A heliostat field analysis method and system based on combined spots

Abstract

The application discloses a heliostat field analysis method based on combined light spots, which comprises the following steps: obtaining a target blank background image, the target being used for receiving reflected light spots projected by heliostats in a heliostat field; obtaining a target foreground image after the heliostats in the heliostat field project the reflected light spots on the target; obtaining an actual full-field combined light spot formed by the heliostat field on the target by making a difference between the gray scales of the target foreground image and the target blank background image; and comparing the actual full-field combined light spot with a preset theoretical full-field combined light spot, so that an abnormal area in the actual full-field combined light spot can be obtained. The method solves the coupling problem of different heliostat tracking accuracies, target point design factors and light spot surface shape error factors, and can quickly complete the analysis work of the heliostat field.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of solar heat utilization, and particularly relates to a heliostat field analysis method and system based on combined light spots. BACKGROUND

[0002] Solar thermal power generation is a main way of current solar heat utilization. The current solar thermal power generation adopts a tower type solar thermal power generation method. A tower type solar thermal power generation system uses heliostats tracking the sun in real time to reflect sunlight to a heat absorber located on an absorption tower, so as to generate high-temperature and high-pressure steam by heating a heat absorption working medium in the heat absorber, and drive a steam turbine generator set to generate power.

[0003] In order to make the heat absorber work normally, it is necessary to ensure that the combined light spot flow density distribution projected by the heat collection field onto the heat absorber is uniform. The abnormal conditions of the combined light spot include:

[0004] 1. Local energy flow density is too low, causing freezing of molten salt and other heat absorption media.

[0005] 2. Local energy flow density is too high, causing local overheating of the heat absorber and affecting the service life of the heat absorber.

[0006] 3. The combined light spot overflows in the up-down direction of the heat absorber, the temperature of the protective layer exceeds the material safety limit, and the protective plate is irreversibly burned out.

[0007] 4. The combined light spot overflows too much in the left-right direction of the heat absorber, causing sunlight not to be projected onto the effective heat absorption surface of the heat absorber, and further causing low truncation efficiency.

[0008] The reasons for the abnormality of the combined light spot include the following points:

[0009] 1. The tracking accuracy of the heliostat is too low, that is, the heliostat cannot project its light spot to the expected target point position, resulting in the situation of pointing east and west.

[0010] 2. The unreasonable setting of the running target point of the heliostat leads to the overall abnormality of the combined light spot.

[0011] 3. The shape of the light spot of the heliostat is inconsistent with the expectation due to the face shape error, such as the actual light spot shape of the heliostat being larger than the theoretical elliptical shape or protruding more in a certain direction, and the large part and the protruding part are abnormal points of the light spot.

[0012] (1) Existing heliostat tracking accuracy detection technology

[0013] The prior art has low efficiency and long cycle for tracking accuracy of heliostat and detection of heliostat surface type, and there is no scheme for effectively detecting target point distribution of a large number of heliostats in a heliostat field in the prior art, and since the tracking accuracy of heliostat, the heliostat surface type and the target point distribution are three independent abnormal factors, the prior art cannot determine the three abnormal factors at the same time through one detection, and therefore, the actual cause of abnormal combination light spot in the heliostat field cannot be quickly and comprehensively determined. SUMMARY

[0014] To solve the above problems, the purpose of the present application is to provide a heliostat field analysis and rectification method and system based on combination light spot, which solves the problem of coupling of different heliostat tracking accuracy, target point design factors and light spot surface type error factors, and can quickly complete the analysis of the heliostat field.

[0015] To achieve the above purpose, the technical scheme of the present application is: a heliostat field analysis method based on combination light spot, comprising the following steps: acquiring a target blank background image, the target being used to receive reflected light spots projected by heliostats in a heliostat field; acquiring a target foreground image after the heliostats in the heliostat field project the reflected light spots onto the target; obtaining an actual full-field combination light spot formed by the heliostat field on the target by subtracting the gray scale of the target foreground image from the gray scale of the target blank background image; and comparing the actual full-field combination light spot with a preset theoretical full-field combination light spot, so as to obtain an abnormal area in the actual full-field combination light spot.

[0016] Preferably, the step of acquiring the target foreground image after the heliostats in the heliostat field project the reflected light spots onto the target comprises: dividing the heliostats in the heliostat field into a plurality of batches, each batch projecting the reflected light spots onto the target, and acquiring a batch target foreground image corresponding to each batch after the reflected light spots are projected onto the target.

[0017] Preferably, the step of obtaining the actual full-field combination light spot formed by the heliostat field on the target by subtracting the gray scale of the target foreground image from the gray scale of the target blank background image comprises: subtracting the gray scale of the batch target foreground image corresponding to each batch from the gray scale of the target blank background image to obtain a batch combination light spot formed by each batch on the target, and combining the batch combination light spots to form the actual full-field combination light spot.

