horizontal in such a way that it runs from one corner of a preferably square reception area to the corner opposite this corner.

According to a preferred development of the invention, the movement device has at least one pivoting device, which is arranged to the side, above and/or below the reception area and/or in an area between the side and above or below and is designed to rotate the lenses of the camera arrangement in pan the reception area in and out again. Pivoting the camera assembly into and out of the reception area means, for example, that the camera assembly is arranged laterally next to the reception area and is preferably pivoted into a plane perpendicular to the surface of the reception area, so that it is completely and/or partially in the reception area. Alternatively, however, the camera arrangement can also be located within the reception area in the rest position, specifically in such a way that its lenses cannot detect any radiation from the objects. The pivoting movement then moves them in such a way that their lenses are aimed at the objects in the recording situation and can capture radiation originating from there. In this context, too, it is possible that only some of the cameras from the Reception area is brought out while the other part of the cameras remains in the reception area.

In principle, the pivoting movement can also be a folding movement, so that the pivoting device can also be a device that can be opened and folded in and is designed to move the camera arrangement into and out of the recording situation.

According to a preferred embodiment of the invention, the movement device has a plurality of displacement devices, which are arranged to the side and/or above and/or below the radiation receiver and/or diagonally on the radiation receiver and are designed to move one camera of the camera arrangement or a part of the To move the camera matrix in and out of the receiving area. Each individual camera or the camera matrix is shifted linearly and in a plane parallel to the surface of the reception area. The displacement devices can be arranged, for example, along the circumference of the reception area. For example, from the right and/or left, above and/or below and/or diagonally outside the reception area of the radiation receiver, several linearly movable displacement devices, each with a camera or part of the camera matrix, can be moved into and out of the reception area of the radiation receiver, with the cameras in the pickup position at the time of an image pickup operation form a camera array. A diagonal arrangement means that the displacement device is arranged on the radiation receiver in an area between vertical and horizontal in such a way that it runs from one corner of a preferably square reception area to the corner opposite this corner. If the reception area is circular, the displacement preferably takes place radially. Alternatively, however, the camera arrangement can also be located within the reception area in the rest position, specifically in such a way that its lenses cannot detect any radiation from the objects. They are then moved by the displacement device in such a way that their lenses are directed at the objects in the recording situation and can capture radiation originating from there. It is also possible in this connection that only some of the cameras are moved out of the reception area, while the other part of the cameras remains in the reception area. In addition or as an alternative to the guide rail and/or pivoting device and/or to the displacement devices, the movement device comprises a plurality of rotation devices, which are each designed to rotate a camera of the camera arrangement or part of the camera matrix, i.e. several cameras at the same time, in order to rotate their vertical and/or or rotate horizontal axis. Alternatively, the camera arrangement can also be located within the reception area in the rest position, in such a way that its lenses cannot detect any radiation from the objects. Because the cameras are rotated, the lenses of the cameras for capturing the radiation can be rotated into or out of a light cone of the radiation that hits the receiving area, without having to be shifted in height or swiveled sideways. In particular, a combination of a rotation device with the guide rail and/or a pivoting device is also possible. In addition, not all cameras have to be moved out of the reception area for the quiet situation.

According to a preferred development of the invention, a filter system is connected in front of each of the cameras to reduce the wavelength range of the radiation reaching the cameras and to weaken their radiation intensity. The filter system can be used to ensure that radiation with very high intensities can also be captured by the cameras by prior attenuation of the radiation intensity without damaging the cameras. Furthermore, the filter system makes it possible to record only a predetermined or reduced wavelength range of the radiation impinging on the cameras.

Furthermore, the filter system preferably comprises a first filter and a second filter, the filter areas of the first and second filters being selected in relation to one another such that only a small radiation area can be transmitted. The two filters and their spectral properties are superimposed in such a way that only a small spectral range visible to the cameras is allowed through to the camera sensors and can be captured by the cameras. In particular, the first filter is a narrow-band reflection filter and the second filter is an infrared reflection filter. The first filter is preferably a reflection filter that reflects radiation in the range between UV radiation and infrared radiation, preferably between 200 nm and 1200 nm, and only allows a small wavelength range, preferably 780±10 nm, to be transmitted through the filter. This narrow-band reflection filter reflects back the largest part of the radiation, mainly from the visible, but also partly from the infrared spectral range.

