Detection equipment and detection method for photovoltaic cell panel

Abstract

The embodiment of the invention provides detection equipment and a detection method of a photovoltaic cell panel, relates to the technical field of photovoltaic power generation, and aims to solve the problem that the detection difficulty of a photoluminescence signal of the photovoltaic cell panel is large. The detection equipment comprises a lens, an adjustable filtering device, an image sensor and a processor, the adjustable light filtering device is used for filtering light converged to the image sensor through the lens and has a first light filtering wave band and a second light filtering wave band which can be switched; the first filtering wave band comprises a photoluminescence wave crest of the photovoltaic cell panel, and the wavelength interval between the center frequency point of the first filtering wave band and the photoluminescence wave crest is a first wavelength interval; the wavelength interval between the central frequency point of the second filtering wave band and the photoluminescence peak is a second wavelength interval; the first wavelength interval is smaller than the second wavelength interval. The image sensor is used for converting incident light into image data, and the processor is electrically connected with the image sensor. The detection equipment can be applied to photoluminescence signal detection.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of photovoltaic power generation, and in particular to a detection device and a detection method for a photovoltaic cell panel. BACKGROUND

[0002] A photovoltaic generation system refers to a power generation system that directly converts solar radiant energy into electric energy by using the photovoltaic effect of a photovoltaic cell panel. The photovoltaic generation system includes multiple photovoltaic cell panels. Due to the fact that the photovoltaic cell panels are exposed to the outdoors for a long time, the photovoltaic cell panels are prone to failure. When the photovoltaic cell panels fail, the photovoltaic generation system will work abnormally. Therefore, it is very important to detect the failure of the photovoltaic cell panels in the photovoltaic generation system.

[0003] Therefore, the related art provides a scheme for detecting failure by using a photoluminescence (PL) signal of a photovoltaic cell panel. The photoluminescence of the photovoltaic cell panel refers to the fact that, under the condition of daytime illumination, the photovoltaic cell panel will be excited by sunlight to generate near-infrared light with a peak at about 1150 nm. When the photovoltaic cell panel fails, the photoluminescence will be affected. Therefore, by detecting the photoluminescence signal, the purpose of detecting the failure of the photovoltaic cell panel can be achieved.

[0004] However, the photoluminescence signal of the photovoltaic cell panel itself is weak, and is mixed with strong sunlight and environmental interference. Therefore, it is difficult to detect the photoluminescence signal. In the related art, the detection of the photoluminescence signal of the photovoltaic cell panel is usually performed in a non-working state before the photovoltaic cell panel is shipped out, and a professional detection device such as a photoluminescence spectrometer is used. The detection conditions and the detection device have high requirements, and it is difficult to apply the detection device to the photovoltaic cell panel in the photovoltaic generation system that has been laid out. SUMMARY

[0005] Embodiments of the present application provide a detection device and a detection method for a photovoltaic cell panel, which are used to improve the problem that it is difficult to detect the photoluminescence signal of the photovoltaic cell panel.

[0006] To achieve the above object, embodiments of the present application adopt the following technical solutions:

[0007] In a first aspect, the embodiments of the present application provide a detection device for a photovoltaic cell panel. The detection device includes a lens, an adjustable light filter, an image sensor, and a processor. The lens and the adjustable light filter are arranged on the light-incoming side of the image sensor. The lens is used to converge light in a target detection area onto the image sensor, and the adjustable light filter is used to filter the light converged by the lens onto the image sensor.

[0008] The adjustable light filtering device has switchable first and second light filtering wavebands; the first light filtering waveband contains a photoluminescence peak of the photovoltaic panel, and a center frequency point of the first light filtering waveband is spaced from a wavelength of the photoluminescence peak by a first wavelength interval; a center frequency point of the second light filtering waveband is spaced from the wavelength of the photoluminescence peak by a second wavelength interval; the first wavelength interval is smaller than the second wavelength interval.

[0009] The image sensor is configured to convert incident light of the first light filtering waveband into first image data and convert incident light of the second light filtering waveband into second image data.

[0010] The processor is electrically connected to the image sensor and is configured to form a photoluminescence detection image according to the first image data and the second image data, or send the first image data and the second image data to a target device.

[0011] In the detection device provided in the embodiments of the present application, the adjustable light filtering device has switchable first and second light filtering wavebands, and by switching the light filtering wavebands of the adjustable light filtering device, the image sensor can convert light of the first light filtering waveband in a target detection region into first image data and convert light of the second light filtering waveband in the target detection region into second image data.

[0012] By designing the first and second light filtering wavebands, the photoluminescence signal in the first and second image data obtained has a large difference, but the environmental signal has little difference. Based on the above relationship between the first and second image data, by simply processing the first and second image data, image data containing only the photoluminescence signal can be obtained, for example, by subtracting the first image data from the second image data, so as to realize the purpose of imaging only the photoluminescence signal and form a photoluminescence detection image corresponding to the photoluminescence signal.

[0013] As can be seen from the above description, when the detection device provided in the embodiments of the present application is used to detect the photovoltaic panel, the detection difficulty of the photoluminescence signal can be reduced, the requirements on the detection environment and the detection device can be reduced, and thus the photovoltaic panel in the photovoltaic power generation system that has been laid out can be detected.

[0014] In addition, in the detection device provided in the embodiments of the present application, the switching of the light filtering wavebands is realized by controlling the adjustable light filtering device, without the need to replace the light filter, and the switching is simple and easy to realize, and is conducive to realizing high-speed switching.

[0015] In some embodiments, the adjustable light filtering device comprises an electrochromic filter and a control power supply, the electrochromic filter comprising a first transparent substrate, a first transparent electrode, an electrochromic filter layer, an electrolyte layer, an ion storage layer, a second transparent electrode and a second transparent substrate arranged in a stack.

[0016] The control power supply is electrically connected with the first transparent electrode and the second transparent electrode respectively and is configured to output a first voltage signal and a second voltage signal to the electrochromic filter; under the action of the first voltage signal, the filtering waveband of the electrochromic filter is a first filtering waveband; under the action of the second voltage signal, the filtering waveband of the electrochromic filter is a second filtering waveband.

[0017] In the detection device provided in the embodiments of the present application, the adjustable light filtering device can adopt an electrochromic filter, the electrochromic filter can realize switching of the filtering waveband under the control of different voltage signals, and has advantages of fast, accurate and stable switching. Moreover, the electrochromic filter is electrically controlled and switching, and has a relatively light and thin size, and is easy to be integrated in other structures of the detection device, for example, in a lens.

[0018] In some embodiments, the control power supply comprises a power supply, a storage capacitor, a first control switch and a second control switch; the two ends of the storage capacitor are electrically connected with the two ends of the power supply respectively, and the two ends of the storage capacitor are also electrically connected with the first transparent electrode and the second transparent electrode respectively; the first control switch is arranged between the power supply and the storage capacitor and is used to control the on-off of the power supply and the storage capacitor; the second control switch is arranged between the storage capacitor and the electrochromic filter and is used to control the on-off of the storage capacitor and the electrochromic filter.

[0019] In this way, the control power supply can provide a stable voltage signal for the electrochromic filter, which is conducive to ensuring the performance of the electrochromic filter.

[0020] In some embodiments, the material of the electrochromic filter layer is tungsten trioxide, and the thickness is 500nm to 600nm. In this way, the requirements of the detection device on the first filtering waveband and the second filtering waveband can be met, and the tungsten trioxide is an inorganic electrochromic material, the process of manufacturing the electrochromic filter by using the tungsten trioxide is relatively simple, has a high yield, and is easy to realize light and thin design.

[0021] In some embodiments, the lens comprises a lens barrel, the lens barrel has a lens barrel cavity through along the optical axis of the lens; the lens further comprises two or more lens pieces arranged along the optical axis of the lens in the lens barrel cavity.

[0022] The electrochromic filter is arranged in the lens barrel cavity and located between any adjacent lens pieces, or located on the side close to the image sensor relative to all lens pieces along the optical axis of the lens, or located on the side away from the image sensor relative to all lens pieces along the optical axis of the lens.

[0023] In the detection device provided by the embodiment of the present application, the electrochromic filter can be integrated in the lens, and the setting position is flexible.

[0024] In some embodiments, the adjustable light filtering device comprises an interference filter and a driving device for driving the interference filter to rotate around an axis perpendicular to the optical axis of the lens; the interference filter has a first state and a second state under the driving of the driving device.

[0025] For incident light propagating along the optical axis of the lens, the interference filter has a first filtering wavelength range in the first state and a second filtering wavelength range in the second state.

[0026] In the detection device provided by the embodiment of the present application, the driving device drives the interference filter to rotate to change the incident angle of the incident light, thereby achieving the purpose of switching the filtering wavelength range; such design has the advantages of simple structure and easy implementation.

[0027] In some embodiments, the lens comprises a lens barrel having a barrel cavity through along the optical axis of the lens; the lens further comprises two or more lenses arranged along the optical axis of the lens in the barrel cavity; the interference filter is rotatably arranged in the barrel cavity around the axis.

[0028] The interference filter is located between any adjacent lenses; or, located on the side close to the image sensor relative to all lenses along the optical axis of the lens; or, located on the side away from the image sensor relative to all lenses along the optical axis of the lens.

[0029] In the detection device provided by the embodiment of the present application, the interference filter can be integrated in the lens, and the setting position is flexible.

