Assembly, use of an assembly, and method for ascertaining at least one parameter

Abstract

The invention relates to an assembly (100) for ascertaining at least one parameter for determining components of a global irradiance, said assembly comprising an evaluation and control device (110) and a camera assembly (120) having at least one camera, the at least one camera being fixed at a predefined distance from an earth surface (20) at least while ascertaining the parameter, the camera assembly (120) being designed to capture camera data in a spatial field of view of approximately 360° around the camera assembly (120), the camera data being suitable for deriving information concerning solar radiation and / or the position and / or properties of clouds (12). The invention also relates to: the use of such an assembly; a method for ascertaining at least one parameter for determining at least one component of a global irradiance; and a computer programme.

Description

[0001] Description

[0002] title

[0003] Arrangement, use of an arrangement and method for determining at least one parameter

[0004] State of the art

[0005] The invention relates to an arrangement for determining at least one parameter for determining at least one component of a global irradiance, a use of an arrangement for determining at least one parameter for determining at least one component of a global irradiance and a method for determining at least one parameter for determining at least one component of a global irradiance.

[0006] Cloud cameras and shadow cameras, as well as corresponding arrangements and their application, are described in the article by Kuhn, P. et al. "Benchmarking three low-cost, low-maintenance cloud height measurement systems and ECMWF cloud heights against a ceilometer," Solar Energy, Vol. 168, 2018, pp. 140-152, DOI:

[0007] 10.1016 / j.solener.2018.02.050. This describes a multi-camera setup, in which one camera has a field of view directed toward the sky and is capable of recording sky data. A shadow camera positioned several hundred meters away can record Earth data. Cloud camera setups can be used for the automated detection of sky cloud cover and for the creation of very short-term forecasts of solar radiation, for example, for the more efficient operation of power supply systems consisting of solar arrays and diesel generators or battery storage systems.

[0008] These cloud camera-based forecasting systems typically detect clouds in the camera images. Using data from at least a second cloud camera, the height and speed of the clouds, and therefore their future position, can be determined. Based on the cloud position, a prediction can be made regarding the shading of specific areas.

[0009] Shadow camera arrays are typically installed on tall towers or ridges overlooking the monitored area. Shadow cameras can create high-resolution maps of solar radiation around the point of installation. Shadow cameras with a rather narrow field of view are used. By comparing the position of cloud shadows in images between different timestamps, these systems can determine the speed of clouds over the ground.

[0010] Monitoring systems for solar power plants or measurement systems for determining the solar resource at a planned solar power plant site are often equipped with sky-facing pyranometers and, in some cases, also with ground-facing pyranometers to measure the radiation originating from the sky and reflected from the ground, respectively. These measurements are used to evaluate the performance of a solar power plant or to assess the solar resource at the site. Furthermore, the publication "Shadow camera system for the generation of solar irradiance maps", Solar Energy, 157, 2017, pp. 157-170. DOI: 10.1016 / j.solener.2017.05.074 discloses a multi-camera arrangement, with the camera array consisting of six cameras capturing images of the ground from a tall tower.

[0011] Disclosure of the invention

[0012] The object of the invention is to provide a cost-effective arrangement for determining at least one parameter for determining at least one component of a global irradiance, wherein the measuring setup is located at one location.

[0013] A further object of the invention is to provide a use of such an arrangement for determining at least one parameter for determining at least one component of a global irradiance, which determines one or more parameters cost-effectively and / or reliably.

[0014] A further object of the invention is to provide a method for determining at least one parameter for determining at least one component of a global irradiance, which method determines the at least one parameter cost-effectively and / or reliably.

[0015] These objects are achieved by the features of the independent claims. Advantageous embodiments and advantages of the invention emerge from the further claims, the description, and the drawings. The following are definitions of terms that apply to the inventive arrangement for determining at least one parameter for determining at least one component of a global irradiance, the inventive use of the arrangement, and the inventive method for determining at least one parameter.

[0016] An evaluation and control device is defined below as a physical assembly or a logical group of interacting hardware and / or software components, or a processor. The evaluation and control device comprises at least one signal input for receiving camera data and at least one signal output for outputting measurement results and / or camera data.

[0017] At least one computing unit can evaluate the received camera data through appropriate programming and calculate the at least one parameter and / or other measurement results. In this case, multiple computing units can be provided, each of which carries out one or more method steps and / or one or more evaluation steps. Additionally or alternatively, multiple computing units can be provided for determining or determining one or more parameters. These computing units or further computing units can determine one or more components of the global irradiance. The calculations and / or determinations and / or ascertainments can be carried out centrally at one location or decentralized at different locations. At least one storage unit can store intermediate results and / or final results and / or determined values ​​of the parameters and / or at least one component of the global irradiance.The camera data can be sent to the signal input or from the signal output via a cable or wirelessly. With the arrangement according to the invention and the use of the arrangement according to the invention, one or more evaluation and control devices can be involved in the evaluation and calculation. The evaluation can additionally or alternatively be implemented at least partially on a server. The evaluation can advantageously be carried out using a corresponding computer program designed to carry out the calculation steps. Likewise, a computer program product can be provided on which a computer program designed to carry out the calculation steps is stored.

[0018] The evaluation and control device can be understood as a physical assembly. However, the evaluation and control device could also simply be implemented on a server. In this case, this assembly is a computer program and not physically present. The evaluation and control device can retrieve data from or store it in a cloud.

[0019] A camera arrangement can be understood below as a camera arrangement which comprises a camera which captures a spatial field of view of 360° or at least approximately 360° around the camera arrangement. Alternatively, the camera arrangement can comprise a plurality of cameras which together capture the spatial field of view of at least approximately 360° around the camera arrangement. The camera arrangement can have a first camera and a second camera. Advantageously, the spatial field of view of at least approximately 360° around the camera arrangement is composed of a spatial first partial field of view and a spatial second partial field of view, each of 180° or at least approximately 180° around the camera arrangement. The partial fields of view can be arranged along a common axis; in particular, the common axis can be aligned substantially in a vertical direction, or the common axis can be aligned at a tilt angle to the vertical direction.

[0020] The spatial field of view of at least approximately 360° can advantageously be a three-dimensional field of view. The spatial partial field of view of at least approximately 180° can be a three-dimensional partial field of view.

[0021] The camera arrangement may have a common axis. The common axis may extend through the camera or the multiple cameras of the camera arrangement. The common axis may be aligned substantially vertically, thus forming a substantially vertical axis, or tilted at a tilt angle relative to the vertical direction, thus forming an oblique axis.

[0022] Alternatively, each of the cameras can be arranged on a separate axis. These can be essentially parallel to each other or tilted relative to each other.

[0023] The downward-looking camera can advantageously capture the ground below the upward-looking camera. The cameras can be arranged in a common mounting arrangement or in separate mounting arrangements. The one or more axes can be aligned substantially in a vertical direction. Alternatively, the one or more axes can be aligned at a tilt angle relative to a vertical direction.

[0024] A short distance between the axes allows both cameras to be shaded by passing clouds at approximately the same time. A short distance between the axes of a few meters, especially no more than about 10 meters, is advantageous.

[0025] Furthermore, a field of view of at least approximately 360° can only be reconstructed with sufficient accuracy from the partial fields of view of the cameras if the two cameras are positioned close to each other. For this purpose, a maximum distance of approximately 10 m should not be exceeded. This prevents the cloud shadows in the image of the ground-facing camera from no longer corresponding sufficiently accurately with the clouds in the image of the sky-facing camera if the distance is too great. This effect can be particularly relevant for very low clouds at a height of just a few hundred meters.

[0026] The spatial field of view of at least approximately 360° around the camera arrangement can extend in two opposite directions and, in total, realize the spatial field of view of at least approximately 360°.

[0027] If the camera arrangement comprises a plurality of cameras, the first camera and the second camera can form the common axis, wherein the common axis can be aligned substantially in the vertical direction and form the substantially vertical axis, or can be the axis tilted at a tilt angle to the vertical axis, which can form the oblique axis. If the cameras are arranged on a common axis, the field of view of the first camera can extend upwards along the common axis, and the field of view of the second camera can extend downwards along the common axis. Alternatively, the partial fields of view can extend along a plurality of axes, in particular two axes. These axes can be substantially parallel to one another or inclined relative to one another. The one or more axes can be aligned substantially in a vertical direction.Alternatively, the one or more axes may be aligned with a tilt angle to a vertical direction.

[0028] In particular, the one or more axes may be arranged so that the downward-looking camera can capture the ground below the upward-looking camera.

[0029] The two axes are advantageously arranged close to each other. A close distance between the axes allows both cameras to always be exposed to passing clouds at approximately the same time. A short distance between the axes of a few meters, especially no more than about 10 meters, is advantageous.

[0030] Furthermore, a field of view of approximately 360° can only be reconstructed with sufficiently high accuracy from the partial fields of view of the cameras if the two cameras are arranged close to each other. For this purpose, a maximum distance of approximately 10 m should not be exceeded. This can prevent the cloud shadows in the image of the camera looking at the ground from no longer corresponding sufficiently accurately with the clouds in the image of the camera looking at the sky if the distance is too great. This effect can be particularly relevant with very low clouds at an altitude of just a few hundred meters. Thus, with two cameras arranged along the same common axis, the spatial field of view of at least approximately 360° can each be formed into a spatial partial field of view of at least approximately 180°, which forms the spatial field of view of approximately 360°.The spatial partial field of view of at least approximately 180° forms a hemispherical or at least approximately hemispherical field of view.

[0031] A spatial field of view of at least approximately 360° around the camera arrangement is understood below to mean a spherical or at least approximately spherical field of view around a center point.

[0032] In the following, hemispherical is to be understood as meaning that the enclosed shape is at least approximately hemispherical. Likewise, spherical is to be understood as meaning that the enclosed shape is at least approximately spherical.

[0033] The camera(s) can be arranged at this center point. The spatial field of view of at least approximately 360° can be divided into several segments. The center point can advantageously be located on the common axis, which can be configured as a substantially vertical axis or an oblique axis. This allows camera data from one segment to be evaluated independently of camera data from other segments.

[0034] Alternatively, the spatial field of view of at least approximately 360° can be reconstructed from partial fields of view of the two cameras of at least approximately 180°, if these are arranged on axes closely spaced from each other. Camera data can be understood below as cloud-related data caused by clouds. Additionally or alternatively, camera data can be understood below as cloud-related data caused by cloud shadows.

[0035] Additionally or alternatively, camera data may be understood below as solar radiation-related data caused by the intensities of at least one component of the global irradiance. In this case, the camera data may also be caused by the intensities of multiple components of the global irradiance.

[0036] In this case, camera data can be understood as images of the sky. Additionally or alternatively, camera data can be understood as images of regions of the sky. Additionally or alternatively, camera data can be understood as images of the Earth's surface. Additionally or alternatively, camera data can be understood as images of regions of the Earth's surface.

[0037] Additionally or alternatively, camera data can be image features of one or more color channels of an image. Such image features can consist of the texture and / or structure and / or the color or the ratio of color channels and / or brightness. These image features can be caused by clouds or other elements in the sky. Additionally or alternatively, these image features can be caused by cloud shadows and / or other elements on the ground. Image features that are not caused by clouds and / or cloud shadows can be sorted out using suitable methods and thus cannot be used for evaluation. Additionally or alternatively, camera data can be intensity values ​​of one or more color channels and / or structural image features, particularly in the image area of ​​the sun.The intensity values ​​and structural features can be caused by radiation incident on at least one lens of the respective camera and the resulting reflections and refractions and other optical and electronic effects.

[0038] The images and / or the image features and / or the intensity values ​​can be evaluated. This can include, among other things, recording a current status.

[0039] Additionally or alternatively, a change in the images and / or the image features and / or the intensity values ​​over time can also be recorded.

[0040] Determining a parameter is understood below to mean capturing and / or calculating a current value of the parameter. Additionally or alternatively, determining a parameter is understood below to mean capturing and / or calculating a predicted future value of the parameter. The predicted future value of the parameter can be determined, for example, based on current and / or past camera data.

[0041] In the following, a parameter is understood to be a quantity determined using or from the camera data. This quantity can be a cloud shadow position and / or a cloud feature position and / or a cloud speed and / or a cloud height. Additionally or alternatively, this quantity can be a future cloud shadow position and / or a future cloud feature position and / or a future cloud speed and / or a future cloud height. Additionally or alternatively, this quantity can also be a component of the global irradiance and / or a combination of several components of the global irradiance or the global irradiance. The recorded or determined values ​​for the component of the global irradiance and / or for the combination of several components of the global irradiance and / or for the global irradiance can be further refined.

[0042] Determining the at least one component of the global irradiance can be understood below as detecting and / or calculating a current value of the at least one component of the global irradiance. Additionally or alternatively, determining the at least one component of the global irradiance can be understood as calculating a future value of the at least one component of the global irradiance.

[0043] In the following, the at least one component of the global irradiance can be understood as a quantity determined with or from the camera data and / or a quantity determined with or from the parameters.

[0044] A component of global irradiance can be one of the following solar radiations or a combination of the following: direct radiation, diffuse radiation, and radiation reflected from the Earth's surface. All of these together constitute the global irradiance.

[0045] A system for determining at least one parameter for determining at least one component of a global irradiance is proposed, comprising an evaluation and control device and a camera system. The at least one camera is fixed at a predetermined distance from the Earth's surface, at least for determining the at least one parameter. The camera system is configured to capture camera data in a spatial field of view of at least approximately 360° around the camera system.

[0046] Conveniently, a mounting arrangement can fix at least one camera. If two or more cameras are used, the cameras can be fixed by the same mounting arrangement. Optionally, cameras can also be fixed in different mounting arrangements.

[0047] Advantageously, the spatial field of view of at least approximately 360° around the camera arrangement is composed of a spatial first partial field of view and a spatial second partial field of view of at least approximately 180° around the camera arrangement, which are arranged along a common axis or, if two cameras are used, on two files spaced apart at a short distance from one another, in particular wherein the common axis or the plurality of axes are aligned substantially in a vertical direction, or wherein the common axis or the plurality of axes are aligned at a tilt angle to the vertical direction.

