Photovoltaic tracking precision measuring device, method, system and photovoltaic power station

Abstract

The application provides a photovoltaic tracking precision measuring device, method, system and photovoltaic power station, comprising a main body, a detection chamber is arranged on the main body, the detection chamber is provided with a slit, the slit is a circular arc shape; a photosensitive sensor comprising a photosensitive detection area, the photosensitive detection area is arranged in the detection chamber, the center position of the photosensitive detection area coincides with the center of the slit, the length direction of the photosensitive detection area is perpendicular to the projection of the slit, by using the method, the device is not limited by the photosensitive detection range, is not affected by the different solar elevation angles caused by seasonal changes, does not need to adjust the measurement direction again, eliminates the geometric nonlinear problem of the straight slit, solves the large-range elevation angle measurement tracking precision problem, and improves the detection precision.

Description

Technical Field

[0001] This application relates to the field of photovoltaic tracking technology, and in particular to a photovoltaic tracking accuracy measurement device, method, system, and photovoltaic power station. Background Technology

[0002] Tracking brackets actively adjust the orientation of modules by tracking the sun's position in real time to maximize the use of solar radiation, thereby increasing power generation and achieving higher power generation revenue. Depending on the structural system, tracking brackets are divided into single-axis and dual-axis types. Single-axis brackets are further divided into horizontal single-axis and inclined single-axis brackets. Currently, the mainstream products on the market are mainly single-axis, including horizontal single-axis and inclined single-axis brackets.

[0003] The photovoltaic tracking accuracy measurement device is installed on the tracking bracket. It measures the tracking accuracy using methods such as shadow observation, pinhole four-quadrant photodetector, pinhole photosensitive sensor (area CCD), and slit photosensitive sensor (line CCD). However, the measurement is limited by the CCD's light-sensing range. When the solar altitude angle changes due to seasonal variations, the measurement range is exceeded, requiring readjustment of the measurement orientation and recalibration. Summary of the Invention

[0004] This application provides a photovoltaic tracking accuracy measurement device, method, system, and photovoltaic power station to at least solve the above-mentioned technical problems existing in the prior art.

[0005] According to a first aspect of this application, a photovoltaic tracking accuracy measuring device is provided, comprising: a main body including a detection chamber and a slit, the slit being at least partially arc-shaped; and a photosensor including a photosensor detection area disposed within the detection chamber, the center of the slit coinciding with the photosensor detection area.

[0006] In one embodiment, the main body includes an arc-shaped sheet, the slit is disposed on the arc-shaped sheet, and the center line of the arc-shaped sheet coincides with the photosensitive detection area.

[0007] In one embodiment, the center of the slit coincides with the center of the photosensitive detection area, and the projection shape of the slit into the detection chamber is perpendicular to the photosensitive detection area.

[0008] In one embodiment, the arc-shaped sheet includes opposing first and second sidewalls, the slit is formed between the first and second sidewalls, the thickness of the first and second sidewalls is no more than 0.1 mm, the width of the slit is no more than 0.3 mm, and the curvature of the slit is no less than 90°.

[0009] In one embodiment, the detection chamber is made of an opaque, thermally conductive material, and the inner wall of the detection chamber is provided with a light-absorbing layer.

[0010] In one embodiment, the photosensitive detection area has no fewer than 3600 pixels, the width of each pixel is no less than 5μm, the length of each pixel is no less than 150μm, and the pixels are arranged along the width direction of the pixels.

[0011] In one embodiment, an arc-shaped filter is disposed on the slit, the arc-shaped filter is sealed to the main body, and the center line of the arc-shaped filter coincides with the center line of the arc-shaped plate.

[0012] In one embodiment, the arc-shaped filter is made of neutral density optical glass.

[0013] In one embodiment, the device further includes a control computing circuit, which is electrically connected to the photosensor; the control computing circuit includes an analog-to-digital converter chip, a data buffer chip, and an electronic control chip; wherein the analog-to-digital converter chip is used to convert the analog signal from the photosensor into a digital signal; the data buffer chip is used to buffer the digital signal; and the electronic control chip is used to read the digital signal from the data buffer chip, perform data analysis using the centroid method, and obtain the deviation angle value.