[0030] In some embodiments, the driving device comprises a first adsorption structure and a second adsorption structure arranged on both sides of the interference filter, and further comprises a first electromagnetic device and a second electromagnetic device arranged on the lens barrel.

[0031] The first electromagnetic device is located outside the first adsorption structure, and the first electromagnetic device generates a magnetic force on the first adsorption structure after being energized; the second electromagnetic device is located outside the second adsorption structure, and the second electromagnetic device generates a magnetic force on the second adsorption structure after being energized.

[0032] In the detection device provided by the embodiment of the present application, the driving device drives the interference filter to rotate by magnetic attraction, which has the advantages of simple structure, small space occupation, fast response speed, etc.

[0033] In some embodiments, the driving device comprises a linear slider and a rotating structure, the linear slider is slidably arranged on the lens barrel along the lens optical axis and has a clamping groove facing the interference filter; the clamping groove is clamped at the end of the interference filter.

[0034] The rotating structure is rotatably arranged on the lens barrel around the lens optical axis, and the rotating structure drives the linear slider to move along the lens optical axis during rotation around the lens optical axis.

[0035] In the detection device provided in the embodiments of the present application, the driving device drives the interference filter to rotate through the cooperation of the linear slider and the rotating structure, which can adapt to the scene of manually operating and electrically driving the interference filter to rotate to switch the filter wavelength band.

[0036] In some embodiments, the adjustable filter device is a liquid crystal adjustable filter device, an acousto-optic adjustable filter device, or a filter wheel.

[0037] In the detection device provided in the embodiments of the present application, the adjustable filter device can also use a variety of different types of filter wavelength band adjustable devices, and the detection devices with different adjustable filter devices can all reduce the detection difficulty of the photoluminescence signal through the same working process and working principle when detecting the photovoltaic cell panel.

[0038] In some embodiments, the wavelength width of the first filter wavelength band and the second filter wavelength band is equal. In this way, the similarity of the environmental signals in the first image data and the second image data is higher, so that the environmental signal subtraction is simpler and more accurate.

[0039] In some embodiments, the first wavelength interval is less than 3nm, and the wavelength width of the first filter wavelength band is not more than 20nm. In this way, on the one hand, by limiting the first wavelength interval, the center frequency point of the first filter wavelength band can be located at a position close to or even coinciding with the photoluminescence peak, so that more photoluminescence signals can be filtered out and imaged. In this case, the first image data contains most of the photoluminescence signals. On the other hand, by limiting the wavelength width of the first filter wavelength band, the introduction of more environmental signals due to the excessively wide first filter wavelength band can be avoided, so that the proportion of the photoluminescence signal in the total signal is small. As can be seen, by using the above-mentioned first filter wavelength band, the first image data has more photoluminescence signals, and the proportion of the photoluminescence signal is high; thereby the efficiency and accuracy of detection are improved.

[0040] In some embodiments, the second wavelength interval is greater than or equal to 5 nm and less than or equal to 70 nm. In this way, on the one hand, the second filter band is far away from the photoluminescence peak, so that less photoluminescence signal is filtered out and imaged. In this case, the second image data contains less photoluminescence signal. Therefore, when detecting the photovoltaic panel by the first image data and the second image data, more and cleaner photoluminescence signals can be obtained, which is conducive to improving the efficiency and accuracy of detection. On the other hand, the difference between the environmental signals in the first image data and the second image data can be minimized, which is more conducive to improving the accuracy of the obtained photoluminescence detection image, and thus improving the accuracy of fault detection by the photoluminescence detection image.

[0041] In some embodiments, the photoluminescence peak is 1150 nm, the first filter band is 1145 nm to 1155 nm, and the second filter band is 1135 nm to 1145 nm. In this way, on the one hand, the first image data obtained by the first filter band can contain the main photoluminescence signal, and on the other hand, the similarity of the environmental signals in the first image data and the second image data can be higher, so that the environmental signal subtraction is simpler and more accurate.

[0042] In some embodiments, the detection device further comprises an irradiance device for detecting an irradiance value and sending the irradiance value to the processor or the target device. The irradiance value obtained by the irradiance device can adjust the gray threshold of the photoluminescence detection image, which is conducive to the targeted optimization of each photoluminescence detection image, and improves the problem that the irradiance is different due to factors such as weather, time and location, thereby affecting the detection result.

[0043] In some embodiments, the detection device further comprises a fill light for generating an illumination beam, and the illumination beam is near-infrared light. In this way, the detection device can be provided with fill light illumination in the case of insufficient light, so that the problem of weak photoluminescence signal caused by insufficient light and thus the difficulty of photoluminescence signal detection can be improved. In the embodiment with the irradiance device, the processor can control the fill light to work based on the irradiance value obtained by the irradiance device. In addition, by setting the fill light, the requirement for detection time can be relaxed.

[0044] In a second aspect, the embodiments of the present application also provide a detection method of a photovoltaic panel, which comprises:

[0045] Converting the light in the first band and the second band in the target detection area into first image data and second image data, respectively.

[0046] Subtracting the first image data and the second image data to obtain a photoluminescence detection image.

[0047] The first waveband contains a photoluminescence peak of the photovoltaic panel, and the second waveband does not contain a photoluminescence peak.

[0048] In the above detection method, the light in the first filter waveband in the target detection area is converted into first image data, and the light in the second filter waveband in the target detection area is converted into second image data. Through the design of the first filter waveband and the second filter waveband, most of the photoluminescence signals of the photovoltaic panel can be concentrated in the first image data. Since the environmental signals are wide-spectrum signals, the difference between the environmental signals in the first image data and the environmental signals in the second image data is small.

[0049] Based on the above relationship between the first image data and the second image data, by subtracting the first image data from the second image data, image data containing only photoluminescence signals can be obtained, thereby achieving the purpose of imaging only photoluminescence signals and forming a photoluminescence detection image corresponding to the photoluminescence signals.

[0050] As can be seen from the above description, when the above detection method is used to detect the photovoltaic panel, the detection difficulty of the photoluminescence signals can be reduced, the requirements for the detection environment and the detection equipment can be reduced, and thus the photoluminescence signal detection of the photovoltaic panel in the photovoltaic power generation system that has been laid out can be adapted to the scene.

[0051] In some embodiments, before the first image data and the second image data are subtracted to obtain the photoluminescence detection image, the method further includes:

[0052] The first image data and the second image data are intensity compensated; wherein the intensity compensation is used to compensate for the difference between the environmental signals in the first image data and the second image data.

[0053] In this way, the difference between the environmental signals in the two can be reduced or even eliminated, thereby more favorably improving the accuracy of photoluminescence signal detection and improving the accuracy of fault detection through photoluminescence signals.

[0054] In some embodiments, after the first image data and the second image data are subtracted to obtain the photoluminescence detection image, the method further includes:

[0055] The gray threshold of the photoluminescence detection image is adjusted according to the irradiance.

[0056] In this way, it is favorable to improve the problem that the irradiance is different due to factors such as weather, time, and location, thereby affecting the detection result.

[0057] In some embodiments, the light supplement lamp supplements light to the target detection area when the irradiance is lower than a set value. In this way, the problem of different irradiance due to weather, time, location and other factors, which affects the detection result, can be improved by light supplement.

[0058] In some embodiments, the wavelength width of the first wave band and the second wave band is equal. In this way, the similarity of the environmental signals in the first image data and the second image data can be higher, so that the environmental signal subtraction is simpler and more accurate.

[0059] In some embodiments, the first wavelength interval is less than 3nm, and the wavelength width of the first wave band is not more than 20nm. In this way, on the one hand, by limiting the first wavelength interval, the center frequency point of the first wave band can be located close to or even coincide with the photoluminescence peak, in which case the first image data contains most of the photoluminescence signal. On the other hand, by limiting the wavelength width of the first wave band, the problem of too wide first wave band introducing more environmental signals and resulting in a small proportion of photoluminescence signal in the total signal can be avoided. As can be seen, the first wave band with the above design can have more photoluminescence signal in the first image data, and the proportion of photoluminescence signal is high; thus, it is beneficial to improve the efficiency and accuracy of detection.

[0060] In some embodiments, the second wavelength interval is greater than or equal to 5nm and less than or equal to 70nm. In this way, on the one hand, the second wave band can be far away from the photoluminescence peak, in which case the second image data contains less photoluminescence signal. Thus, when detecting the photovoltaic panel by the first image data and the second image data, more and cleaner photoluminescence signal can be obtained; thus, it is beneficial to improve the efficiency and accuracy of detection. On the other hand, the difference between the environmental signals in the first image data and the second image data can be minimized, thus it is more beneficial to improve the accuracy of the obtained photoluminescence detection image, and further improve the accuracy of fault detection by the photoluminescence detection image.

[0061] In some embodiments, the photoluminescence peak is 1150nm, the first wave band is 1145nm to 1155nm, and the second wave band is 1135nm to 1145nm. In this way, on the one hand, the first image data obtained by the first wave band can contain the main photoluminescence signal, and on the other hand, the similarity of the environmental signals in the first image data and the second image data can be higher, so that the environmental signal subtraction is simpler and more accurate.

[0062] In a third aspect, the embodiments of the present application further provide a detection method of a photovoltaic panel, wherein the photovoltaic panel system comprises a photovoltaic management system, an inverter and a plurality of photovoltaic strings; each photovoltaic string comprises a plurality of photovoltaic panels, the plurality of photovoltaic strings are connected to the inverter, the inverter is connected to the photovoltaic management system; the photovoltaic management system comprises a current-voltage monitoring system.