[0048] The at least one camera of the camera arrangement can be arranged on the at least one axis that forms the vertical axis or the oblique axis, wherein the spatial field of view can extend upwards and downwards by at least approximately 360° along the vertical axis(es) or the oblique axis(es). In this case, an upper spatial partial field of view of at least approximately 180° and a lower spatial partial field of view of at least approximately 180° can be formed, which have the common substantially vertical axis or oblique axis, in particular a substantially vertical central axis or oblique central axis, or are correspondingly spaced from one another on different axes. The upper partial field of view and the lower partial field of view can each form an upper hemisphere and a lower hemisphere.

[0049] The upper hemisphere and the lower hemisphere, with their straight rear surfaces, i.e., their rear sides, can form a common horizontal surface, in particular a circular surface, running perpendicular to the essentially vertical or oblique axis. The center of the camera arrangement can be located at the intersection point of the common axis and the horizontal axis.

[0050] The at least one camera can be an RGB camera or an infrared camera. The at least one camera can, for example, capture 24 images per second. These images can be assigned a corresponding time stamp. Other image generation rates can also be selected. Additionally, extended setups with, for example, shading devices are conceivable to reduce the interference of direct sunlight.

[0051] The camera arrangement can in particular be designed to capture camera data in a field of view of at least approximately 360° around the camera arrangement, wherein the camera data is suitable for deriving information on solar radiation and / or on the position and / or properties of clouds. The holding arrangement can fix the camera at a specific distance above the ground to determine the at least one parameter. In this case, the holding arrangement can be a locally fixed arrangement, for example a suitable rod or scaffold. Additionally or alternatively, the holding arrangement can be a movable arrangement, for example a drone which can be used mobile and which fixes at least one camera at a specified height at a specified location.

[0052] The holding arrangement can be designed such that the camera arrangement is arranged on the common axis and a spatial field of view of at least approximately 360° is formed.

[0053] The evaluation results of the camera data, for example, from individual color channels, can be compared with the evaluation results of other color channels. Additionally or alternatively, evaluation results with different timestamps of a color channel can be compared with each other. Further evaluation of the evaluation results with evaluation results with different timestamps or with evaluation results from a different color channel is also possible.

[0054] In an embodiment in which the field of view of at least approximately 360° is composed of two partial fields of view of at least approximately 180° at a given location, evaluation results of a first partial field of view of at least approximately 180° and evaluation results of a second partial field of view of at least approximately 180° can advantageously be combined. This advantageously eliminates the need to rely on estimated values ​​or values ​​from external data sources to determine most of the parameters for determining at least one component of a global irradiance, making the determination of the parameters for a given location more accurate and reliable than with conventional arrangements that rely on estimated values ​​and values ​​from external data sources. Furthermore, no additional sensor units are required.

[0055] Typically, the irradiance of at least one component of the global irradiance is specified with respect to a surface upon which it impinges. This surface may be inclined relative to the Earth's surface and, for example, may also face the Earth's surface.

[0056] This allows the current direct radiation, the current diffuse radiation, the current radiation reflected from the Earth's surface, and the current global irradiance to be determined from the parameters and / or directly from the camera data. This makes it possible to advantageously estimate the current performance of a solar system.

[0057] Furthermore, by determining a future value for solar radiation, a prediction for future diffuse radiation, future radiation reflected from the Earth's surface, and future global irradiance can be derived from the parameters. This can be used to advantageously estimate the future performance of a solar system.

[0058] Furthermore, in addition to the determined parameters for predicting future solar radiation, current solar radiation values ​​can also be used. The field of view of at least approximately 360° around the camera array advantageously combines the advantages of a setup with a sky camera oriented toward the sky, also known as a cloud camera, with the advantages of a setup with a ground camera oriented toward the ground, also known as a shadow camera, thus compensating for the disadvantages of both the sky camera and the cloud camera.

[0059] To achieve these advantages, the camera data captured in a field of view of at least approximately 360° can be evaluated. Advantageously, the camera data can be simultaneously captured at a common location, for example, with cameras on a common axis or on axes closely spaced from each other, and evaluated for this location.

[0060] By combining these advantages, a camera array with a field of view of at least approximately 360° can be sufficient to capture enough camera data to reliably measure and / or predict desired parameters. This eliminates the need for additional cameras at other locations or additional sensor units.

[0061] This allows a large section of the sky to be captured and monitored; clouds in particular can be detected long before their shadows arrive in the monitored area, and corresponding forecasts can be made.

[0062] A further advantage of analyzing camera data captured within a field of view of at least approximately 360° around the camera array is that certain parameters, such as cloud speed above the ground, can be precisely and directly derived from this data. The monitored and captured section of the ground depends, among other things, on the height at which the at least one camera, which is directed toward the ground, is located.

[0063] To ensure reliable forecasting, ground cameras are typically mounted on high towers or ridges to enlarge the area of ​​the ground they monitor. Due to the height, clouds floating between the camera and the ground can prevent or complicate ground monitoring in these setups.

[0064] Advantageously, a prediction can be determined using camera data from at least one camera directed towards the sky, whereby a large section of the ground is not necessarily required to monitor the ground, so that the camera arrangement can be arranged at a lower height above the ground, in contrast to known shadow camera arrangements.

[0065] For example, the mounting arrangement can fix the at least one camera at a distance of 1-100 m from the ground, which is typical for albedo measurements. The minimum distance of the at least one camera from the ground can depend on the ground. At locations with snow, unmown grass, or crop plants on the ground, a height of 10 m, for example, should be selected to avoid interference from uneven surface areas. Lower heights are also possible for surfaces with less vegetation and / or in areas with little snowfall. Furthermore, the minimum height can be selected so that gradients of the intensity of the RGB channels of the at least one camera aligned with the ground can be reliably identified, so that the parameters derivable from them can be determined reliably and precisely.

[0066] A maximum distance of at least one camera aligned to the ground prevents low-lying clouds from hindering the acquisition of camera data. This maximum distance must be determined depending on the intended use and location. For example, if clouds at an altitude of 500 m or more above the camera are of interest, the at least one camera should be mounted at a height of no more than 100 m to reliably capture these clouds. If the arrangement is also used to measure the radiation reflected from the ground, a shorter distance is advantageous.

[0067] As distance increases, the area included in the measurement of radiation reflected from the ground also increases. This area can potentially be affected by unwanted influences such as trees, reflective objects, land use, etc.

[0068] Because the camera array is fixed at a maximum height of 100 m, the costs for the mounting system can be reduced. Furthermore, such a fixed camera array can be set up quickly and easily anywhere, allowing for flexible deployment.

[0069] Alternatively, a drone can simply fly at such an altitude and can also be deployed flexibly at multiple locations. This also allows the mounting arrangement to be relocated once the desired parameters have been calculated. This makes it easy and cost-effective to assess the suitability of a site, for example, for a solar farm.

[0070] Furthermore, the camera array can be mounted on the upper edge of a building. In this case, the building could be a surveillance building, a distribution center for a solar power plant, or a residential building. No tower or other tall building is required. If the camera array's field of view is restricted by the building, capturing camera data and determining at least one parameter can be difficult.

[0071] Advantageously, the camera data can be acquired at a common location using the arrangement according to the invention. This eliminates the need to transfer camera data between two locations and convert the data from one location to the other. This can facilitate maintenance and operation of the arrangement according to the invention.

[0072] In particular, a reduced number of cameras or a reduced number of camera arrangements can reduce the effort required for hardware and thus the costs for the hardware.

[0073] According to a favorable embodiment of the arrangement, the field of view of at least approximately 360° around the camera arrangement at a predetermined location can be composed of a first partial field of view and a second partial field of view, each of at least approximately 180° around the camera arrangement. At least one first camera records camera data in the first partial field of view and at least one second camera records camera data in the second partial field of view, wherein the two partial fields of view of the cameras complement each other to form a field of view of at least approximately 360°. The cameras are each designed, in particular, as fisheye cameras. The orientation of the fields of view can be chosen as desired. For example, it is possible for the fields of view to be aligned laterally, so that one camera records a section of the ground and a section of the sky on one side and the other camera records a section of the ground and a section of the sky on an opposite side.The arrangement and orientation of the cameras can be freely selected, as long as a total field of view of at least approximately 360° around the camera arrangement is captured. The arrangement of the cameras can be aligned along a single common axis or along closely spaced axes, whereby the one or more axes can be aligned substantially vertically and form a substantially vertical axis, or tilted at a tilt angle to the vertical axis and form an oblique axis.

[0074] Advantageously, monitoring a given partial field of view with a separate camera can facilitate the assignment of camera data to the partial field of view and thus facilitate the interpretation and evaluation of the camera data.

[0075] For example, camera data can be more easily assigned to the at least one component of the global irradiance if it is clear in which field of view it was acquired. In an alternative embodiment, the field of view of at least approximately 360° can be divided into more than two partial fields of view. Furthermore, additional cameras are conceivable that acquire camera data in the additional partial fields of view.

[0076] According to a favorable configuration of the arrangement, at least one first camera, acting as a sky camera, can capture camera data in the first partial field of view, which is oriented toward the sky and forms an upper partial field of view. At least one second camera, acting as a ground camera, can capture camera data in the second partial field of view, which is oriented toward the Earth's surface and forms a lower partial field of view. The cameras are designed, in particular, as fisheye cameras. The upper partial field of view and the lower partial field of view can have a common, substantially vertical axis or an oblique axis, or can be arranged on spaced-apart axes.

[0077] By using multiple cameras, the use of an omnidirectional camera can be advantageously avoided.

[0078] Furthermore, the camera data from each camera can be easily assigned to the upper or lower part of the field of view. The cameras can be specifically configured to monitor the sky and the ground.

[0079] Alternatively, a 360° camera with a field of view of at least approximately 360° around the camera array can capture camera data in the first partial field of view and capture camera data in the second partial field of view. In particular, the first partial field of view can form an upper partial field of view oriented toward the sky, and the second partial field of view can form a lower partial field of view oriented toward the Earth's surface.

[0080] The use of a single camera advantageously eliminates the need for multiple cameras. This simplifies installation. Furthermore, a single camera and the reduced number of cameras minimize potential sources of error, for example, during data transmission, inaccurate camera alignment, and / or calibration of the respective cameras. The camera data can be assigned to the upper or lower partial field of view during the evaluation of the camera data. The cameras used can generate high-resolution and high-quality images or camera data. Alternatively, surveillance cameras can be used. These are cheaper and can deliver images with stronger artifacts. An alternative design could involve an arrangement of cameras and parabolic mirrors.

[0081] In contrast to known arrangements with sky cameras, which can determine cloud heights and thus cloud speeds above the ground, the arrangement according to the invention monitors only a single upper partial field of view, while conventional sky camera arrangements with this range of functions monitor at least two upper partial fields of view and comprise at least two sky cameras.

[0082] In contrast to known arrangements with ground cameras, the arrangement according to the invention monitors only a small section of the ground, so that the ground camera can be arranged at a smaller distance from the ground than with conventional ground camera arrangements.

[0083] In a camera arrangement with a sky camera and a ground camera, the two cameras can be installed at the same location with opposite orientations.

[0084] If the camera arrangement is designed with a single camera, it is automatically arranged at one location.

[0085] Advantageously, with the arrangement according to the invention, the outlay for purchasing and operating hardware can be reduced because the advantages of a cloud camera arrangement and a shadow camera arrangement can be combined. According to a favorable embodiment of the arrangement, at least one evaluation and control device can extract camera data assigned to the sky from the acquired camera data and determine at least one of the following parameters from this camera data assigned to the sky: direct radiation and / or diffuse radiation and / or a global irradiance Gl and / or at least one position of cloud features and / or areas of the sky covered by clouds and / or from cloud positions and / or from the position of cloud features in the camera image between at least two time stamps, an angular velocity of at least one cloud in the camera image.

[0086] Cloud features are defined below as image features that indicate the presence of a cloud. Cloud position is defined below as an estimate of the position of a cloud or cloud cluster, since clouds are not solid objects, and individual clouds are difficult to distinguish within a cloud formation.

[0087] With a camera that only monitors the upper field of view, extracting the camera data associated with the sky is easy, since almost all of this camera's data can be assigned to the sky. For a camera that monitors both parts of the sky and parts of the ground, prior analysis of the camera data can enable assignment to either the sky or the ground.

[0088] At least one evaluation and control device can, with appropriate programming and an appropriate evaluation method, determine the angular velocity of a cloud or of several clouds or of a cloud formation from the camera images. In a possible evaluation method for determining the position of cloud features and / or for calculating the angular velocity of a cloud or of several clouds or of a cloud formation, image features that correspond to the position of the cloud or the positions of the clouds or of the cloud formation can be recognized. To calculate the angular velocity of a cloud or of several clouds or of a cloud formation, a shift Am, An of image features in the camera image in the direction of an x-axis and a y-axis between the times ti = t0 and t2 = t2 + t0 can be determined.

[0089] The shift can be represented by creating difference images di of a color channel of the color channels. A first difference image di can be created from a camera image at a first time ti = t0 and a camera image at a second time t2 = t0 + Δt. Additionally, a second difference image d2 can be created from the camera image at the second time t2 = t0 + Δt and a camera image at a third time ts = t0 + 2Δt.

[0090] The difference images di and d2 can be rectified. Rectification involves projecting the determined values ​​onto a horizontal plane at an unknown height above the camera. This projection produces orthoimages 01 and 02. Image features and their positions are identified from the orthoimages 01 and 02.

[0091] In a further step, the orthoimages 01 and 02 can be converted into binary images bi, b2, where, for example, 2% of the pixels are assigned the value 1 and the remaining 98% of the pixels are assigned the value 0. These 2% of the pixels exhibit the greatest difference in terms of magnitude. This allows strong increases or decreases in this color channel between the times t0, t0+At, t0+2At to be determined. In a further step, these binary images can be compared as a whole using cross-correlation, for example, or the images can be compared region by region using a more refined method. The shift Am, An corresponds to the shift for which the cross-correlation between the binary orthoimages 01 and 02 is maximum. This process can be carried out for at least one color channel. Multiple color channels can also be evaluated in this way.Furthermore, further refinements and appropriate adjustments can be made in the procedure for determining the displacement Am, An of the cloud or clouds.

[0092] In an alternative method, image features and their shift Am, An can also be determined in other ways, for example using SIFT (scale invariant feature transform) or other machine learning methods.

[0093] Using the known time offset t2- z^and Am, An, the angular velocity in both directions x and y can then be calculated as:

[0094] ^x pix / s = m / (t2- ti)

[0095] The direct radiation and / or the diffuse radiation can be determined by at least one evaluation and control device. This can be the same evaluation and control device that already determines the angular velocity of the cloud, or it can be a different evaluation and control device.

