CN118463843A - Heliostat surface shape detection system and method - Google Patents
Heliostat surface shape detection system and method Download PDFInfo
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Abstract
The invention provides a heliostat surface shape detection system and a heliostat surface shape detection method, wherein the method comprises the following steps: controlling the center of a reflection light spot of a target heliostat to an acquisition port of a heliostat image acquisition device; collecting a sun image and a heliostat image of the sun reflected by a target heliostat through an acquisition device; constructing a theoretical image simulating the sun in the target heliostat according to the sun image, the attitude information of the target heliostat and the attitude information of the heliostat image acquisition device; comparing the theoretical image with the heliostat image to obtain a surface shape detection result of the target heliostat; the heliostat image acquisition device is arranged on the heat absorption tower, so that the normal operation of the heliostat is not affected when the target heliostat is detected, in addition, the surface shape detection result of the target heliostat is obtained by processing the sun image and the image reflected by the heliostat, and the detection efficiency and the accuracy are high; meanwhile, the surface shape conditions of the target heliostat under multiple postures can be detected without being influenced by external factors, and the applicability is high.
Description
Technical Field
The invention belongs to the technical field of power generation, and particularly relates to a heliostat surface shape detection system and method.
Background
The heliostat accounts for about 50% of the cost of the power station in the power station, is used for automatically tracking the sun, and is used for reflecting and converging solar radiation to the heat absorber with high precision, so that efficient photo-thermal conversion of the power station is realized, and the mirror surface shape of the heliostat is detected with high precision, so that the sunlight converged by the heliostat can be guaranteed to accurately reflect to reach the heat absorber.
However, during the production, processing, transportation, installation, operation and the like of the heliostat, the actual surface shape of the heliostat has a large deviation from the theoretical design value: on one hand, certain deviation exists between the actual integral surface shape formed by splicing the unit mirrors and the theoretical design surface shape in the installation process of the heliostat; on the other hand, the heliostat mirror surface is deformed in the running process under the influence of factors such as wind load, self gravity, temperature transformation and the like, so that the heliostat mirror surface cannot form an ideal design curved surface. The factors cause the small deviation of the surface shape of the heliostat to lead the reflected solar radiation to deviate from the lighting opening of the heat absorber, thereby reducing the condensation efficiency of the mirror field and the income of a power station, and even affecting the operation safety of the heat absorber and the tower. Therefore, the rapid heliostat mirror surface shape detection is a key for improving the condensation efficiency of a mirror field and the operation efficiency of a power station.
The detection method adopted in the prior art is greatly influenced by the external environment, and the normal operation of the geodetic sperm is influenced in the detection process.
Disclosure of Invention
Accordingly, the present invention is directed to a heliostat surface shape detection system and method for improving detection applicability, detection accuracy and efficiency.
The application discloses a heliostat surface shape detection method, which comprises the following steps:
When the surface shape detection of the heliostat is required, controlling the center of a reflection light spot of the target heliostat to an acquisition port of the heliostat image acquisition device; the heliostat image acquisition device is arranged on the heat absorption tower;
collecting a sun image through a sun image acquisition device, and collecting a heliostat image of the sun reflected by the target heliostat through the heliostat image acquisition device;
constructing a theoretical image of the simulated sun in the target heliostat according to the sun image, the attitude information of the target heliostat and the attitude information of the heliostat image acquisition device; the gesture information includes: azimuth and pitch;
and comparing the theoretical image with the heliostat image to obtain a surface shape detection result of the target heliostat.
Optionally, the theoretical image simulating the sun in the target heliostat is constructed according to the sun image, the attitude information of the target heliostat and the attitude information of the heliostat image acquisition device; the posture information includes: azimuth and pitch angles, including:
Fitting the brightness distribution of the solar image to obtain a solar brightness distribution function;
Acquiring attitude information of the target heliostat when the center of the reflection light spot is adjusted to the acquisition port of the heliostat image acquisition device;
Confirming azimuth/altitude angle of the sun;
And simulating an image of the sun reflected by the target heliostat by combining the structural size of the target heliostat, the theoretical design surface shape, the attitude information of the target heliostat, the azimuth angle/altitude angle of the sun and the solar brightness distribution function to obtain the theoretical image.
Optionally, the comparing the theoretical image with the heliostat image to obtain a surface shape detection result of the target heliostat includes:
squaring the inverse function of the heliostat image to obtain the inverse function of the heliostat image;
Determining a partial derivative of the wavefront error of the target heliostat according to the inverse function of the heliostat image;
Determining the optical aberration of the theoretical image, removing the optical aberration from the partial derivative and performing matrix transformation to obtain a surface slope error;
Reconstructing the surface shape error of the target heliostat according to the surface slope error, and obtaining the actual surface shape of the target heliostat according to the surface shape error and the reference optical surface corresponding to the theoretical image.