[0018] Preferably, the target points of the heliostats in the same batch on the target do not coincide and can be clearly identified; or, the heliostats in the same batch are divided into several groups, the target points of the heliostats in each group on the target are located in a preset target area, and the preset target areas corresponding to the groups do not coincide and can be clearly identified.

[0019] Preferably, the heliostats in the same batch are controlled by a mirror field control system to realize synchronous rotation.

[0020] Preferably, the target blank background image is obtained by: two or more batches sharing the same target blank background image; or, each batch obtaining a corresponding target blank background image before projecting the reflected light spot on the target.

[0021] Preferably, after obtaining the abnormal area in the actual full-field combined light spot, the following steps are further included: locating the corresponding batch causing the abnormality of the actual full-field combined light spot according to the obtained abnormal area, and defining it as an abnormal batch; obtaining the batch combined light spot formed by the abnormal batch on the target by subtracting the gray scale of the target blank background image from the batch target foreground image corresponding to the abnormal batch; and locating the abnormal heliostat or abnormal group in the abnormal batch by comparing the batch combined light spot with the theoretical batch combined light spot corresponding to the abnormal batch.

[0022] Preferably, after locating the abnormal group, the reflected light spots of the heliostats in the abnormal group are simultaneously or individually projected on the target, and the actual reflected light spots of the heliostats in the abnormal group on the target are obtained; the abnormal heliostat in the abnormal group is located by comparing the actual reflected light spot corresponding to each heliostat in the abnormal group with the corresponding theoretical reflected light spot; and when the reflected light spots of the heliostats in the abnormal group are simultaneously projected on the target, the target points of the reflected light spots of the heliostats in the abnormal group on the target do not coincide.

[0023] Preferably, the target points of the heliostats in the same batch on the target cover the entire target; or, the preset target areas corresponding to the groups in the same batch cover the entire target, and the energy of the reflected light spot projected by each group on the target does not exceed the highest energy flow density that can be tolerated per unit area of the target.

[0024] Preferably, the method for acquiring the target foreground image after the heliostat in the heliostat field projects the reflected light spot on the target further comprises: during the acquisition of the adjacent two batches of batch target foreground images, moving the reflected light spot of the heliostat in the next batch to a test preparation point while acquiring the batch target foreground image corresponding to the current batch; after the acquisition of the batch target foreground image corresponding to the current batch is completed, moving the reflected light spot of the current batch to the surface of the heat absorber, and moving the reflected light spot of the heliostat in the next batch from the test preparation point to the target.

[0025] Preferably, the target target point on which the reflected light spot of any heliostat is projected on the target is determined according to the heat absorber target point on which the reflected light spot of the heliostat is projected on the surface of the heat absorber, wherein H b = H r + H bc - H rc , T r is the coordinate of the heat absorber target point, H r is the height of the position where the heat absorber target point is located, R r is the corresponding heat absorber radius at the height where the heat absorber target point is located, C r is the coordinate of the center point of the heat absorber, H rc is the height of the position where the center point of the heat absorber is located, C b is the coordinate of the center point of the target corresponding to the heliostat, H bc is the height of the position where the center point of the target corresponding to the heliostat is located, R b is the corresponding target radius at the height where the target target point is located, H b is the height of the position where the target target point is located, T b is the coordinate of the target target point.

[0026] Based on the same concept, the present application also provides a heliostat field analysis system based on combined light spots, which uses any of the above-mentioned methods to analyze the heliostat field, comprising: a heliostat field comprising a plurality of heliostats; a target arranged in the circumferential direction of the heat absorber for receiving the reflected light spot projected by the heliostat in the heliostat field; a mirror field control system for controlling the heliostats in the heliostat field to project the reflected light spot onto the target according to a predetermined program; a target camera for shooting a target blank background image and a target foreground image; an analysis module for determining the abnormal heliostat in the heliostat field according to the target blank background image, the target foreground image, and the preset theoretical combined light spot information and / or theoretical single heliostat reflected light spot information.

[0027] After adopting the above technical solutions, compared with the prior art, the present application has the advantages that:

[0028] 1、The present application can quickly obtain the abnormal area in the actual full-field combined light spot by comparing the actual full-field combined light spot with the preset theoretical full-field combined light spot, and then can quickly locate the heliostat that occurs abnormity in the heliostat field, thereby narrowing down the scope of investigation and rectification, and without the need to detect the tracking accuracy, running target point rationality and heliostat surface type of each heliostat in the heliostat field, thereby realizing the quick analysis and identification of abnormal heliostats, and effectively improving the work efficiency.