[0096] As a basis, the intensity values ​​of the RGB channels of at least one camera in the upper partial field of view or from the camera data assigned to the sky are evaluated by the evaluation and control device. These intensity values ​​can be read directly from the corresponding camera. In one possible evaluation method, a physical camera model is used to calculate the radiation (radiance) received from a specific area of ​​the sky from the intensity values ​​of the RGB channels of the camera image. In addition, physically motivated corrections can be applied to improve the calculation. In an alternative embodiment, the physical camera model can be replaced by a purely statistical machine-learning model.

[0097] In particular, an architecture using a convolutional neural network followed by a fully connected neural network can, with appropriate training, replace or imitate the camera model, or supplement it or adapt it independently.

[0098] In one step of the evaluation process with basic assumptions of the physical camera model, a gamma correction commonly used for cameras can be reversed in order to obtain a linearized RGB image from the RGB image of the respective camera.

[0099] This step can be omitted if the camera in question does not perform gamma correction, so that the gamma correction does not need to be subsequently reversed. This can be the case, for example, if the gamma correction of the camera in question is deactivated or if the camera does not perform gamma correction for other reasons. In a further step of the evaluation process, for example, a pixel-by-pixel assignment of image areas to sky areas can be performed using azimuth and zenith angles. Other assignments are also conceivable instead of a pixel-by-pixel assignment. An angular degree of the azimuth angle can be specified from south via west, north, and east.

[0100] When assigning image regions to sky regions, geometric calibrations of the corresponding camera and the resulting transformations can be applied. Alternatively, the assignment of image regions to sky regions can be performed roughly using azimuth and zenith angles. For example, assignment without the use of calibrations is conceivable. The calibrations and the resulting transformations can be implemented as a machine-learning model and continuously improved.

[0101] In a further step of the evaluation process, the intensities of the color channels of the linearized RGB image can be weighted and summed. This weighting can achieve the most uniform sensitivity of the corresponding camera in the visible wavelength range.

[0102] In a further step of the evaluation process, multiplication by a broadband correction, which takes into account portions of the broadband solar radiation originating from the non-visible wavelength range, can be performed. Furthermore, multiplication by a calibration factor, which takes the sensitivity of the camera into account, is conceivable. Furthermore, the application of at least one correction to account for interference on the measurement, such as lens refraction, image saturation, or the influence of the camera's exposure control, is possible. Additionally or alternatively, applied correction factors, such as the broadband correction, the calibration factor, and the interference correction, can be partially combined or rewritten.Furthermore, these corrections can be replaced or supplemented by statistically determined corrections, for example via machine-based learning, in particular based on image features.

[0103] In a further step of the evaluation process, diffuse and / or direct radiation can be determined from the radiation (radiance) received from various sky regions, for example, by projection, in any horizontal plane or plane inclined to the ground, including a plane facing the ground. This can involve assigning image regions to sky regions and integrating across image regions / sky regions. If necessary, global radiation can also be determined in inclined planes and in planes facing the ground.

[0104] In an alternative embodiment of the method, the substeps, for example the application of a physical camera model and / or the assignment of image areas to sky areas and / or the application of physically motivated corrections and / or the projection into an arbitrary plane, for determining direct and diffuse radiation in an arbitrary plane can be partially or entirely simulated by a so-called machine learning model. In the simplest embodiment of the arrangement, by evaluating the intensities of the RGB channels from the upper partial field of view or from the camera data assigned to the sky, values ​​can be determined that correspond to the sum of diffuse radiation and direct radiation. Extensions would be possible, enabling the determination of separate values ​​for diffuse radiation and direct radiation.

[0105] Advantageously, by determining the direct radiation and / or diffuse radiation, the performance of a solar plant at the location of the arrangement according to the invention can be determined and a solar resource at the location can be assessed. No additional sensors or sensor units, such as pyranometers, are required. The radiation can be determined solely by the at least one camera and its camera data.

[0106] Knowledge of the cloud-covered areas in the upper part of the field of view can advantageously be used to further assess the measured radiation. For example, diffuse radiation may increase due to clouds, and direct radiation may decrease due to clouds. Different weather conditions may result in different radiation conditions at the site. Current and future radiation conditions can be determined, at least in part, by determining cloud positions and cloud speed.

[0107] According to a favorable embodiment of the arrangement, the evaluation and control device can extract camera data associated with the earth's surface from the acquired camera data and determine at least one of the following parameters from these camera data associated with the earth's surface: a radiation reflected at the earth's surface and / or an albedo of the earth's surface and / or at least one cloud shadow position and / or from the cloud shadow positions between at least two time stamps, a speed of at least one cloud above the earth's surface.

[0108] With a camera that monitors only the lower field of view, the extraction of camera data associated with the Earth's surface is easy, since almost all of this camera's data can be assigned to the Earth's ground. For a camera that monitors both parts of the sky and parts of the Earth's ground, prior analysis of the camera data can enable assignment to either the sky or the ground.

[0109] The speed of a cloud or multiple clouds above the ground can be determined by at least one evaluation and control device from the camera images of the lower partial field of view or from the camera data associated with the Earth's surface. This can be one of the evaluation and control devices that evaluates the camera data of the upper partial field of view or the camera data associated with the sky, or it can be another evaluation and control device.

[0110] The corresponding evaluation procedure is similar to that used to determine the angular velocity of clouds from images of the upper partial field of view or from the camera data associated with the sky. In an alternative procedure, image features corresponding to the position of at least one cloud shadow and their displacement Am, An can also be determined in other ways, for example, using SIFT (scale invariant feature transform) or other machine learning methods.

[0111] In a possible evaluation procedure, image features corresponding to the position of a cloud shadow or the positions of several cloud shadows can be detected and a shift Am, An of image features in the camera image in the direction of an x-axis and a y-axis between the times ti= to, t2=to+At, ts= to+2At can be determined.

[0112] These images can be converted into orthoimages using the known elevation profile of the earth's surface in the monitored area and geometric calibrations of the camera. In contrast to the analysis of the upper partial field of view or the analysis of the camera data associated with the sky, the projection height is known. In the corresponding orthoimages, each image pixel thus corresponds to a square sub-area of ​​the monitored area. Difference images can be calculated from the orthoimages converted to grayscale. Other outputs are also possible instead of grayscale. As with the determination of angular velocity, difference images can be converted into binary images. Using cross-correlation, the displacement of image pixels Am, An, which can be assigned to a corresponding displacement Ax, Ay of the cloud shadows in the monitored area, can be determined.The magnitude of this “absolute” speed of the cloud shadows above the ground is then calculated as. where the scaling factor k sc (Unit m / pixel) indicates the known side length of an image pixel in meters. Since the speed of the cloud shadows above the ground also corresponds to the speed of the corresponding cloud above the ground, two sky cameras monitoring different upper partial fields of view are advantageously not required to determine the cloud speed above the ground, as the cloud speed can be easily determined from one lower partial field of view or from the camera data assigned to the Earth's surface. In addition, the use of estimates when calculating the cloud speed can be dispensed with, allowing a reliable and accurate value for the cloud speed above the ground to be calculated.

[0113] In the following, cloud velocity above the ground is defined as the speed of clouds relative to imaginary fixed points on the ground. From the determined cloud velocity and the current cloud position, a future cloud position and a corresponding change in global irradiance in a given area can be advantageously determined or predicted.

[0114] The radiation reflected from the Earth's surface and / or the albedo of the Earth's surface can be determined by at least one evaluation and control device. This can be the same evaluation and control device that already determines another parameter, or it can be a different evaluation and control device.

[0115] The determination of the radiation reflected by the ground is similar to the determination of direct radiation and / or diffuse radiation. As a basis, the intensity values ​​of the RGB channels of at least one camera, which acquires camera data from the lower partial field of view, are evaluated by the corresponding evaluation and control device. These intensity values ​​can be read directly from the corresponding camera if it exclusively monitors the ground. Otherwise, the relevant camera data can be separated beforehand from the irrelevant camera data. In one possible evaluation method, a physical camera model is used to calculate the radiation received from a specific area of ​​the ground from the intensity values ​​of the RGB channels of the camera image. In addition, physically motivated corrections can be applied to improve the calculation.In an alternative embodiment, the physical camera model can be replaced by a purely statistical machine-learning model. In particular, an architecture using a convolutional neural network followed by a fully connected neural network can, with appropriate training, replace, mimic, supplement, or independently adapt the camera model.

[0116] In a step of the evaluation process based on basic assumptions of the physical camera model, a gamma correction commonly used for cameras can be reversed to obtain a linearized RGB image from the respective camera's RGB image. This step can be omitted if the respective camera does not perform gamma correction, thus eliminating the need to subsequently reverse the gamma correction. This can be the case, for example, if the gamma correction of the respective camera is deactivated or if the camera does not perform gamma correction for other reasons.

[0117] In a further step of the evaluation process, for example, a pixel-by-pixel mapping of image regions to ground regions can be performed using the known elevation profile of the Earth's surface in the monitored area. Each image pixel can correspond to a square sub-area of ​​the monitored area. Alternatively, the pixel-by-pixel mapping of image regions to ground regions can be adopted from the cloud velocity determination. Other mappings are also conceivable instead of pixel-by-pixel mapping.

[0118] When mapping image regions to ground regions, geometric calibrations of the corresponding camera and the resulting transformations can be applied. Furthermore, mapping without the use of calibrations is conceivable. The calibrations and the resulting transformations can be implemented as a machine-learning model and continuously improved.

[0119] In a further step of the evaluation process, the intensities of the color channels of the linearized RGB image can be weighted and summed. This weighting can achieve the most uniform sensitivity of the corresponding camera in the visible wavelength range.

[0120] In a further step of the evaluation process, multiplication by a broadband correction can be performed, which takes into account the portion of broadband solar radiation originating from the non-visible wavelength range. Furthermore, multiplication by a calibration factor, which takes the camera's sensitivity into account, is conceivable.

[0121] In addition, it is possible to apply at least one correction to account for interference with the measurement, such as lens refraction, image saturation, or the influence of the camera's exposure control. Additionally or alternatively, applied correction factors, such as the broadband correction, the calibration factor, and the interference correction, can be partially combined or rewritten. Furthermore, these corrections can be replaced or supplemented by statistically determined corrections, for example, using machine-based learning, particularly based on image features.

[0122] In a further step of the evaluation procedure, the radiation incident on a plane and reflected at the ground can also be determined for inclined planes and also for planes directed towards the ground, if required.

[0123] In an alternative embodiment of the evaluation method, the sub-steps, for example the application of a physical camera model and / or the assignment of image areas to sky areas and / or the application of physically motivated corrections and / or a projection into an arbitrary plane to determine the radiation reflected at the ground, can be partially or entirely simulated by a machine learning model.

[0124] Furthermore, in a further step, the current albedo of the ground or a more detailed reflectance of the ground can be derived from the determined reflected radiation, the determined direct radiation and the determined diffuse radiation. Advantageously, by evaluating the camera data from the lower field of view or the camera data assigned to the earth's surface and the upper field of view or the camera data assigned to the sky, it is possible to determine the current albedo or reflectance of the ground in the monitored area, for example due to weather, season or vegetation. This makes it possible to avoid having to resort to a less accurate estimate of the albedo or reflectance of the ground. This enables a better assessment of the solar radiation in this area. Advantageously, the reflectance orthe albedo of the ground and / or the reflected radiation and / or direct radiation and / or the diffuse radiation are given in angular and spectral resolution.

[0125] In addition, the global and diffuse irradiance in any inclined plane, including those facing the ground, can be calculated from the radiation from various regions of the sky and from the angularly and spectrally resolved reflectance of the ground or the albedo. This allows the radiation on the back of each module, especially for bifacial photovoltaic modules, to be calculated individually, taking into account the typically complex geometry of power plants. This setup can be further supported by combining it with a pyranometer.

[0126] The reflectance corresponds to the reflectance of the surface. The reflectance indicates the ratio of the radiant power reflected by a surface to the radiant power incident on the surface.

[0127] An angle-resolved reflectance is understood as information in the sense of a bidirectional reflection distribution function or quantities derived from it, such as a detailed composition of the albedo, in particular a black-sky albedo and white-sky albedo.

[0128] Spectrally resolved reflectance is the ratio of the radiant power reflected by a surface at a specific wavelength or in a specific wavelength range to the radiant power striking the surface at this specific wavelength or in this wavelength range. Furthermore, camera data from the lower field of view or camera data associated with the Earth's surface can be advantageously used to monitor contamination or damage to a solar system and other solar collectors, allowing for cleaning or repairs to be initiated as needed.

[0129] According to a favorable embodiment of the arrangement, at least one evaluation and control device can determine a height of the clouds from the speed of at least one cloud above the earth's surface and the angular speed of at least one cloud in the camera image.

[0130] The calculation of the cloud speed above the ground can be done in the upper part of the field of view or from the camera data assigned to the sky based on the angular velocity v p(-x / s take place:

[0131] This gives the height H2 of the cloud:

[0132] Here, the angle 0 corresponds to the maximum zenith angle up to which the upper field of view of 180° or at least approximately 180° around the camera array is evaluated. N corresponds to the diameter in pixels of the circular image area representing the sky area with a zenith angle less than or equal to 0. The angle 0 and the parameter N can be determined from the camera image of the upper field of view of at least approximately 180° around the camera array. m / s corresponds to the determined speed of the cloud above the ground, and v Pix / s corresponds to the determined angular velocity of the cloud. H2 corresponds to the height of the cloud projected via the camera array or via the at least one camera of the camera array directed towards the sky. Since the distance of the at least one camera from the ground is known, the actual height of the cloud above the ground at its current position can be calculated from the known elevation profile of the monitored area, the current cloud position, and the height of the cloud projected via the camera. Refinement of the calculations is possible.

[0133] In particular, the evaluation and control device can determine a future cloud position using the height of the clouds, the current position of the clouds, and the cloud speed above the earth's surface. From this, future shading or future global irradiance in a given area can be estimated or calculated. This advantageously enables more accurate short-term forecasts of solar radiation to be created with only one camera arrangement at the same location, with the cameras used being installed only a few meters above the ground. This advantageously allows early response to shading or an expected fluctuation in the output of the solar system. Advantageously, the camera data can be determined at a common location, thereby simplifying and reducing the cost of maintenance and operation of the arrangement according to the invention.