Optionally, before the collecting the sun image by the sun image obtaining device and collecting the heliostat image of the sun reflected by the heliostat image obtaining device, the method further includes:
and controlling the solar image acquisition device to automatically track the sun and acquire a solar image.
Optionally, the controlling the solar image obtaining device to automatically track the sun includes:
Controlling an automatic tracking device in the solar image acquisition device to automatically track the sun; and controlling a solar industrial camera arranged on the automatic tracking device in the solar image acquisition device to acquire a solar image.
Optionally, the center of the reflection light spot of the target heliostat is controlled to the acquisition port of the heliostat image acquisition device; the heliostat image acquisition device is installed before on the heat absorption tower, still includes:
acquiring the working state of each heliostat in a heliostat field;
and determining a target heliostat needing to detect the surface shape according to the working state of each heliostat.
The second aspect of the application discloses a heliostat surface detection system comprising: a solar image acquisition device, a heliostat image acquisition device, a control device and a processing device;
The solar image acquisition device is used for acquiring a solar image;
the heliostat image acquisition device is arranged on the heat absorption tower;
The processing device is respectively connected with the heliostat, the solar image acquisition device and the heliostat image acquisition device through the control device;
The processing device is combined with the control device to realize the heliostat surface detection method according to any one of the first aspect of the application.
Optionally, the solar image acquisition device includes: an automatic tracking device and a solar industrial camera mounted on the automatic tracking device;
the automatic tracking device is used for automatically tracking the sun;
the solar industrial camera is used for collecting solar images.
Optionally, the heliostat image acquisition device includes: the device comprises a protection structure, a cradle head and a heliostat industrial camera arranged on the cradle head;
The cradle head and the heliostat industrial camera are both arranged on the protection structure;
The cradle head is used for carrying out horizontal/pitching double-shaft adjustment and displaying azimuth angle and pitch angle;
the heliostat industrial camera is used for collecting heliostat images reflected by the heliostats.
Optionally, the number of heliostat industrial cameras in the heliostat image acquisition device is 1 or more.
According to the technical scheme, when the surface shape detection of the heliostat is required, the reflection light spot center of the target heliostat is controlled to the acquisition port of the heliostat image acquisition device; collecting a sun image through a sun image acquisition device, and collecting a heliostat image of the sun reflected by a target heliostat through a heliostat image acquisition device; constructing a theoretical image simulating the sun in the target heliostat according to the sun image, the attitude information of the target heliostat and the attitude information of the heliostat image acquisition device; the posture information includes: azimuth and pitch; comparing the theoretical image with the heliostat image to obtain a surface shape detection result of the target heliostat; the heliostat image acquisition device is arranged on the heat absorption tower, so that the normal operation of the target heliostat is not influenced when the surface shape detection is carried out on the target heliostat, the heliostat can still reflect light spots to the heat absorption tower, in addition, the surface shape detection result of the target heliostat is obtained by processing a sun image and an image reflected by the heliostat, and the detection efficiency and the accuracy are high; meanwhile, the method is not influenced by external factors, can detect the surface shape conditions of the target heliostat under multiple postures, and is a quick, simple and efficient detection method and high in applicability.
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In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a flow chart of a heliostat surface detection method provided by an embodiment of the invention;
FIG. 2 is a schematic diagram of a heliostat surface detection system according to an embodiment of the invention;
FIG. 3 is a schematic diagram of a solar image acquisition device in a heliostat surface detection system according to an embodiment of the invention;
Fig. 4 is a schematic diagram of a heliostat image acquisition device in a heliostat surface detection system according to an embodiment of the invention.
Detailed Description
For the purpose of making the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are some embodiments of the present invention, but not all embodiments of the present invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
In the present disclosure, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.
In the prior art, a stripe projection device mounted on a cradle head is carried by an unmanned aerial vehicle, the unmanned aerial vehicle flies above a measured heliostat according to a specific flight track, stripes are projected to each area of the heliostat mirror, an industrial camera synchronously shoots stripe images reflected by each area of the heliostat mirror, the stripe images reflected by the heliostat mirror shot by the industrial camera are transmitted to an image and data processing device, and the synthesis of the stripe images reflected by the mirror surface of the whole heliostat mirror and the calculation of mirror surface type errors are completed. The technology is applied to heliostat surface shape detection of a heliostat field, and because stripes are required to be projected to each area of the heliostat surface to collect reflected stripe images for analysis and processing, the detection process is low in efficiency, and the detection process can be time-consuming when the heliostat area is large; in the detection process, the heliostat to be detected is required to be adjusted to a specific posture to finish detection, and the normal operation of the heliostat is affected; the wind speed of the tower-type power station in China is high, the wind influence of the unmanned aerial vehicle carried with the projection device is high, and the quality of the acquired image of the unmanned aerial vehicle can be greatly changed.