[0063] The detection method comprises:

[0064] controlling the inverter to reduce the current of the photovoltaic string to be detected;

[0065] detecting the photovoltaic string to be detected by using the detection device of any one of the first aspect embodiments to form a photoluminescence detection image.

[0066] locating the fault position based on the photoluminescence detection image.

[0067] In some embodiments, the photovoltaic string to be detected is an abnormal photovoltaic string found by the current-voltage monitoring system.

[0068] In the detection method described above, by cooperating the detection device of the first aspect embodiments with the current-voltage monitoring system (IV system), higher positioning accuracy, more accurate fault identification and comprehensive detection can be achieved. BRIEF DESCRIPTION OF DRAWINGS

[0069] Figure 1 A schematic diagram of a photovoltaic power generation system provided by the related art;

[0070] Figure 2 A structural schematic diagram of a detection device of a photovoltaic panel provided by the embodiments of the present application;

[0071] Figure 3 A relationship diagram of an environmental signal and a photoluminescence signal in a target detection area provided by the embodiments of the present application;

[0072] Figure 4 A relationship diagram of an environmental signal and a photoluminescence signal in a first filter waveband provided by the embodiments of the present application;

[0073] Figure 5 A relationship diagram of an environmental signal and a photoluminescence signal in a second filter waveband provided by the embodiments of the present application;

[0074] Figure 6 A structural schematic diagram of another detection device of a photovoltaic panel provided by the embodiments of the present application;

[0075] Figure 7 A structural schematic diagram of an adjustable filter device provided by the embodiments of the present application;

[0076] Figure 8 This is a schematic diagram showing the installation of the electrochromic filter provided in the embodiment of this application in a detection device;

[0077] Figure 9 A schematic diagram of the structure of another photovoltaic panel testing device provided in an embodiment of this application;

[0078] Figure 10 A diagram showing the relationship between the filtering band and the incident angle of an interference filter provided in an embodiment of this application;

[0079] Figure 11 A schematic diagram illustrating the interaction between an adjustable filter device and a lens barrel, provided in an embodiment of this application;

[0080] Figure 12 A schematic diagram illustrating the interaction between another adjustable filter device and a lens barrel, provided in an embodiment of this application;

[0081] Figure 13 A schematic diagram of the structure of another photovoltaic panel testing device provided in this application embodiment;

[0082] Figure 14 A schematic diagram of the structure of another photovoltaic panel testing device provided in this application embodiment;

[0083] Figure 15 A flowchart illustrating a method for testing a photovoltaic panel, as provided in an embodiment of this application;

[0084] Figure 16 This is a flowchart of a testing method for a photovoltaic power generation system provided in an embodiment of this application. Detailed Implementation

[0085] A photovoltaic (PV) power generation system is a power generation system that uses the photovoltaic effect of photovoltaic panels to directly convert solar radiation energy into electrical energy. For example... Figure 1 As shown, the photovoltaic power generation system 100 provided by related technologies includes a photovoltaic management system 130, an inverter 120, and multiple photovoltaic strings 110. Each photovoltaic string 110 includes multiple photovoltaic panels 101, and each photovoltaic panel 101 includes multiple solar cell units. The multiple photovoltaic strings 110 are connected to the inverter 120, and the inverter 120 is connected to the photovoltaic management system 130. The photovoltaic management system 130 is used to manage and monitor the photovoltaic power generation system 100.

[0086] In the photovoltaic power generation system 100, due to the long-term exposure of the photovoltaic panel 101 to the outdoor environment and the like, faults are prone to occur. When the photovoltaic panel 101 fails, it will cause the photovoltaic power generation system 100 to work abnormally. Therefore, it is very important to detect the fault of the photovoltaic panel 101 in the photovoltaic power generation system 100 for the normal operation of the photovoltaic power generation system 100.

[0087] Based on this, the related technology provides a scheme for detecting faults through the photoluminescence (PL) signal of the photovoltaic panel 101. The photoluminescence of the photovoltaic panel 101 refers to that under the condition of daytime light, the photovoltaic panel 101 will be excited by sunlight to generate near-infrared light with a peak at about 1150nm. When the photovoltaic panel 101 fails, it will affect the photoluminescence, so by detecting the photoluminescence signal, the purpose of detecting the fault of the photovoltaic panel 101 can be achieved.

[0088] However, since the photoluminescence signal of the photovoltaic panel 101 itself is weak, and is mixed with strong sunlight and environmental interference, the detection of the photoluminescence signal is relatively difficult. In the related technology, the detection of the photoluminescence signal of the photovoltaic panel 101 can usually only be realized in the non-working state before leaving the factory by using professional detection equipment such as a photoluminescence spectrometer; the requirements for the detection conditions and the detection equipment are high, and it is difficult to apply to the detection of the photovoltaic panel 101 in the photovoltaic power generation system 100 which has been laid out.

[0089] Based on this, the embodiment of the present application provides a detection device for a photovoltaic panel to improve the above problems.

[0090] The technical solutions in the embodiments of the present application will be described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all embodiments.

[0091] In the embodiments of the present application, the terms "first", "second", and the like are only used for description convenience, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first", "second", and the like can explicitly or implicitly include one or more features. In the description of the present application, unless otherwise specified, the meaning of "multiple" is two or more.

[0092] In the embodiments of the present application, "up", "down", "left", and "right" are not limited to the relative positions of the components shown in the drawings, and it should be understood that these directional terms can be relative concepts, which are used for relative description and clarification, and can change accordingly according to the change of the position of the components shown in the drawings.

[0093] In the embodiments of the present application, unless otherwise required by the context, throughout the specification and claims, the term "comprising" is to be interpreted as open, inclusive, meaning that "including but not limited to". In the description of the specification, the terms "one embodiment", "some embodiments", "exemplary embodiments", "exemplary", or "some examples" are intended to mean that the particular feature, structure, material, or characteristic being described in connection with such embodiment or example includes at least one embodiment or example of the present application. The appearance of the above terms in various places in the specification are not necessarily all referring to the same embodiment or example. Also, the particular features, structures, materials, or characteristics can be combined in any suitable manner in one or more embodiments or examples.

[0094] As used herein, "about", "approximately", or "around" includes the recited value and the average value within an acceptable range of deviation from the particular value, as determined by one of ordinary skill in the art taking into account the measurement being discussed and the error associated with the measurement of the particular quantity (i.e., the limitations of the measurement system).

[0095] As used herein, "parallel", "perpendicular", "equal" includes the recited condition and conditions that approximate the recited condition, the approximation being within an acceptable range of deviation, as determined by one of ordinary skill in the art taking into account the measurement being discussed and the error associated with the measurement of the particular quantity (i.e., the limitations of the measurement system). For example, "parallel" includes absolute parallel and near parallel, where near parallel can have an acceptable range of deviation of, for example, within 5°; "perpendicular" includes absolute perpendicular and near perpendicular, where near perpendicular can also have an acceptable range of deviation of, for example, within 5°. "Equal" includes absolute equality and near equality, where near equality can have an acceptable range of deviation of, for example, a difference between the two that is less than or equal to 5% of either.

[0096] It should be understood that when a layer or element is referred to as being "on" another layer or substrate, it can be directly on the other layer or substrate, or intervening layers can also be present.

[0097] The exemplary embodiments are described in the application examples with reference to cross-sectional views and / or plan views and / or equivalent circuit diagrams as idealized exemplary drawings. In the drawings, the thickness of layers and regions are exaggerated for clarity. Accordingly, variations from the shapes of the illustrations as a result, for example, of manufacturing techniques and / or tolerances, are to be expected. Thus, the exemplary embodiments should not be construed as limited to the precise shapes of regions illustrated herein but are to include deviations in shapes that result from, for example, manufacturing. For example, an etched region illustrated as a rectangle will typically have curved distal terminations. Thus, the regions illustrated in the drawings are schematic and their shapes are not intended to illustrate the precise shape of a region of a device and are not intended to limit the scope of the exemplary embodiments.

[0098] The application examples provide a detection device of a photovoltaic cell panel, which can be referred to as a detection device herein. The detection device is used for detecting a photoluminescence signal of a photovoltaic cell panel, so as to achieve the purpose of photovoltaic cell panel fault detection. Figure 2 As shown in the figure, the detection device 1 comprises an image sensor 3, a lens 5, an adjustable light filtering device 4 and a processor 2.

[0099] The image sensor 3 is a photoelectric conversion device, which can convert incident light into image data, so as to realize the imaging function of the incident light. The image sensor 3 can be a complementary metal oxide semiconductor (CMOS) image sensor or a charge coupled device (CCD) image sensor, etc. The detection device 1 provided in the application examples is not limited to the type of image sensor 3.

[0100] Please continue to refer to Figure 2 The lens 5 is arranged on the light-incident side of the image sensor 3, and is used for converging the light in the target detection area to the image sensor 3, that is, the lens 5 is used for converting the light in the target detection area into incident light incident to the image sensor 3. Through the lens 5, the image sensor 3 can convert the light in the target detection area into image data, so as to realize the imaging function of the target detection area. The lens 5 comprises two or more lenses 51 arranged along the lens optical axis L, and the detection device 1 provided in the application examples is not limited to the number of lenses 51 in the lens 5.