The second filter is preferably a reflection filter which reflects part of the radiation, the reflected radiation having a wavelength in the range of preferably 700 nm to 5000 nm. It is provided that the second filter still has a low level of transparency for radiation in the range around 780±10 nm, so that light or photons in this wavelength range can pass through the filter in the direction of the image sensor of the camera. This means that in the range around 780 ± 10 nm, a small proportion of the radiation is still transmitted, so that the radiation transmitted by the first filter is further weakened, but not completely blocked. In addition, the second filter preferably reflects the infrared radiation up to 2500 nm and beyond almost completely. Further combinations of different filter types are possible, including, for example, the use of an absorption filter for the long-wave spectral range. A reflection or absorption filter for the long-wave spectral range (approx. 1200 to 3000 nm) is helpful if the narrow-band spectral filter placed in front of it lets through too much radiation energy in the long-wave spectral range (e.g. at >1200 nm). The given filter transmission wavelengths are examples and can also vary depending on the filter combination. The first filter and the second filter can also be combined in a single filter, provided that this has the combined properties of the first and second filter, i.e. radiation between approx. 200 nm and at least 2500 nm is almost completely reflected and only radiation in a small wavelength range. can be transmitted through the filter. In this case, “almost completely” means that a proportion of as much as possible more than 90% of the radiation, preferably as much as possible as much as 95% of the radiation, very particularly preferably as much as possible as more than 98% of the radiation, is reflected. "Around a small wavelength range" means that only radiation with a wavelength band with a width of the order of <30 nm, preferably <20 nm, very particularly preferably <10 nm can be transmitted. According to a preferred development of the invention, the filter system includes a third filter, which is a neutral density filter. The neutral density filter further weakens the radiation so that the cameras and their image sensors are not exposed to too much radiation. For this purpose, the neutral density filter reduces the radiation energy over the entire spectral range or at least over the spectral range that is transmitted by the filters in front of it, so that the radiation for the camera sensors is sufficiently weakened. Due to the filter system, the special camera technology can therefore be exposed to highly concentrated radiation and the radiating object can be photographed with high resolution. Instead of a neutral density filter, another filter with similar reflective properties can be used.

According to a preferred development of the invention, the cameras each have a protective device with a first part that is transparent to radiation and a second part that is opaque to radiation, the diameter of the first part and the diameter of the first filter being the same or only slightly larger and/or the first part of the Protective device comprises a disc, preferably made of ceramic, borosilicate, quartz glass and / or sapphire glass. "Equal" or "slightly larger" means that the diameter of the first part and the diameter of the first filter are the same within a predetermined tolerance range. The tolerance range is preferably <25% of the diameter of the first filter.

The protective device is arranged in front of the filters, is preferably scratch-resistant, transparent and resistant to high temperatures. It is easy to clean without damaging the filters. Furthermore, the protective device can have an air slot which is designed to blow an air film into the protective device, so that contamination by dust particles, insects or the like can be avoided or reduced.

According to a preferred development of the invention, it is provided that the objects each include a heliostat and the radiation receiver includes a solar tower. The arrangement can thus include a heliostat field, ie a large number of heliostats, for example. However, the objects can also be emitters, for example a near-infrared emitter, an artificial sun or also mirror systems tracking the sun such as dish collectors, parabolic trough collectors, CPC collectors, small mirror systems or Fresnel collectors.

Finally, a preferred embodiment of the invention lies in the fact that diaphragms are arranged on the movement device, which can be moved by means of the movement device in such a way that in the rest situation they cover the lenses of the cameras in such a way that the lenses cannot detect any radiation originating from the objects. and release the lenses of the cameras in the recording situation, so that radiation originating from the objects can be recorded with the lenses. In principle, this refinement can also be combined with movable cameras. It is very preferred, however, that in this configuration the cameras are mounted in a fixed manner, that is to say they cannot be displaced, pivoted, or rotated.