[0014] According to a second aspect of this application, a method for measuring the accuracy of photovoltaic tracking is provided. The method includes: acquiring a sensing signal from a slit through a photosensitive detection area; preprocessing the sensing signal to obtain a preprocessed signal located within the maximum peak value range; determining the signal peak position of the preprocessed signal and generating position information containing the signal peak position, wherein the signal peak position is located within the maximum peak value range; and determining a corresponding deviation angle value based on the radius of the slit and the position information of the signal peak position.

[0015] In one possible implementation, determining the signal peak position of the preprocessed signal and generating position information containing the signal peak position includes: within the maximum peak range, determining the position information of the corresponding signal peak position using the centroid method based on the sequence number of pixels and the voltage value.

[0016] In one possible implementation, determining the corresponding deviation angle value based on the radius of the slit and the position information of the signal peak includes: processing the radius of the slit and the position of the signal peak using an arctangent function to obtain the deviation angle value.

[0017] According to a third aspect of this application, a photovoltaic tracking accuracy measurement system is provided, the system comprising: a preprocessing module, configured to acquire a sensing signal from a slit through a photosensitive detection area, preprocess the sensing signal to obtain a preprocessed signal located within the maximum peak value range; a determination module, configured to acquire the preprocessed signal, determine the signal peak position of the preprocessed signal, and generate position information containing the signal peak position, wherein the signal peak position is located within the maximum peak value range; and a calculation module, configured to acquire the position information and determine a corresponding deviation angle value based on the radius of the slit and the signal peak position.

[0018] In one embodiment, the determining module includes: within the maximum peak range, determining the position information of the corresponding signal peak position using the centroid method based on the sequence number of pixels and the voltage value.

[0019] In one embodiment, the calculation module includes: processing the radius of the slit and the position of the signal peak using an arctangent function to obtain a deviation angle value.

[0020] According to a fourth aspect of this application, a photovoltaic power station is provided, including a tracking bracket on which a photovoltaic tracking accuracy measuring device as described in any of the first aspects of this application is provided.

[0021] In one embodiment, the main shaft of the tracking bracket is horizontally mounted along the north-south direction and is capable of rotating relative to the east-west direction; the projection of the slit of the photovoltaic tracking accuracy measuring device faces the north-south direction and is perpendicular to the east-west direction.

[0022] The present application provides a photovoltaic tracking accuracy measurement device, method, system, and photovoltaic power station. By setting a slit in the detection chamber and setting a photosensitive detection area at the center of the slit in the detection chamber, the device is not limited by the photosensitive detection range, is not affected by the different solar altitude angles caused by seasonal changes, and does not require readjustment of the measurement orientation.

[0023] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of this application, nor is it intended to limit the scope of this application. Other features of this application will become readily apparent from the following description. Attached Figure Description

[0024] The above and other objects, features, and advantages of exemplary embodiments of this application will become readily apparent from the following detailed description taken in conjunction with the accompanying drawings. Several embodiments of this application are illustrated in the drawings by way of example and not limitation, in which:

[0025] In the accompanying drawings, the same or corresponding reference numerals indicate the same or corresponding parts.

[0026] Figure 1 An exploded view of a photovoltaic tracking accuracy measuring device according to an embodiment of this application is shown;

[0027] Figure 2 A cross-sectional schematic diagram of a photovoltaic tracking accuracy measuring device according to an embodiment of this application is shown;

[0028] Figure 3 A schematic diagram of the hardware circuit of a photovoltaic tracking accuracy measurement device according to an embodiment of this application is shown;

[0029] Figure 4 A schematic diagram of the preprocessed numerical data set according to an embodiment of this application is shown;

[0030] Figure 5 A flowchart illustrating a photovoltaic tracking accuracy measurement method according to an embodiment of this application is shown;

[0031] Figure 6 A schematic diagram of a photovoltaic tracking accuracy measurement system according to an embodiment of this application is shown;

[0032] Figure 7 A schematic diagram showing the installation direction of a photovoltaic tracking accuracy measuring device according to an embodiment of this application is illustrated.

