Photovoltaic cell panel invisible defect detection device based on push-broom imaging

Abstract

The invention discloses a photovoltaic cell panel invisible defect detection device based on push-broom imaging, and relates to the technical field of photovoltaic cell panel application. The device comprises an excitation light source, a light filter, a linear array sensor, a push-broom mechanism and a processing system, the push-broom mechanism and the linear array sensor are both connected with the processing system; the linear array sensor is arranged on the push-broom mechanism; the light filter is arranged at the imaging front end of the linear array sensor; the processing system generates a push-broom control signal to drive the push-broom mechanism to perform push-broom motion; in the push-broom motion process, a light image generated by the photovoltaic cell panel to be detected is projected to the linear array sensor after being filtered by the light filter, and the light image is converted into a one-dimensional push-broom image sequence by the linear array sensor; and the processing system generates a two-dimensional image based on the one-dimensional push-scan image sequence, and obtains an invisible defect detection result of the photovoltaic cell panel to be detected based on the two-dimensional image. According to the invention, large-area imaging of the photovoltaic cell panel is realized, and the accuracy of invisible defect detection is improved.

Description

Technical Field

[0001] The present application relates to the technical field of photovoltaic panel applications, and in particular to a photovoltaic panel invisible defect detection device based on push-scan imaging. Background Art

[0002] Online imaging detection of photovoltaic panels can detect various invisible defects or problems of the panels, including surface contamination, hidden cracks, debris, black spots, broken grids, local heating, etc. The existing online imaging detection technology of photovoltaic panels mainly consists of electroluminescence imaging, photoluminescence imaging, infrared thermal imaging and other technologies. Among them, electroluminescence imaging technology (Electroluminescence imaging) and photoluminescence imaging (Photoluminescence imaging) technology have the characteristics of many types of defects to be detected, high image clarity, and high detection efficiency, and are currently the key technologies to be developed. Among them, electroluminescence is to apply a certain reverse voltage to the PN junction of the photovoltaic panel, thereby inducing it to emit light of a certain wavelength; photoluminescence is to irradiate the semiconductor material of the photovoltaic panel with light of a certain wavelength, thereby stimulating it to emit fluorescence of a certain wavelength. The spectral energy of electroluminescence or photoluminescence of silicon crystal materials is mainly distributed in the short-wave infrared range of 1050nm to 1250nm; against the background of these electroluminescence or photoluminescence backgrounds, various invisible defects of photovoltaic panels can be revealed, thus creating conditions for imaging technology.

[0003] At present, although online imaging detection technologies for photovoltaic panels such as electroluminescent imaging, photoluminescent imaging, and infrared thermal imaging can realize scanning imaging of photovoltaic panels, photovoltaic panels, as key equipment for solar power generation facilities, usually have a large area. Due to the interference of sunlight irradiance, existing electroluminescent imaging or photoluminescent imaging technologies mainly use area array short-wave infrared cameras such as area array InGaAs for shooting. Therefore, the target area of ​​each shooting is limited by the field of view of the camera, which is difficult to adapt to the shooting requirements of large areas. For example, the Chinese invention patent application CN118199517A known to the inventor mainly uses the movement of photovoltaic panels to achieve scanning, and is not suitable for continuous large-area imaging. The inventor's known world invention patent applications WO2011152445A1 and WO2017172611A1, Chinese invention patent applications CN201340393Y, CN118443779A and CN115861223A, and the documents "Research on photovoltaic panel defect detection technology based on high frame rate InGaAs camera. Wu Sheng. Nanjing University of Science and Technology. 2021-12-01", "Research on solar panel defect detection technology under high illumination based on InGaAs camera. Chi Linhui. Nanjing University of Science and Technology. 2020-12-01" do not involve the problem of large-area push-scan imaging. Summary of the invention

[0004] The purpose of this application is to provide a photovoltaic panel invisible defect detection device based on push-scan imaging, which can achieve large-area imaging of photovoltaic panels and improve the accuracy of invisible defect detection.