[0134] According to a favorable embodiment of the arrangement, at least one evaluation and control device can extrapolate the speed of clouds above the earth's surface and / or the angular speed of clouds in the camera image in time and space.

[0135] Here, both the angular velocity of clouds in the camera image and the speed of clouds above the Earth's surface can be averaged / extrapolated over time and space in order to obtain greater temporal and spatial coverage. This advantageously also makes it possible to determine the cloud height and cloud speed of clouds whose shadows are not (yet) recorded in the lower field of view or by camera data assigned to the Earth's surface. Temporal and spatial extrapolation can compensate for the fact that the lower field of view records a small section and therefore fewer cloud shadows than clouds or cloud features are recorded in the upper part of the field of view. Temporal and spatial extrapolation makes it unnecessary to use the data from one cloud and its shadow for the evaluation. The shadows from other clouds can also be used to determine the cloud height of a cloud recorded in the upper part of the field of view or by camera data assigned to the Earth's surface.Clouds or cloud features captured in the camera data associated with the sky can be used. This analysis is less accurate than using the camera data of a cloud or cloud feature and its shadow for analysis. However, a continuous determination of cloud heights is possible. With known systems, such as lidar systems or ceilometer systems, cloud heights are only determined at specific points.

[0136] According to a favorable embodiment of the arrangement, the at least one evaluation and control device can determine at least one current and / or future value of at least one component of the global irradiance from the camera data and / or the determined parameters in a spectrally and / or angularly resolved manner. In this case, angle-resolved radiation information, in particular the radiance, can be weighted and integrated according to a projection into the plane of interest. The angle-resolved information itself can also be of interest to a user, so that weighting and integration can then be omitted. The current and / or future albedo of the earth's surface can be determined by angle-resolved detection of at least one component of the global radiation.Furthermore, the current and / or future irradiance of radiation incident on a plane with a known inclination to the Earth's surface, for example, the back of a bifacial photovoltaic module, can be advantageously determined. Additional support from a pyranometer or other suitable sensor is possible. Advantageously, no additional sensors such as pyranometers are required to spectrally and / or angularly resolve irradiances of the components of global radiation or to determine irradiances on planes inclined to the Earth's surface. This can reduce the cost of the system.

[0137] According to a favorable embodiment of the arrangement, at least one evaluation and control device can determine at least one component of the global radiation on an inclined surface, in particular a surface with any orientation. This advantageously allows an optimal inclination angle of solar modules, including bifacial photovoltaic modules, to be determined. Alternatively or additionally, given known inclination angles of solar modules, including bifacial photovoltaic modules, a current and / or expected output can be determined.

[0138] Advantageously, the arrangement according to the invention allows virtually every parameter required to determine and predict at least one component of global irradiance to be calculated at a single location using the camera array. No additional sensors or further camera arrays are required. The arrangement according to the invention also allows for very short-term forecasts of solar radiation. At the same time, this setup also allows for improved monitoring of solar power plants or surveillance in other areas, such as airports.The use of an arrangement for determining at least one parameter for determining at least one component of a global irradiance is proposed, wherein camera data are acquired in a field of view of at least approximately 360° around the camera arrangement, wherein information on solar radiation and / or on the position and / or on properties of clouds is derived from the camera data.

[0139] Essentially the same definitions apply to the use of the arrangement as to the arrangement for determining at least one parameter for determining at least one component of a global irradiance; therefore, a repetition of definitions, for example of the cloud characteristics, the angle-resolved reflectance and / or the spectrally resolved reflectance, is omitted.

[0140] Advantageously, when using the arrangement, the spatial field of view of at least approximately 360° around the camera arrangement allows the advantages of an arrangement with a sky camera directed towards the sky, also known as a cloud camera, to be combined with the advantages of an arrangement with a ground camera directed towards the ground, also known as a shadow camera, and thereby compensates for the disadvantages of the sky camera and the ground camera.

[0141] To achieve these advantages, the camera data associated with the spatial field of view of at least approximately 360° around the camera arrangement is evaluated. Furthermore, the camera data from the field of view of at least approximately 360° around the camera arrangement is advantageously simultaneously recorded at a common location and evaluated for this location. By combining these advantages, a camera arrangement with a field of view of at least approximately 360° can be sufficient to capture enough camera data to reliably record and / or predict desired parameters. This eliminates the need for additional cameras at other locations or additional sensor units, thereby reducing costs and the effort required for evaluation.

[0142] An advantage of evaluating the camera data of an upper partial field of view of at least approximately 180° around the camera arrangement or from the evaluation of camera data assigned to the sky is that a large section of the sky can be captured and monitored. In particular, clouds can be detected long before their shadows arrive in the monitored area and corresponding forecasts can be made.

[0143] An advantage of evaluating the camera data from the lower partial field of view of at least approximately 180° around the camera array, or evaluating the camera data associated with the Earth's surface, is that certain parameters, such as cloud speed above the Earth's surface, can be precisely and directly derived from these camera data. The monitored and detectable section of the Earth's surface depends, among other things, on the height at which the at least one camera that captures the lower partial field of view of at least approximately 180° around the camera array is located.

[0144] In order to make a reliable forecast, ground cameras are usually arranged on high towers or ridges in order to enlarge the section of the ground they monitor. Due to the height, clouds floating between the camera and the ground in these arrangements can prevent or complicate monitoring of the ground. Advantageously, a forecast can be determined using camera data from at least one camera directed towards the sky or using camera data assigned to the sky. This means that a large section of the ground is not necessarily required to monitor the ground. Thus, in contrast to known shadow camera arrangements, the camera arrangement can be arranged at a lower height above the ground. For example, the holding arrangement can fix the at least one camera at a distance of 1 - 100 m from the ground, which is typical for albedo measurements.The minimum distance of at least one camera from the ground may depend on the ground conditions. For locations with snow, unmown grass, or crops on the ground, a height of 10 m should be selected, for example, to avoid interference from uneven surfaces. Lower heights are also possible for less densely vegetated surfaces and / or in areas with light snowfall.

[0145] Furthermore, the minimum height can be selected such that gradients of the intensities of the RGB channels of the at least one camera aligned with the ground can be reliably identified, so that the parameters derived therefrom can be determined reliably and accurately.

[0146] A maximum distance of at least one camera, which is aligned to the ground, prevents low-lying clouds from making it difficult to capture camera data. This maximum distance is determined depending on the intended use and location. For example, if clouds at a height of 500 m or more above the camera are of interest, the at least one camera should be mounted at a height of no more than 100 m. If the arrangement is also used to measure the radiation reflected by the ground, a shorter distance is advantageous. As the distance increases, the area included in the measurement of the radiation reflected by the ground also increases. This area can potentially be affected by unwanted influences such as trees, reflective objects, land use, etc.

[0147] Because the camera array is fixed at a maximum height of 100 m, the costs for the mounting system can be reduced. Furthermore, such a fixed camera array can be easily and quickly set up anywhere, allowing for flexible deployment.

[0148] Alternatively, a drone can simply fly at this altitude and can also be deployed flexibly at multiple locations. This also makes it possible to change locations once the desired parameters have been calculated.

[0149] By utilizing a low-level camera setup or a drone, the suitability of a site for a solar farm, for example, can be easily and cost-effectively assessed. No tower or other tall building is required.

[0150] Advantageously, the camera data can be acquired at a common location using the arrangement according to the invention, eliminating the need to transfer camera data between two locations and convert the data from one location to the other. In particular, by reducing the number of cameras or the number of camera arrangements, hardware expenditure and thus hardware costs can be reduced.According to a favorable embodiment of the use of the arrangement, the field of view of the camera arrangement at a predetermined location can be composed of a first partial field of view and a second partial field of view, each of at least approximately 180° around the camera arrangement, and camera data in the first partial field of view can be acquired with at least one first camera and camera data in the second partial field of view can be acquired with at least one second camera, wherein the two partial fields of view of the cameras complement each other to form a spatial field of view of at least approximately 360°. This can advantageously facilitate the assignment of camera data to the partial fields of view.

[0151] In particular, at least one first camera acting as a sky camera can capture camera data in the first partial field of view, which is oriented toward the sky and forms an upper partial field of view. At least one second camera acting as a ground camera can capture camera data in the second partial field of view, which is oriented toward the Earth's surface and forms a lower partial field of view.

[0152] Alternatively, using a 360° camera with a field of view of at least approximately 360° around the camera arrangement, camera data can be captured in the first partial field of view and camera data in the second partial field of view. In particular, the first partial field of view can form an upper partial field of view oriented towards the sky, and the second partial field of view can form a lower partial field of view oriented towards the earth's surface. In this case, in particular, the first partial field of view can form an upper partial field of view oriented towards the sky, and the second partial field of view can form a lower partial field of view oriented towards the earth's surface. By using one camera, the use of multiple cameras can advantageously be dispensed with. This can simplify installation.Furthermore, by reducing the number of cameras to a single camera, potential sources of error can be minimized, for example, during data transmission, or due to inaccurate camera alignment and / or calibration of the respective cameras. Assigning the camera data to the upper or lower partial field of view can be done during the camera data analysis.

[0153] Advantageously, the camera data of the respective cameras can be easily assigned to the upper partial field of view or the lower partial field of view. In contrast to known arrangements with ground cameras, the arrangement according to the invention only monitors a small section of the ground, so that the ground camera, or the camera that captures camera data assigned to the ground, can be positioned at a closer distance to the ground than with conventional ground camera arrangements.

[0154] When implementing a camera arrangement with a sky camera and a ground camera, the two cameras can be installed at the same location with opposite orientations.

[0155] Advantageously, when using the arrangement according to the invention, the outlay for purchasing and operating hardware can be reduced because the advantages of a cloud camera arrangement and a shadow camera arrangement can be combined. According to a favorable embodiment of the use of the arrangement, camera data assigned to the sky can be extracted from the recorded camera data, and at least one of the following parameters can be determined from this camera data assigned to the sky: a direct irradiance and / or a diffuse radiation and / or a global irradiance and / or at least one position of cloud features and / or areas of the sky covered by clouds and / or from cloud positions WP and / or from the position of cloud features in the camera image between at least two time stamps, an angular velocity of at least one cloud in the camera image can be determined.

[0156] In this case, image features corresponding to the position of the cloud or the positions of the clouds can be detected from the captured camera data of the upper partial field of view or from the camera data assigned to the sky, and a shift Am, An of image features in the camera image in the direction of an x-axis and a y-axis between the times ti =to and t2=to+At can be determined.

[0157] The shift can be represented by creating difference images di of a color channel from the existing color channels. A first difference image di can be created from a camera image at a first time ti=to and a camera image at a second time t2=to+At. In addition, a second difference image d2 can be created from the camera image at the second time t2=to+2At and a camera image at a third time ts=to+2At. The difference images di and d2 can be rectified. Rectification here means that the determined values ​​are projected onto a horizontal plane with an unknown height above the camera. This projection results in orthoimages 01 and 02. Image features and their positions are identified from the orthoimages 01 and 02.In a further step, the orthoimages 01 and 02 can be converted into binary images bi, b2, where, for example, 2% of the pixels are assigned the value 1 and the remaining 98% are assigned the value 0. These 2% of the pixels exhibit the largest difference in magnitude. This allows strong increases or decreases in this color channel between the times t0, t0+At, t0+2At to be determined. In a further step, these binary images can be compared as a whole using cross-correlation, for example, or the images can be compared region by region using a more refined method.

[0158] The shift Am, An corresponds to the shift for which the cross-correlation between the binary orthoimages O1 and O2 is maximized. This procedure can be performed for at least one color channel. Multiple color channels can also be evaluated in this way. Furthermore, further refinements and appropriate adjustments can be made to the procedure for determining the shift Am, An of the cloud(s).

[0159] In an alternative method, image features and their shift Am, An can also be determined in other ways, for example using SIFT (scale invariant feature transform) or other machine learning methods.

[0160] Using the known time offset t2- ti and Am, An, the angular velocity in both directions x and y can then be calculated as:

[0161] The speed of the cloud above the ground can be determined from the angular velocity

[0162] ^m / s ^pix / s^ tun 9 H2I N Here, the angle 0 corresponds to the maximum zenith angle up to which the upper spatial partial field of view of at least approximately 180° around the camera arrangement is evaluated. N corresponds to the diameter in pixels of the circular image area, which represents the sky area with a zenith angle less than or equal to 0. The angle 0 and the parameter N can be determined from the camera image of the upper partial field of view of at least approximately 180° around the camera arrangement or from the camera data assigned to the sky. v Pix / s corresponds to the determined angular velocity of the cloud. H2 corresponds to the height of the cloud projected over the camera array or over at least one camera of the camera array that is directed toward the sky. This height is unknown for known cloud camera arrays and is determined by measurement data from other measurement arrays, sometimes at other locations.

[0163] The basis for determining the direct radiation and / or diffuse radiation is the intensity values ​​of the RGB channels of at least one camera monitoring the upper partial field of view or areas of the upper partial field of view. These intensity values ​​can be read directly from the corresponding camera.

[0164] In one possible evaluation method, a physical camera model is used to calculate the radiation (radiance) received from a specific area of ​​the sky from the intensity values ​​of the RGB channels of the camera image. Additionally, physically motivated corrections can be applied to improve the calculation. In an alternative embodiment, the physical camera model can be replaced by a purely statistical machine-learning model. In particular, an architecture using a convolutional neural network followed by a fully connected neural network can, with appropriate training, replace or supplement the physical camera model, or imitate or independently adapt it.

[0165] In a step of the evaluation process based on basic assumptions of the physical camera model, a gamma correction commonly used for cameras can be reversed to obtain a linearized RGB image from the respective camera's RGB image. This step can be omitted if the respective camera does not perform gamma correction, thus eliminating the need to subsequently reverse the gamma correction. This can be the case, for example, if the gamma correction of the respective camera is deactivated or if the camera does not perform gamma correction for other reasons.

[0166] In a further step of the evaluation process, for example, a pixel-by-pixel assignment of image areas to sky regions can be performed using azimuth and zenith angles. Instead of a pixel-by-pixel assignment, other assignments are also conceivable. A degree of the azimuth angle can be specified from south to west, north, and east.