[0033] The following are the labels in the diagram: 1. Main body; 11. Arc-shaped piece; 111. Mounting groove; 12. Slit piece; 121. Slit; 13. Detection chamber; 14. Mounting chamber; 15. Mounting base; 2. Photosensitive sensor; 21. Photosensitive detection area; 22. RF follower; 23. AFE inverter; 3. Arc-shaped filter; 4. Control and calculation circuit; 41. Analog-to-digital-to-analog converter chip; 42. Data buffer chip; 43. Electronic control chip; 5. Wire. Detailed Implementation

[0034] To make the objectives, features, and advantages of this application more apparent and understandable, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0035] See Figures 1 to 3 According to a first aspect of this application, a photovoltaic tracking accuracy measuring device is provided, comprising: a main body 1, including a detection chamber 13 and a slit 121, wherein the main body 1 is provided with the slit 121, and the slit 121 is at least partially arc-shaped; and a photosensor 2, including a photosensor detection area 21, wherein the photosensor detection area 21 is disposed in the detection chamber 13, and the center of the slit 121 coincides with the center of the photosensor detection area 21.

[0036] The device provided in this application includes a main body 1, which can be a combination of rectangular and semi-cylindrical shapes. A detection chamber 13 and a mounting chamber 14 are formed within the main body 1. The detection chamber 13 is a dark chamber used to mount a photosensor 2, and the mounting chamber 14 is a mounting cavity used to mount various other major electronic devices besides the photosensor 2.

[0037] The main body 1 is mainly made of opaque material. The main body 1 can be one or more layers. Since the detection chamber 13 needs to have high thermal conductivity, the material used to make the detection chamber 13 and the material used to make the mounting chamber 14 can be the same or different.

[0038] Specifically, the material used to make the detection chamber 13 is selected to be an opaque metal or non-metal, such as stainless steel plate. To improve the thermal conductivity of the detection chamber 13, it can be made of a high thermal conductivity opaque material, such as aluminum alloy, to reduce the thermal radiation interference caused by the temperature rise of the detection chamber 13 due to heat absorption. To prevent light from being refracted or reflected after entering the detection chamber 13, a light-absorbing layer can also be provided on the inner wall of the detection chamber 13. The light-absorbing layer can be paint, velvet, wallpaper, etc., containing light-absorbing particles.

[0039] The detection chamber 13 includes an arc-shaped piece 11, which forms a slit 121. The arc-shaped piece 11 can be made of stainless steel or aluminum alloy and is located on two surfaces of the detection chamber 13 facing away from the mounting chamber 14. The arc-shaped piece 11 can be integrally formed with the main body 1 or connected to the main body 1 by splicing. The arc-shaped piece 11 can be a single piece, in which case the slit 121 is formed on the arc-shaped piece 11. Alternatively, two or more arc-shaped pieces 11 can be spliced ​​together at a close but non-contact distance to form the slit 121. The arc-shaped piece 11 is at least partially cylindrical, and its centerline is the axis of its cylindrical structure. The axis of the arc-shaped piece 11 is located within the detection chamber 13, and is parallel to the connecting bottom edge of the detection chamber 13 and the mounting chamber 14 to facilitate the installation of the photosensitive element.

[0040] For ease of installation, in this method, the arc-shaped piece 11 includes two cylindrical stainless steel arc-shaped pieces larger than 1 / 4 of a circle and a slit piece 12. One end of the arc-shaped piece 11 is connected to the top edge of the main body 1, and the other end is connected to the bottom edge of the main body 1. An installation groove 111 is formed between the two stainless steel arc-shaped pieces for the slit piece 12 to be inserted. The curvature of the installation groove 111 is not less than 90°.