The other prior art also provides a high-precision heliostat surface shape quick calculation system which aims at the characteristic of high requirement on the heliostat surface shape reflection pointing precision, and based on the straight stripe pattern reflected by the heliostat surface shape, utilizes a calculation algorithm of geometric relations to represent the opposite surface shape of the heliostat surface by the reflection normal deviation angle distribution of the heliostat surface in two orthogonal directions. The whole measuring process utilizes a projector to project a stripe image, and a camera collects the deformed stripe image reflected by the heliostat and performs image processing to obtain heliostat surface shape information. The measuring process is carried out in night or darkroom due to the fact that the projector is used for projecting the orthogonal stripes, and certain requirements are met for the detection environment; in addition, the heliostat to be measured needs to maintain a specific posture to reflect the orthogonal stripe image, so that the normal operation of the heliostat is affected; because the diffuse reflection plate is used for presenting the orthogonal stripe image projected by the projector, the area of the diffuse reflection plate corresponding to the heliostat is very large (possibly hundreds of square meters) when the area of the heliostat is large (from 1 square meter to 180 square meters), the application possibility of the diffuse reflection plate with the large area in an actual power station is low, and meanwhile, the flatness and stability of the diffuse reflection plate with the large area have great influence on the detection result.
The embodiment of the application provides a heliostat surface shape detection method, which is used for solving the problems that the detection method adopted in the prior art is greatly influenced by external environment and the normal operation of the heliostat is influenced in the detection process.
Referring to fig. 1, the heliostat profile detection method includes:
S101, when the surface shape detection of the heliostat is needed, controlling the center of a reflection light spot of the target heliostat to an acquisition port of the heliostat image acquisition device.
The heliostat image acquisition device is arranged on the heat absorption tower. That is, the reflection light spot center of the target heliostat after adjustment is positioned on the heat absorption tower, and the heat absorption tower can absorb the energy reflected by the heliostat so as to generate power and the like, so that the normal operation of the target heliostat is not affected.
The heliostat mainly comprises a reflecting mirror and a bracket, the heliostat converges and reflects solar radiation energy to a target position, and the target position presents light spots reflected by the heliostat.
The power station includes a heliostat field and an endothermic tower, the heliostat field includes a plurality of heliostats, the heliostat to be detected in the heliostat field may be a target heliostat, and the target heliostat may be a plurality of heliostats or one heliostat, which is not specifically limited herein, and may be within the scope of the application according to actual conditions.
Specifically, the heliostat image acquisition device comprises: cradle head, heliostat industrial camera, and protective structure, etc., the image acquisition port of the heliostat industrial camera is used as the acquisition port of the heliostat image acquisition device, i.e. the center of the reflection light spot of the target heliostat is adjusted to the image acquisition port of the heliostat industrial camera in the heliostat image acquisition device.
S102, collecting a sun image through a sun image acquisition device, and collecting a heliostat image of the sun reflected by a target heliostat through a heliostat image acquisition device.
Specifically, the solar image acquisition device can track the sun and acquire solar images, more specifically, the solar image acquisition device receives a tracking acquisition instruction to the solar image acquisition device to track the sun and acquire the solar images, so that the solar images can be acquired through the solar image acquisition device.
The heliostat image acquisition device can acquire heliostat images reflected by the target heliostat, wherein the heliostat images are images of the target heliostat reflecting the sun. For example, the sun impinges on a target heliostat that is reflected to a heliostat image acquisition device.
That is, the heliostat image is also a sun image, except that the heliostat image is a sun image reflected by the target heliostat. The sun image acquired by the sun image acquisition device is an image for directly acquiring the sun. For convenience of explanation, the sun images referred to below are all sun images collected by the sun image obtaining device, and the heliostat images are images collected by the heliostat image obtaining device.
The azimuth angle and the pitching angle of the heliostat image acquisition device can be controlled to rotate, so that the whole image of the target heliostat can be acquired, namely, the complete heliostat image is acquired.
S103, constructing a theoretical image of the simulated sun in the target heliostat according to the sun image, the attitude information of the target heliostat and the attitude information of the heliostat image acquisition device.
The posture information includes: azimuth and pitch; of course, the gesture information may include other information, which is not described herein in detail, and may be determined according to actual situations, which are all within the protection scope of the present application.
The theoretical image is a virtual solar image in the target heliostat, which is obtained by constructing according to the combination of the solar image and the information of the target heliostat and the information system of the corresponding acquisition device, namely an image of the collected sun reflected by the target heliostat is simulated.
S104, comparing the theoretical image with the heliostat image to obtain a surface shape detection result of the target heliostat.