[0029] 2、Due to the large number of heliostats in the heliostat field, the energy flow density that the target surface can withstand is limited, if the reflected light spots of all heliostats are projected onto the target surface at one time, the target may be burned out, which may cause safety hazards, therefore, the actual full-field combined light spot cannot be obtained by projecting the reflected light spots of all heliostats onto the target surface at one time, the present application divides the heliostats in the heliostat field into several batches, and each time a batch of heliostats projects the reflected light spots onto the target surface, and then the obtained combined light spots of each batch are spliced to obtain the actual full-field combined light spot, which can effectively solve the problem of limited ability of the target surface to withstand the reflected light spots. And each time a batch of heliostat reflected light spots is projected onto the target and covers the entire target, it meets the requirement of as many heliostats as possible working at the same time within the heat energy flow density bearing range of the target surface, and improves the work efficiency.

[0030] 3、In the present application, the heliostats in the same batch can be controlled by the mirror field control system to rotate synchronously, thereby not being limited by the power supply rotation angle capability of the mirror field control system (due to the large number of heliostats in the heliostat field, the mirror field control system is limited by the communication load and the power supply load, and the mirror field control system cannot control all heliostats in the heliostat field to rotate at the same time, and the mirror field control system can only control part of the heliostats in the heliostat field to rotate at the same time), which further improves the work efficiency.

[0031] 4、The heliostat field analysis system of the present application divides the heliostats in each batch into several groups, so that the target points of the heliostats in each group on the target are located in the preset target area, and the preset target areas corresponding to the groups do not overlap and can be clearly identified. By using this design, more reflected light spots projected by the heliostats can be received on the target under the condition that the reflected light spot receiving surface of the target does not change, that is, the number of heliostats in each batch is greatly increased, and the heliostats can be checked in groups during troubleshooting, thereby greatly improving work efficiency. For example, the reflected light spots projected by the heliostats in the same group completely overlap on the target, so the multiple reflected light spots projected by the multiple heliostats in the group on the target actually only occupy the area of one reflected light spot on the reflected light spot receiving surface of the target. Therefore, more reflected light spots projected by the heliostats can be received on the target under the condition that the size of the reflected light spot receiving surface of the target does not change.

[0032] 5、On the one hand, the present application makes each batch share the same target blank background image, so that the time for obtaining the target blank background image can be greatly saved, and the work efficiency is improved. On the other hand, the present application can also obtain a target blank background image corresponding to each batch of heliostats before the heliostats in the corresponding batch project reflected light spots on the target, so that the light spot recognition of the weak sunlight condition and the sunny side can be improved.

[0033] 6、The present application further shortens the analysis operation time and improves the analysis operation efficiency by reasonably controlling the motion trajectories and time of the heliostats in the previous batch and the heliostats in the next batch. BRIEF DESCRIPTION OF DRAWINGS

[0034] The specific embodiments of the present application will be further described in detail below with reference to the accompanying drawings, in which:

[0035] Figure 1 The present application is based on a combination of light spot heliostat field analysis system schematic diagram;

[0036] Figure 2 The present application is based on a combination of light spot heliostat field analysis system schematic diagram;

[0037] Figure 3 The present application is based on a combination of light spot heliostat field analysis system schematic diagram;

[0038] Figure 4 The present application is based on a combination of light spot heliostat field analysis system schematic diagram;

[0039] Figure 5 The present application is based on a combination of light spot heliostat field analysis system schematic diagram;

[0040] Figure 6 The combined foreground image after the target foreground image is spliced. DETAILED DESCRIPTION

[0041] The application will be described in further detail below with reference to the drawings and embodiments. The advantages and features of the application will be more apparent from the following description and claims. It should be noted that the drawings are very simplified and use non-precise ratios, only for the purpose of conveniently and clearly assisting in the description of the embodiments of the application.

[0042] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the application are only used to explain the relative positional relationship, movement condition, etc. between components in a certain posture (as shown in the drawings), and if the certain posture changes, the directional indications will also change accordingly.

[0043] Embodiment one

[0044] The embodiment provides a heliostat field analysis method based on combined light spots, including the following steps:

[0045] A target blank background image is acquired, and the target 201 is used to receive reflected light spots projected by heliostats in a heliostat field 1;

[0046] A target foreground image after the reflected light spots are projected onto the target 201 by the heliostats in the heliostat field 1 is acquired;

[0047] An actual full-field combined light spot formed by the heliostat field 1 on the target 201 is acquired by performing a difference operation on the gray scales of the target foreground image and the target blank background image;

[0048] An abnormal area in the actual full-field combined light spot can be obtained by comparing the actual full-field combined light spot with a preset theoretical full-field combined light spot.