According to the invention, a method for operating the device described above with the following method steps is also provided:

51) moving the camera assembly from the still situation to the recording situation,

52) synchronous recording of a respective image of the entire object field with a plurality of cameras and

53) Move the camera assembly from the capture situation to the rest situation.

Due to these method steps, it can be ensured that the camera arrangement is only moved into the recording situation, i.e. into the detection area, for the short period of one or more image recordings and is then immediately moved back into the rest position, i.e. out of the detection area. Due to the fact that the stationary situation is outside the detection area, the camera arrangement cannot cover the detection area in the stationary situation and thus cast a shadow on the detection area, which would lead to reduced solar energy absorption there.

According to a preferred development of the invention, the method includes the additional method step: S4) Alignment of at least one object based on at least one image recorded in the recording situation.

An object can be aligned based on the captured image. In this case, step S4) can take place after step S3) or even when the camera arrangement is still in the recording situation. To align the object, the target position can be compared with the actual position of the object and, if the object is misaligned, its alignment can be corrected in accordance with the target position.

In the case of a large number of cameras, all cameras preferably record at least one image of the entire heliostat field synchronously in time. The image recordings between at least 2 cameras are preferably interpolated. A heliostat may reflect the radiation onto more than one camera, and each camera captures the entire heliostat field. The cameras are then moved back from the radiation focus to their rest position.

Preferably, it is provided that the cameras not only take one picture each during the measurement process, but rather take several pictures in succession at short intervals, and thus, for example, 10 pictures per second, so that an average value can be formed and the influence of wind in the heliostat field, the can cause wobbling of the heliostats can be reduced. Thus, the possibility of incorrect measurement or incorrect alignment of heliostats can be reduced.

If the term "moving the camera arrangement" is used, this means in particular shifting of the camera arrangement along the guide rail, shifting of the cameras along the shifting devices, pivoting and/or rotating. In particular, the movements can also be combined so that, for example, the camera arrangement can be moved into the reception area of the radiation receiver and each camera can be rotated about its own axis for image recording, so that the recording area of the cameras points in the direction of the heliostat field. After the image acquisition, the cameras can be rotated again so that the acquisition area no longer points in the direction of the heliostat field. This has the advantage that the sensitive sensors of the cameras can be rotated, shifted and/or swiveled after the image has been taken from the radiation area.

For example, a cable pull can be used as the drive technology, with the cables being sufficiently far away from the focus of the beam.

The camera assembly can preferably be lowered to the ground for maintenance purposes and/or to a safety position. The measuring system can be moved along a guide rail, for example.

According to a preferred development of the invention, it is also possible to temporarily pivot a camera matrix, installed on the left and/or right side and/or above and/or below the receiver in a pivoting device, into the recording situation for the measurement process. There the cameras remain briefly in the position, all cameras take at least one synchronized image recording of the object field and are then brought back from the radiation focus to the rest position.

According to a preferred development of the invention, the method includes the additional method step:

S5) repeating steps S1) to S4) at a regular time rhythm.

In order to check the heliostat field as often as possible, this process is preferably repeated at defined intervals, for example every 1-120 seconds. If required, this process can take place in regular or irregular time rhythms at any point in time.

Furthermore, the arrangement for detecting radiation and the method for operating this arrangement for detecting radiation open up a number of further evaluation options, in particular a number of evaluation options in a solar tower heliostat field:

Firstly, the alignment, ie the direction calibration or calibration of the orientation or calibration of the alignment, of all objects is made possible. This is what happens Alignment by comparing a target position of the object's alignment with an actual position. The target position is the position in which the object reflects and/or emits the radiation in such a way that the position of the focal spot on the detection range of the radiation receiver corresponds to the target specification. With a 360° object field, the objects are aligned in such a way that there is one focal point in each direction on the 360° detection area, which the respective objects head for. The target position can be selected, for example, in such a way that the light intensity of the radiation that impinges on the detection area of the radiation receiver is at a maximum. The actual position is measured and adjusted to the target position. The associated image recordings are interpolated between at least two cameras in each case in order to be able to determine the exact mean alignment of the object.

Second, the determination of a radiation flux density distribution on the detection area of the radiation receiver is made possible. From images recorded by at least two cameras, strongly distorted images of the sun of individual objects can also be recognized on the receiver and used to calculate a very precise radiation flux density distribution. In addition to orientation detection, the arrangement also enables solar focus radiation characterization.