[0041] The slit element 12 is an independently formed 90° arc-shaped structure. The thickness of the slit element 12 can be the same as or different from that of the arc-shaped piece 11. In this embodiment, the slit element 12 includes a first sidewall and a second sidewall. A cutting edge is formed on the opposing surfaces of both the first and second sidewalls. The slit 121 is located between the first and second sidewalls. The cutting edge thickness of both the first and second sidewalls does not exceed 0.1 mm. The thinner the cutting edge, the thinner the slit element 12, and the better the detection accuracy. The distance between the first and second sidewalls does not exceed 0.3 mm; correspondingly, the closer the distance between the first and second sidewalls, the better the detection accuracy. To ensure the stability of the slit element 12 structure, the thickness of the main body of the slit element 12 can be greater than the cutting edge thickness.

[0042] Correspondingly, the arc of slit 121 is 90° or greater than 90°. Since the solar altitude angle changes under different weather conditions throughout the year, the measurement range changes. In order to make the measuring device applicable to real-time measurement and tracking accuracy in any location, any season, and any weather, the arc of slit 121 in this embodiment needs to be set to about 90° so that the tracking angle can be determined at the winter and summer solstices in most parts of the world, and the maximum power generation can be obtained through the rotation of the main shaft.

[0043] In one specific implementation scenario, the width of the slit 121 is selected as any one of 0.1mm, 0.2mm, and 0.3mm. The curvature of the slit 121 is consistent with the curvature of the arc-shaped piece 11, and the center of the slit 121 is located on the axis of the arc-shaped piece 11, so that the distance from any point on the slit 121 to the center of the slit 121 is equal.

[0044] The photosensitive sensor 2 can be selected as a linear CCD sensor. Its photosensitive detection area 21 is detected by a linear photosensitive element. When installing the linear photosensitive element of the photosensitive sensor 2, it can be mounted on the contact edge of the detection chamber 13 near the mounting chamber 14. For ease of installation, a mounting base 15 inclined towards the slit 121 can be formed on the bottom surface of the detection chamber 13 near the mounting chamber 14. The linear photosensitive element is connected to the mounting base 15, so that the photosensitive detection area 21 of the linear photosensitive element is positioned in the detection chamber 13 along the length of the arc-shaped plate 11 along the bottom contact edge, and coincides with the axis of the arc-shaped plate 11. The center of the photosensitive detection area 21 is also aligned with the center of the slit 121, meaning the center of the linear photosensitive element coincides with the center of the slit 121, and the center of the linear photosensitive element faces the slit 121. This solves the geometric nonlinearity problem of the measurement technology, resulting in higher measurement accuracy.

[0045] In one embodiment, an arc-shaped filter 3 is provided on the slit 121. The arc-shaped filter 3 is sealed to the main body 1. A gap is left between the arc-shaped filter 3 and the slit 121. The axis of the arc-shaped filter 3 coincides with the axis of the arc-shaped plate 11. The arc-shaped filter 3 is made of neutral density optical glass. The neutral density optical glass reduces the transmittance of light at different wavelengths by 40-60%.

[0046] To limit the peak intensity of solar radiation and seal the slit 121, enabling the entire device to operate outdoors, the device provided in this embodiment also includes an arc-shaped filter 3. The arc-shaped filter 3 is made of uniform neutral density (ND) glass with equal ability to reduce different wavelengths of light. It can be selected from ND glass with a transmittance between 40% and 60%, specifically ND glass with a transmittance of around 50%, including but not limited to grades such as ZAB50 and ZAB65. A gap can be left between the arc-shaped filter 3 and the slit 121. The arc-shaped filter 3 is used to reduce the background radiation value of the sky. To ensure the light reduction effect, the gap distance between the arc-shaped filter 3 and the slit 121 remains consistent at any position.

[0047] In one embodiment, the photosensor 2 is a linear CCD chip. The photosensor detection area has no fewer than 3600 pixels, which are arranged along the width direction, with a pixel width of no less than 5μm and a pixel length of no less than 150μm.

[0048] Specifically, a higher number of pixels, or an increase in pixel width, leads to a longer photosensitive area, which in turn increases the range of the maximum measurable offset angle. For example, when the total length of the photosensitive area is 3648 pixels × 8μm pixel width, the range of the maximum measurable offset angle is ±20°. The length of the pixels can affect the theoretical accuracy of the measured maximum offset angle; for instance, when the length of the pixels in the photosensitive area is 200μm, the theoretical accuracy of the maximum measurable offset angle is no more than 0.01°.