[0167] When assigning image regions to sky regions, geometric calibrations of the corresponding camera and transformations based on them can be applied. Alternatively, the assignment of image regions to sky regions can be performed roughly using azimuth and zenith angles. For example, an assignment without the use of calibrations is conceivable. The calibrations and the transformations based on them can be implemented as a machine-based learning model and continuously improved. In a further step of the evaluation process, the intensities of the color channels of the linearized RGB image can be weighted and summed. This weighting can achieve the most uniform sensitivity possible for the corresponding camera in the visible wavelength range.

[0168] In a further step of the evaluation process, multiplication by a broadband correction can be performed, which takes into account the portion of broadband solar radiation originating from the non-visible wavelength range. Furthermore, multiplication by a calibration factor, which takes the camera's sensitivity into account, is conceivable.

[0169] In addition, it is possible to apply at least one correction to account for interference with the measurement, such as lens refraction, image saturation, or the influence of the camera's exposure control. Additionally or alternatively, applied correction factors, such as the broadband correction, the calibration factor, and the interference correction, can be partially combined or rewritten. Furthermore, these corrections can be replaced or supplemented by statistically determined corrections, for example, using machine-based learning, particularly based on image features.

[0170] In a further step of the evaluation process, diffuse and / or direct radiation can be determined from the radiation (radiance) received from various sky regions, for example, by projection, in any horizontal plane or plane inclined to the ground, including a plane facing the ground. This can involve assigning image regions to sky regions and integrating across image regions / sky regions. If necessary, the global irradiance can also be determined in inclined planes and in planes facing the ground.

[0171] In an alternative embodiment of the method, the substeps (application of a physical camera model, assignment of image areas to sky areas, application of physically motivated corrections, projection into an arbitrary plane) for determining direct and diffuse radiation in an arbitrary plane can be partially or entirely simulated by a machine learning model.

[0172] In the simplest version of the setup, values ​​corresponding to the sum of diffuse radiation and direct radiation can be determined by evaluating the intensities of the RGB channels from the upper part of the field of view or from the camera data associated with the ground. Extensions are possible, allowing the determination of separate values ​​for diffuse radiation and direct radiation.

[0173] Advantageously, by determining the direct radiation and / or diffuse radiation, the performance of a solar plant at the location of the arrangement according to the invention can be determined, and a solar resource at the location can be assessed. The radiation can be determined using only the at least one camera and its camera data, as well as an evaluation and control device. No additional sensors or similar devices are required.

[0174] Knowledge of the cloud-covered areas of the sky in the upper part of the field of view can be advantageously used to further assess the measured radiation. For example, diffuse radiation may increase due to clouds, and direct radiation may decrease due to clouds. Different weather conditions may result in different radiation conditions at the location. Current and future radiation conditions can be determined, at least in part, by determining cloud positions and cloud speed.

[0175] According to a favorable embodiment of the use of the arrangement, a radiation reflected at the earth's surface and / or an albedo of the earth's surface and / or at least one cloud shadow position and / or a speed of at least one cloud above the earth's surface can be determined from the recorded camera data of the lower partial field of view or from the camera data assigned to the earth's surface and / or from the cloud shadow positions between at least two time stamps.

[0176] The speed of a cloud or several clouds above the ground can be determined from the camera images of the lower field of view or from the camera data assigned to the earth's surface.

[0177] The corresponding evaluation procedure is similar to that used to determine the angular velocity of clouds from images of the upper partial field of view or from the camera data assigned to the sky.

[0178] In an alternative method, image features corresponding to the position of at least one cloud shadow and their displacement Am, An can also be determined in other ways, for example, using SIFT (scale invariant feature transform) or other machine learning methods. In one possible method, image features corresponding to the position of one or more cloud shadows can be detected, and a displacement Am, An of image features in the camera image along an x-axis and a y-axis between the times ti = t0, t2 = t0+At, ts = t0+2At can be determined.

[0179] The shift can be represented by creating difference images di of a color channel from the existing color channels. A first difference image di can be created from a camera image at a first time ti=to and a camera image at a second time t2=to+At. In addition, a second difference image d2 can be created from the camera image at the second time t2=to+At and a camera image at a third time ts=to+2At. The difference images di and d2 can be rectified. Rectification here means that the images are projected using the known elevation profile of the earth's surface of the monitored area and geometric calibrations of the camera at ground level below which the camera is projected. This projection produces orthoimages 01 and 02. Image features and their positions are identified from the orthoimages 01 and 02.In this case, the projection height is known, unlike the evaluation of the upper partial field of view of at least approximately 180° around the camera array. In the corresponding orthoimages, each image pixel thus corresponds to a square sub-area of ​​the monitored area. Difference images can be calculated from the orthoimages converted to grayscale. Other outputs are also possible instead of grayscale.

[0180] As with the determination of angular velocity, difference images can be converted into binary images. For example, 2% of the pixels can be assigned the value 1 and the remaining 98% of the pixels the value 0. These 2% of the pixels exhibit the largest difference in magnitude. This allows for the detection of strong increases or decreases in this color channel between the times t0, t0+At, t0+2At. In a further step, these binary images can be compared as a whole using methods such as cross-correlation, or the images can be compared region by region using a more sophisticated method.

[0181] The displacement Am, An of the image pixels corresponds to the displacement for which the cross-correlation between the binary orthoimages O1 and O2 is maximum. The displacement Am, An of the image pixels can be assigned to a corresponding displacement Ax, Ay of the cloud shadows in the monitored area. This process can be performed for at least one color channel. Multiple color channels can also be evaluated in this way. Furthermore, further refinements and appropriate adjustments can be made to the process for determining the displacement Am, An of the image pixels of the cloud shadow(s).

[0182] The magnitude of this “absolute” speed of the cloud shadows above the ground is then calculated as where the scaling factor k sc (Unit m / pixel) indicates the known side length of an image pixel in meters.

[0183] Since the speed of the cloud shadows above the ground also corresponds to the speed of the corresponding cloud above the ground, two sky cameras monitoring different upper partial fields of view are advantageously not required to determine the cloud speed above the ground, as the cloud speed can be easily determined from one of the lower partial fields of view or the camera data associated with the Earth's surface. Furthermore, the evaluation of the lower partial field of view provides more additional information than the evaluation of another upper partial field of view. Furthermore, the use of estimates when calculating the cloud speed can be dispensed with, allowing a reliable and accurate value for the cloud speed above the ground to be calculated.

[0184] In the following, cloud velocity above the ground is defined as the speed of clouds relative to imaginary fixed points on the ground. From the determined cloud velocity and the current cloud position, a future cloud position and a corresponding change in global irradiance in a given area can be advantageously determined or predicted.

[0185] The radiation reflected from the Earth's surface and / or the Earth's surface albedo can also be determined. The determination of the radiation reflected from the Earth's surface is similar to the determination of direct radiation and / or diffuse radiation.

[0186] The intensity values ​​of the RGB channels of at least one camera in the lower part of the field of view or the camera data associated with the Earth's surface are evaluated as a basis. These intensity values ​​can be read directly from the corresponding camera or from the camera data associated with the Earth's surface.

[0187] In one possible evaluation method, a physical camera model is used to calculate the radiation received from a specific area of ​​the ground from the intensity values ​​of the RGB channels of the camera image. Additionally, physically motivated corrections can be applied to improve the calculation. In an alternative embodiment, the physical camera model can be replaced by a purely statistical machine-learning model. In particular, an architecture using a convolutional neural network followed by a fully connected neural network can, with appropriate training, replace or supplement the camera model, or imitate or independently adapt it.

[0188] In a step of the evaluation process based on basic assumptions of the physical camera model, a gamma correction commonly used for cameras can be reversed to obtain a linearized RGB image from the respective camera's RGB image. This step can be omitted if the respective camera does not perform gamma correction, thus eliminating the need to subsequently reverse the gamma correction. This can be the case, for example, if the gamma correction of the respective camera is deactivated or if the camera does not perform gamma correction for other reasons.

[0189] In a further step of the evaluation process, for example, a pixel-by-pixel assignment of image areas to ground areas can be performed using the known elevation profile of the earth's surface in the monitored area. Each image pixel can correspond to a square sub-area of ​​the monitored area.

[0190] Alternatively, the pixel-by-pixel mapping of image regions to ground regions can be adopted from the cloud velocity determination. Instead of pixel-by-pixel mapping, other mappings are also conceivable. When mapping image regions to ground regions, geometric calibrations of the corresponding camera and the resulting transformations can be applied. Furthermore, mapping without the use of calibrations is conceivable. The calibrations and the resulting transformations can be implemented as a machine-learning model and continuously improved.

[0191] In a further step of the evaluation process, the intensities of the color channels of the linearized RGB image can be weighted and summed. This weighting can achieve the most uniform sensitivity of the corresponding camera in the visible wavelength range.

[0192] In a further step of the evaluation process, multiplication by a broadband correction can be performed, which takes into account the portion of broadband solar radiation originating from the non-visible wavelength range. Furthermore, multiplication by a calibration factor, which takes the camera's sensitivity into account, is conceivable.

[0193] In addition, it is possible to apply at least one correction to account for interference with the measurement, such as lens refraction, image saturation, or the influence of the camera's exposure control. Additionally or alternatively, applied correction factors, such as the broadband correction, the calibration factor, and the interference correction, can be partially combined or rewritten.

[0194] Furthermore, these corrections can be replaced or supplemented by statistically determined corrections, for example, using machine learning, particularly based on image features. In a further step of the evaluation process, the radiation incident on a plane and reflected by the ground can also be determined for inclined planes and for planes directed toward the ground, if necessary.

[0195] In an alternative embodiment of the method, the substeps for determining the radiation reflected at the ground, for example the application of a physical camera model and / or the assignment of image areas to sky areas and / or the application of physically motivated corrections and / or the projection into an arbitrary plane, can be partially or entirely simulated by a machine learning model.

[0196] Furthermore, in a further step, the current albedo of the ground or a more detailed reflectance of the ground can be derived from the determined reflected radiation, the determined direct radiation and the determined diffuse radiation.

[0197] Advantageously, by evaluating the camera data of the lower partial field of view of at least approximately 180° around the camera arrangement or the camera data assigned to the earth's surface and the upper partial field of view of at least approximately 180° around the camera arrangement or the camera data assigned to the sky, it is possible to determine the current, for example weather-related, seasonal, or vegetation-related albedo or reflectance of the ground in the monitored area. This eliminates the need to rely on a less accurate estimate of the albedo or reflectance of the ground. This can enable a better assessment of the solar radiation in this area. Advantageously, the reflectance or albedo of the ground and / or the reflected radiation and / or direct radiation and / or diffuse radiation can be specified with angular resolution and spectral resolution.

[0198] In addition, the global and diffuse irradiance in any inclined plane, including those facing the ground, can be calculated from the radiation from various regions of the sky and from the angularly and spectrally resolved reflectance of the ground, or the albedo. This allows the radiation on the back of each module, especially for bifacial photovoltaic modules, to be calculated individually, taking into account the typically complex geometry of power plants. This setup can be further supported by combining it with a pyranometer.

[0199] The reflectance corresponds to the reflectance of the surface. The reflectance indicates the ratio of the radiant power reflected by a surface to the radiant power incident on the surface.

[0200] An angle-resolved reflectance is understood as information in the sense of a bidirectional reflection distribution function or quantities derived from it, such as a detailed composition of the albedo, in particular a black-sky albedo and white-sky albedo.

[0201] Spectrally resolved reflectance is the ratio of the radiant power reflected by a surface at a specific wavelength or in a specific wavelength range to the radiant power incident on the surface at this specific wavelength or in this wavelength range. Furthermore, the camera data from the lower field of view can be advantageously used to monitor contamination or damage to photovoltaic systems and other solar collectors, allowing for cleaning or repairs to be initiated as needed.

[0202] Advantageously, by determining the direct radiation and / or diffuse radiation together with the reflected radiation, the performance of a solar plant at the location of the arrangement according to the invention can be determined and a solar resource at the location can be assessed. No additional sensors or sensor units, such as pyranometers, are required. The radiation can be determined solely by the at least one camera and its camera data.

[0203] According to a favorable embodiment of the use of the arrangement, a height of the clouds can be determined from the speed of at least one cloud above the earth's surface and the angular velocity of at least one cloud in the camera image.

[0204] The calculation of the cloud velocity above the ground can be carried out in the upper partial field of view of at least approximately 180° around the camera arrangement based on the angular velocity v p(-x / s take place:

[0205] ^m / s ^pixei / s^ täfl Q H2 /

[0206] This gives the height H2 of the cloud:

[0207] Here, the angle 0 corresponds to the maximum zenith angle up to which the upper partial field of view of at least approximately 180° around the camera array is evaluated. N corresponds to the diameter in pixels of the circular image area, which represents the sky area with a zenith angle less than or equal to 0.

[0208] The angle 0 and the parameter N can be determined from the camera image of the upper partial field of view of at least approximately 180° around the camera arrangement. v m / s corresponds to the determined speed of the cloud above the ground and v Pix / s corresponds to the determined angular velocity of the cloud. H2 corresponds to the height of the cloud projected via the camera array or via the at least one camera of the camera array directed towards the sky. Since the distance of the at least one camera from the ground is known, the actual height of the cloud above the ground at its current position can be calculated from the known elevation profile of the monitored area, the current cloud position, and the height of the cloud projected via the camera. Refinement of the calculations is possible.

[0209] In particular, a future cloud position can be determined using the height of the clouds, the current position of the clouds, and the cloud speed above the earth's surface. From this, future shading or future global irradiance in a given area can be estimated or calculated and thus predicted. This advantageously allows more accurate short-term forecasts of solar radiation to be created with only one camera arrangement at the same location, with at least one camera being installed only a few meters above the ground. This advantageously makes it possible to react early to shading or an expected fluctuation in the output of the solar system. Advantageously, the camera data can be determined at a common location, thereby simplifying and reducing the cost of maintenance and operation of the arrangement according to the invention.Depending on the advantageous design of the arrangement, the speed of clouds above the Earth's surface and the angular speed of clouds in the camera image can be extrapolated temporally and / or spatially.

[0210] Here, both the angular velocity of clouds in the camera image and the speed of clouds above the Earth's surface can be averaged and / or extrapolated over time and space in order to obtain greater temporal and spatial coverage. This advantageously also makes it possible to determine the cloud height and cloud speed of clouds whose shadows are not (yet) captured in the lower partial field of view of at least approximately 180° around the camera arrangement. Temporal and spatial extrapolation can compensate for the fact that the lower field of view captures a small section and therefore fewer cloud shadows than clouds are captured in the upper partial field of view. Temporal and spatial extrapolation makes it unnecessary to use the data from one cloud and its shadow for the evaluation.The shadows of other clouds can also be used to determine the cloud height of a cloud captured in the upper part of the field of view, at least approximately 180° around the camera array. This analysis is less accurate than using the camera data of a cloud and its shadow for the analysis. However, a continuous determination of cloud heights is possible. With known systems, such as lidar systems or ceilometer systems, cloud heights are only determined at specific points.