From the above description, the theoretical image is a simulated image, i.e. an image without reference to the optical surface in an ideal state. The reference optical surface is an ideal planar or spherical mirror with a focal length equal to the distance D from the target heliostat to the target plane.
The heliostat image is an image actually reflected by the target heliostat, so that the theoretical image and the actual image can be compared to obtain the surface shape detection result of the target heliostat.
Specifically, an error value can be obtained by comparing the theoretical image with the heliostat image, and then a surface shape detection result of the target heliostat can be obtained according to the error value.
The surface shape information of the target heliostat under multiple postures can be determined, and the application range is wide.
In this embodiment, when the surface shape detection of the heliostat is required, the center of the reflection light spot of the target heliostat is controlled to the acquisition port of the heliostat image acquisition device; collecting a sun image through a sun image acquisition device, and collecting a heliostat image of the sun reflected by a target heliostat through a heliostat image acquisition device; constructing a theoretical image simulating the sun in the target heliostat according to the sun image, the attitude information of the target heliostat and the attitude information of the heliostat image acquisition device; the posture information includes: azimuth and pitch; comparing the theoretical image with the heliostat image to obtain a surface shape detection result of the target heliostat; the heliostat image acquisition device is arranged on the heat absorption tower, so that the normal operation of the target heliostat is not influenced when the surface shape detection is carried out on the target heliostat, the heliostat can still reflect light spots to the heat absorption tower, in addition, the surface shape detection result of the target heliostat is obtained by processing a sun image and an image reflected by the heliostat, and the detection efficiency and the accuracy are high; meanwhile, the method is not influenced by external factors, can detect the surface shape conditions of the target heliostat under multiple postures, and is a quick, simple and efficient detection method.
Optionally, step S103, constructing a theoretical image simulating the sun in the target heliostat according to the sun image, the heliostat image, the attitude information of the target heliostat, and the attitude information of the heliostat image acquisition device; the posture information includes: azimuth and pitch angles, including:
firstly, fitting the brightness distribution of the solar image to obtain a solar brightness distribution function.
Specifically, a plurality of solar images can be collected, and the brightness distribution of the plurality of solar images is fitted to obtain a fitted solar brightness distribution function.
The solar brightness distribution function may be to determine the brightness distribution of the sun in the solar image, thereby providing for the subsequent construction of a virtual theoretical image.
And secondly, acquiring attitude information when the target heliostat is positioned at the center of the reflection light spot and adjusted to the acquisition port of the heliostat image acquisition device.
That is, the target heliostat is controlled to be positioned at the center of the reflection light spot and adjusted to the acquisition port of the heliostat image acquisition device, and then the current posture information of the target heliostat is acquired.
The posture information includes: azimuth and pitch. The posture information may also be time information matching, specifically, corresponding time information may be added to the posture information, for example, the time under the posture information, and the time information may be specific date and time information, for example, posture information under xx, month and xx days.
Next, the azimuth/altitude angle of the sun is confirmed.
Specifically, the azimuth angle and the altitude angle of the sun may be determined according to the date and time.
The altitude of the sun refers to the angle between the sun's rays and the horizon, and is used to represent the altitude of the sun in the sky. The azimuth angle of the sun refers to the angle from a certain point toward the sun, and is used to represent the position of the sun in the sky.
Generally, the azimuth angle and the altitude angle of the sun are different at different dates and times in the same place, so that the relationship between the date and time and the altitude angle of the sun and the azimuth angle of the sun can be constructed in advance, and the azimuth angle and the altitude angle of the sun corresponding to the date and time can be determined according to the date and time.
Of course, the azimuth angle and the altitude angle of the sun can also be obtained through detection and calculation, and the specific detection and calculation process is not particularly limited herein, and can be determined according to practical situations, and the detection and calculation process is within the protection scope of the application.
And finally, simulating an image of the sun reflected by the target heliostat by combining the structural size of the target heliostat, the theoretical design surface shape, the attitude information of the target heliostat, the azimuth angle/altitude angle of the sun and the solar brightness distribution function, and obtaining a theoretical image.
Specifically, the structural dimensions of the target heliostat may be divided into a structure and a dimension, for example, the structure may be circular, square, and the like, and the dimension is the size of the target heliostat.
The theoretical design surface shape is as follows: plane, sphere, hyperboloid, etc., i.e., the theoretical design surface shape of a heliostat is formed as a plane, sphere, hyperboloid, etc.
The attitude information of the target heliostat is azimuth angle, pitch angle and the like of the target heliostat; of course, other information may also be included, which is not limited herein, and may be used as the case may be, and all are within the scope of the present application.
The azimuth angle and the altitude angle of the sun can be obtained through date and time or real-time monitoring.
And simulating an image of the sun reflected by the target heliostat, namely simulating an image of the sun reflected by an ideal heliostat, by combining the parameters of the structural size, the theoretical design surface shape, the attitude information of the target heliostat and the azimuth angle/altitude angle of the sun and the solar brightness distribution function, and taking the image as a theoretical image.