[0049] The control and calculation circuit 4 of the device is installed in the mounting chamber 14. The control and calculation circuit 4 includes an analog-to-digital converter chip 41, a data buffer chip 42, and an electronic control chip 43. The control and calculation circuit 4 is electrically connected to the photosensor 2 located in the detection chamber 13 via a wire 5. The control and calculation circuit 4 is used to perform analog-to-digital conversion and data analysis on the analog signal from the photosensor 2 to obtain the deviation angle value.

[0050] The photosensor 2 in this embodiment is either a linear CCD chip or a PSD chip. The following description uses a linear CCD chip as an example. The linear CCD sensor is used to achieve photoelectric conversion. When the linear CCD sensor senses sunlight, it generates voltage signals for each pixel, i.e., analog signals.

[0051] The value measured by each pixel on the linear CCD chip is the sum of the irradiance values ​​of all points in the sky along the Earth's meridian direction that pass through the slit 121 and are projected as arc-shaped normal rays. Rays projected as arc-shaped non-normal rays cannot illuminate the photosensitive element of the CCD sensor.

[0052] To meet performance requirements, this application selects a linear CCD chip with no fewer than 3600 pixels, a pixel width of no less than 5μm, a pixel length of no less than 150μm, a wavelength range of 200-1100nm, and features electronic shutter function and flexible adjustment of integration time. By integrating time, the width modulation of the SH signal and the adjustment of pixel exposure can be achieved, enabling the output signal to reach the desired amplitude.

[0053] Specifically, in one implementation scenario, this application embodiment selects Toshiba's TCD1304DG linear CCD chip as the photodetector. The TCD1304DG is a cost-effective CCD chip with 3648 pixels, a pixel size (W×H) of 8×200µm, and a wavelength range of 200~1100nm. The TCD1304DG's spectral response curve shows a peak response wavelength of 550nm and a long-wavelength limit of 1100nm, exhibiting high efficiency in the visible light range. Furthermore, the TCD1304DG features an electronic shutter function, making it a linear CCD device with flexible integration time adjustment. By modulating the width of the integration time (SH signal), the exposure of the pixels can be adjusted, achieving the desired amplitude of the output signal.

[0054] A radio frequency follower 22 and an AFE (Analog Front End) inverter 23 are provided between the linear CCD chip and the control calculation circuit 4. The radio frequency follower 22 and the AFE inverter 23 are used to process the analog signal into a signal that conforms to the input amplitude range of the analog-to-digital converter chip 41.

[0055] To enhance the driving capability, an RF follower 22, i.e., a first-stage emitter follower circuit, is added to the analog output (OS) of the linear CCD chip. The signal is then processed by the AFE to be inverted and conform to the input amplitude range of the analog-to-digital converter chip 41.

[0056] In one embodiment, the analog-to-digital converter chip 41 is used to convert the analog signal from the photosensitive sensor 2 into a digital signal; the data buffer chip 42 is used to buffer the digital signal in a register; and the electronic control chip 43 is used to read the digital signal from the data buffer chip 42, perform data analysis using the center of gravity method, and obtain the deviation angle value.

[0057] The analog-to-digital converter chip 41 is selected as a processing chip used to convert analog signals from an image sensor CCD into digital signals. It is chosen to have three channels for analog signal input, 16-bit data input, and 8-bit data selection output. Specifically, the AD9826 from Analog Devices (ADI) can be selected.

[0058] The data cache chip 42 can be a chip with dual-port RAM to improve the utilization efficiency of the CPLC's internal storage space and enhance data processing capabilities. Specifically, the IDT7134 chip can be selected.

[0059] The electronic control chip 43 can be selected as a main control CPLC chip, or a chip with a built-in user non-volatile memory module (FLASH). Alternatively, a chip with a clock frequency of 250 MHz or higher can be selected to facilitate numerical analysis of digital signals.