[0211] According to a favorable embodiment of the arrangement, at least one current and / or future value of at least one component of the global irradiance can be determined spectrally and / or angularly resolved from the camera data and / or the determined parameters. In this case, angle-resolved radiation information, in particular the radiance, can be weighted and integrated according to a projection into the plane of interest.

[0212] The angle-resolved information itself can also be of interest to a user, so that weighting and integration can then be omitted. By means of angle-resolved detection of at least one component of the global irradiance, the current and / or future albedo of the earth's surface can be determined. Furthermore, the current and / or future irradiance of radiation incident on a plane with a known inclination to the earth's surface, for example the back of a bifacial photovoltaic module, can be advantageously determined. Additional support from a pyranometer or another suitable sensor is possible. Advantageously, no further sensors, such as pyranometers, are required to resolve the irradiance of the components of the global irradiance in a spectral and / or angular manner or to determine irradiance on planes inclined to the earth's surface.

[0213] According to a favorable embodiment of the use of the arrangement, the at least one component of the global irradiance can be determined on an inclined, in particular on an arbitrarily oriented surface. This advantageously makes it possible to determine an optimal angle of inclination of solar modules, including bifacial photovoltaic modules. Alternatively or additionally, given known angles of inclination of solar modules, including bifacial photovoltaic modules, a current and / or an expected output can be determined. A method for determining at least one parameter for determining at least one component of a global irradiance is proposed, wherein camera data is recorded at a common location in a field of view of at least approximately 360° around a camera arrangement. Information on solar radiation and / or the position and / or properties of clouds is derived from the camera data.

[0214] In particular, the method may be a computer-implemented method.

[0215] Essentially the same definitions apply to the method for determining at least one parameter for determining at least one component of a global irradiance as to the use of the arrangement and to the arrangement for determining at least one parameter for determining at least one component of a global irradiance.

[0216] Therefore, we will not repeat the definition of, for example, cloud characteristics, angle-resolved reflectance and spectrally resolved reflectance at this point.

[0217] Since the evaluation steps of the method essentially correspond to the evaluation steps of the device application, they will also be omitted below. For details of the method steps, reference is made to the description of the use of the arrangement. Further evaluation is also possible with evaluation results with different timestamps or with evaluation results from a different color channel. In this case, evaluation results of the upper partial field of view of at least approximately 180° around the camera arrangement or from the camera data assigned to the sky and evaluation results of the lower partial field of view of at least approximately 180° around the camera arrangement or from the camera data assigned to the earth's surface can be advantageously combined.

[0218] As a result, it is advantageously possible to dispense with the use of estimated values ​​or values ​​from external data sources in order to determine most of the parameters for determining at least one component of a global irradiance, whereby the determination of the parameters for a given location is more accurate and reliable than with conventional methods for detecting and / or predicting at least one parameter for determining and / or predicting at least one component of a global irradiance, which methods rely on estimated values ​​and values ​​from external data sources.

[0219] Advantageously, in the method, by evaluating the at least approximately 360° field of view of the camera arrangement, the advantages of an arrangement with a sky camera directed towards the sky, also known as a cloud camera, can be combined with the advantages of an arrangement with a ground camera directed towards the ground, also known as a shadow camera, and the disadvantages of the sky camera and the cloud camera can be compensated.

[0220] To achieve these advantages, the camera data assigned to the respective partial field of view is evaluated. Furthermore, the camera data of the respective partial fields of view are advantageously recorded at a common location, particularly simultaneously. Image features of one or more color channels of the respective partial field of view, which are created by clouds and cloud shadows and / or by radiation incident on the at least one lens of the at least one camera, can be evaluated.

[0221] Furthermore, the intensity values ​​of one or more color channels of the respective partial field of view can be evaluated. The evaluation results of individual color channels can be compared with the evaluation results of other color channels or with evaluation results with different timestamps.

[0222] By combining these advantages, a camera array with at least a nearly 360° spatial field of view can be sufficient to capture enough camera data to reliably measure and / or predict desired parameters. This eliminates the need to evaluate camera data from additional cameras at different locations or to evaluate measurement data from additional sensor units, thus reducing costs and effort for analysis.

[0223] An advantage of analyzing camera data from an upper partial field of view is that a large section of the sky can be captured and monitored. In particular, clouds can be detected and forecasted long before their shadows arrive in the monitored area.

[0224] One advantage of analyzing camera data from a lower partial field of view, or the camera data associated with the Earth's surface, is that certain parameters, such as cloud speed above the Earth's surface, can be precisely and directly extracted from this data. The monitored and captured section of the Earth's surface depends, among other things, on the height at which the at least one camera capturing the lower partial field of view is located.

[0225] Advantageously, a prediction can be determined using camera data from the upper partial field of view or camera data assigned from the sky, whereby a large section of the ground is not necessarily required to monitor the ground, so that the camera arrangement can be arranged at a lower height above the ground, in contrast to known shadow camera arrangements.

[0226] According to a favorable embodiment of the method, the field of view of the camera arrangement at a given location can be composed of a first partial field of view and a second partial field of view, each at least approximately 180° around the camera arrangement. Camera data in the first partial field of view can be captured with at least one first camera, and camera data in the second partial field of view can be captured with at least one second camera, with the two partial fields of view of the cameras complementing each other to form a field of view of at least approximately 360°.

[0227] According to a favorable embodiment of the method, with the at least one first camera acting as a sky camera, camera data can be acquired in the first partial field of view, which is oriented towards the sky and forms an upper partial field of view. With the at least one second camera acting as a ground camera, camera data can be acquired in the second partial field of view, which is oriented towards the earth's surface and forms a lower partial field of view. Alternatively, with a 360° camera with a field of view of at least approximately 360° around the camera arrangement, camera data can be acquired in the first partial field of view and camera data KDE can be acquired in the partial field of view. In particular, the first partial field of view can form an upper partial field of view oriented towards the sky, and the second partial field of view can form a lower partial field of view oriented towards the earth's surface.

[0228] In this case, the camera data of the respective cameras can advantageously be easily assigned to the upper partial field of view or the lower partial field of view. The method according to the invention advantageously reduces the cost of purchasing and operating hardware, as the advantages of a cloud camera arrangement and a shadow camera arrangement can be combined.

[0229] According to a favorable embodiment of the method, camera data associated with the sky can be extracted from the acquired camera data, and at least one of the following parameters can be determined from these camera data associated with the sky: a direct radiation and / or a diffuse radiation and / or a global irradiance and / or areas of the sky covered by clouds and / or at least one cloud position and / or from cloud positions and / or from the position of cloud features in the camera image between at least two time stamps, an angular velocity of at least one cloud in the camera image can be determined.

[0230] Advantageously, by determining the direct radiation and / or diffuse radiation, the performance of a solar plant at the location of the arrangement according to the invention can be determined, and a solar resource at the location can be assessed. The radiation can be determined based solely on camera data, without additional measurement data from sensors.

[0231] Knowledge of the cloud-covered areas of the sky in the upper part of the field of view can be advantageously used to further assess the measured radiation. For example, diffuse radiation may increase due to clouds, and direct radiation may decrease due to clouds. Different weather conditions may result in different radiation conditions at the site.

[0232] Current and future radiation conditions can be determined, at least in part, by determining cloud positions and cloud speed.

[0233] For further details, refer to the use of the array to determine a parameter.

[0234] According to a favorable embodiment of the method, camera data associated with the earth's surface can be extracted from the acquired camera data, and at least one of the following parameters can be determined from these camera data associated with the earth's surface: a radiation reflected at the earth's surface and / or an albedo of the earth's surface and / or at least one cloud shadow position and / or a speed of at least one cloud above the earth's surface from the cloud shadow positions between at least two time stamps.

[0235] The speed of a cloud or multiple clouds above the ground can be determined using the method according to the invention from the camera images of the lower partial field of view or from the camera data associated with the Earth's surface. The corresponding evaluation method is similar to that used to determine the angular velocity of clouds from images of the upper partial field of view or from the camera data associated with the sky.

[0236] In an alternative method, image features corresponding to the position of at least one cloud shadow and their displacement Am, An can also be determined in other ways, for example using SIFT (scale invariant feature transform) or other machine learning methods.

[0237] For further details, refer to the use of the array to determine a parameter.

[0238] Advantageously, by determining the direct radiation and / or diffuse radiation together with the reflected radiation, the performance of a solar plant at the location of the arrangement according to the invention can be determined and a solar resource at the location can be assessed. No additional sensors or sensor units, such as pyranometers, are required. The radiation can be determined solely by the at least one camera and its camera data.

[0239] According to a favorable embodiment of the method, a height of the clouds can be determined from the speed of at least one cloud above the earth's surface and the angular velocity of at least one cloud in the camera image.

[0240] For further details, reference is made to the use of the arrangement to determine a parameter. In particular, a future cloud position can be determined using the height of the clouds, the current position of the clouds and the cloud speed above the earth's surface. From this, future shading or future global irradiance in a given area can be estimated or calculated. This advantageously enables more accurate short-term forecasts of solar radiation to be created with only one camera arrangement at the same location, with at least one camera being installed only a few meters above the ground. This advantageously allows early response to shading or an expected fluctuation in the output of the solar system.

[0241] With a favorable design of the method, the speed of clouds above the Earth's surface and the angular velocity of clouds in the camera image can be extrapolated temporally and spatially.

[0242] This allows both the angular velocity of clouds in the camera image and the velocity of clouds above the Earth's surface to be temporally and spatially averaged and / or extrapolated to obtain greater temporal and spatial coverage. This advantageously also allows for the determination of cloud height and cloud velocity for clouds whose shadows are not (yet) captured in the lower field of view.

[0243] Temporal and spatial extrapolation can compensate for the fact that the lower field of view captures a smaller section and therefore fewer cloud shadows than clouds in the upper part of the field of view. Temporal and spatial extrapolation makes it unnecessary to use the data from one cloud and its shadow for analysis. The shadows of other clouds can also be used to determine the cloud height of a cloud captured in the upper part of the field of view. This analysis is less accurate than using the camera data from one cloud and its shadow for analysis. However, it does allow for continuous determination of cloud heights.

[0244] According to a favorable embodiment of the method, at least one current and / or future value of at least one component of the global irradiance can be determined spectrally and / or angularly resolved from the camera data and / or the determined parameters.

[0245] Here, angle-resolved radiation information, in particular the radiance, can be weighted and integrated according to a projection into the plane of interest.

[0246] The angle-resolved information itself can also be of interest to a user, so that weighting and integration can then be omitted. By detecting at least one component of the global radiation with angle resolution, the current and / or future albedo of the Earth's surface can be determined. Furthermore, the current and / or future irradiance of radiation incident on a plane with a known inclination to the Earth's surface, for example the back of a bifacial photovoltaic module, can be advantageously determined. Additional support from a pyranometer or another suitable sensor is possible. Advantageously, no further sensors, such as pyranometers, are required to resolve the irradiance of the components of the global radiation with spectral and / or angular resolution or to determine irradiance on planes inclined to the Earth's surface.

[0247] According to a favorable embodiment of the method, at least one component of the global irradiance can be determined on an inclined surface. This advantageously allows an optimal tilt angle of solar modules, including bifacial photovoltaic modules, to be determined. Alternatively or additionally, given known tilt angles of solar modules, including bifacial photovoltaic modules, a current and / or expected output can be determined.

[0248] The arrangement according to the invention, the use of the arrangement according to the invention, and the method according to the invention can be used to predict global irradiance and / or to predict components of global irradiance at specific areas of the Earth's surface based on the cloud position and the inclination of the surface onto which the global irradiance impinges. Thus, the arrangement according to the invention, the use of the arrangement according to the invention, and the method according to the invention can be used to create very short-term forecasts of solar radiation.

[0249] These forecasts have been used to operate self-sufficient microgrids more efficiently through the targeted control of storage systems or generators. In addition, such forecasts can support the operation of distribution grids and the marketing of solar power generation. Furthermore, the precise and angle-resolved measurement of radiation reflected from the ground and radiation from the sky can improve the monitoring of photovoltaic power plants. This will allow bifacial power plants, in particular, to be technically monitored more effectively, with less effort, and in an automated manner.

[0250] The arrangement according to the invention, the use of the arrangement according to the invention, and the method according to the invention can also provide input data for numerical weather models or for combined forecast models incorporating satellite data by monitoring cloud cover and can therefore be of interest to private and public weather services. The arrangement according to the invention, the use of the arrangement according to the invention, and the method according to the invention can also contribute to more cost-effective and comprehensive monitoring of the airspace, for example, above airports, by monitoring cloud cover and cloud height.

[0251] Furthermore, a computer program or a computer program product is proposed, comprising instructions which cause a device according to the invention to carry out a method according to the invention for determining at least one parameter for determining at least one component of a global irradiance Gl.

[0252] Furthermore, a computer program or a computer program product is proposed, comprising instructions which, when the computer program is executed by a computer, cause the computer to carry out a method for determining at least one parameter for determining at least one component of a global irradiance Gl, comprising capturing camera data KDH, KDE from a camera arrangement in an at least approximately spherical field of view around the camera arrangement, deriving information on solar radiation and / or on the position and / or properties of clouds from the camera data KDH, KDE.

[0253] drawing

[0254] Further advantages will become apparent from the following description of the drawings. The figures illustrate exemplary embodiments of the invention. The figures, the description, and the claims contain numerous features in combination. Those skilled in the art will also expediently consider the features individually and combine them into useful further combinations.

[0255] Examples include:

[0256] Fig. 1 is a schematic representation of an arrangement for detecting and / or predicting at least one parameter for determining and / or predicting at least one component of a global irradiance;

[0257] Fig. 2 is a schematic representation of an arrangement for detecting and / or predicting at least one parameter for determining and / or predicting at least one component of a global irradiance; and Fig. 3 is a schematic representation of a use of an arrangement from Fig. 1 or Fig. 2 and a schematic representation of a method for detecting and / or predicting at least one parameter for determining and / or predicting at least one component of a global irradiance.