[0049] The target blank background image represents a target image when the reflected light spots are not projected onto the target 201, and the target foreground image represents a target image when the reflected light spots are projected onto the target 201.

[0050] By comparing the actual full-field combined light spot with the preset theoretical full-field combined light spot, the abnormal area in the actual full-field combined light spot can be quickly obtained, and then the heliostat in the heliostat field 1 that is abnormal can be quickly located, so that the range of checking and rectification is reduced, and the tracking accuracy, the rationality of a running target point, and the heliostat surface type of each heliostat in the heliostat field 1 do not need to be detected, and then the quick analysis and identification of the abnormal heliostat can be realized, and the work efficiency is effectively improved.

[0051] Preferably, the method for obtaining the target front view image after the heliostat in the heliostat field 1 projects the reflected light spot on the target 201 comprises: dividing the heliostat in the heliostat field 1 into batches, each batch projecting the reflected light spot on the target 201, and obtaining the batch target front view image corresponding to each batch after the reflected light spot is projected on the target 201.

[0052] In the technical solution of the present application, by dividing the heliostat in the heliostat field 1 into batches, obtaining the target front view image corresponding to each batch, and then subtracting the target front view image of each batch from the target blank background image to obtain the reflected light spot image, it can be analyzed whether the reflected light spot of each batch of heliostat has the problem of target point deviation, unreasonable target point setting or light spot size not meeting the theoretical expectation, and then the specific batch of heliostat is located, which facilitates the relevant personnel to narrow down the investigation and rectification range and improve the work efficiency.

[0053] Preferably, the above method for obtaining the combined light spot of the whole field can comprise the following two methods:

[0054] I. First, the target front view image corresponding to each batch is subtracted from the target blank background image and then spliced.

[0055] II. First, the target front view images of all batches are spliced with the target blank background image and then subtracted.

[0056] Preferably, the target blank background image is obtained by: two or more batches (such as every 10 batches) share the same target blank background image; or, each batch obtains a target blank background image corresponding thereto before projecting the reflected light spot on the target 201.

[0057] On the one hand, two or more batches share the same target blank background image, which can greatly save the time for obtaining the target blank background image and improve the work efficiency; on the other hand, the present application can also obtain a target blank background image corresponding to each batch before the heliostat in the corresponding batch projects the reflected light spot on the target 201, which can improve the light spot recognition in weak sunlight conditions and the sunny side.

[0058] Considering that there are sunny side and shady side relative to the heat absorber 3 / target 201, the light intensity and energy flow density of different directions are different, so a plurality of target cameras 202 are arranged around the target 201 to obtain images at the same time, which can eliminate the error caused by different directions. At the same time, since the total time of the scheme analysis operation of the present embodiment is relatively short, the target front view images of different batches can also be subtracted from the same background image to obtain the combined light spot in some cases, further improving the operation efficiency.

[0059] Preferably, the actual full-field combined light spot formed by the heliostat field 1 on the target 201 is obtained by subtracting the gray scale of the target foreground image and the target blank background image, including: subtracting the gray scale of each batch of batch target foreground images from the gray scale of the target blank background image respectively, to obtain the batch combined light spot formed by each batch on the target 201, and the actual full-field combined light spot is formed by splicing and combining each batch combined light spot.

[0060] The target foreground image and the blank target background image obtained by each batch of target cameras 202 are first subtracted and then spliced to obtain the actual full-field combined light spot, and only one operation is needed with the theoretical full-field combined light spot when positioning the anomaly, thereby improving the efficiency of anomaly positioning and the overall analysis efficiency. Figure 6 The combined foreground image after splicing of the plurality of target foreground images in the embodiment.

[0061] Further, the calculation of the light spot image by the gray scale subtraction method is: let the gray scale of the i-th batch target foreground image be G f(i) , and the gray scale of the corresponding target blank background image be G b(i) , then the actual combined light spot image B = ∑G f(i) -G b(i) .

[0062] Referring to Figure 2 The schematic process of subtracting the target foreground image and the target blank background image to obtain the reflected light spot image is shown. The target 201 and its markers are included in the target foreground image 4, and the target foreground image 4 is subtracted from the target blank background image 5 to obtain the reflected light spot Figure 6 .

[0063] Preferably, each heliostat in the same batch is controlled by the mirror field control system to realize synchronous rotation.

[0064] Each heliostat in the same batch is controlled by the mirror field control system to realize synchronous rotation, and further improves the work efficiency without being limited by the power supply rotation angle capability of the mirror field control system (since the number of heliostats in the heliostat field 1 is large, the mirror field control system is limited by the communication load and the power supply load, and the mirror field control system cannot control all heliostats in the heliostat field 1 to rotate at the same time, and the mirror field control system can only control part of the heliostats in the heliostat field 1 to rotate at the same time at the same time), thereby further improving the work efficiency.