[0005] To achieve the above objectives, this application provides the following solutions:

[0006] In a first aspect, the present application provides a photovoltaic panel invisible defect detection device based on push-scanning imaging, comprising: an excitation light source, an optical filter, a linear array sensor, a push-scanning mechanism, and a processing system;

[0007] The excitation light source is used to output excitation light so as to make the photovoltaic panel to be inspected generate a light image;

[0008] The push-sweep mechanism and the linear array sensor are both connected to the processing system; the linear array sensor is arranged on the push-sweep mechanism; the optical filter is arranged at the imaging front end of the linear array sensor;

[0009] The processing system generates a push-sweep control signal to drive the push-sweep mechanism to perform a push-sweep motion; during the push-sweep motion, the light image generated by the photovoltaic panel to be inspected is filtered by the filter and then projected onto the linear array sensor, and is converted into a one-dimensional push-sweep image sequence by the linear array sensor; the processing system generates a two-dimensional image based on the one-dimensional push-sweep image sequence, and obtains the invisible defect detection result of the photovoltaic panel to be inspected based on the two-dimensional image.

[0010] Optionally, the optical filter is a near-infrared narrow-band filter; the spectral transmittance of the near-infrared narrow-band filter matches the spectral sensitivity of the linear array sensor.

[0011] Optionally, the linear array sensor is a near infrared sensor or a short wave infrared sensor.

[0012] Optionally, the push-sweeping mechanism is an electrically controlled turntable or an electrically controlled translation table.

[0013] Optionally, the electrically-controlled turntable or the electrically-controlled translation stage is connected to the processing system via a USB.

[0014] Optionally, the push-broom mechanism is a drone; the drone and the linear array sensor are both wirelessly connected to the processing system.

[0015] Optionally, the processing system is one or more of a microcomputer, a laptop computer, a smart phone, a tablet computer, an Internet of Things device, and a portable wearable device.

[0016] Optionally, the excitation light source is a photoexcitation light source or an electroluminescent driving power source.

[0017] Optionally, the photoexcitation light source is a sunlight light source.

[0018] Optionally, the voltage of the electroluminescent driving power supply is determined based on the series resistance of components in the photovoltaic panel to be detected.

[0019] According to the specific embodiments provided in this application, this application has the following technical effects:

[0020] The present application provides a photovoltaic panel invisible defect detection device based on push-scanning imaging, which can realize large-area imaging of photovoltaic panels by setting a push-scanning mechanism to drive a linear array sensor to perform imaging scanning motion. In addition, by setting a filter, it is possible to filter out unnecessary spectral energy in ambient light and eliminate the interference of outdoor high irradiance environment on imaging, thereby improving the accuracy of invisible defect detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 A schematic diagram of the structure of a photovoltaic panel invisible defect detection device based on push-scan imaging provided in one embodiment of the present application;

[0023] Figure 2 A schematic diagram of the principle of a photovoltaic panel defect detection device using an electrically controlled turntable and electroluminescent imaging provided in one embodiment of the present application;

[0024] Figure 3 A schematic diagram of the principle of a photovoltaic panel defect detection device using a drone and photoluminescence imaging provided in one embodiment of the present application;

[0025] Figure 4 A schematic diagram of the narrowband filter transmittance, InGaAs camera spectral sensitivity, and photovoltaic panel photoluminescence or electroluminescence spectrum curve provided in one embodiment of the present application.

[0026] Marking Description:

[0027] 1-photovoltaic cell panel to be detected, 2-photoexcitation light source, 3-electroluminescent driving power supply, 4-linear array sensor, 5-push-sweep mechanism, 51-electrically controlled turntable, 52-UAV, 6-processing system, 7-filter. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0029] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0030] In an exemplary embodiment, the present application provides a photovoltaic panel invisible defect detection device based on push-scan imaging, such as Figure 1 As shown, the device includes: an excitation light source, an optical filter 7, a linear array sensor 4, a push-scan mechanism 5 and a processing system 6.

[0031] The excitation light source is used to output excitation light to make the photovoltaic cell panel 1 to be inspected generate a light image. The photovoltaic cell panel 1 to be inspected can be a single crystal silicon or polycrystalline silicon photovoltaic cell panel.

[0032] The push-sweep mechanism 5 and the linear array sensor 4 are both connected to the processing system 6. The linear array sensor 4 is arranged on the push-sweep mechanism 5. The optical filter 7 is arranged at the imaging front end of the linear array sensor 4.

[0033] The processing system 6 generates a push-sweep control signal to drive the push-sweep mechanism 5 to perform a push-sweep motion. During the push-sweep motion, the light image generated by the photovoltaic panel 1 to be inspected is filtered by the filter 7 and then projected to the line array sensor 4, which is converted into a one-dimensional push-sweep image sequence by the line array sensor 4. The processing system 6 generates a two-dimensional image based on the one-dimensional push-sweep image sequence, and obtains the invisible defect detection result of the photovoltaic panel 1 to be inspected based on the two-dimensional image.