[0258] Embodiments of the invention

[0259] In the figures, components of the same type or function similarly are designated by the same reference numerals. The figures are merely examples and are not to be construed as limiting.

[0260] The directional terminology used below, including terms such as "left," "right," "top," "bottom," "before," "behind," "after," and the like, is intended solely to enhance understanding of the figures and is in no way intended to limit the scope of the invention. The components and elements depicted, as well as their design and use, may vary according to the considerations of a person skilled in the art and may be adapted to specific applications.

[0261] Figures 1 and 2 show a schematic representation of an arrangement 100 according to the invention for detecting and / or predicting at least one parameter for determining and / or predicting at least one component of a global irradiance Gl.

[0262] The arrangement 100 comprises at least one evaluation and control device 110 and a camera arrangement 120 with at least one camera 122, 124 and a holding arrangement 126. In the illustrated embodiment, the arrangement 100 comprises a single evaluation and control device 110. In an alternative embodiment not shown, the arrangement 100 can have more than one evaluation and control device 110. In the illustrated embodiment of the arrangement 100, the evaluation and control device 110 is wirelessly connected to the existing cameras 122, 124. A data connection via a cable is also conceivable.

[0263] In this example, the arrangement 100 has a common axis 30 and a horizontal axis 40. The camera arrangement 120 is arranged along the common axis 30. The camera arrangement 120 has a center point 50 arranged on the common axis 30. The common axis 30 is oriented substantially vertically and forms a substantially vertical axis 31 (Figure 1) or is tilted at a tilt angle to the vertical direction and forms an oblique axis 33 (Figure 2).

[0264] In the illustrated embodiment, the arrangement 100 comprises two cameras 122, 124 installed at the same location with opposite orientations. The two cameras 122, 124 are arranged on the common axis 30, essentially vertical axis 31 or oblique axis 33. Thus, the camera 122 and the camera 124 have the common axis 30 as a common axis 30, essentially vertical axis 31 or oblique axis 33. In an alternative embodiment not shown, the arrangement 100 can have more than two cameras 122, 124 at the same location or just one camera 122, 124. The one camera 122, 124 has two sensors (not shown). The sensors are arranged along the common axis 30.The sensors point in opposite directions along the common axis 30, with a first sensor pointing upwards and a second sensor pointing downwards on the common axis 30, which is oriented substantially vertically or obliquely.

[0265] It is understood that the cameras 122 and 124 may be arranged on two axes, rather than along a common axis 30, which axes extend substantially parallel to one another at a short distance, in particular at a distance of at most about 10 m.

[0266] Advantageously, the spatial field of view of at least approximately 360° around the camera arrangement 120 is composed of a spatial first partial field of view and a spatial second partial field of view, each of at least approximately 180° around the camera arrangement 120, which are arranged along the common axis 30. The common axis 30 is in particular oriented substantially in a vertical direction 31 and forms the vertical axis 31, or is oriented at a tilt angle to the vertical direction 31 and forms the oblique axis 33.

[0267] In an exemplary embodiment not shown, the arrangement can have two axes, with one of the cameras 122, 124 being arranged on one axis and the other of the cameras 122, 124 being arranged on the other axis, with the partial fields of view being arranged along the two axes and the two axes being arranged substantially parallel and at a short distance from one another, in particular at a distance of at most approximately 10 m. The holding arrangement 126 fixes the two cameras 122, 124 at a predetermined distance A from an earth's surface 20. In the exemplary embodiment shown, the holding arrangement 126 is L-shaped, but other configurations are also possible. For example, a drone holding the cameras is also conceivable. The holding arrangement fixes the cameras 122, 124 such that the cameras 122, 124 are arranged along the common axis 30.

[0268] The camera arrangement 120 is configured to capture camera data KDH, KDE in a spatial field of view of at least approximately 360° around the camera arrangement 120. The spatial field of view of at least approximately 360° extends along the common, substantially vertical axis 31 or oblique axis 33 and has two fields of view aligned along the common axis 30 and pointing in opposite directions. A first field of view is directed upward, and the second field of view is directed downward along the common axis 30.

[0269] The camera data KDH, KDE are suitable for deriving information on solar radiation and / or the position WP and / or the properties of clouds 12. In the illustrated embodiment, the field of view of the camera arrangement 120 at a given location is composed of an upper partial field of view oriented toward the sky 10 and at least approximately 180° around the camera arrangement and a lower partial field of view oriented toward the earth's surface 20 and at least approximately 180° around the camera arrangement 120. More than two partial fields of view are also conceivable. Furthermore, a different orientation of the partial fields of view is feasible. A field of view of at least approximately 360° around the camera arrangement 120 is understood to mean an at least approximately spherical field of view around a center point 50. The two cameras 122, 124 are arranged at this center point 50.The two cameras 122, 124 are arranged here along the common axis 30, wherein the common axis is aligned substantially vertically and can form a substantially vertical axis, or tilted at a tilt angle to the vertical axis, forming an oblique axis. The center point 50 is formed by the intersection of the common axis 30 and the horizontal axis 40.

[0270] The at least one camera 122, 124 can be understood as an RGB camera or an infrared camera. In the illustrated embodiment of the arrangement 100, the cameras 122, 124 are designed as RGB cameras with fisheye lenses. In an alternative embodiment (not shown), other configurations with parabolic mirrors are also conceivable instead of cameras with fisheye lenses.

[0271] The at least one camera 122, 124 can, for example, capture 24 images per second, which can be provided with a corresponding time stamp. Other image generation rates can also be selected. Additionally, extended setups with, for example, shading devices are conceivable to reduce the disruptive influence of direct sunlight.

[0272] In the illustrated embodiment, the arrangement 100 comprises at least one sky camera 122, which captures camera data KDH in the upper partial field of view associated with the sky, of at least approximately 180° around the camera arrangement 120. Furthermore, in the illustrated embodiment, the arrangement 100 comprises at least one ground camera 124, which captures camera data KDE in the lower partial field of view associated with the earth's surface 20, of at least approximately 180° around the camera arrangement 120. The upper partial field of view and the lower partial field of view extend along the common axis 30.

[0273] In the illustrated embodiment of the arrangement 100, the evaluation and control device 110 determines at least one of the following parameters from the acquired camera data KDH of the upper partial field of view of at least approximately 180° around the camera arrangement:

[0274] (i) direct radiation DNI and / or

[0275] (ii) a diffuse radiation Diffl and / or

[0276] (iii) a global irradiance Gl and / or

[0277] (iv) at least one position WP of cloud features 12 and / or

[0278] (v) areas of the sky covered by clouds 12 and / or

[0279] (vi) from cloud positions WP and / or from the position of cloud features 12 in the camera image between at least two timestamps an angular velocity v p(-x / s of at least one cloud 12 in the camera image.

[0280] Cloud features are image features of the captured images that can be assigned to a cloud 12 and / or a cloud formation.

[0281] In the illustrated embodiment of the arrangement 100, the evaluation and control device 110 determines at least one of the following parameters from the acquired camera data KDE of the lower partial field of view of at least approximately 180° around the camera arrangement: (i) a radiation ERS reflected at the earth's surface 20 and / or

[0282] (ii) an albedo AL of the Earth’s surface of 20 and / or

[0283] (iii) at least one cloud shadow position SP and / or

[0284] (iv) from the cloud shadow positions SP between at least two timestamps a speed v m / s of at least one cloud 12 above the Earth's surface 20.

[0285] In the illustrated embodiment of the arrangement 100, the evaluation and control device 110 determines the radiation from each area of ​​the spatial field of view of at least approximately 360° from intensity values ​​I of the RGB channels in the recorded camera images.

[0286] Based on this, the albedo AL of the ground 20 or a more detailed reflectance of the ground 20 is derived.

[0287] To determine the speeds v m / s , v pix / s The corresponding camera 122, 124 captures image sequences of clouds 12 or cloud shadows 22 at short intervals as camera data KDH, KDE. The shift of image features between the recording times is determined in the image sequences. From this, the movement of a cloud 12 in the sky 10 can be determined. At the same time, the movement of the corresponding cloud shadow 22 on the ground 20 can be determined.

[0288] Due to the known time interval between the recordings, this movement can be converted into a speed v m / s , the cloud 12 above the Earth's surface 20 and into an angular velocity, v pix / s of the clouds 12 in the camera image. In the illustrated embodiment of the arrangement 100, the at least one evaluation and control device 110 determines from the speed v m / s of at least one cloud 12 above the Earth's surface 20 and the angular velocity v pix / s of at least one cloud 12 in the camera image a height H1 , H2 of the clouds 12.

[0289] H1 corresponds to the distance between cloud 12 and the ground opposite it 20.

[0290] H2 corresponds to the distance between the upwardly directed camera 122 and a height of the cloud 12 projected over the upwardly directed camera 122. H2 can be calculated from the speed of the clouds v m / , can be determined. H1 can be determined from the known distance A of the camera 122, 124 to the ground 20 and a known elevation profile of the area to be monitored.

[0291] The evaluation and control device 110 determines with the height H1 , H2 of the clouds 12 and the cloud speed v m / s above the earth's surface 20 a future cloud position WP and from this a future shading or a future global irradiance Gl of a given horizontal or inclined area.

[0292] In the illustrated embodiment, at least one evaluation and control device 110 extrapolates the speed v m / s of clouds 12 above the Earth's surface 20 and the angular velocity v pix / s of clouds 12 in the camera image temporally and spatially. In an alternative, not shown embodiment, only speeds v m / s , v Pix / s of the clouds 12 whose cloud shadows 22 are captured by the lower partial field of view of at least approximately 180° around the camera arrangement. In the illustrated embodiment of the arrangement 100, the at least one evaluation and control device 110 determines at least one current and / or future value of at least one component of the global irradiance Gl from the camera data KDH, KDE and / or the determined parameters in a spectrally and / or angularly resolved manner.

[0293] In the illustrated embodiment of the arrangement 100, at least one evaluation and control device 110 determines the at least one component of the global irradiance Gl on an inclined surface.

[0294] Figure 3 shows a schematic representation of a use of an arrangement from Figure 1 or Figure 2 and a schematic representation of a method 200 for detecting and / or predicting at least one parameter for determining and / or predicting at least one component of a global irradiance Eq.

[0295] In method steps S212 and S214, camera data KDH, KDE are acquired at a common location in a spatial field of view of at least approximately 360° around a camera arrangement 120. Information on solar radiation and / or position WP and / or properties of clouds 12 are derived from the camera data KDH, KDE.

[0296] In the described exemplary embodiment, the spatial field of view of at least approximately 360° around the camera arrangement is composed of an upper partial field of view of at least approximately 180° around the camera arrangement 120, oriented towards the sky 10, and a lower partial field of view of at least approximately 180° around the camera arrangement 120, oriented towards the earth's surface 20. In method step S212, at least one sky camera 122 acquires camera data KDH in an upper partial field of view of at least approximately 180° around the camera arrangement, associated with the sky 10. In method step S214, at least one ground camera 124 acquires camera data KDE in a lower partial field of view of at least approximately 180° around the camera arrangement, associated with the earth's surface 20. Method steps S212 and S214 can be executed simultaneously or at different times.In an alternative method step, camera data KDE, KDH can first be assigned to the earth's surface and the sky 10. This step is omitted in the illustrated embodiment because the upper field of view and the lower field of view enable a clear assignment of the camera data.

[0297] In process step S222, KDH of the upper field of view of at least approximately 180° around the camera arrangement is determined from the acquired camera data:

[0298] (i) direct radiation DNI and / or

[0299] (ii) a diffuse radiation Diffl and / or

[0300] (iii) a global irradiance Gl and / or

[0301] (iv) areas of the sky covered by clouds and / or

[0302] (v) at least one cloud position WP and / or

[0303] (vi) from cloud positions WP and / or from the position of two timestamps an angular velocity v pix / sClouds 12 in the camera image.

[0304] In process step S224, the acquired camera data KDE of the lower field of view of at least approximately 180° around the camera arrangement are used:

[0305] (i) a radiation ERS reflected at the Earth’s surface 20 and / or

[0306] (ii) an albedo AL of the Earth’s surface 20 and / or (iii) at least one cloud shadow position SP and / or

[0307] (iv) from the cloud shadow positions SP between at least two timestamps a speed v m / s of at least one cloud 12 above the earth's surface 20.

[0308] To determine the direct radiation DNI and / or the diffuse radiation Diffl and / or a radiation ERS reflected at the earth's surface 20, intensity values ​​I of at least one color channel of the corresponding camera 122, 124 are evaluated.

[0309] In method step S230, the global irradiance Gl is calculated from the components Diffl, DNI, ERS of the global irradiance Gl determined in method steps S222 and S224. At least one component Diffl, DNI, ERS of the global irradiance Gl can also be determined on an inclined surface inclined to the Earth's surface 20.

[0310] In process step S230, the speed v m / , of at least one cloud 12 above the Earth's surface 20 and the angular velocity v pix / s of at least one cloud 12 in the camera image a height H1, H2 of the clouds 12 is determined.

[0311] Here, the speed v m / s of clouds 12 above the Earth's surface 20 and the angular velocity v pix / s of clouds 12 in the camera image can be extrapolated temporally and spatially.

[0312] In process step S240, the height H1 , H2 of the clouds 12 and the cloud speed v m / s above the earth's surface 20 a future cloud position WP is determined and from this a future shading and / or the future global irradiance Gl of a given area is determined as a forecast. The current and / or future values ​​of the components Diffl, DNI, ERS of the global irradiance Gl determined in method steps S222 and S224 can be determined from the camera data KDH, KDE and / or the determined parameters at least spectrally and / or angularly resolved.

[0313] The method 200 is executed in a computer program that includes instructions that cause a device 100 to be executed for determining at least one parameter for determining at least one component of a global irradiance Gl. The computer program can be part of a computer program product.

[0314] The computer program or computer program product comprises instructions which, when the computer program is executed by a computer, cause the method 200 for determining at least one parameter for determining at least one component of a global irradiance Gl to be carried out, wherein the following steps are carried out:

[0315] - capturing camera data KDH, KDE from a camera arrangement 120 in a spherical field of view around the camera arrangement 120,

[0316] - Deriving information on solar radiation and / or position (WP) and / or properties of clouds 12 from the camera data KDH, KDE.