[0101] The adjustable light filtering device 4 is also arranged on the light-incident side of the image sensor 3, and can be arranged between any adjacent lenses 51 in the lens 5, or can be arranged on the side away from the image sensor 3 along the lens optical axis L relative to the lens 5, or can be arranged on the side close to the image sensor 3 along the lens optical axis L relative to the lens 5.

[0102] The adjustable light filtering device 4 is a light filtering device with adjustable light filtering waveband, and has a first state and a second state which can be controlled to switch. The light filtering waveband of the adjustable light filtering device 4 in the first state is a first light filtering waveband, and the light filtering waveband in the second state is a second light filtering waveband. The first state and the second state can be switched, and the switching mode can be electrically controlled switching or manual switching.

[0103] As shown in the example of Figure 2 The adjustable light filtering device 4 can be electrically connected with the processor 2, and the processor 2 can send a first control signal and a second control signal to the adjustable light filtering device 4. In response to the first control signal sent by the processor 2, the adjustable light filtering device 4 is in the first state; in response to the second control signal sent by the processor 2, the adjustable light filtering device 4 is in the second state. As can be seen, by sending different control signals to the adjustable light filtering device 4 through the processor 2, the light filtering waveband of the adjustable light filtering device 4 can be switched between the first light filtering waveband and the second light filtering waveband.

[0104] In the detection device 1 provided in the embodiments of the present application, the light filtering function of the adjustable light filtering device 4 can be used to filter the light rays converging on the image sensor 3 through the lens 5, so that the light rays incident on the image sensor 3 are the light rays in the target detection area which are in the light filtering waveband; thereby the image sensor 3 can convert the light rays in the light filtering waveband in the target detection area into image data, achieving the purpose of imaging the light rays in the light filtering waveband in the target detection area. Moreover, since the light filtering waveband of the adjustable light filtering device 4 is adjustable, by changing the light filtering waveband of the adjustable light filtering device 4, the image sensor 3 can convert the light rays in different light filtering wavebands in the target detection area into image data respectively, achieving the purpose of imaging the light rays in different light filtering wavebands in the target detection area respectively.

[0105] For ease of description, the light rays in the first light filtering waveband in the target detection area are referred to as first light rays, and the light rays in the second light filtering waveband in the target detection area are referred to as second light rays. The image data formed by the image sensor 3 on the first light rays is referred to as first image data, and the image data formed by the image sensor 3 on the second light rays is referred to as second image data.

[0106] When the detection device 1 provided in the embodiments of the present application is used to detect the photovoltaic cell panel, by controlling the adjustable light filtering device 4 to be in the first state, the first light rays in the target detection area can be incident on the image sensor 3; in this case, the image sensor 3 can photoelectrically convert the first light rays to form the first image data, achieving the purpose of imaging the light rays in the first light filtering waveband in the target detection area. The first image data contains the photoluminescence signal and the environmental signal in the first light filtering waveband.

[0107] By controlling the adjustable light filtering device 4 to be in the second state, the second light in the target detection area can be incident to the image sensor 3; in this case, the image sensor 3 can perform photoelectric conversion on the second light to form second image data, so as to achieve the purpose of imaging the light in the second filtering waveband in the target detection area. The second image data contains the photoluminescence signal and the environmental signal in the second filtering waveband.

[0108] In the detection device 1 provided in the embodiments of the present application, through the design of the adjustable light filtering device 4, the first filtering waveband contains the photoluminescence peak (for example, 1150 nm) of the photovoltaic cell panel, and the wavelength interval between the center frequency point of the first filtering waveband and the photoluminescence peak (for example, 1150 nm) is a first wavelength interval. The wavelength interval between the center frequency point of the second filtering waveband and the photoluminescence peak (for example, 1150 nm) is a second wavelength interval; the first wavelength interval is smaller than the second wavelength interval. That is, compared with the second filtering waveband, the center frequency point of the first filtering waveband is closer to the photoluminescence peak (for example, 1150 nm).

[0109] Please refer to Figures 3 to 5 Since the photoluminescence signal of the photovoltaic cell panel is concentrated near the photoluminescence peak 1150 nm, and generally mainly distributed in a waveband with a wavelength width of 10 nm, that is, the waveband of 1145 nm to 1150 nm. At different wavelengths near the photoluminescence peak 1150 nm, the photoluminescence signal changes greatly. When the interval from the photoluminescence peak is greater than or equal to 5 nm, the photoluminescence signal will be greatly attenuated. Since the environmental signal is a wide-band signal, it has a strong signal in a very wide waveband, and the change is small. Therefore, when the first filtering waveband and the second filtering waveband adopt the above design, in the obtained first image data and second image data, the photoluminescence signal has a large difference, but the environmental signal has a small difference.

[0110] Please refer to Figure 2 The processor 2 is electrically connected with the image sensor 3, the image sensor 3 sends the image data (for example, the first image data and the second image data) formed after photoelectric conversion to the processor 2, and the processor 2 is used for receiving and processing the image data formed by the image sensor 3. Based on the above relationship between the first image data and the second image data, after obtaining the first image data and the second image data, the processor 2 can obtain image data containing only the photoluminescence signal by processing the first image data and the second image data, for example, subtracting the first image data from the second image data, so as to achieve the purpose of imaging only the photoluminescence signal, and form a photoluminescence detection image corresponding to the photoluminescence signal.

[0111] In some embodiments, the first wavelength interval is less than 3 nm, and the first filter wavelength band has a wavelength width of no more than 20 nm. For example, the photoluminescence peak is at 1150 nm, and the first filter wavelength band is 1145-1155 nm (centered at 1150 nm, first wavelength interval is 0 nm, and wavelength width is 10 nm), 1143-1153 nm (centered at 1148 nm, first wavelength interval is 2 nm, and wavelength width is 10 nm), or 1140-1160 nm (centered at 1150 nm, first wavelength interval is 0 nm, and wavelength width is 20 nm), and the like.

[0112] With the above design, on one hand, by limiting the first wavelength interval, the center of the first filter wavelength band can be located close to, or even coincides with, the photoluminescence peak, so that more photoluminescence signals can be filtered out and imaged. In this case, the first image data contains most of the photoluminescence signals. On the other hand, by limiting the wavelength width of the first filter wavelength band, more ambient signals can be avoided due to the excessively wide first filter wavelength band, so that the proportion of photoluminescence signals in the total signals is small. As can be seen, by using the above design of the first filter wavelength band, the first image data can contain more photoluminescence signals, and the proportion of photoluminescence signals is high, so that the efficiency and accuracy of detection can be improved.

[0113] In some embodiments, the second wavelength interval is greater than or equal to 5 nm. For example, the second wavelength interval can be 5-10 nm, 10-20 nm, 20-40 nm, 40-60 nm, or 60-80 nm, and the like; or the second wavelength interval can be 5 nm, 10 nm, 15 nm, 20 nm, 30 nm, 40 nm, 50 nm, 60 nm, 70 nm, or 80 nm, and the like. With the above design, the second filter wavelength band can be far away from the photoluminescence peak, so that fewer photoluminescence signals can be filtered out and imaged. In this case, the second image data contains fewer photoluminescence signals. Therefore, when the photovoltaic panel is detected by using the first image data and the second image data, more and cleaner photoluminescence signals can be obtained, so that the efficiency and accuracy of detection can be improved.

[0114] In the above scheme, although the change of the environmental signal in the first filter wavelength band and the second filter wavelength band is small, there is still some difference. Therefore, in some embodiments, the second wavelength interval is limited to no more than 80 nm. Exemplarily, the second wavelength interval can be 5 nm, 10 nm, 15 nm, 20 nm, 30 nm, 40 nm, 50 nm, 60 nm, 70 nm, or 80 nm, etc. In this way, the difference of the environmental signal in the first image data and the second image data can be reduced as much as possible, thereby more favorably improving the accuracy of the obtained photoluminescence detection image, and further improving the accuracy of fault detection through the photoluminescence detection image.

[0115] In some embodiments, the wavelength width of the second filter wavelength band is equal to the wavelength width of the first filter wavelength band, for example, both are 10 nm or 20 nm. In this way, on the one hand, the first image data obtained through the first filter wavelength band can contain the main photoluminescence signal, and on the other hand, the similarity of the environmental signal in the first image data and the second image data can be higher, thereby making it simpler and more accurate when subtracting the environmental signal.

[0116] Exemplarily, the photoluminescence peak is 1150 nm, and the second filter wavelength band is 1135 nm to 1145 nm (the center frequency point is 1140 nm, the second wavelength interval is 10 nm, and the wavelength width is 10 nm), 1155 nm to 1165 nm (the center frequency point is 1160 nm, the second wavelength interval is 10 nm, and the wavelength width is 10 nm), 1125 nm to 1135 nm (the center frequency point is 1130 nm, the second wavelength interval is 20 nm, and the wavelength width is 10 nm), or 1120 nm to 1140 nm (the center frequency point is 1130 nm, the second wavelength interval is 20 nm, and the wavelength width is 20 nm), etc.

[0117] In addition, in some embodiments, after receiving the first image data and the second image data, the processor 2 can perform intensity compensation on the first image data and the second image data; the intensity compensation is used to compensate for the difference of the environmental signal in the first image data and the second image data, so as to reduce or even eliminate the difference of the environmental signal in the two, thereby more favorably improving the accuracy of the obtained photoluminescence detection image, and further improving the accuracy of fault detection through the photoluminescence detection image.