Thirdly, the calculation of a ripple of the mirror facets is made possible. The nature of the mirror surface, in particular the waviness of the mirror surface, can be determined using the image recordings. By recognizing the waviness of the mirror surfaces, the focal spot shape can be calculated and used to adapt target point strategies during the operation of a solar tower in order to optimize the flux density distribution.

Fourth, the determination of the coarse orientation of all objects in the object field is made possible. The rough alignment is determined by edge detection and/or detection of the corners and/or other markings of the objects to detect objects that are grossly incorrectly oriented. Objects can also be recognized which do not directly illuminate any camera of the camera arrangement. This would be the case in the event of a gross misalignment or failure of the object, in which the reflected and/or emitted by the object Radiation completely misses the reception area. A method for detecting mirror edges can be used to determine the rough alignment of the object. With a sufficiently high image resolution of the cameras, the alignment of the objects can also be resolved more finely by means of corner detection, so that the objects can be calibrated with regard to their alignment using the camera arrangement if the camera arrangement is outside the detection range of the radiation receiver. The orientation of the objects can also be measured by evaluating image recordings from a number of cameras, for example using a stereo method or averaging a number of image recordings from one or more cameras.

Fifth, as a maintenance measure, it is determined whether the adjustment of mirror facets of the objects is necessary, since misalignments of individual mirror facets can be detected. In this case, the adjustment is carried out by comparing a target position of the alignment of the object with an actual position. The target position is the position in which the object reflects and/or emits the radiation in such a way that the position of the focal spot on the detection range of the radiation receiver corresponds to the target specification. The actual position is measured and adjusted to the target position. The associated image recordings are interpolated between at least two cameras in each case in order to be able to determine the exact mean alignment of the object.

Various disruptive factors can also be identified. This includes in particular the detection of cloud passages for each individual mirror facet of each object, the detection of dirt on the mirror facets of the objects and/or the detection of heliostats with broken or otherwise defective mirror facets.

It is preferably provided that with small detection areas of the radiation receiver (e.g. single or multi-chamber radiation receiver), for example with a diameter of approx. 1 m, at least 1 camera from the left and/or right side, above and/or below or in any combination , temporarily moved or swiveled into the detection area.

Furthermore, it is possible that the camera assembly are specially protected with an additional protective device in the rest situation, the protective device before the Camera arrangement is performed when no image recording takes place and only in the recording situation for an image recording releases the camera arrangement.

The invention is explained in more detail below using a preferred exemplary embodiment with reference to the drawings.

Show in the drawings

1 schematically shows an arrangement for detecting radiation according to a preferred embodiment of the invention,

Fig. 2 shows schematically a radiation receiver according to a preferred

Embodiment of the invention in a front view,

3 schematically shows a radiation receiver according to a second preferred embodiment of the invention in a side view,

4 schematically shows a radiation receiver according to a third preferred embodiment of the invention in a perspective view,

5 schematically shows a radiation receiver according to a fourth preferred exemplary embodiment of the invention in a front view,

6 schematically shows a camera matrix according to a preferred embodiment of the invention,

7 schematically shows a camera according to a preferred embodiment of the invention,

8 schematically shows a method for operating the arrangement according to a preferred embodiment of the invention, Fig. 9 shows a schematic section of excerpts from the receiving area of a

Radiation receiver according to a preferred embodiment of the invention,

Fig. 10 schematically shows a plan view of an arrangement of a plurality of

Radiation receiving devices according to a further preferred exemplary embodiment of the invention, as well as sections of the receiving area of this radiation receiver and schematically in section

Fig. 11 schematically in section excerpts from the receiving area of a

Radiation receiver according to yet another preferred embodiment of the invention.

An arrangement 1 for detecting radiation 4 is shown schematically in FIG. A radiation source, in this case the sun 7, emits radiation 4, indicated here by solid lines. The radiation 4 is reflected by objects 6, in this case heliostats, onto a detection area 3 of a radiation receiver 2, indicated here with dashed lines. Several objects 6 are in a common object field 5. Each individual object 6 is aligned in such a way that it reflects the radiation 4 onto the detection area 3 as effectively as possible. 1 thus shows a classic structure of a solar tower power plant.