[0317] Reference symbol

[0318] 10 Heavens

[0319] 12 Cloud

[0320] 20 Earth's surface

[0321] 22 Shadow of the Cloud

[0322] 30 common axis

[0323] 31 vertical direction, vertical axis

[0324] 33 oblique axis

[0325] 40 horizontal axis

[0326] 50 Center of the camera arrangement

[0327] 100 arrangement

[0328] 110 Evaluation and control device

[0329] 120 Camera arrangement

[0330] 122 Sky Camera

[0331] 124 ground camera

[0332] 126 Holding arrangement

[0333] 200 procedures

[0334] S212-S240 Process steps

[0335] KDH, KDE camera data

[0336] WP Position of the cloud

[0337] SP Position Cloud Shadow v P ix / s angular velocity v m / s Speed ​​above the ground

[0338] I Intensity of a color channel

[0339] H1 Height of the cloud from the Earth's surface

[0340] H2 Height of the cloud from the highest point of the camera array

[0341] A Distance of the camera arrangement to the earth's surface

[0342] Gl Global irradiance

[0343] Diff I diffuse radiation

[0344] DNI direct radiation

[0345] ERS radiation reflected at the Earth's surface

Claims

Patent claims 1. Arrangement (100) for determining at least one parameter for determining at least one component of a global irradiance Gl, which comprises an evaluation and control device (110) and a camera arrangement (120) with at least one camera (122, 124), wherein the at least one camera (122, 124) is fixed at a predetermined distance (A) from an earth's surface (20) at least during the determination of the parameter, wherein the camera arrangement (120) is designed to capture camera data KDH, KDE in a spatial field of view of at least approximately 360° around the camera arrangement (120), wherein the camera data KDH, KDE are suitable for deriving information on solar radiation and / or on the position (WP) and / or on the properties of clouds (12).

2. Arrangement according to claim 1, wherein at least one first camera (122) acquires camera data in a first partial field of view and at least one second camera (124) acquires camera data in a second partial field of view, wherein the two partial fields of view of the cameras (122, 124) complement each other to form a field of view of at least approximately 360°, in particular wherein at least the first camera (122) as a sky camera (123) acquires camera data KDH in the first partial field of view, which is oriented towards the sky (10) and forms an upper partial field of view, and the at least second camera (124) as a ground camera (125) acquires camera data KDE in the second partial field of view, which is oriented towards the earth's surface (20) and forms a lower partial field of view, in particular wherein the cameras (122, 124) are each designed as a fisheye camera, or wherein a 360° camera with a spatial field of view of at least approximately 360° around the camera arrangement (120) captures camera data KDH in a first partial field of view and captures camera data KDE in a second partial field of view, in particular wherein the first partial field of view forms an upper partial field of view oriented towards the sky (10) and the second partial field of view forms a lower partial field of view oriented towards the earth's surface (20).Arrangement according to claim 1 or 2, wherein the field of view of at least approximately 360° around the camera arrangement (120) is composed of the spatial first partial field of view and the spatial second partial field of view, each of at least approximately 180° around the camera arrangement (120), wherein the partial fields of view are arranged one above the other, in particular wherein the partial fields of view are arranged along at least one axis (30) or along two axes that are arranged one above the other approximately parallel and at a short distance from one another, wherein the at least one axis (30) is aligned substantially in a vertical direction (31), or in particular wherein the partial fields of view are arranged along at least one axis (30) or along two axes that are arranged one above the other approximately parallel and at a short distance from one another, wherein the at least one axis (30) is aligned at a tilt angle to a vertical direction (31).Arrangement according to one of the preceding claims, wherein the evaluation and control device (110) takes camera data KDH assigned to the sky (10) from the recorded camera data KDH, KDE and determines at least one of the following parameters from this camera data KDH assigned to the sky (10):. (i) direct radiation DNI and / or (ii) a diffuse radiation Diffl and / or (iii) a global irradiance Gl and / or (iv) at least one position of cloud features and / or (v) areas of the sky covered by clouds and / or (vi) from cloud positions WP and / or from the position of cloud features in the camera image between at least two timestamps an angular velocity v pix / sof at least one cloud (12) in the camera image. Arrangement according to one of the preceding claims, wherein the evaluation and control device (110) extracts camera data KDE associated with the earth's surface (20) from the acquired camera data KDH, KDE, and determines at least one of the following parameters from these camera data KDE associated with the earth's surface (20): (i) a radiation ERS reflected at the earth’s surface (20) and / or (ii) an albedo AL of the Earth’s surface (20) and / or (iii) at least one cloud shadow position SP and / or (iv) from the cloud shadow positions SP between at least two timestamps a speed v m / s of at least one cloud (12) above the earth's surface (20). Arrangement according to one of claims 4 or 5, wherein the evaluation and control device (110) determines the speed v m / s of at least one cloud (12) above the earth's surface (20) and the angular velocity v plx / sof at least one cloud (12) in the camera image, a height (H1, H2) of the clouds (12) is determined, in particular wherein the at least one evaluation and control device (110) is provided with the height (H1, H2) of the clouds and the cloud speed v m / s above the earth's surface (20) a future cloud position WP is determined and from this a future shading or a future global irradiance Gl of a given area is determined.

7. Arrangement according to one of claims 4 to 6, wherein the at least one evaluation and control device (110) determines the speed v m / s of clouds (12) above the Earth's surface (20) and / or the angular velocity v pix / s of clouds (12) in the camera image extrapolated temporally and spatially.

8. Arrangement according to one of claims 4 to 7, wherein the at least one evaluation and control device (110) determines at least one current and / or future value of at least one component of the global irradiance Gl from the camera data KDH, KDE and / or the determined parameters in a spectrally and / or angularly resolved manner.

9. Arrangement according to claim 8, wherein at least one evaluation and control device (110) determines the at least one component of the global irradiance Gl on an inclined, in particular arbitrarily oriented, surface.

10. Use of an arrangement (100) according to one of the preceding claims for determining at least one parameter for determining at least one component of a global irradiance Gl, wherein camera data KDH, KDE are recorded in a spatial field of view of at least approximately 360° around the camera arrangement (120), wherein information on solar radiation and / or on the position and / or on properties of clouds is derived from the camera data KDH, KDE.

11. Use according to claim 10, wherein camera data are acquired in a first partial field of view with at least one first camera (122) and camera data are acquired in a second partial field of view with at least one second camera (124), wherein the two partial fields of view of the cameras (122, 124) complement each other to form a field of view of at least approximately 360°, in particular wherein at least one first camera (122) as a sky camera (123) acquires camera data KDH in the first partial field of view, which is oriented towards the sky (10) and forms an upper partial field of view, and at least one second camera (124) as a ground camera (125) acquires camera data KDE in the second partial field of view, which is oriented towards the earth's surface (20) and forms a lower partial field of view,or wherein, with a 360° camera having a spatial field of view of at least approximately 360° around the camera arrangement (120), camera data KDH are captured in a first partial field of view and camera data KDE are captured in a second partial field of view, in particular wherein the first partial field of view forms an upper partial field of view oriented towards the sky (10) and the second partial field of view forms a lower partial field of view oriented towards the earth's surface (20).

12. Use according to claim 10 or 11, wherein the field of view of at least approximately 360° around the camera arrangement (120) is composed of the spatial first partial field of view and the spatial second partial field of view of at least approximately 180° around the camera arrangement (120), wherein the partial fields of view are arranged one above the other, In particular, the partial fields of view are arranged along at least one axis (30) or along two axes that are arranged approximately parallel and closely spaced from one another, one above the other, wherein the at least one axis (30) is aligned substantially in a vertical direction (31), or in particular, the partial fields of view are arranged along at least one axis (30) or along two axes that are arranged approximately parallel and closely spaced from one another, one above the other, wherein the at least one axis (30) is aligned at a tilt angle to a vertical direction (31). Use according to one of claims 10 to 12, wherein camera data KDH associated with the sky (10) is extracted from the acquired camera data KDH, KDE, and at least one of the following parameters is extracted from these camera data KDH associated with the sky (10): (i) direct radiation DNI and / or (ii) a diffuse radiation Diffl and / or (iii) a global irradiance Gl and / or (iv) at least one position of cloud features and / or (v) areas of the sky covered by clouds and / or (vi) from cloud positions WP and / or from the position of cloud features in the camera image between at least two timestamps an angular velocity v pix / s of at least one cloud (12) in the camera image is determined. Use according to one of claims 10 to 13, wherein camera data KDE associated with the earth's surface (20) are taken from the acquired camera data KDH, KDE, and at least one of the following parameters is determined from these camera data KDE associated with the earth's surface (20) (i) a radiation ERS reflected at the earth’s surface (20) and / or (ii) an albedo AL of the Earth’s surface (20) and / or (iii) at least one cloud shadow position SP and / or (iv) from the cloud shadow positions SP between at least two timestamps a speed v m / s of at least one cloud (12) above the earth's surface (20).

15. Use according to claim 14, wherein the speed v m / s of at least one cloud (12) above the earth's surface (20) and the angular velocity v pix / s of at least one cloud (12) in the camera image, a height (H1, H2) of the clouds (12) is determined, in particular with the height (H1, H2) of the clouds and the cloud speed v m / s a future cloud position WP is determined above the earth's surface (20) and from this a future shading and / or the future global irradiance Gl of a given area is determined.

16. Use according to one of claims 14 or 15, wherein the speed v m / s of clouds (12) above the Earth's surface (20) and / or the angular velocity v pix / sof clouds (12) in the camera image can be extrapolated temporally and spatially.

17. Use according to one of claims 10 to 16, wherein at least one current and / or future value of at least one component of the global irradiance Gl is determined spectrally and / or angularly resolved from the camera data KDH, KDE and / or the determined parameters.

18. Use according to claim 17, wherein the at least one component of the global irradiance Gl is determined on an inclined, in particular arbitrarily oriented, surface. Method (200), in particular a computer-implemented method, for determining at least one parameter for determining at least one component of a global irradiance Gl, wherein camera data KDH, KDE are acquired at a common location in a spatial field of view of at least approximately 360° around a camera arrangement 120, wherein information on solar radiation and / or on the position (WP) and / or properties of clouds (12) is derived from the camera data KDH, KDE. Method according to claim 19, wherein camera data in a first partial field of view is acquired with at least one first camera (122) and camera data in a second partial field of view is acquired with at least one second camera (124), wherein the two partial fields of view of the cameras (122, 124) complement each other to form a field of view of at least approximately 360°, in particular wherein camera data KDH in the first partial field of view is acquired with at least one first camera (122) as a sky camera (123).which in this case is oriented towards the sky (10) and forms an upper partial field of view, and with at least one second camera (124) as a ground camera (125), camera data KDE are acquired in the second partial field of view, which in this case is oriented towards the earth's surface (20) and forms a lower partial field of view, or wherein with a 360° camera with a field of view of at least approximately 360° around the camera arrangement (120), camera data KDH are acquired in a first partial field of view and camera data KDE are acquired in a second partial field of view, in particular wherein the first partial field of view forms an upper partial field of view oriented towards the sky (10) and the second partial field of view forms a lower partial field of view oriented towards the earth's surface (20). Method according to claim 19 or 20, wherein the field of view of at least approximately 360° around the camera arrangement (120) is composed of the spatial first partial field of view and the spatial second partial field of view, each of at least approximately 180° around the camera arrangement (120), wherein the partial fields of view are arranged one above the other, in particular wherein the partial fields of view are arranged along at least one axis (30) or along two axes which are arranged one above the other approximately parallel and at a short distance from one another, wherein the at least one axis (30) is aligned substantially in a vertical direction (31), or in particular wherein the partial fields of view are arranged along at least one axis (30) or along two axes which are arranged one above the other approximately parallel and at a short distance from one another, wherein the at least one axis (30) is aligned at a tilt angle to a vertical direction (31).Method according to one of claims 19 to 21, wherein camera data KDH assigned to the sky (10) are taken from the acquired camera data KDH, KDE and at least one of the following parameters is taken from these camera data KDH assigned to the sky (10). (i) direct radiation DNI and / or (ii) a diffuse radiation Diffl and / or (iii) a global irradiance Gl and / or (iv) areas of the sky covered by clouds and / or (v) at least one cloud position WP and / or (vi) from cloud positions WP and / or from the position of cloud features in the camera image between at least two timestamps an angular velocity v pix / s of at least one cloud (12) in the camera image.

23. Method according to one of claims 19 to 22, wherein camera data KDH associated with the earth's surface (20) is taken from the acquired camera data KDH, KDE, and at least one of the following parameters is taken from these camera data KDH associated with the earth's surface (20): (i) a radiation ERS reflected at the earth’s surface (20) and / or (ii) an albedo AL of the Earth’s surface (20) and / or (iii) at least one cloud shadow position SP and / or (iv) from the cloud shadow positions SP between at least two timestamps a speed v m / s of at least one cloud (12) above the earth's surface (20).

24. Method according to claim 23, wherein the speed v m / s of at least one cloud (12) above the earth's surface (20) and the angular velocity v pix / sof at least one cloud (12) in the camera image, a height (H1, H2) of the clouds (12) is determined, in particular with the height (H1, H2) of the clouds (12) and the cloud speed v m / s a future cloud position WP is determined above the earth's surface (20) and from this a future shading and / or the future global irradiance Gl of a given area is determined.

25. Method according to one of claims 23 to 24, wherein the speed v m / s of clouds (12) above the Earth's surface (20) and / or the angular velocity v pix / s of clouds (12) in the camera image can be extrapolated temporally and spatially.

26. Method according to one of claims 19 to 25, wherein at least one current and / or future value of at least one component of the global irradiance Gl is determined spectrally and / or angularly resolved from the camera data KDH, KDE and / or the determined parameters. Method according to claim 26, wherein the at least one component of the global irradiance Gl is determined on an inclined, in particular arbitrarily oriented, surface. Computer program or computer program product, comprising instructions that cause an arrangement (100) according to one of claims 1-9 to carry out a method (200) for determining at least one parameter for determining at least one component of a global irradiance Gl according to one of claims 19 to 27. Computer program or computer program product, comprising instructions that, when the computer program is executed by a computer, cause the computer to carry out a method (200) for determining at least one parameter for determining at least one component of a global irradiance Gl according to one of claims 19 to 27, comprising Acquiring camera data KDH, KDE from a camera arrangement (120) in a spherical field of view around the camera arrangement 120, Deriving information on solar radiation and / or position (WP) and / or properties of clouds (12) from the camera data KDH, KDE.

Images