[0060] Specifically, the main control CPLC chip can be selected from Altera's MAX II series of complex programmable logic devices (2PLDs), specifically the EPM570T100C5. It features high density and excellent performance, built-in user-defined non-volatile FLASH memory, an internal clock frequency of up to 300 MHz, a 100-pin MBGA package, and 570 logic elements (LEs). The raw CCD waveform, consisting of voltage values ​​from 3648 pixels, is cached in a 16-bit data group in a FIFO register. This data group is then read by the CPLC for numerical analysis.

[0061] In one embodiment, the electronic control chip 43 is used to obtain the maximum radiation position by performing median filtering, first differentiation, range merging, integration and centroid position calculation on the digital signal, and to determine the deviation angle value based on the maximum radiation position.

[0062] The electronic control chip 43 can perform data analysis on the data set according to the photovoltaic tracking accuracy measurement method provided in the embodiments of this application.

[0063] See Figure 4 and Figure 5 According to a second aspect of this application, a photovoltaic tracking accuracy measurement method is provided, the method comprising: operation 101, acquiring a sensing signal from a slit through a photosensitive detection area, preprocessing the sensing signal to obtain a preprocessed signal located within the maximum peak value range; operation 102, determining the signal peak position of the preprocessed signal and generating position information containing the signal peak position, wherein the signal peak position is located within the maximum peak value range; and operation 103, determining the corresponding deviation angle value based on the radius of the slit and the position information of the signal peak position.

[0064] The method provided in this application is applied to a photovoltaic tracking accuracy measurement device. It acquires the induced signal from the slit through the photosensitive detection area of ​​a linear CCD array, and then preprocesses the induced signal to adjust the integration time of the CCD. During preprocessing, a maximum peak value range is set; for example, this maximum peak value range can be set to 98-99% of the maximum voltage value, such as between 3.234 and 3.267. In low illumination conditions, the desired amplitude of the output signal can be achieved by increasing the light integration time; when the illumination is strong, the desired amplitude of the output signal can be achieved by shortening the light integration time.

[0065] The preprocessing algorithm analysis process specifically includes: median filtering, first differentiation, range merging, integration, and centroid location calculation to output the maximum radiation location.

[0066] The maximum radiation location result is a relative value obtained by measuring the maximum radiation range on a linear CCD chip and calculating it using the centroid method. This can effectively reduce the influence of environmental radiation and various types of thermal radiation.

[0067] The processing algorithm includes the following steps:

[0068] First, a median filtering operation is performed. The median filtering algorithm is used to process the digital signal read from the main control CPLC chip to eliminate outliers and noise, which is most effective in eliminating pulse interference and image scanning noise. After filtering, the curve becomes relatively smooth.

[0069] Then, a differentiation operation is performed to determine the maximum peak range. The pixel waveform value is numerically differentiated once, and a threshold with an absolute value close to zero is set. The minimum value within the threshold range is the peak position point. The first differentiation threshold is adjusted through testing to obtain an optimal value, and the initial value can be set starting from 0.0002.

[0070] Next, a range merging operation is performed. The mean value of the pixel waveform values ​​is calculated, and a weighting value is set. The positions on both sides of each peak point where the voltage value is greater than the weighted mean are retained. If any points within the retained range overlap with other peak points, the retained ranges should be merged. By changing the weighting value, the size of the retained range can be adjusted to find an appropriate irradiation interval.

[0071] Then, perform the integration operation, summing the integrals over each retained range, leaving only one retained range with the maximum integral value.

[0072] Next, the centroid position is determined. Within this integration range, based on the pixel sequence and voltage values ​​within the maximum peak range, the location of the maximum signal peak is calculated using the centroid method. The specific formula is as follows:

[0073]

[0074] in,

[0075] y: Indicates the position of the peak value of the output signal of the linear CCD chip;

[0076] Ln: Represents the sequence number of pixel units in a linear CCD chip;

[0077] X: Represents the voltage value corresponding to the linear CCD chip.