[0065] Preferably, the method for acquiring the target foreground image after the heliostat in the heliostat field 1 projects the reflected light spot onto the target 201 further comprises: during the acquisition of the batch target foreground images of two adjacent batches, moving the reflected light spot of the heliostat in the next batch to a test preparation point while acquiring the batch target foreground image corresponding to the current batch; after the acquisition of the batch target foreground image corresponding to the current batch is completed, moving the reflected light spot of the current batch to the surface of the heat absorber 3, and moving the reflected light spot of the heliostat in the next batch from the test preparation point to the target 201.

[0066] For all batches sharing the same target blank background image, since the target blank background image does not need to be taken between two adjacent batches, there is no need to wait for the instruction to move the reflected light spot of the heliostat in the next batch into the range of the target 201 after the reflected light spot of the heliostat in the previous batch moves out of the range of the target 201, thereby improving the work efficiency.

[0067] Reasonably controlling the action trajectory and time of the heliostat in the previous batch and the heliostat in the next batch further shortens the analysis time and improves the analysis efficiency. After the reflected light spot of the heliostat in the previous batch completely leaves the target surface range of the target 201, the reflected light spot of the heliostat in the next batch enters the target surface range of the target 201, which can avoid the target surface of the target 201 from having a too high energy flow density and thus adversely affecting the target 201.

[0068] Preferably, the method for acquiring the target foreground image after the heliostat in the heliostat field 1 projects the reflected light spot onto the target further comprises: during the acquisition of the batch target foreground images of two adjacent batches, moving the reflected light spot of the heliostat in the next batch to a test preparation point while acquiring the batch target foreground image corresponding to the current batch; after the acquisition of the batch target foreground image corresponding to the current batch is completed, moving the reflected light spot of the current batch to the surface of the heat absorber 3, and moving the reflected light spot of the heliostat in the next batch from the test preparation point to the target 201.

[0069] Most of the two-axis tracking heliostats need to change the tracking angles of both the elevation angle and the azimuth angle. The first dimension adjustment mechanism can be an elevation angle adjustment or an azimuth angle adjustment, and the corresponding second dimension adjustment mechanism is an azimuth angle adjustment or an elevation angle adjustment. Since the motor start-stop time is relatively long, in order to speed up the analysis efficiency, a test preparation point is set, and the heliostat in the next batch moves to the preparation point position during the operation of the heliostat in the previous batch, and only one angle (elevation angle or azimuth angle) needs to be turned from the preparation point position to the test operation position.

[0070] Specifically, referring to Figure 5For example, taking the movement of the reflection spot of the heliostat from the target point 14 on the heat absorber 3 to the target point 15 on the target 201 at the time of testing as an example, two preliminary point coordinates of the elevation angle or the azimuth angle are point 16 and point 17, and the light spot movement trajectories are 18 and 19, respectively. The trajectory 18 passes through the target 201 and interferes with the heliostat that is taking a photo, while the trajectory 19 does not pass through the target 201. In this embodiment, the point 17 is selected in advance by the control algorithm to avoid the interference.

[0071] Preferably, the target points of the heliostats in the same batch on the target 201 do not coincide with each other and can be clearly identified; or the heliostats in the same batch are divided into a plurality of groups, the target points of the heliostats in each group on the target 201 are located in a preset target region, and the preset target regions corresponding to the groups do not coincide with each other and can be clearly identified.

[0072] The heliostats in each batch are divided into a plurality of groups, so that the target points of the heliostats in each group on the target 201 are located in a preset target region, and the preset target regions corresponding to the groups do not coincide with each other and can be clearly identified. By using this design, more reflection spots of the heliostats can be received on the reflection spot receiving surface of the target 201 under the condition that the reflection spot receiving surface of the target 201 is unchanged, that is, the number of heliostats in each batch is greatly increased, and the heliostats can be checked in groups during troubleshooting, thereby greatly improving the work efficiency. For example, the reflection spots of the heliostats in the same group completely coincide on the target 201, and then the multiple reflection spots of the heliostats in the group to the target 201 actually only occupy the area of one reflection spot on the reflection spot receiving surface of the target 201. Therefore, more reflection spots of the heliostats can be received on the reflection spot receiving surface of the target 201 under the condition that the size of the reflection spot receiving surface of the target 201 is unchanged.

[0073] In addition, according to the spatial distribution of the target points on the target 201, the heliostats are divided into different groups according to the principle that the target points are as same as possible or close to each other, and the number of heliostats in each group is limited according to the highest energy flow density that can be tolerated per unit area of the target 201 material, which adapts to the actual situation that the target 201 cannot project a large number of heliostat spots due to heat dissipation problems.