[0118] The detection equipment 1 provided in the embodiments of the present application can form a photoluminescence detection image through detection of a photoluminescence signal, thereby achieving fault detection of the photovoltaic panel. With such a design, compared with the scheme in the related art that uses voltage and current information (for example, an IV curve) of the photovoltaic string 110 to determine whether a fault occurs, the fault detection using the detection equipment 1 provided in the embodiments of the present application can at least locate the fault to a specific photovoltaic panel, and the fault location is more accurate.

[0119] Compared with the scheme in the related art that uses a thermal infrared camera to capture an image and determines whether a fault occurs in the photovoltaic panel based on a heating abnormality, the fault detection using the detection equipment 1 provided in the embodiments of the present application can identify more and more subtle faults, for example, a hidden crack, and the fault identification is more accurate and comprehensive.

[0120] Compared with the scheme in the related art that uses electroluminescent (EL) technology to detect faults in the photovoltaic panel, the fault detection using the detection equipment 1 provided in the embodiments of the present application can not need to perform reverse current on the photovoltaic panel, the detection process is simpler, the safety is higher, and the fault detection of the photovoltaic panel can be achieved during the operation of the photovoltaic power generation system 100; and the requirement for the detection condition is lower.

[0121] In the detection equipment 1 provided in the embodiments of the present application, through the design of the first filter waveband and the second filter waveband, when the detection equipment 1 is used for fault detection of the photovoltaic panel, the light in the first filter waveband and the second filter waveband is imaged respectively, and then simple processing is performed on the two images to obtain image data containing only the photoluminescence signal; thereby the detection difficulty of the photoluminescence signal can be reduced, the requirement for the detection environment and the detection equipment 1 is reduced, and thus the detection of the photovoltaic panel in the photovoltaic power generation system 100 that has been laid out can be adapted to the scene.

[0122] In the detection equipment 1 provided in the embodiments of the present application, the switching of the filter waveband is achieved through the control of the adjustable filter device 4, without the need to replace the filter, the switching is simple and easy to implement, and is conducive to high-speed switching. In the case that the filter waveband of the adjustable filter device 4 can be switched at a high speed, on the one hand, the time interval of the first image data and the second image data can be shortened, so that the difference between the environmental signals in the first image data and the second image data is smaller, thereby the speed of obtaining the photoluminescence signal through the first image data and the second image data is faster, and the result is more accurate; on the other hand, the overall detection speed can be improved, which is conducive to rapid patrol inspection. For example, the detection equipment 1 provided in the embodiments of the present application can be mounted on a drone to perform rapid patrol inspection on the large-scale photovoltaic panel laid out in the photovoltaic power generation system 100.

[0123] In some embodiments, such as Figure 6 As shown, the detection device 1 includes a device body 6, with an image sensor 3 and a processor 2 installed within the device body 6. The lens 5 in the detection device 1 also includes a lens barrel 52, which has a lens barrel cavity 53 with the lens optical axis L as its central axis. The lens 5 is disposed within the lens barrel cavity 53 of the lens barrel 52. The lens 5 is connected to the device body 6 via the lens barrel 52, and the lens barrel 52 and the device body 6 can be detachably connected, thereby enabling the replacement of the lens 5.

[0124] In the design with lens barrel 52, the adjustable filter device 4 can be installed in lens barrel 52, that is, integrated with lens 5. For example... Figure 6 As shown in sections (a), (b) and (c), the adjustable filter device 4 can be disposed between any adjacent lenses 51 in the lens 5, or disposed on the side away from the image sensor 3 (i.e., the device body 6) relative to all lenses 51 along the lens optical axis L, or disposed on the side closer to the image sensor 3 (i.e., the device body 6) relative to all lenses 51 along the lens optical axis L.

[0125] This application also provides another detection device 1, such as... Figure 7 As shown, in this detection device 1, the adjustable filtering device 4 includes an electrochromic filter 41 and a control power supply 42. The electrochromic filter 41 includes a first transparent substrate 411, a first transparent electrode 412, an electrochromic filter layer 413, an electrolyte layer 414, an ion storage layer 415, a second transparent electrode 416, and a second transparent substrate 417, which are stacked together. The first transparent substrate 411 and the second transparent substrate 417 are arranged opposite to each other and are transparent plate-like structures made of transparent materials; for example, they can be glass substrates or transparent plastic substrates. The first transparent electrode 412 and the second transparent electrode 416 are electrodes made of transparent conductive materials, such as indium tin oxide (ITO) electrodes.

[0126] The electrochromic filter layer 413 is made of electrochromic material. The electrochromic material can be an inorganic electrochromic material, such as tungsten trioxide (WO3), or an organic electrochromic material, such as polythiophene and its derivatives, iologens, tetrathiofulvalene, metal phthalocyanine compounds, etc.

[0127] Electrochromic materials undergo electrochemical oxidation-reduction reactions under the action of an external electric field, resulting in stable and reversible changes in the optical properties of the material (such as reflectivity, transmittance, and absorptivity) through the gain and loss of electrons. These changes manifest externally as color changes, or changes in the filtered wavelength.

[0128] The ion storage layer 415 is used to store ions generated by the electrochromic filter layer 413 and release ions required by the electrochromic filter layer 413 when the electrochemical redox reaction of the electrochromic filter layer 413 occurs. The electrolyte layer 414 is used to provide a channel for ion movement between the ion storage layer 415 and the electrochromic filter layer 413.

[0129] As can be known from the above description, in the electrochromic filter 41, by applying different electric fields to the first transparent electrode 412 and the second transparent electrode 416, the filtering waveband of the electrochromic filter layer 413 can be changed, and the function of filtering different filtering wavebands can be realized. In this embodiment, through the design of the electrochromic filter layer 413, the electrochromic filter 41 can have a first state with a first filtering waveband and a second state with a second filtering waveband. The description of the first filtering waveband and the second filtering waveband can be referred to the above, and will not be described here. For example, the electrochromic filter layer 413 in the electrochromic filter 41 can be selected from tungsten trioxide, and the thickness is 500 nm to 600 nm.

[0130] Please continue to refer to Figure 7 The adjustable filtering device 4 further includes a control power supply 42, which is electrically connected with the electrochromic filter 41. The control power supply 42 can apply a first voltage signal and a second voltage signal to the first transparent electrode 412 and the second transparent electrode 416. Under the action of the first voltage signal, the electrochromic filter 41 is in the first state, that is, the filtering waveband is the first filtering waveband; under the action of the second voltage signal, the electrochromic filter 41 is in the second state, that is, the filtering waveband is the second filtering waveband. As can be seen, by controlling the voltage signal applied to the first transparent electrode 412 and the second transparent electrode 416 by the control power supply 42, the switching of the first filtering waveband and the second filtering waveband can be realized.

[0131] In some embodiments, as Figure 7 shown, the control power supply 42 includes a power supply V, a storage capacitor C, a first control switch S1 and a second control switch S2, wherein the two ends of the power supply V are respectively connected with the two ends of the storage capacitor C, and the two ends of the storage capacitor C are also respectively connected with the first transparent electrode 412 and the second transparent electrode 416 in the electrochromic filter 41. The first control switch S1 is arranged between the power supply V and the storage capacitor C, and is used to control the on-off of the control power supply 42 and the storage capacitor C; the second control switch S2 is arranged between the storage capacitor C and the electrochromic filter 41, and is used to control the on-off of the storage capacitor C and the electrochromic filter 41.

[0132] During operation, the first control switch S1 is turned on and the second control switch S2 is turned off; the power supply V charges the storage capacitor C. After charging is complete, the first control switch S1 is turned off. When it is necessary to control the electrochromic filter 41 to switch the filter frequency band, the second control switch S2 is turned on, and the charge stored in the storage capacitor C is applied to the first transparent electrode 412 and the second transparent electrode 416.

[0133] The control power supply 42 designed above can provide a stable voltage for the electrochromic filter 41, which is beneficial to achieving accurate switching of the filter band.

[0134] The detection process, detection principle, and achievable effect of the detection device 1 with electrochromic filter 41 for photoluminescence signals can be referred to the above description, and will not be repeated here.

[0135] In some embodiments, the electrochromic filter 41 is mounted on the lens barrel 52 of the lens 5, i.e., integrated into the lens 5. For example, as... Figure 8 As shown in sections (a), (b), and (c), the electrochromic filter 41 is disposed in the lens barrel cavity 53 of the lens barrel 52. It can be disposed between any adjacent lens elements 51 in the lens 5, or on the side of the lens barrel 5 away from the image sensor 3 (i.e., the device body 6) relative to all lens elements 51 along the lens optical axis L, or on the side of the lens barrel 52 closer to the image sensor 3 (i.e., the device body 6) relative to all lens elements 51 along the lens optical axis L. In this case, the control power supply 42 in the adjustable filter device 4 can be integrated into the lens barrel 52.

[0136] This application embodiment also provides another detection device 1, in which, such as Figure 9 As shown, the adjustable filtering device 4 includes an interference filter 44 and a driving device 43. The interference filter 44 is a filter that uses the principle of light interference for filtering, and is typically composed of multiple thin films. The filtering band of the interference filter 44 is related to the incident angle of the light. When the light is incident at an angle, the optical path difference is smaller compared to normal incidence (perpendicular incidence), causing the center frequency of the filtering band to shift towards shorter wavelengths compared to normal incidence (perpendicular incidence). As the angle of incidence increases, the magnitude of the shift of the center frequency of the filtering band towards shorter wavelengths also increases.