As already mentioned, the radiation receiver 2 includes a movement device to which a camera arrangement 8 is attached. The movement device can be designed in different ways, as shown below by way of example for a selection of movement devices.

2 schematically shows a radiation receiver 2 with a guide rail 11 in a front view. The camera arrangement 8 can be displaced in the vertical direction on the guide rail 11 . Position (a) shows the camera arrangement 8 when it is at rest. The camera arrangement 9 is located outside the detection area 3 of the radiation receiver 2. In order to be able to take a picture, the camera arrangement 8 is placed in the detection area 3 of the radiation receiver 2, i.e. in its recording situation hazards. This position is shown in (b). In order to be able to service the individual cameras 9 of the camera arrangement, there is a further position (c) in which the camera arrangement 8 can be lowered down to the ground so that cleaning and/or repair work can be carried out. The radiation receiver 2 is shown vertical in FIG. 2, but it can also be inclined. An embodiment with a horizontally arranged guide rail and with a horizontal displacement of one or more camera matrices is also possible. Then cleaning and/or repair work must be carried out at the level of the radiation receiver 2 .

3 schematically shows a radiation receiver 2, which has a rotation device 13 as a movement device, in a side view. The rotation device 13 is connected to the camera arrangement 8 and can rotate this camera arrangement out of the radiation in the rest situation (a), so that the viewing direction of the cameras 9 is oriented to the side or to the rear and not into the radiation 4 reflected by the objects 6 . In order to record an image, the camera arrangement 8 is rotated into the recording situation (b) so that the cameras 9 “look” directly into the radiation 4 . 3 shows that the camera arrangement 9 is not moved vertically between the rest situation (a) and the recording situation (b). A combination of the guide rail 11 shown in Fig. 2 and/or the pivoting device shown in Fig. 4 and/or the linearly movable device shown in Fig. 5 and/or a device that can be opened and folded in and the rotating device 13 is possible, but in 2 and 3 not shown.

4 schematically shows a radiation receiver 2 which has a pivoting device 12 as a movement device. With the pivoting device 12, the camera arrangement 9 can be pivoted into the detection area 3 of the radiation receiver 2, so that the camera arrangement 9 is located outside and to the side of the detection area 3 in the rest situation (a) and in front of the detection area 3 in the recording situation (b). The pivoting device 12 is designed in such a way that the pivoting movement corresponds to a “folding away” of the camera arrangement.

5 schematically shows a radiation receiver 2 which has a plurality of displacement devices 16 as a movement device. The displacement devices 16 are upper and arranged below the detection area 3 . The cameras 9 of the camera arrangement 8 are located outside of the detection area 3 in the rest situation (a) and in the detection area 3 in the recording situation (b).

Furthermore, it is possible to combine the movement devices shown, i.e. the guide rail 11, the swiveling device 12 and/or the rotating device 13, so that the movement of the camera arrangement 9 between the stationary situation and the recording situation comprises a combination of shifting, swiveling and/or rotating.

As already mentioned, the cameras 9 of the camera arrangement 8 can be arranged in a camera matrix 10 . This is shown in FIG. The cameras 9 are arranged in a common plane and at a regular distance from one another. The cameras 9, as shown in FIG. 6, can be arranged in vertical rows. A horizontal arrangement, as indicated in FIG. 4, is also possible.

A single camera 9 of the camera arrangement 8 is shown schematically in FIG. A filter system 14 is connected upstream of the camera 9 . The filter system 14 consists of a first filter 14a, a second filter 14b and a third filter 14c. Depending on the desired function, the filter types can have different properties and can be combined with one another as desired. Here it is provided that the first filter 14a is a narrow-band reflection filter and the second filter 14b is an infrared reflection filter. The third filter 14c is a neutral density filter, which further attenuates radiation 4 so that the cameras 9 are not exposed to too much radiation even in the case of high-intensity radiation 4 . A single filter can also be used instead of the first and second filters, provided that it has the combined properties of the first and second filters.