Specifically, firstly, fitting is performed by using a function based on the brightness distribution condition of the solar image acquired by the solar image acquisition device to form a solar brightness distribution function; secondly, controlling the reflecting light spot center of the target heliostat to the central position of the heliostat image acquisition device, and recording the azimuth angle/pitch angle and date and time of the target heliostat; confirming the azimuth/altitude angle of the sun at the moment based on the date and time of the target heliostat; and simulating an image of the heliostat after reflecting the solar brightness distribution function at the moment by combining the structural size and the theoretical design surface shape of the heliostat, and the recorded azimuth/elevation angle and date time of the target heliostat, the solar azimuth angle/elevation angle and the solar brightness distribution function, and taking the image as a theoretical image.
In the embodiment, an image simulating the reflection of the sun on an ideal heliostat is provided, and is used as a theoretical image, so that a comparison basis is provided for the follow-up determination of the detection result of the target heliostat, and the accuracy and the detection efficiency of the detection result are improved; namely, based on an optical imaging principle, the heliostat surface shape is rapidly detected by utilizing machine vision.
Optionally, step S104 is to compare the theoretical image with the heliostat image to obtain a surface shape detection result of the target heliostat, and includes:
(1) And squaring the inverse function of the heliostat image to obtain the inverse function of the heliostat image.
Specifically, the inverse function is
Wherein the radiation intensity distribution of the sun is assumed to be axisymmetric and denoted as B (epsilon) =b 0f(ε),B0 as the radiation intensity of the sun center point; epsilon is the angular position of the sun center; k ij (P) is the square of the inverse function of the heliostat image; b (M' ij, P) is a heliostat image; k ij (P) is the inverse function.
The inverse function square may be performed on a plurality of heliostat images to obtain an inverse function of each heliostat image.
(2) And determining the partial derivative of the wavefront error of the target heliostat according to the inverse function of the heliostat image.
The wavefront error is: the difference between the wavefront shape of the light beam after passing through the optical system and the ideal wavefront. In general, wavefront errors can be calculated by measuring aberrations of an optical system, where aberrations refer to deviations in imaging position due to light beams passing through different optical paths after passing through the optical system.
Specifically, the partial derivative of the wavefront error (WFE, W (P)) of the solar mirror reflection is determinedAndWherein,For the partial derivative on the x-axis,Is the partial derivative on the y-axis. The formula used to obtain the partial derivative is:
δx 'and δy' are the offset of the camera in the x and y directions. K 22(p)、K12(p)、K11(p)、K12 (P) is the inverse function of the acquired heliostat images B (M' 22,P)、B(M'12,P)、B(M'11,P)、B(M'12, P), respectively.
(3) Determining optical aberration of the theoretical image, removing the optical aberration from the partial derivative, and performing matrix transformation to obtain a surface slope error.
The theoretical image is an image obtained according to a reference optical surface, and the posture information of the reference optical surface is the same as the posture information of the target heliostat.
In particular, the optical aberration of the reference optical surface can be calculated by means of ray tracing softwareAndThe angle A (azimuth angle) and the angle H (pitch angle) of the reference optical surface are the same as the azimuth angle and the pitch angle of the target heliostat when the target heliostat is acquired, and the wavefront error is eliminated from the optical difference phaseAndObtaining a difference value, which can beAndThe wavefront error is corrected.
A transformation matrix is applied to the corrected wavefront error (WFE) slope, converting it to a surface slope error. The transformation matrix and surface slope error are shown in the following equation:
Wherein, AndIs the surface slope error.
(4) Reconstructing the surface shape error of the target heliostat according to the surface slope error, and obtaining the actual surface shape of the target heliostat according to the surface shape error and the theoretical image.
From the surface slope error of the resulting heliostatAndAnd reconstructing the heliostat surface shape error based on the slope error to obtain a target heliostat surface shape error delta (P), and combining the reference optical surface z R (P) corresponding to the reference theoretical image to obtain an actual surface shape z (P) of the target heliostat. The formula adopted for determining the actual surface shape of the target heliostat is as follows: z (P) =z R (P) +Δ (P).
In general, the reference optical surface is an ideal planar or spherical mirror with a focal length equal to the distance D from the heliostat to the target plane.
Optionally, before the step S102 of collecting the sun image by the sun image obtaining device and collecting the heliostat image of the sun reflected by the heliostat image obtaining device, the method further includes:
and controlling a solar image acquisition device to automatically track the sun and acquire a solar image.