[0074] For example, Figure 3 and Figure 4 The spot image obtained by subtracting the foreground image from the background image is shown.

[0075] In Figure 3The group set 7, the group set 8 and the group set 9 represent group reflection light spot sets in different directions, respectively. Each group set has three light spots corresponding to the upper, middle and lower groups, and the light spots in different directions are arranged in a triangular manner, until the entire target 201 is covered. Since the groups are generally staggered, when the reflected light spot is abnormal, the range can be reduced to several groups, and the tracking accuracy of these groups is tested to further reduce the range, until the abnormal heliostat is located.

[0076] In Figure 4 The group set 10, the group set 11, the group set 12 and the group set 13 represent group light spot sets in different directions, respectively. Each group set has two light spots corresponding to the upper and lower groups, and the groups are arranged in an up-down staggered manner.

[0077] Figure 3 And Figure 4 The arrangement shown is only one of the two, and the arrangement between the group sets can also be arranged in any way that can be extended repeatedly, Figure 3 And Figure 4 The two ways do not limit the concept of the application.

[0078] Preferably, after obtaining the abnormal area in the actual full-field combined light spot, the method further comprises the steps of: locating the corresponding batch that causes the actual full-field combined light spot to be abnormal according to the obtained abnormal area, and defining the batch as an abnormal batch; and obtaining the batch combined light spot formed by the abnormal batch on the target 201 by subtracting the gray scale of the target blank background image from the gray scale of the batch target foreground image corresponding to the abnormal batch. By comparing the batch combined light spot with the theoretical batch combined light spot corresponding to the abnormal batch, the abnormal heliostat or the abnormal group in the abnormal batch can be located. If the positions of the actual reflected light spot and the theoretical reflected light spot corresponding to the abnormal group are consistent, but the sizes are inconsistent, it indicates that there is an abnormal heliostat in the abnormal group, and the actual mirror surface error is inconsistent with the theoretical design result. If the positions of the actual reflected light spot and the theoretical reflected light spot corresponding to the abnormal group are inconsistent, but the sizes are consistent, it indicates that there is an abnormal heliostat in the abnormal group, and the tracking accuracy is inconsistent with the theoretical design result. If the positions of the actual reflected light spot and the theoretical reflected light spot corresponding to the abnormal group are consistent, and the sizes are also consistent, it indicates that the tracking accuracy and the surface error of the heliostat in the abnormal group meet the requirements, and the accuracy of the absolute value of the energy calculation result at different positions of the target point (pointing point) of the designed heliostat needs to be considered. The target point of the heliostat needs to be redesigned according to the actual situation to solve the abnormality.

[0079] Preferably, after the abnormal group is located, the reflection spots of each heliostat in the abnormal group are projected onto the target 201 simultaneously or one by one, and the actual reflection spots of each heliostat in the abnormal group on the target 201 are obtained. By comparing the actual reflection spots of each heliostat in the abnormal group with the corresponding theoretical reflection spots, the abnormal heliostat in the abnormal group can be located. When the reflection spots of each heliostat in the abnormal group are projected onto the target 201 simultaneously, the target points of the reflection spots of each heliostat in the abnormal group on the target 201 do not coincide with each other.

[0080] Preferably, the target points of each heliostat in the same batch on the target 201 cover the entire target 201; or the preset target areas corresponding to each group in the same batch cover the entire target 201, and the reflection spot energy projected by each group on the target 201 does not exceed the highest energy flux density that can be tolerated per unit area of the target 201.

[0081] Because the number of heliostats in the heliostat field 1 is large, the energy flux density that can be tolerated by the surface of the target 201 is limited. If the reflection spots of all heliostats are projected onto the surface of the target 201 at one time, the target 201 may be burned, which poses a safety hazard. Therefore, the actual full-field combined spot cannot be obtained by projecting the reflection spots of all heliostats onto the surface of the target 201 at one time. By dividing the heliostats in the heliostat field 1 into several batches and projecting the reflection spots of a batch onto the surface of the target 201 each time, and then combining the combined spots of each batch to obtain the actual full-field combined spot, the problem of limited capacity of the surface of the target 201 to tolerate the reflection spots can be effectively solved. Moreover, the reflection spots of a batch of heliostats are projected onto the target 201 each time and cover the entire target 201, which meets the requirement of as many heliostats as possible working at the same time within the range of the heat energy flux density that can be tolerated by the surface of the target 201, and improves the work efficiency.