[0137] For example, such as Figure 10As shown, for the interference filter 44 with a center frequency of 1150 nm in the filtering band, when the light is incident normally (perpendicularly), the center frequency of its filtering band is 1150 nm. When the light is incident obliquely, and the angle of oblique incidence is increased in 2° increments from normal incidence, the center frequency of the filtering band of the interference filter 44 gradually shortens. When the angle of oblique incidence increases to 24 degrees, the center frequency of the filtering band shortens to 1115 nm. During the process of the center frequency of the filtering band shortening, the wavelength width of the filtering band remains basically unchanged.

[0138] It can be seen that by controlling the incident angle of light, the filtering band of the interference filter 44 can be adjusted.

[0139] Please continue to refer to this. Figure 9 In this embodiment, the adjustable filtering device 4 further includes a driving device 43, which drives the interference filter 44 to move, such as... Figure 9 As shown in parts (a) and (b), the interference filter 44 has a first state and a second state under the drive of the driving device 43. The angle of the interference filter 44 relative to the optical axis L of the lens is different in the first state and the second state, thereby changing the incident angle of light on the interference filter 44. By designing the interference filter 44 and its position in the first and second states, the filtering band of the interference filter 44 can be the first filtering band when it is in the first state, and the filtering band is the second filtering band when it is in the second state. The description of the first filtering band and the second filtering band can be found above, and will not be repeated here.

[0140] The drive unit 43 in the adjustable filter device 4 can be electrically connected to the processor 2. The processor 2 can send a first control signal and a second control signal to the drive unit 43. In response to the first control signal from the processor 2, the drive unit 43 drives the interference filter 44 to a first state; in response to the second control signal from the processor 2, the drive unit 43 drives the interference filter 44 to a second state. This allows for switching between the first and second filter bands.

[0141] The detection process, detection principle, and achievable effect of the detection device 1 with interference filter 44 for photoluminescence signals can be referred to the above description, and will not be repeated here.

[0142] This application embodiment also provides another detection device 1, which is related to... Figure 9The difference of the shown detection device 1 is that the adjustable filter device 4 is integrated in the lens 5 with the lens barrel 52. Specifically, one end or middle part of the interference filter 44 is rotatably arranged in the lens barrel cavity 53 of the lens barrel 52 around a rotation axis perpendicular to the lens optical axis L, and the driving device 43 is used to drive the interference filter 44 to rotate around the rotation axis, and the interference filter 44 has a first state and a second state during rotation.

[0143] The driving device 43 can adopt any device capable of driving the interference filter 44 to rotate around the rotation axis. For example, in some embodiments, as shown in Figure 11 the driving device 43 includes a first adsorption structure 432 and a second adsorption structure 433 arranged on both sides of the interference filter 44, and a first electromagnetic device 431 and a second electromagnetic device 434 arranged on the lens barrel 52. Among them, the first electromagnetic device 431 is installed on the lens barrel 52 and is located outside the first adsorption structure 432; after the first electromagnetic device 431 is powered on, a magnetic force can be generated on the first adsorption structure 432, thereby driving the interference filter 44 to rotate towards the side where the first electromagnetic device 431 is located. The second electromagnetic device 434 is installed on the lens barrel 52 and is located outside the second adsorption structure 433; after the second electromagnetic device 434 is powered on, a magnetic force can be generated on the second adsorption structure 433, thereby driving the interference filter 44 to rotate towards the side where the second electromagnetic device 434 is located.

[0144] As can be seen from Figure 11 parts (a) and (b) in the middle, by controlling the power-on and power-off of the first electromagnetic device 431 and the second electromagnetic device 434, the purpose of driving the interference filter 44 to rotate in different directions can be achieved, thereby achieving the purpose of switching between the first state and the second state.

[0145] For the adjustable filter device 4 designed as above, the interference filter 44 can be arranged between any adjacent lenses 51 in the lens 5, or can be arranged on the side away from the image sensor 3 (i.e. the device body 6) along the lens optical axis L relative to all lenses 51, or can be arranged on the side close to the image sensor 3 (i.e. the device body 6) along the lens optical axis L relative to all lenses 51.

[0146] For example, in some embodiments, as shown in Figure 12 the driving device 43 includes a linear slider 436 and a rotating structure 435, wherein the linear slider 436 is slidingly installed inside the lens barrel 52 along the lens optical axis L and has a clamping groove with an opening facing the interference filter 44, which can be a V-shaped groove or a U-shaped groove for example. The clamping groove clamps the end of the interference filter 44, and during the sliding of the linear slider 436 along the lens optical axis L, the interference filter 44 can be driven to rotate around the axis by the clamping groove.

[0147] The rotating structure 435 is mounted on the lens barrel 52 and can rotate around the lens optical axis L; the rotating structure 435 cooperates with the linear slider 436 to form a rotating-linear motion conversion mechanism, and the rotating structure 435 can drive the linear slider 436 to move linearly along the lens optical axis L during rotation around the lens optical axis L. For example, the rotating structure 435 and the linear slider 436 are connected through a threaded structure.

[0148] The rotation of the rotating structure 435 can be driven manually or by a motor. As can be seen from the above description, the linear slider 436 and the rotating structure 435 in the driving device 43 can drive the interference filter 44 to rotate around the axis, thereby achieving the purpose of switching between the first state and the second state. Figure 12 As shown in parts (a) and (b) of FIG. 7, the linear slider 436 and the rotating structure 435 in the driving device 43 can drive the interference filter 44 to rotate around the axis, thereby achieving the purpose of switching between the first state and the second state.

[0149] For the adjustable filter device 4 designed as described above, the interference filter 44 can be arranged between any adjacent lenses 51 in the lens 5, or can be arranged on the side of the lens optical axis L away from the image sensor 3 (i.e., the device body 6) relative to all lenses 51, or can be arranged on the side of the lens optical axis L close to the image sensor 3 (i.e., the device body 6) relative to all lenses 51.

[0150] In the detection device 1 provided in the embodiments of the present application, the adjustable filter device 4 can also use a liquid crystal adjustable filter device, an acousto-optic adjustable filter device, or a filter wheel, etc. The detection device 1 with different adjustable filter devices 4 has the same working principle, working process and effects when detecting the photovoltaic panel, which will not be described here.

[0151] The embodiments of the present application also provide a detection device 1, as shown in FIG. 8, which is different from the above-mentioned detection device 1 in that it further comprises an irradiance device 7. The irradiance device 7 is used to detect the irradiance value of the target detection area and send the irradiance value to the processor 2. Figure 13 Based on the irradiance value, the processor 2 can adjust the gray threshold of the photoluminescence detection image, thereby facilitating the targeted optimization of each photoluminescence detection image and improving the problem that different irradiance due to weather, time and location, etc. affects the detection result.

[0152]

[0153] ​The irradiance device 7 can be integrated in the detection device 1 and electrically connected with the processor 2, so that the irradiance value can be directly sent to the processor 2. The irradiance device 7 can also be a separate device, and the irradiance value is sent to the processor 2 through wired or wireless mode. For example, the irradiance device 7 can be arranged in the laying area of the photovoltaic panel, and the irradiance value is sent to the processor 2 through wireless mode. For another example, the irradiance device 7 and the detection device 1 are both mounted on a patrol unmanned aerial vehicle, and the two are connected through a cable.

[0154] The embodiment of the present application also provides a detection device 1, as shown in the figure, which is different from the detection device 1 described above in that the detection device 1 further comprises a light supplementing lamp 8. The light supplementing lamp 8 works under the control of the processor 2, and the light supplementing lamp 8 generates an illumination light beam capable of exciting photoluminescence of the photovoltaic panel when working. The illumination light beam can be near-infrared light. Figure 14

[0155] By arranging the light supplementing lamp 8, the detection device 1 can be provided with light supplementing illumination in the case of insufficient light, so that the problem that the photoluminescence signal is weak due to insufficient light and the detection difficulty of the photoluminescence signal is increased can be improved. In the embodiment with the irradiance device 7, the processor 2 can control the light supplementing lamp 8 to work based on the irradiance value obtained by the irradiance device 7. In addition, by arranging the light supplementing lamp 8, the requirement for the detection time can also be relaxed.

[0156] The light supplementing lamp 8 can be integrated in the detection device 1 or be a separate device. For example, the light supplementing lamp 8 and the detection device 1 are two independent devices, and both are mounted on a patrol unmanned aerial vehicle.

[0157] In the above embodiment, the processor 2 is a general term of devices with processing functions in the detection device 1, and can be one processing device or multiple processing devices. The above processor 2 is used to form a detection image containing a photoluminescence signal by processing the first image data and the second image data, but the embodiment of the present application is not limited thereto. For example, the processor 2 in the detection device 1 can be used to perform preprocessing such as noise reduction and white balance on the first image data and the second image data, and then send the preprocessed first image data and second image data to a target device. That is, the detection device 1 is only used to convert the first filter waveband and the second filter waveband in the target detection area into the first image data and the second image data.

[0158] In some embodiments, the processor 2 can store the first image data and the second image data in the storage device of the detection device 1, and after the detection device 1 completes the detection task, the first image data and the second image data are transmitted to the processing device through the storage device for image processing to form a photoluminescence detection image containing a photoluminescence signal. ​

[0159] In some embodiments, the processor 2 can transmit the first image data and the second image data to a processing device through wired or wireless manner, and the processing device can process the image data to form a photoluminescence detection image containing the photoluminescence signal. Figure 1 ).