A protective device 15 is connected upstream of the filter system 14 . The protective device 15 has a first radiation-transmissive part 15a and a second radiation-opaque part 15b. The diameter of the radiation-transmissive part 15a is preferably equal to the diameter of the first filter 14a or otherwise as slightly larger as possible, so that the camera 9 can be used in areas in which no radiation 4 hits the camera 9 should meet, so outside the camera lens and the filter system 14 is protected. The radiation-transmissive part 15a comprises a disc made of ceramic, borosilicate, quartz glass and/or sapphire glass, for example, so that the protective device 15 is scratch-resistant, transparent and resistant to high temperatures and can be easily cleaned without damaging the filter system 15.

A method for operating the arrangement 1 is shown schematically in FIG. In a first step S1, the camera arrangement 9 is moved from the rest position to the recording situation. The camera arrangement 9 is then located in the detection area 3 of the radiation receiver 2. In a second step S2, the cameras 9 record an image of the entire object field 5 synchronously in time. This means that each camera 9 of the camera arrangement 8 captures the object field 5 completely and all the cameras 9 take an image at the same time. In a next step S3, the camera arrangement 9 is moved back into the rest position, so that the camera arrangement 9 is then located outside the detection area 3. Then, in a next step S4, at least one object is aligned using the image recording, so that the new position of the object results in radiation 4 being optimally reflected onto detection area 3. However, the objects 6 can also be positioned when the camera arrangement 9 is still in the recording situation. However, this is not shown in FIG. A further step S5 provides that steps S1 to S4 are repeated at a regular time rhythm. This can be done every 1s to 120s, for example. If required, this process can take place in regular or irregular time rhythms at any point in time. Due to external influences, such as wind, it can happen that the objects 6 are moved unintentionally during the image recording process. It is therefore preferably provided that each camera of the camera arrangement carries out a plurality of image recordings during the image recording process. Regular checking of the positioning of the objects 6 (S1 to S4) can ensure that the objects 6 are optimally aligned as often as possible.

In the exemplary embodiments of the invention described below and shown in FIGS. 9 to 11, the radiation receiver 2 is constructed in such a way that it has a plurality of radiation receiving devices 17 which are at least partially spaced apart and/or have cutouts. In this way the receiving area 3 of the radiation receiver 2 also includes areas in which no radiation is received by the radiation receiver 2 . In the present case, these areas are used to position the cameras 9 .

9 shows a schematic section of a detail from the reception area 3 of a radiation receiver 2 which has a multiplicity of radiation reception devices 17, of which two radiation reception devices 17 adjacent to one another are shown here as an example. These are arranged at a distance from one another, so that a camera 9 can be arranged in the area between them. In the present case, the arrangement of the camera 9 is such that the camera 9 can be rotated so that, as shown in FIG. 8a, its lens rotates into the radiation 4 and, as shown in FIG. 8b, its lens also rotates out again the radiation 4 can be rotated out. In this way, it is possible to switch between the recording situation and the resting situation.

An alternative embodiment is shown in FIG. 10. There, FIG. 10a shows a top view of an arrangement of a plurality of radiation receiving devices 17, each of which has an omission of a radiation receiving device 17 at different locations, so that a camera 9 can be positioned there . Instead of rotating these cameras 9 back and forth into the radiation 4, it is provided here to move the cameras 9 behind a stationary aperture 18, as shown in FIGS to remove the cameras 9 from the radiation 4, or to move from the area behind the stationary aperture 18 into the radiation 4 in order to come into the recording situation. Instead of such a movement of the cameras 9, it is also possible, as shown in FIG. List of reference symbols arrangement radiation receiver reception area radiation object field object sun camera arrangement camera camera matrix guide rail pivoting device rotation device filter system a first filter b second filter c third filter protective device a first radiation-transmissive part b second radiation-opaque part displacement device radiation receiving devices stationary apertures movable apertures