[0082] Preferably, the target point of the reflection spot of each heliostat on the target 201 is determined according to the heat absorber target point of the reflection spot of the heliostat on the surface of the heat absorber 3, wherein,

[0083] H b = H r + H bc - H rc ,

[0084]

[0085] T r is the coordinate of the heat absorber target point,

[0086] H r is the height of the position of the heat absorber target point,

[0087] R r is the radius of the receiver corresponding to the height of the target point of the receiver,

[0088] C r is the coordinate of the center point of the receiver,

[0089] H rc is the height of the position where the center point of the receiver is located,

[0090] C b is the coordinate of the center point of the corresponding target of the heliostat,

[0091] H bc is the height of the position where the center point of the corresponding target of the heliostat is located,

[0092] R b is the radius of the target corresponding to the height of the target point of the target,

[0093] H b is the height of the position where the target point is located,

[0094] T b is the coordinate of the target point.

[0095] By the above method, the corresponding relationship between the target point and the receiver target point can be accurately established, and the movement of the heliostat during analysis work is facilitated.

[0096] Embodiment Two

[0097] Referring to Figure 1 , the embodiment provides a heliostat field analysis system based on combined light spots, which analyzes the heliostat field by using any one of the above methods. The system comprises: a heliostat field 1 comprising a plurality of heliostats; a target 201 arranged in the circumferential direction of a receiver 3 for receiving reflected light spots projected by the heliostats in the heliostat field 1; a mirror field control system for controlling the heliostats in the heliostat field 1 to project the reflected light spots onto the target 201 according to a preset program; a target camera 202 arranged in the circumferential direction of the target 201 for shooting the target surface image of the target 201, for shooting a target blank background image and a target foreground image; an analysis module for determining abnormal heliostats in the heliostat field 1 according to the target blank background image, the target foreground image, and preset theoretical combined light spot information and / or theoretical single heliostat reflected light spot information.

[0098] The mirror field control system controls the heliostats in the heliostat field 1 to project the light spots on the target 201 circumferentially preset target points in batches according to a preset program, the target 201 circumferentially preset target points and the heat absorber 3 circumferentially target points have a preset corresponding relationship, the target camera 202 shoots the target 201 target surface image including the target blank background image without heliostat light spot projection and multiple sets of different batches of target foreground images of heliostat light spot projection, and the mirror field control system obtains the light spot image output analysis result based on the difference between the target blank background image and the different batches of target foreground images.

[0099] The heliostat field analysis system based on the combined light spot divides the whole combined light spot into batches for shooting, analyzes and splices, and further subdivides the range for checking by reducing the range for checking.

[0100] In a preferred embodiment, in order to establish the corresponding relationship between the target 201 circumferentially preset target points and the heat absorber 3 circumferentially target points, the target points on the heat absorber 3 and the target points on the target 201 are proportionally copied according to the height and radius difference, and the target points on the target 201 are formed, which retains the light spot offset properties caused by the design factors of the target points on the heat absorber 3.

[0101] Specifically, the target target point on the target 201 where the reflected light spot of any heliostat is projected is determined according to the heat absorber target point on the surface of the heat absorber 3 where the reflected light spot of the heliostat is projected, wherein,

[0102] H b = H r + H bc -H rc ,

[0103]

[0104] T r is the coordinate of the heat absorber target point,

[0105] H r is the height of the position where the heat absorber target point is located,

[0106] R r is the radius of the heat absorber corresponding to the height where the heat absorber target point is located,

[0107] C r is the coordinate of the center point of the heat absorber 3,

[0108] H rc is the height of the position where the center point of the heat absorber 3 is located,

[0109] C b is the coordinate of the center point of the target corresponding to the heliostat,

[0110] Hbc the height of the position of the center point of the corresponding target of the heliostat,

[0111] R b the radius of the corresponding target at the height of the target point,

[0112] H b the height of the position of the target point,

[0113] T b the coordinates of the target point.

[0114] According to the above method, the corresponding relationship between the circumferential preset target point of the target 201 and the circumferential target point of the heat absorber 3 can be accurately established, and the movement of the heliostat during analysis work is facilitated.

[0115] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the above-described system, device and unit can refer to the corresponding processes in the foregoing method embodiments, which will not be described herein.