Specifically, a tracking control instruction is sent to a solar image acquisition device, and after the solar image acquisition device receives the tracking instruction, the solar image acquisition device automatically tracks the sun and acquires a solar image. The corresponding instruction of automatic tracking and collecting can be synthesized into one instruction, namely, after receiving the corresponding instruction, the automatic tracking and collecting are carried out. The automatic tracking and the acquisition can also be independent instructions, namely, the automatic tracking is carried out when the instruction corresponding to the tracking is received, and the acquisition is carried out when the instruction corresponding to the acquisition is received.
Optionally, controlling the solar image acquisition device to automatically track the sun includes:
Controlling an automatic tracking device in the solar image acquisition device to automatically track the sun; and controlling a solar industrial camera arranged on the automatic tracking device in the solar image acquisition device to acquire a solar image.
Specifically, an instruction corresponding to tracking is sent to an automatic tracking device in the solar image acquisition device, and the automatic tracking device automatically tracks the sun after receiving the instruction; and sending a command corresponding to the acquisition to a solar industrial camera in the solar image acquisition device, wherein the solar industrial camera acquires a solar image of the sun.
Optionally, in step S101, the center of the reflected light spot of the target heliostat is controlled to the acquisition port of the heliostat image acquisition device; before the heliostat image acquisition device is installed on the heat absorption tower, the heliostat image acquisition device further comprises:
Firstly, acquiring working states of all heliostats in a heliostat field; and secondly, determining a target heliostat needing to detect the surface shape according to the working state of each heliostat.
It should be noted that at least one heliostat is disposed in the heliostat field, and the heliostat reflects its light spot into the heat absorption tower during normal operation.
When the surface shape detection is required to be carried out on the heliostat in the heliostat field, the working state of the heliostat can be firstly obtained, whether the working state of the heliostat accords with the detection condition is judged, for example, if the heliostat is in a fault or other abnormal running states, the heliostat does not accord with the detection condition, and the opposite is true; and taking the heliostat meeting the detection condition as a target heliostat.
When the number of heliostats meeting the detection conditions is multiple, the heliostats meeting the detection conditions can be detected one by one, and can be processed in parallel, so that the heliostats meeting the detection conditions are not particularly limited, and the heliostats meeting the detection conditions can be within the protection scope of the application according to actual conditions.
Another embodiment of the present application provides a heliostat surface detection system.
Referring to fig. 2, the heliostat profile detection system comprises: a solar image acquisition device 2, a heliostat image acquisition device 3, a control device 4 and a processing device 5.
The sun image acquisition device 2 is used for acquiring sun images.
The heliostat image acquisition device 3 is mounted on the heat absorption tower 6.
The processing device 5 is connected to the heliostat 1, the solar image acquisition device 2, and the heliostat image acquisition device 3 via the control device 4, respectively. The heliostat is a target heliostat.
Specifically, the control device 4 is connected to the solar image acquisition device 2, the heliostat image acquisition device 3, and the target heliostat 1, respectively, and acquires the attitude information of the target heliostat 1 in real time, and controls the operation of the solar image acquisition device 2 and the heliostat image acquisition device 3.
The processing device 5 analyzes and processes the images acquired by the solar image acquisition device 2 and the heliostat image acquisition device 3 through the control device 4, and obtains heliostat shape information according to algorithm calculation.
The processing device 5 combines with the control device 4 to implement the heliostat surface detection method provided in the above embodiment.
The specific process of the heliostat surface shape detection method is not described here in detail, and the details refer to the heliostat surface shape detection method provided in the above embodiment.
The processing device 5 may be a computer, although other forms are not excluded and will not be described in detail here.
The specific control process can be as follows: the processing device 5 controls the solar image acquisition device 2 to track the sun and acquire a solar image through the control device 4; the processing means 5 controls the heliostat image acquisition means 3 mounted on the heat absorption tower 6 by the control means 4 to acquire an image of the sun in the target heliostat 1, that is, heliostat image. The virtual sun imaging distribution, that is, the theoretical image, on the target heliostat 1 is constructed based on the sun image acquired by the sun image acquisition device 2. And comparing and analyzing the theoretical image with the heliostat image to obtain the surface shape distribution condition of the target heliostat 1, namely the surface shape detection result of the target heliostat 1.
Alternatively, referring to fig. 3, the solar image acquisition apparatus 2 includes: an automatic tracking device 8 and a solar industrial camera 7 mounted on the automatic tracking device 8.
The automatic tracking device 8 is used for automatically tracking the sun.
Specifically, when the automatic tracking device 8 receives a tracking instruction from the control device 4, the automatic control device 4 automatically tracks the sun.
The solar industrial camera 7 is used for capturing solar images.
Specifically, the mounting surface of the solar industrial camera 7 is parallel to the mounting surface of the automatic tracking device 8. The solar industrial camera 7 is adjusted by following the automatic tracking device 8, namely, the solar industrial camera 7 can acquire the solar image in real time.