[0160] For example, the detection device 1 is mounted on an inspection unmanned aerial vehicle and connected with a data transmission module on the inspection unmanned aerial vehicle. During the flight inspection process of the inspection unmanned aerial vehicle, the detection device 1 sends the first image data and the second image data to the data transmission module on the inspection unmanned aerial vehicle, and the data transmission module transmits the data to a processing device on the ground in real time. The processing device processes the data in real time and presents a photoluminescence detection image.

[0161] The embodiments of the present application also provide a detection method of a photovoltaic panel, as shown in Figure 15 The detection method can include the following steps.

[0162] Step S10: converting the light in the first wave band and the second wave band in the target detection area into first image data and second image data, respectively.

[0163] The first wave band contains a photoluminescence peak (e.g. 1150 nm) of the photovoltaic panel, and the center frequency point of the first wave band is separated from the wavelength of the photoluminescence peak (e.g. 1150 nm) by a first wavelength interval. The center frequency point of the second wave band is separated from the wavelength of the photoluminescence peak (e.g. 1150 nm) by a second wavelength interval; the first wavelength interval is smaller than the second wavelength interval; that is, the center frequency point of the first wave band is closer to the photoluminescence peak (e.g. 1150 nm) than the second wave band. In this way, in the obtained first image data and second image data, the photoluminescence signal has a large difference, but the environmental signal has little difference, so that the image data containing only the photoluminescence signal can be obtained by processing the first image data and the second image data.

[0164] In some embodiments, the first wavelength interval is less than 3 nm, and the wavelength width of the first wave band is not more than 20 nm. For example, the photoluminescence peak is 1150 nm, the first wave band is 1145 nm to 1155 nm (the center frequency point is 1150 nm, the first wavelength interval is 0 nm, and the wavelength width is 10 nm), 1143 nm to 1153 nm (the center frequency point is 1148 nm, the first wavelength interval is 2 nm, and the wavelength width is 10 nm), or 1140 nm to 1160 nm (the center frequency point is 1150 nm, the first wavelength interval is 0 nm, and the wavelength width is 20 nm), etc.

[0165] In this way, on the one hand, by limiting the first wavelength interval, the center frequency point of the first waveband can be made to be close to or even coincide with the photoluminescence peak. In this case, the first image data contains most of the photoluminescence signal. On the other hand, by limiting the wavelength width of the first waveband, the problem of too wide first waveband introducing more environmental signals and causing the photoluminescence signal to account for a small proportion of the total signal can be avoided. As can be seen, by using the above-mentioned design of the first waveband, the first image data can have more photoluminescence signals and the proportion of photoluminescence signals is high; thereby facilitating the improvement of the efficiency and accuracy of detection.

[0166] In some embodiments, the second wavelength interval is greater than or equal to 5 nm. For example, the second wavelength interval can be 5 nm to 10 nm, 10 nm to 20 nm, 20 nm to 40 nm, 40 nm to 60 nm, or 60 nm to 80 nm, etc.; and in another example, the second wavelength interval can be 5 nm, 10 nm, 15 nm, 20 nm, 30 nm, 40 nm, 50 nm, 60 nm, 70 nm, or 80 nm, etc. In this way, the second waveband can be far away from the photoluminescence peak. In this case, the second image data contains less photoluminescence signal. Thus, when detecting the photovoltaic panel by the first image data and the second image data, more and cleaner photoluminescence signals can be obtained; thereby facilitating the improvement of the efficiency and accuracy of detection.

[0167] In the above scheme, although the environmental signal in the first waveband and the second waveband changes little, there is still some difference. Therefore, in some embodiments, the second wavelength interval is limited to not more than 80 nm. For example, the second wavelength interval can be 5 nm, 10 nm, 15 nm, 20 nm, 30 nm, 40 nm, 50 nm, 60 nm, 70 nm, or 80 nm, etc. In this way, the difference between the environmental signals in the first image data and the second image data can be minimized, thereby more facilitating the improvement of the accuracy of the obtained photoluminescence detection image, and further improving the accuracy of fault detection by the photoluminescence detection image.

[0168] In some embodiments, the wavelength width of the second waveband is equal to the wavelength width of the first waveband, for example, both are 10 nm or 20 nm. In this way, on the one hand, the first image data obtained by the first waveband can contain the main photoluminescence signal, and on the other hand, the similarity of the environmental signals in the first image data and the second image data can be higher, thereby making the subtraction of the environmental signals simpler and more accurate.

[0169] For example, the photoluminescence peak is 1150 nm, the second wavelength band is 1135 nm to 1145 nm (the center frequency point is 1140 nm, the second wavelength interval is 10 nm, and the wavelength width is 10 nm), 1155 nm to 1165 nm (the center frequency point is 1160 nm, the second wavelength interval is 10 nm, and the wavelength width is 10 nm), 1125 nm to 1135 nm (the center frequency point is 1130 nm, the second wavelength interval is 20 nm, and the wavelength width is 10 nm), or 1120 nm to 1140 nm (the center frequency point is 1130 nm, the second wavelength interval is 20 nm, and the wavelength width is 20 nm), and the like.

[0170] In step S10, the first image data and the second image data can be obtained by the detection device 1 provided in the above embodiments. In this case, the first wavelength band is the filtering wavelength band when the adjustable filtering device 4 in the detection device 1 is in the first state, and the second wavelength band is the filtering wavelength band when the adjustable filtering device 4 in the detection device 1 is in the second state.

[0171] Step S20: subtracting the first image data and the second image data to obtain a photoluminescence detection image.

[0172] Based on the relationship between the first image data and the second image data, after obtaining the first image data and the second image data, the image data containing only the photoluminescence signal can be obtained by subtracting the first image data and the second image data, so as to realize the purpose of imaging only the photoluminescence signal and form the photoluminescence detection image corresponding to the photoluminescence signal.

[0173] The image processing method in step S20 can be executed by the processor 2 of the detection device 1 in the above embodiments, or can be executed by a processing device outside the detection device 1; the processing device can be a processing module specially used for image processing, or can be a computer in the photovoltaic management system 130 (for reference Figure 1 ).

[0174] In some embodiments, before the first image data and the second image data are processed to obtain the photoluminescence detection image, the first image data and the second image data can be subjected to intensity compensation; here, the intensity compensation is used to compensate for the difference in the ambient signal in the first image data and the second image data, so as to reduce or even eliminate the difference in the ambient signal in the two, thereby more favorably improving the accuracy of photoluminescence signal detection and improving the accuracy of fault detection through the photoluminescence signal.

[0175] In some embodiments, for the formed photoluminescence detection image, the gray threshold of the photoluminescence detection image can be adjusted according to the irradiance value, so as to improve the problem that the detection result is affected by different irradiance due to factors such as weather, time and location.

[0176] In some embodiments, when the irradiance is lower than a set value, the light supplement lamp is controlled to supplement light to the target detection area, so as to improve the problem that the detection result is affected by different irradiance due to factors such as weather, time and location.

[0177] Please continue to refer to Figure 1 , as described above, the photovoltaic power generation system 100 provided in the related art includes a photovoltaic management system 130, an inverter 120 and a plurality of photovoltaic strings 110. Each photovoltaic string 110 includes a plurality of photovoltaic panels 101, and each photovoltaic panel 101 includes a plurality of cell units. The plurality of photovoltaic strings 110 are connected to the inverter 120, and the inverter 120 is connected to the photovoltaic management system 130. The photovoltaic management system 130 is used for managing and monitoring the photovoltaic power generation system 100.

[0178] The current-voltage monitoring system (IV system) is usually provided in the photovoltaic management system 130. By scanning the current-voltage (IV) curve of the photovoltaic string 110, the working condition of the photovoltaic string 110 can be monitored, so that the abnormal photovoltaic string 110 can be found. However, this method can only locate the abnormality to a certain photovoltaic string 110, and the application scenario is relatively effective.

[0179] Based on this, the embodiment of the present application further provides a detection method of a photovoltaic power generation system 100. The detection method cooperates with the current-voltage monitoring system (IV system) in the detection device 1 in the above embodiment to realize more accurate positioning, more accurate and comprehensive fault identification.

[0180] Specifically, as shown in Figure 16 , the detection method includes:

[0181] Step S100: controlling the inverter to reduce the current of the photovoltaic string to be detected.

[0182] In step S100, the photovoltaic string to be detected can be the photovoltaic string 110 to be detected according to the detection task, or the abnormal photovoltaic string 110 found by the current-voltage monitoring system by scanning the current-voltage (IV) curve of the photovoltaic string 110. After the current-voltage monitoring system finds the abnormal photovoltaic string 110, the staff can be notified to conduct on-site detection, or the patrol unmanned aerial vehicle can be controlled to conduct on-site detection. During the on-site detection,

[0183] By reducing the current of the photovoltaic string 110 to be detected, the carrier ratio for power generation of the photovoltaic panel 101 can be reduced, and the carrier ratio for photoluminescence can be increased, so as to increase the intensity of the photoluminescence signal; and then the difficulty of obtaining the photoluminescence signal is reduced, and the accuracy of the fault identification in the later stage is improved.

[0184] Step S200: detecting the photovoltaic string to be detected by using the detection device to form a photoluminescence detection image.