[0034] In another exemplary embodiment of the present application, in order to further filter out most of the spectral energy of the ambient light, thereby suppressing or eliminating the adverse effects of high irradiance ambient light on photoluminescence imaging or electroluminescence imaging, the filter 7 used in the present application may be a near-infrared narrow-band filter. The spectral transmittance of this near-infrared narrow-band filter matches the spectral sensitivity of the linear array sensor 4.

[0035] In another exemplary embodiment of the present application, in order to further improve the imaging accuracy, the linear array sensor 4 used in the present application may be a near infrared sensor or a short wave infrared sensor, such as an InGaAs camera and other types of linear array sensors 4, which have high sensitivity in the wavelength range of 1050nm to 1250nm.

[0036] In another exemplary embodiment of the present application, in order to improve the convenience of detection, the push-scan mechanism 5 provided in the present application can be an electrically controlled turntable or an electrically controlled translation table, wherein the electrically controlled turntable or the electrically controlled translation table can be connected to the processing system 6 via a USB.

[0037] In another exemplary embodiment of the present application, in order to detect defects in photovoltaic panels that have been installed by the user, a drone equipped with a linear array sensor can be used as a push-sweep mechanism. At this time, the drone and the linear array sensor 4 are both wirelessly connected to the processing system 6, so that the user can perform push-sweep control and one-dimensional imaging scanning of the drone.

[0038] In another exemplary embodiment of the present application, the processing system can be one or more of a microcomputer, a laptop computer, a smart phone, a tablet computer, an Internet of Things device, and a portable wearable device, for controlling the movement or rotation of the push-scan mechanism 5, the shooting of the linear array camera, and merging a one-dimensional push-scan image sequence into a two-dimensional image.

[0039] For example, when a smartphone is used as a processing system, functional software for detecting invisible defects of photovoltaic panels can be implanted in the smartphone so as to view two-dimensional images or obtain invisible defect detection results of the photovoltaic panels to be inspected based on the received two-dimensional images.

[0040] In another exemplary embodiment of the present application, Figure 1 As shown, the excitation light source is a photoexcitation light source 2 or an electroluminescent driving power supply 3. Among them, the photoexcitation light source 2 can be a narrow-band light source or a daylight light source in the near-infrared band. This narrow-band light source in the near-infrared band can be a laser light source or an LED light source. The electroluminescent driving power supply 3 is a set of reverse DC voltages applied to the PN junction of the photovoltaic panel, and the magnitude of the reverse DC voltage is related to the series resistance of the photovoltaic panel assembly. The photovoltaic panel generates photoluminescence under the irradiation of the near-infrared excitation light source, or generates electroluminescence under the action of the electroluminescent driving voltage. The spectral energy of the photoluminescence or electroluminescence is mainly distributed in the short-wave infrared range of 1050nm to 1250nm.

[0041] In another exemplary embodiment of the present application, Figure 2 As shown, the photovoltaic panel defect detection device provided by the present application is described by taking the use of an electrically controlled turntable 51 as the push-sweep mechanism 5 and the use of an electroluminescent driving power supply 3 as the excitation light source as an example. Figure 4As shown, in this embodiment, the central wavelength of the near-infrared narrow-band filter used is 1150nm. A linear array InGaAs camera is used as the linear array sensor 4. A microcomputer is used as the processing system 6. The microcomputer and its peripheral interface USB are used for turntable control, linear array InGaAs camera control, image processing, etc. The photovoltaic panel 1 to be detected generates electroluminescence and forms a defect image under the action of the electroluminescent driving power supply 3. After one line of the electroluminescent image of the photovoltaic panel passes through the near-infrared narrow-band filter, it is converted into a one-dimensional electrical signal image by the linear array InGaAs camera, and so on, a one-dimensional push-scan image sequence is obtained. The electric-controlled turntable 51 drives the linear array InGaAs camera to complete the push-scan imaging process under the control of the microcomputer. The microcomputer merges the continuously captured one-dimensional push-scan image sequence into a complete two-dimensional image. During the entire shooting process, the infrared narrow-band filter filters out most of the spectral energy reflected by the ambient light from the photovoltaic panel 1 to be detected.