Optionally, referring to fig. 4, the heliostat image acquisition device 3 includes: a guard structure 11, a cradle head 10 and a heliostat industrial camera 9 mounted on the cradle head 10.
The cradle head 10 and the heliostat industrial camera 9 are both arranged on the protective structure 11.
The pan/tilt head 10 is used for performing horizontal/pitching biaxial adjustment and displaying azimuth angle and pitch angle. That is, the pan/tilt head 10 has a horizontal/tilt biaxial adjustment function, and is capable of displaying horizontal and tilt angle information.
And the heliostat industrial camera 9 is used for collecting heliostat images reflected by the heliostats.
Specifically, the installation surface of the heliostat industrial camera 9 is parallel to the installation surface of the cradle head 10. The heliostat industrial camera 9 is adjusted by following the cradle head 10, that is, the heliostat industrial camera 9 can acquire heliostat images in real time.
Optionally, the number of heliostat industrial cameras 9 in the heliostat image acquisition device 3 is 1 or more. The number of heliostat industrial cameras 9 is not particularly limited here, and may be as appropriate, and is within the scope of the present application. The solar industry images are the same and will not be described in detail here.
In the heliostat surface detection process, the control device 4 is connected with the automatic tracking device 8, and transmits a tracking instruction to the automatic tracking device 8, and the automatic tracking device 8 receives and executes the tracking instruction of the control device 4.
The control device 4 is connected with the solar industrial camera 7, controls the solar industrial camera 7 to operate, and sets key parameters of the solar industrial camera 7, wherein the key parameters can be aperture, focal length, exposure and the like.
The control device 4 is in communication connection with the target heliostat 1, receives attitude information and working state of the target heliostat 1, and controls the target heliostat 1 to reflect the spot center to the position of the heliostat industrial camera 9 according to the position information of the heliostat image acquisition device 3.
The control device 4 is connected with the cradle head 10, controls the horizontal/pitching direction operation of the cradle head 10, and receives the horizontal/pitching angle information of the cradle head 10.
The control device 4 is connected with the heliostat industrial camera 9, controls the heliostat industrial camera 9 to operate, and sets key parameters of the heliostat industrial camera 9, wherein the key parameters can be aperture, focal length, exposure and the like.
The solar industrial camera 7 and the heliostat industrial camera 9 are connected to the processing device 5, and key parameters of the solar industrial camera 7 and the heliostat industrial camera 9 are adjusted by the processing device 5. The key parameters may be: the aperture, the focal length and the exposure are respectively the same in value, so that the working camera can observe all and clear imaging of the sun and the heliostat; such parameters remain unchanged during heliostat surface detection after being fixed.
Specifically, the heliostat surface detection system may operate as follows:
Step1, the control device 4 sends a tracking instruction to the automatic tracking device 8, and the automatic tracking device 8 starts tracking the sun.
And 2, the processing device 5 transmits heliostat number information to be detected to the control device 4 according to the working states of all heliostats in the heliostat field. The heliostat number information is the number information of the target heliostat 1.
Specifically, if the target heliostat 1 is operating normally, the number information of the target heliostat 1 is directly transmitted to the control device 4, and if the target heliostat 1 is faulty or in other abnormal operating states, the number information of the next target heliostat 1 is transmitted to the control device 4.
And 3, after receiving the serial number information of the target heliostat 1, the control device 4 sends a control instruction to the target heliostat 1, and controls the reflecting light spot center of the target heliostat 1 to the position of the heliostat industrial camera 9.
The heliostat industrial camera 9 is mounted on the heat absorption tower 6, so that the adjusted reflection light spot center is still on the heat absorption tower 6, and the operation of the heliostat is not affected.
Step 4, the control device 4 simultaneously sends instructions to the solar industrial camera 7 and the heliostat industrial camera 9 to respectively shoot a solar image and a heliostat image, and the acquired solar image and heliostat image are transmitted to the processing device 5; and simultaneously, the attitude information of the current heliostat and the attitude information of the cradle head 10 are transmitted to the processing device 5.
And 5, the processing device 5 calculates the theoretical image of the sun on the target heliostat 1 according to the received sun image, the serial number information of the target heliostat 1, the attitude information of the heliostat and the attitude information of the cradle head 10 in a simulation mode, compares the theoretical image with the heliostat image acquired by the heliostat industrial camera 9, and obtains the surface shape distribution condition of the target heliostat 1 by combining an algorithm.
Features described in the embodiments in this specification may be replaced or combined, and identical and similar parts of the embodiments may be referred to each other, where each embodiment focuses on differences from other embodiments. In particular, for a system or system embodiment, since it is substantially similar to a method embodiment, the description is relatively simple, with reference to the description of the method embodiment being made in part. The systems and system embodiments described above are merely illustrative, wherein the elements illustrated as separate elements may or may not be physically separate, and the elements shown as elements may or may not be physical elements, may be located in one place, or may be distributed over a plurality of network elements. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment. Those of ordinary skill in the art will understand and implement the present invention without undue burden.