[0078] After completing the preprocessing operation, the angle calculation module is used to calculate the angle deviation angle according to the following formula:

[0079]

[0080] in,

[0081] L0: Represents the sequence number of the CCD pixel unit located in the middle position.

[0082] R: Represents the radius of the slit arc surface.

[0083] α: Represents the deviation angle.

[0084] δ: Represents the pixel width; in this specific scenario, δ = 0.008.

[0085] See Figure 6 According to a third aspect of this application, a photovoltaic tracking accuracy measurement system is provided. The system includes: a preprocessing module 201, used to acquire a sensing signal from a slit through a photosensitive detection area, preprocess the sensing signal to obtain a preprocessed signal within the maximum peak value range; a determination module 202, used to acquire the preprocessed signal, determine the signal peak position of the preprocessed signal, and generate position information containing the signal peak position, wherein the signal peak position is within the maximum peak value range; and a calculation module 203, used to acquire the position information and determine the corresponding deviation angle value based on the radius of the slit and the signal peak position.

[0086] According to a fourth aspect of this application, a photovoltaic power station is provided, including a tracking bracket on which a photovoltaic tracking accuracy measuring device as described in any of the first aspects of this application is provided.

[0087] Specifically, the measuring device provided in the first aspect of this application can be mounted on the spindle of a single-axis tracking system, and the tracking spindle rotates together with it. This device can be used in most parts of the world, and no matter what weather changes occur, there is no need to readjust the installation angle.

[0088] To further improve accuracy, the installation angle can be related to the installation latitude and longitude. In areas north or south of the Tropic of Cancer, horizontal installation with the main axis is sufficient. In areas within the Tropic of Cancer and Tropic of Capricorn, an installation angle with the main axis is required, the angle being the angle between the local latitude and the tropics. This device has a maximum measurement offset of ±20 degrees and a theoretical measurement accuracy of 0.01 degrees.

[0089] See Figure 7 In one embodiment, the tracking bracket's main shaft is horizontally mounted along the north-south direction and is capable of rotating relative to the east-west direction; the forward projection of the slit 121 on the main body 1 faces the north-south direction and is perpendicular to the east-west direction. Specifically, when the photovoltaic tracking accuracy measuring device is located in the Northern Hemisphere, the slit 121 faces south, and conversely, when the photovoltaic tracking accuracy measuring device is located in the Southern Hemisphere, the slit 121 faces north.

[0090] To further improve accuracy, the installation angle can be related to the installation latitude and longitude. In areas north or south of the tropics, horizontal installation with the main axis is sufficient. In areas within the tropics, an installation angle with the main axis is required, the angle being the angle between the local latitude and the tropics. This device measures a maximum offset angle of ±20 degrees, with a theoretical measurement accuracy of 0.01 degrees. With this setup, after the photovoltaic tracking accuracy measurement device is installed, no readjustment of the installation angle is required regardless of weather changes.

[0091] The linear CCD chip described in this application has a flexible adjustment function. The device automatically adjusts the CCD's integration time, thus allowing the maximum radiation angle of the single-axis tracking system to be found even in cloudy, scattering weather. After the tracking system adjusts the tracking angle via the TCU, the maximum radiation angle can be obtained, increasing power generation. It should be noted that when the voltage value at the peak point is less than the weighted average, a retention range cannot be found. At this point, the meteorological conditions have shifted to high scattering weather, and the maximum radiation angle cannot be determined using this method; other methods are needed to find the maximum radiation angle.

[0092] It should be understood that the various forms of processes shown above can be used to rearrange, add, or delete steps. For example, the steps described in this disclosure can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution disclosed in this application can be achieved, and this is not limited herein.

[0093] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "a plurality of" means two or more, unless otherwise explicitly specified.

[0094] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A photovoltaic tracking accuracy measuring device, characterized in that, include: The main body (1) includes a detection chamber (13) and a slit (121), the slit (121) being at least partially arc-shaped; A photosensitive sensor (2) includes a photosensitive detection area (21) disposed within the detection chamber (13); The center of the slit (121) coincides with the center of the photosensitive detection area (21), and the projection shape of the slit (121) into the detection chamber (13) is perpendicular to the photosensitive detection area (21). The width of the slit (121) is no more than 0.3 mm, and the curvature of the slit is no less than 90°.