[0116] The above embodiments are only used to illustrate the technical solutions of the present application, but not to limit it; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that the technical solutions recorded in the foregoing embodiments can still be modified, or some technical features can be replaced by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A heliostat field analysis method based on combined light spots, characterized in that, Includes the following steps: Acquire a blank background image of a target, wherein the target is used to receive the reflected light spot projected by the heliostat in the heliostat field; Acquire a foreground image of the target after the heliostat in the heliostat field projects the reflected light spot onto the target; This includes: dividing the heliostats in the heliostat field into several batches, with each batch projecting a reflected light spot onto the target, and acquiring the corresponding batch target foreground image after each batch projects the reflected light spot onto the target; The actual full-field combined light spot formed by the heliostat field on the target is obtained by subtracting the grayscale values ​​of the target foreground image and the target blank background image; including: subtracting the grayscale values ​​of the batch target foreground image corresponding to each batch and the target blank background image respectively to obtain the batch combined light spot formed by each batch on the target respectively, and forming the actual full-field combined light spot by splicing and combining the batch combined light spots; By comparing the actual full-field combined light spot with the preset theoretical full-field combined light spot, the abnormal regions in the actual full-field combined light spot can be obtained. Based on the obtained abnormal area, locate the corresponding batch that caused the abnormality of the actual full-field combined light spot, and define it as the abnormal batch. The difference in grayscale between the foreground image of the target corresponding to the abnormal batch and the blank background image of the target is used to obtain the batch combination spot formed by the abnormal batch on the target. By comparing the batch combination spot with the theoretical batch combination spot corresponding to the abnormal batch, the abnormal heliostat or abnormal group in the abnormal batch can be located.

2. The heliostat field analysis method based on combined light spots according to claim 1, characterized in that, The target points of each heliostat in the same batch on the target do not overlap and can be clearly identified; or, the heliostats in the same batch are divided into several groups, and the target points of the heliostats in each group are located within a preset target area on the target, and the preset target areas corresponding to each group do not overlap and can be clearly identified.

3. The heliostat field analysis method based on combined light spots according to claim 1, characterized in that, Each heliostat in the same batch is controlled by the mirror field control system to achieve synchronous rotation.

4. The heliostat field analysis method based on combined light spots according to claim 1, characterized in that, The acquisition of the target blank background image includes: two or more batches sharing the same target blank background image; or, each batch acquiring a corresponding target blank background image before projecting a reflected light spot onto the target.

5. The heliostat field analysis method based on combined light spots according to claim 2, characterized in that, After locating the abnormal group, the reflected light spots of each heliostat in the abnormal group are simultaneously or individually projected onto the target, and the actual reflected light spots of each heliostat in the abnormal group on the target are obtained. By comparing the actual reflected light spots of each heliostat in the abnormal group with the corresponding theoretical reflected light spots, the abnormal heliostat in the abnormal group can be located. When the reflected light spots of each heliostat in the anomaly group are simultaneously projected onto the target, the reflected light spots of each heliostat in the anomaly group do not overlap with each other at the target point on the target.

6. The heliostat field analysis method based on combined light spots according to claim 2, characterized in that, Each heliostat in the same batch covers the entire target with its target point. Alternatively, the preset target area corresponding to each group in the same batch covers the entire target, and the energy of the reflected light spot projected by each group onto the target does not exceed the highest energy flux density that the target can withstand per unit area.

7. The heliostat field analysis method based on combined light spots according to claim 1, characterized in that, The method for acquiring a target foreground image after the heliostat projects the reflected light spot onto the target in the heliostat field further includes: During the process of acquiring the target foreground images of two adjacent batches, while acquiring the target foreground image corresponding to the current batch, the reflected light spot of the heliostat in the next batch is moved to the test preparation point; after the target foreground image corresponding to the current batch is acquired, the reflected light spot of the current batch is moved to the surface of the receiver, and the reflected light spot of the heliostat in the next batch is moved from the test preparation point to the target.

8. The heliostat field analysis method based on combined light spots according to any one of claims 1-7, characterized in that, The target point on the target where the reflected light spot of any heliostat is projected onto the target is determined based on the target point on the absorber surface where the reflected light spot of the heliostat is projected onto the absorber surface, wherein, ， ， The coordinates of the target point of the heat absorber are given. The height of the target point of the heat absorber. The receiver radius is the distance from the target point of the receiver to the target location. The coordinates of the center point of the absorber are: The height is the position of the center point of the heat absorber. These are the coordinates of the center point of the target corresponding to the heliostat. This refers to the height of the center point of the target corresponding to the heliostat. The target radius is the distance from the target point to its height. The height of the target point is [height]. The coordinates of the target point are given.

9. A heliostat field analysis system based on combined light spots, comprising analyzing the heliostat field using the method described in any one of claims 1 to 8, characterized in that, include: A heliostat field, comprising several heliostats; A target positioned circumferentially to the receiver is used to receive reflected light spots projected by the heliostats in the heliostat field. The mirror field control system is used to control the heliostats in the heliostat field to project reflected light spots onto the target according to a preset program; Target camera, used to capture images of the target's blank background and foreground; The analysis module is used to determine the abnormal heliostats in the heliostat field based on the target blank background image, the target foreground image, and preset theoretical combined spot information and / or theoretical single heliostat reflected spot information.

Images