Those of skill would further appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both, and that the various illustrative elements and steps are described above generally in terms of functionality in order to clearly illustrate the interchangeability of hardware and software. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (10)
1. A method for heliostat shape detection, comprising:
When the surface shape detection of the heliostat is required, controlling the center of a reflection light spot of the target heliostat to an acquisition port of the heliostat image acquisition device; the heliostat image acquisition device is arranged on the heat absorption tower;
collecting a sun image through a sun image acquisition device, and collecting a heliostat image of the sun reflected by the target heliostat through the heliostat image acquisition device;
constructing a theoretical image of the simulated sun in the target heliostat according to the sun image, the attitude information of the target heliostat and the attitude information of the heliostat image acquisition device; the gesture information includes: azimuth and pitch;
and comparing the theoretical image with the heliostat image to obtain a surface shape detection result of the target heliostat.
2. The heliostat surface shape detection method according to claim 1, wherein the constructing simulates a theoretical image of the sun in the target heliostat according to the sun image, attitude information of the target heliostat, and attitude information of the heliostat image acquisition device; the posture information includes: azimuth and pitch angles, including:
Fitting the brightness distribution of the solar image to obtain a solar brightness distribution function;
Acquiring attitude information of the target heliostat when the center of the reflection light spot is adjusted to the acquisition port of the heliostat image acquisition device;
Confirming azimuth/altitude angle of the sun;
And simulating an image of the sun reflected by the target heliostat by combining the structural size of the target heliostat, the theoretical design surface shape, the attitude information of the target heliostat, the azimuth angle/altitude angle of the sun and the solar brightness distribution function to obtain the theoretical image.
3. The heliostat surface shape detection method of claim 1, wherein comparing the theoretical image and the heliostat image to obtain the surface shape detection result of the target heliostat comprises:
squaring the inverse function of the heliostat image to obtain the inverse function of the heliostat image;
Determining a partial derivative of the wavefront error of the target heliostat according to the inverse function of the heliostat image;
Determining the optical aberration of the theoretical image, removing the optical aberration from the partial derivative and performing matrix transformation to obtain a surface slope error;
Reconstructing the surface shape error of the target heliostat according to the surface slope error, and obtaining the actual surface shape of the target heliostat according to the surface shape error and the reference optical surface corresponding to the theoretical image.
4. The heliostat shape detection method of claim 1, further comprising, prior to the acquiring of the sun image by the sun image acquisition device and the acquiring of the heliostat image of the sun after reflection by the heliostat image acquisition device:
and controlling the solar image acquisition device to automatically track the sun and acquire a solar image.
5. The heliostat profile detection method of claim 4, wherein the controlling the solar image acquisition device to automatically track the sun comprises:
Controlling an automatic tracking device in the solar image acquisition device to automatically track the sun; and controlling a solar industrial camera arranged on the automatic tracking device in the solar image acquisition device to acquire a solar image.
6. The heliostat surface shape detection method according to claim 1, wherein the center of the reflected light spot of the target heliostat is controlled to the acquisition port of the heliostat image acquisition device; the heliostat image acquisition device is installed before on the heat absorption tower, still includes:
acquiring the working state of each heliostat in a heliostat field;
and determining a target heliostat needing to detect the surface shape according to the working state of each heliostat.
7. A heliostat surface detection system, comprising: a solar image acquisition device, a heliostat image acquisition device, a control device and a processing device;
The solar image acquisition device is used for acquiring a solar image;
the heliostat image acquisition device is arranged on the heat absorption tower;
The processing device is respectively connected with the heliostat, the solar image acquisition device and the heliostat image acquisition device through the control device;
the processing device, in combination with the control device, implements the heliostat surface detection method of any one of claims 1-6.
8. The heliostat surface detection system of claim 7, wherein the solar image acquisition device comprises: an automatic tracking device and a solar industrial camera mounted on the automatic tracking device;
the automatic tracking device is used for automatically tracking the sun;
the solar industrial camera is used for collecting solar images.
9. The heliostat surface detection system of claim 7, wherein the heliostat image acquisition device comprises: the device comprises a protection structure, a cradle head and a heliostat industrial camera arranged on the cradle head;
The cradle head and the heliostat industrial camera are both arranged on the protection structure;
The cradle head is used for carrying out horizontal/pitching double-shaft adjustment and displaying azimuth angle and pitch angle;
the heliostat industrial camera is used for collecting heliostat images reflected by the heliostats.
10. The heliostat surface detection system of claim 9, wherein the number of heliostat industrial cameras in the heliostat image acquisition device is 1 or more.
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