Photovoltaic module subfissure detection and repair device

Abstract

The invention relates to the technical field of photovoltaic subfissure repair, and discloses a photovoltaic module subfissure detection and repair device which comprises a step-down transformer, a step-up transformer, a fault point positioning film and a fault point repair film. The fault point repairing film comprises a repairing flexible base material and a related coating, the fault point repairing film is attached to the light receiving surface of the photovoltaic panel, and the fault point positioning film comprises a positioning flexible base material and a plurality of coating layers and is also attached to the light receiving surface. The step-down transformer and the step-up transformer are connected according to a specific mode, the step-down transformer inputs current which does not exceed a threshold value to the positive and negative electrodes of the photovoltaic panel, the step-up transformer inputs high-voltage pulses after the positioning film presents hot spots, and the fault point positioning film shows subfissure through conversion of fluorescent paint and then is replaced with a repairing film. And the hot melting layer is melted through high-voltage discharge to fill the subfissure area.

Description

Technical Field

[0001] This application relates to the technical field of photovoltaic hidden crack repair, and particularly to a device for detecting and repairing hidden cracks in photovoltaic modules. Background Art

[0002] During the use of photovoltaic modules, hidden cracks often occur, which may be caused by factors such as defects in the manufacturing process, collisions during transportation, stress during installation, and long-term environmental impacts. Hidden cracks will affect the photoelectric conversion efficiency of photovoltaic modules. In severe cases, it will trigger the hot spot effect, resulting in local overheating, further damaging the photovoltaic modules, and reducing their service life and power generation performance. However, traditional detection and repair methods may have certain limitations. For example, they cannot accurately locate the position of hidden cracks, it is difficult to comprehensively detect various types and degrees of hidden cracks, or they cannot effectively repair the detected hidden cracks after detection, and cannot fundamentally solve the damage problem of hidden cracks to photovoltaic modules. Summary of the Invention

[0003] In order to provide a more perfect and efficient hidden crack detection and repair solution, improve the reliability and power generation performance of photovoltaic modules, and extend their service life.

[0004] This application provides a device for detecting and repairing hidden cracks in photovoltaic modules.

[0005] This application provides a device for detecting and repairing hidden cracks in photovoltaic modules, adopting the following technical solutions: A device for detecting and repairing hidden cracks in photovoltaic modules includes a step-down transformer, a step-up transformer, a fault point positioning film, and a fault point repair film; The fault point repair film includes a repair flexible substrate. One side of the repair flexible substrate is provided with a heat preservation layer, and the other side of the repair flexible substrate has a hot melt layer. A repair conductive coating is provided on the side of the hot melt layer away from the repair flexible substrate; the side of the fault point repair film with the repair conductive coating is used for evenly attaching to the light-receiving surface of the photovoltaic panel to be tested; The fault point positioning film includes a positioning flexible substrate. One side of the positioning flexible substrate is sprayed with a thermochromic coating layer, and the other side of the positioning flexible substrate is sprayed with a mixed fluorescent coating layer containing at least two different wavelength fluorescent powders. A positioning conductive coating is also sprayed on the side of the mixed fluorescent coating layer away from the positioning flexible substrate; the side of the fault point positioning film with the positioning conductive coating is used for evenly attaching to the light-receiving surface of the photovoltaic panel to be tested; After the two AC power input terminals of the step-down transformer and the step-up transformer are connected in parallel, the two AC power input terminals are connected to an AC power supply; the two power output terminals of the step-down transformer are connected to the positive and negative output terminals of the photovoltaic panel to be tested; one signal output terminal of the step-up transformer is connected to the repair conductive coating of the fault point repair film and the ground terminal, and the other signal output terminal is connected to one of the power output terminals of the step-down transformer. The repair conductive coating of the fault point repair film is connected to the outer frame of the photovoltaic panel to be tested and the ground terminal; When the fault point location film is evenly attached to the light-receiving surface of the photovoltaic panel to be tested, the two power output terminals of the step-down transformer input a current not greater than a set threshold to the positive and negative poles of the photovoltaic panel to be tested; after the hot spot damage area on the fault point location film appears, the step-up transformer inputs a high-voltage pulse signal to the positive or negative pole of the photovoltaic panel to be tested, and high-voltage discharge occurs at the insulation weak point of the photovoltaic module with hidden cracks; the infrared signal generated by the discharge is changed into a kind of visible light through the fluorescent coating of the first wavelength, and the ultraviolet ray generated by the discharge is changed into another kind of visible light through the fluorescent coating of the second wavelength, forming a luminous hidden crack display on the fault point location film; When a luminous hidden crack display is formed on the fault point location film, the fault point location film is replaced with the fault point repair film; the step-up transformer inputs a high-voltage pulse signal to the positive or negative pole of the photovoltaic panel to be tested, and high-voltage discharge occurs at the insulation weak point of the photovoltaic module with hidden cracks. The hot melt layer melts under the heating of the high-voltage arc and then fills the hidden crack area.