Claims

23 patent claims

1. Arrangement (1) for detecting radiation, with a radiation receiver (2) with a reception area (3) for receiving radiation (4), a plurality of objects (6) arranged within an object field (5) for reflecting and/or Emitting radiation (4) onto the reception area (3) of the radiation receiver (2), a camera arrangement (8) having a plurality of cameras (9), the cameras (9) each being provided with a lens for detecting the radiation, and a movement device, wherein the movement device is designed to move the camera arrangement (8) from a rest position to a recording situation and from the recording situation back to the rest position, the cameras (9) are arranged in the rest position in such a way that their lenses are located outside of the reception area (3), so that no radiation originating from the objects can be detected with the cameras (9), the cameras (9) are arranged in such a way in the recording situation et are that their lenses are located within the reception area (3), so that the cameras (9) can detect radiation originating from the objects, and the cameras (9) are designed and set up in such a way that they can be used in the recording situation to entire object field (5) can be detected.

2. Arrangement (1) according to claim 1, wherein the camera arrangement (8) comprises a camera matrix (10) in which the cameras (9) are arranged in a common plane and preferably at a regular distance from one another.

3. Arrangement (1) according to one of the preceding claims, wherein the movement device has at least one guide rail (11) which is arranged vertically and/or horizontally and/or diagonally on the radiation receiver (2) and/or to the side of the receiving area (3). and is designed to move the camera assembly (8) into and out of the reception area (3).

4. Arrangement (1) according to one of the preceding claims, wherein the movement device has a plurality of displacement devices (16) which are arranged laterally and/or above and/or below the radiation receiver (2) and/or diagonally on the radiation receiver (2). and are designed to move one camera (9) of the camera arrangement (8) into and out of the reception area (3).

5. Arrangement (1) according to one of the preceding claims, wherein the movement device has at least one pivoting device (12) which is arranged to the side and/or above and/or below the reception area (3) and is designed to rotate the lenses of the camera arrangement ( 8) to swing in and out of the reception area (3).

6. Arrangement (1) according to any one of the preceding claims, wherein the movement device comprises a plurality of rotation devices (13), which are each designed to rotate a camera (9) of the camera arrangement (8) or a part of the camera matrix (9) around their rotate vertical and/or horizontal axis.

7. Arrangement (1) according to one of the preceding claims, wherein the cameras (9) to reduce the wavelength range of the cameras (9) reaching radiation (4) and to weaken the radiation intensity is connected upstream of a respective filter system (14).

8. Arrangement (1) according to any one of the preceding claims, wherein the filter system (14) has a first filter (14a) and a second filter (14b), wherein the filter areas of the first filter (14a) and the second filter (14b) so are chosen to each other so that only a small wavelength range can be transmitted.

9. Arrangement (1) according to any one of the preceding claims, wherein the filter system (14) has a third filter (14c) and the third filter (14c) is a neutral density filter.

10. Arrangement (1) according to one of the preceding claims, wherein the cameras (9) each have a protective device (15) with a first radiation-transmissive part (15a) and a second radiation-opaque part (15b), the diameter of the first part (15a ) and the diameter of the first filter (14a) is the same, and/or wherein the first part (15a) of the protective device (15) comprises a disc, preferably made of ceramic, borosilicate, quartz glass and/or sapphire glass.

11. Arrangement (1) according to any one of the preceding claims, wherein the objects (6) each comprise a heliostat and the radiation receiver (2) comprises a solar tower.

12. Arrangement (1) according to one of the preceding claims, wherein shutters are arranged on the movement device, which can be moved by means of the movement device in such a way that in the rest position they cover the lenses of the cameras (9) in such a way that the lenses do not Objects (6) originating radiation can be detected, and release the lenses of the cameras (9) in the recording situation, so that the lenses from the objects (6) originating radiation can be detected.

13. Method for operating an arrangement (1) according to claim 1 to 11, with the following method steps:

51) moving the camera arrangement (8) from the rest situation to the recording situation,

52) synchronous recording of a respective image of the entire object field (5) with a plurality of cameras (9) and

53) Moving the camera arrangement (8) from the recording situation to the resting situation.

14. The method according to claim 13, with the following additional method step:

54) aligning at least one object (6) using at least one image recorded in the recording situation.

15. The method according to claim 13 or 14, with the following further method step: 26

S5) repeating steps S1) to S4) in a regular or irregular time rhythm, preferably every 1 s to 120 s or smaller or larger time rhythms or as required.