[0042] Further, if Figure 4 As shown in the figure, the linear array InGaAs camera can fully adapt to photo / electroluminescence and has better imaging effect than silicon CCD / CMOS camera.

[0043] In another exemplary embodiment of the present application, Figure 3 As shown, the photovoltaic panel defect detection device provided by the present application is described by using a drone 52 as a push-sweep mechanism 5 and a photoexcitation light source 2 as an excitation light source. In this embodiment, a linear array InGaAs camera is still used as a linear array sensor 4, and a microcomputer is used as a processing system 6. The microcomputer and its peripheral interface USB implement drone 52 control, camera control, image processing, etc. The photovoltaic panel 1 to be detected generates a photoluminescent defect image under the irradiation of high-irradiance sunlight. After one line of the photoluminescent image passes through a near-infrared narrow-band filter, it is converted into a 1-dimensional electrical signal image by the linear array InGaAs camera, and so on, a one-dimensional push-sweep image sequence is obtained. The drone 52 is equipped with a linear array InGaAs camera and is connected to the microcomputer via a wireless digital transmission signal. Under the control of the microcomputer, the drone 52 drives the linear array InGaAs camera to complete the 1-dimensional push-sweep imaging process. The microcomputer merges the continuously captured one-dimensional push-sweep image sequence into a complete two-dimensional image. During the shooting process of this embodiment, the near-infrared narrow-band filter also filters out most of the spectral energy reflected by the photovoltaic panel from the ambient sunlight.

[0044] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0045] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. At the same time, for those skilled in the art, according to the ideas of this application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting this application.

Claims

1. A photovoltaic panel invisible defect detection device based on push-scan imaging, characterized in that: The photovoltaic panel invisible defect detection device based on push-scanning imaging comprises: an excitation light source, a filter, a linear array sensor, a push-scanning mechanism and a processing system; The excitation light source is used to output excitation light so as to make the photovoltaic panel to be inspected generate a light image; The push-sweep mechanism and the linear array sensor are both connected to the processing system; the linear array sensor is arranged on the push-sweep mechanism; the optical filter is arranged at the imaging front end of the linear array sensor; The processing system generates a push-sweep control signal to drive the push-sweep mechanism to perform a push-sweep motion; during the push-sweep motion, the light image generated by the photovoltaic panel to be inspected is filtered by the filter and then projected onto the linear array sensor, and is converted into a one-dimensional push-sweep image sequence by the linear array sensor; the processing system generates a two-dimensional image based on the one-dimensional push-sweep image sequence, and obtains the invisible defect detection result of the photovoltaic panel to be inspected based on the two-dimensional image.

2. The photovoltaic panel invisible defect detection device based on push-scanning imaging according to claim 1 is characterized in that: The optical filter is a near-infrared narrow-band filter; the spectral transmittance of the near-infrared narrow-band filter matches the spectral sensitivity of the linear array sensor.

3. The photovoltaic panel invisible defect detection device based on push-scanning imaging according to claim 1 is characterized in that: The linear array sensor is a near infrared sensor or a short wave infrared sensor.

4. The photovoltaic panel invisible defect detection device based on push-scan imaging according to claim 1, characterized in that: The push-sweeping mechanism is an electrically controlled rotating table or an electrically controlled translation table.

5. The photovoltaic panel invisible defect detection device based on push-scan imaging according to claim 4 is characterized in that: The electrically controlled turntable or the electrically controlled translation stage is connected to the processing system via a USB.

6. The photovoltaic panel invisible defect detection device based on push-scanning imaging according to claim 1, characterized in that: The push-broom mechanism is a drone; the drone and the linear array sensor are both wirelessly connected to the processing system.

7. The photovoltaic panel invisible defect detection device based on push-scanning imaging according to claim 1, characterized in that: The processing system is one or more of a microcomputer, a laptop computer, a smart phone, a tablet computer, an Internet of Things device, and a portable wearable device.

8. The photovoltaic panel invisible defect detection device based on push-scan imaging according to claim 1, characterized in that: The excitation light source is a photoexcitation light source or an electroluminescent driving power source.

9. The photovoltaic panel invisible defect detection device based on push-scanning imaging according to claim 8, characterized in that: The photoexcitation light source is a sunlight light source.

10. The photovoltaic panel invisible defect detection device based on push-scan imaging according to claim 8, characterized in that: The voltage of the electroluminescent driving power supply is determined based on the series resistance of the components in the photovoltaic panel to be detected.

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