2. The apparatus according to claim 1, characterized in that, The main body (1) includes an arc-shaped piece (11), and the slit (121) is disposed on the arc-shaped piece (11). The center line of the arc-shaped piece (11) coincides with the photosensitive detection area (21).

3. The apparatus according to claim 2, characterized in that, The arc-shaped piece (11) includes opposing first and second sidewalls, and the slit (121) is formed between the first and second sidewalls, the thickness of the first and second sidewalls not exceeding 0.1 mm.

4. The apparatus according to claim 1, characterized in that, The detection chamber (13) is made of an opaque thermally conductive material, and the inner wall of the detection chamber (13) is provided with a light-absorbing layer.

5. The apparatus according to claim 1, characterized in that, The photosensitive detection area (21) has no less than 3600 pixels, the width of each pixel is no less than 5μm, the length of each pixel is no less than 150μm, and the pixels are arranged along the width direction of the pixels.

6. The apparatus according to claim 2, characterized in that, An arc-shaped filter (3) is provided on the slit (121), and the arc-shaped filter (3) is sealed to the main body (1). The center line of the arc-shaped filter (3) coincides with the center line of the arc-shaped plate (11).

7. The apparatus according to claim 6, characterized in that, The arc-shaped filter (3) is made of neutral density optical glass.

8. The apparatus according to any one of claims 1-7, characterized in that, The device further includes a control computing circuit (4) and is electrically connected to the photosensor (2); the control computing circuit (4) includes an analog-to-digital converter chip (41), a data cache chip (42), and an electronic control chip (43); wherein, The analog-to-digital converter chip is used to convert the analog signal from the photosensitive sensor (2) into a digital signal; The data cache chip (42) is used to cache the digital signal; The electronic control chip (43) is used to read the digital signal of the data cache chip (42), and to perform data analysis using the center of gravity method to obtain the deviation angle value.

9. A method for measuring the accuracy of photovoltaic tracking, characterized in that, The method is applied to the photovoltaic tracking accuracy measurement device as described in any one of claims 1-8, comprising: The sensing signal from the slit is acquired through the photosensitive detection area, and the sensing signal is preprocessed to obtain a preprocessed signal within the range of the maximum peak value. Determine the signal peak position of the preprocessed signal and generate position information containing the signal peak position; The corresponding deviation angle value is determined based on the radius of the slit and the position information of the signal peak.

10. The method according to claim 9, characterized in that, The process of determining the signal peak position of the preprocessed signal and generating position information containing the signal peak position includes: Within the maximum peak range, the position information of the corresponding signal peak is determined using the centroid method based on the sequence number of pixels and the voltage value.

11. The method according to claim 9 or 10, characterized in that, The step of determining the corresponding deviation angle value based on the radius of the slit and the position information of the signal peak includes: The radius of the slit and the position of the signal peak are processed using the arctangent function to obtain the deviation angle value.

12. A photovoltaic tracking accuracy measurement system, used to perform the photovoltaic tracking accuracy measurement method as described in any one of claims 9-11, characterized in that, The system includes: The preprocessing module (201) is used to acquire the sensing signal from the slit through the photosensitive detection area, preprocess the sensing signal, and obtain a preprocessed signal within the maximum peak value range. The determining module (202) is used to acquire the preprocessed signal, determine the signal peak position of the preprocessed signal, and generate position information containing the signal peak position; The calculation module (203) is used to obtain the position information and determine the corresponding deviation angle value based on the radius of the slit and the position of the signal peak.

13. A photovoltaic power station, characterized in that, It includes a tracking bracket, on which a photovoltaic tracking accuracy measuring device as described in any one of claims 1-8 is provided.

14. The photovoltaic power station according to claim 13, characterized in that, The main shaft of the tracking bracket is installed horizontally along the north-south direction and can rotate relative to the east-west direction; The projection of the slit in the photovoltaic tracking accuracy measurement device faces north-south and is perpendicular to the east-west direction.

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