[0185] The detection device 1 provided in the embodiments of the present application is used to detect the abnormal photovoltaic string 110. The detection device 1 and the detection method can refer to the above embodiments, and will not be described here. The photoluminescence detection image formed by detecting the photovoltaic string 110 to be detected can be obtained through step S200.

[0186] Step S300: positioning the fault position based on the photoluminescence detection image.

[0187] After obtaining the photoluminescence detection image, the photovoltaic panel 101 with fault can be positioned through image analysis.

[0188] In some embodiments, through the analysis of the photoluminescence detection image, the type of fault can also be identified, and the fault position can be positioned to the specific panel unit of the photovoltaic panel.

[0189] In the detection method of the photovoltaic power generation system 100 provided in the embodiments of the present application, by using the cooperation of the current-voltage monitoring system and the detection device 1 provided in the embodiments of the present application, the rapid and accurate fault identification can be realized, and the inspection efficiency and accuracy can be improved.

[0190] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited to this. Any person skilled in the art can easily think of changes or replacements within the technical range disclosed in the present application, which should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. An inspection apparatus of a photovoltaic panel, characterized by, The detection device comprises a lens, an adjustable light filtering device, an image sensor and a processor; wherein the lens and the adjustable light filtering device are both arranged on the light inlet side of the image sensor, the lens is used for converging light in a target detection area onto the image sensor, and the adjustable light filtering device is used for filtering light converging onto the image sensor through the lens; The adjustable light filtering device has switchable first and second light filtering wave bands; the first light filtering wave band contains a photoluminescence peak of a photovoltaic cell panel, the center frequency point of the first light filtering wave band and the wavelength interval of the photoluminescence peak are a first wavelength interval; the center frequency point of the second light filtering wave band and the wavelength interval of the photoluminescence peak are a second wavelength interval; the first wavelength interval is smaller than the second wavelength interval; The image sensor is used for converting incident light of the first light filtering wave band into first image data and converting incident light of the second light filtering wave band into second image data; The processor is electrically connected with the image sensor and is configured to form a photoluminescence detection image according to the first image data and the second image data, or is configured to send the first image data and the second image data to a target device.

2. The detection device of claim 1, wherein, The adjustable light filtering device comprises an electrochromic filter and a control power supply, the electrochromic filter comprises a first transparent substrate, a first transparent electrode, an electrochromic filter layer, an electrolyte layer, an ion storage layer, a second transparent electrode and a second transparent substrate which are arranged in layers; The control power supply is electrically connected with the first transparent electrode and the second transparent electrode respectively and is configured to output a first voltage signal and a second voltage signal to the electrochromic filter; Under the action of the first voltage signal, the light filtering wave band of the electrochromic filter is the first light filtering wave band; Under the action of the second voltage signal, the light filtering wave band of the electrochromic filter is the second light filtering wave band.

3. The detection device of claim 2, wherein, The control power supply comprises a power supply, a storage capacitor, a first control switch and a second control switch; the two ends of the storage capacitor are electrically connected with the two ends of the power supply respectively, and the two ends of the storage capacitor are also electrically connected with the first transparent electrode and the second transparent electrode respectively; The first control switch is arranged between the power supply and the storage capacitor and is used for controlling the on-off of the power supply and the storage capacitor; The second control switch is arranged between the storage capacitor and the electrochromic filter and is used for controlling the on-off of the storage capacitor and the electrochromic filter.

4. The detection device according to claim 2 or 3, characterized in that The material of the electrochromic filter layer is tungsten trioxide, and the thickness is 500-600 nm.

5. The detection device according to any one of claims 2 to 4, characterized in that, The lens comprises a lens barrel, the lens barrel has a barrel cavity through along the lens optical axis; the lens further comprises two or more lenses arranged along the lens optical axis in the barrel cavity; The electrochromic filter is arranged in the lens barrel cavity between any adjacent lens or on the side of the lens barrel close to the image sensor or on the side of the lens barrel far from the image sensor.

6. The detection device of claim 1, wherein, The adjustable filter device comprises an interference filter and a driving device for driving the interference filter to rotate around an axis perpendicular to the lens optical axis. The interference filter has a first state and a second state under the driving of the driving device. For incident light propagating along the lens optical axis, the interference filter has a first filter wavelength range in the first state and a second filter wavelength range in the second state.

7. The detection device of claim 6, wherein, The lens comprises a lens barrel having a lens barrel cavity through along the lens optical axis; the lens further comprises two or more lenses arranged along the lens optical axis in the lens barrel cavity. The interference filter is rotatably arranged in the lens barrel cavity around an axis. The interference filter is arranged between any adjacent lens or on the side of the lens barrel close to the image sensor or on the side of the lens barrel far from the image sensor.

8. The detection device of claim 7, wherein, The driving device comprises a first adsorption structure and a second adsorption structure arranged on both sides of the interference filter, and a first electromagnetic device and a second electromagnetic device arranged on the lens barrel. The first electromagnetic device is located outside the first adsorption structure, and the first electromagnetic device generates a magnetic force on the first adsorption structure after being powered on. The second electromagnetic device is located outside the second adsorption structure, and the second electromagnetic device generates a magnetic force on the second adsorption structure after being powered on.

9. The detection device of claim 7, wherein, The driving device comprises a linear slider and a rotating structure, the linear slider is slidably arranged on the lens barrel along the lens optical axis, and has a clamping groove with an opening facing the interference filter; the clamping groove is clamped on the end of the interference filter; The rotating structure is rotatably arranged on the lens barrel around the lens optical axis, and the rotating structure drives the linear slider to move along the lens optical axis during rotation around the lens optical axis.

10. The detection device of claim 1, wherein, The adjustable filter device is a liquid crystal adjustable filter device, an acousto-optic adjustable filter device or a filter wheel.

11. The detection device according to any one of claims 1 to 10, characterized in that, The wavelength width of the first filter wavelength range and the second filter wavelength range is equal.

12. The detection device according to any one of claims 1 to 11, characterized in that, The first wavelength interval is less than 3nm, and the wavelength width of the first filter wavelength range is not more than 20nm.

13. The detection device according to any one of claims 1 to 12, characterized in that, The second wavelength interval is greater than or equal to 5nm and less than or equal to 80nm.

14. The detection device according to any one of claims 1 to 13, characterized in that, The photoluminescence peak is 1150nm, the first filter wavelength range is 1145nm to 1155nm, and the second filter wavelength range is 1135nm to 1145nm.

15. The detection device according to any one of claims 1 to 14, characterized in that, The detection device further comprises an irradiance device for detecting an irradiance value and sending the irradiance value to the processor or the target device.

16. The detection device according to any one of claims 1 to 15, characterized in that, The detection device further comprises a light supplement lamp configured to generate an illumination light beam, wherein the illumination light beam is near-infrared light.

17. A method of detecting a photovoltaic panel, characterized in that, The detection method comprises: converting light in the first wave band and the second wave band in the target detection area into first image data and second image data, respectively; subtracting the first image data from the second image data to obtain a photoluminescence detection image; wherein the first wave band contains a photoluminescence peak of the photovoltaic panel, a center frequency point of the first wave band is separated from a wavelength of the photoluminescence peak by a first wavelength interval, a center frequency point of the second wave band is separated from the wavelength of the photoluminescence peak by a second wavelength interval, and the first wavelength interval is smaller than the second wavelength interval.

18. The detection method of claim 17, wherein, Before the step of subtracting the first image data from the second image data to obtain a photoluminescence detection image, the method further comprises: performing intensity compensation on the first image data and the second image data; wherein the intensity compensation is configured to compensate for differences in ambient signals in the first image data and the second image data.

19. The detection method according to claim 17 or 18, characterized in that, After the step of subtracting the first image data from the second image data to obtain a photoluminescence detection image, the method further comprises: adjusting a grayscale threshold of the photoluminescence detection image according to irradiance.

20. The detection method according to any one of claims 17 to 19, characterized in that, The detection method further comprises: when the irradiance is lower than a set value, controlling the light supplement lamp to supplement light to the target detection area.

21. The detection method according to any one of claims 17 to 20, characterized in that, The wavelength width of the first wave band and the second wave band is equal.

22. The detection method according to any one of claims 17 to 21, characterized in that, The first wavelength interval is less than 3 nm, and the wavelength width of the first wave band is not more than 20 nm.

23. The detection method according to any one of claims 17 to 22, characterized in that, The second wavelength interval is greater than or equal to 5 nm and less than or equal to 70 nm.

24. The detection method according to any one of claims 17 to 23, characterized in that, The photoluminescence peak is 1150 nm, the first wave band is 1145 nm to 1155 nm, and the second wave band is 1135 nm to 1145 nm.

25. A method of detecting a photovoltaic panel system, the method comprising: The photovoltaic panel system comprises a photovoltaic management system, an inverter, and a plurality of photovoltaic strings; each of the photovoltaic strings comprises a plurality of photovoltaic panels, the plurality of photovoltaic strings are connected to the inverter, the inverter is connected to the photovoltaic management system, and the photovoltaic management system comprises a current-voltage monitoring system. The detection method comprises: controlling the inverter to reduce the current of a photovoltaic string to be detected; detecting the photovoltaic string to be detected using the detection device of any one of claims 1 to 16 to form a photoluminescence detection image; and locating a fault position based on the photoluminescence detection image.

26. The detection method of claim 25, wherein, The photovoltaic string to be detected is an abnormal photovoltaic string found by the current-voltage monitoring system.

Images