[0006] By adopting the above technical solution, by using the thermochromic coating layer on the fault location film, the area where problems may exist can be preliminarily located according to the situation presented by the hot spot damage area on the photovoltaic module. At the same time, by inputting a high-voltage pulse signal through the step-up transformer, high-voltage discharge occurs at the weak insulation part of the hidden crack. The infrared and ultraviolet signals generated by the discharge can be converted into different visible lights by different wavelength phosphors in the hybrid fluorescent coating layer, forming a luminous hidden crack display on the location film, realizing the precise visualization of the hidden crack position, overcoming the problem that it is difficult to accurately locate the hidden crack by traditional detection methods, and providing accurate position information for the subsequent repair work. When the hidden crack location is completed, the fault location film is replaced with a fault repair film, and a high-voltage pulse signal is continuously input through the step-up transformer. The hot-melt layer melts under the heating of the high-voltage arc to fill the hidden crack area, realizing the effective repair of the hidden crack, avoiding the long-term negative impact of the hidden crack on the performance of the photovoltaic module, and helping to maintain and restore the photoelectric conversion efficiency of the photovoltaic module. The multi-layer structure design of the fault repair film and the fault location film, including their respective flexible substrates, corresponding coating layers and conductive coating layers, ensures good adhesion to the light-receiving surface of the photovoltaic panel and the realization of functions. The connection method and operation process of the step-down transformer and the step-up transformer ensure the effective transmission of current and pulse signals during the detection and repair process. Each component works together to realize the coherent operation from detection to repair, improving the convenience of operation and the reliability of the equipment. This application can timely detect and repair hidden cracks, avoid problems such as hot spots and local overheating caused by hidden cracks, can significantly extend the service life of photovoltaic modules, improve the power generation performance and economic benefits of the entire photovoltaic power station, and reduce the risk of power generation efficiency decline and premature component failure caused by hidden cracks.

[0007] Optionally, transparent silica gel particles are sprayed on the side of the repair flexible substrate away from the heat insulation layer to form the hot-melt layer.

[0008] By adopting the above technical solutions, the transparent silica gel particles can rapidly melt under arc heating. They have good fluidity and can fully fill the crack areas of the photovoltaic module, effectively bridging the cracks, preventing the further expansion of the hidden cracks, ensuring the integrity of the module structure, and thus maintaining the normal power generation function of the photovoltaic module. Compared with other hot-melt materials, the transparent silica gel particles have a suitable melting point and good adhesiveness. After melting, they can closely adhere to the surface of the hidden crack part, forming a stable filling structure, improving the strength and stability of the repaired module. The transparent silica gel particles have a high light transmittance in the unmelted state and will not significantly affect the light absorption and conversion efficiency of the light-receiving surface of the photovoltaic module. This is crucial for the performance of the photovoltaic module because even during the repair process, the interference with the normal power generation function of the module should be minimized. During long-term use, the transparent silica gel can maintain good optical stability and will not undergo obvious optical property deterioration due to factors such as light irradiation and temperature changes, ensuring the continuous stability of the power generation performance of the photovoltaic module. The transparent silica gel has good compatibility with the flexible substrate and can firmly adhere to the flexible substrate without easy detachment or delamination. Under different environmental conditions, such as high temperature, high humidity, and ultraviolet irradiation, the combined structure of the transparent silica gel and the flexible substrate can remain stable without chemical reactions or physical deformations, thus ensuring the reliability and durability of the fault point repair film, reducing the frequency of re-repair due to the failure of the repair material, and lowering the maintenance cost.

[0009] Optionally, a metal powder is uniformly vapor-deposited on one side of the repair flexible substrate to form the repair conductive coating, wherein the metal powder particles of the metal powder layer are no larger than 1000 mesh.

[0010] By adopting the above technical solutions, the metal powder has excellent electrical conductivity, and the metal powder layer formed by vapor deposition can efficiently conduct high-voltage pulse signals. When the step-up transformer outputs high-voltage pulses, the conductive repair coating can ensure the stable transmission of signals to the cracked part of the photovoltaic module, ensuring a reliable high-voltage discharge phenomenon at the insulation-weak position of the crack, thereby accurately locating the cracked part and providing accurate position information for subsequent repair work. Compared with other conductive materials or coating methods, the coating formed by vapor-depositing metal powder is more excellent in electrical conductivity and signal transmission stability, can effectively avoid signal attenuation or interference, and improve the detection accuracy of the repair device. The vapor deposition process can evenly attach the metal powder to the repair flexible substrate to form a conductive coating with uniform thickness and dense texture. This uniformity ensures that the high-voltage pulse signals can be evenly distributed across the contact surface between the fault-point repair film and the photovoltaic module, avoiding local signal over-strength or over-weakness, so that the discharge phenomenon at the crack is more consistent and obvious, which is conducive to improving the accuracy and reliability of detection. At the same time, the closely adhering metal powder layer can better adapt to the deformation of the flexible substrate and is not easily detached or damaged during installation and use, ensuring the long-term stability and durability of the repair device. Selecting metal powder particles with a mesh size not greater than 1000 can meet the requirements of the fine vapor deposition process. While ensuring good electrical conductivity, a relatively thin conductive coating can be formed, which helps to realize the miniaturization and lightweight design of the fault-point repair film. This is very beneficial for installation and operation on the surface of the photovoltaic module, and will not have additional negative impacts on the performance of the photovoltaic module due to the excessive volume and weight of the repair device itself, such as blocking light, increasing wind load, etc. At the same time, it is also convenient to carry and use in practical applications, improving the convenience and flexibility of the repair work.

[0011] Optionally, a porous thermal insulation particle is evenly sprayed on one side of the repair flexible substrate to form the thermal insulation layer.

[0012] By adopting the above technical solution, the thermal insulation layer formed by the porous thermal insulation particles can play a good role in heat insulation during the repair process. When the hot melt layer melts and fills the crack area, certain heat will be generated. If the heat dissipates too quickly, it may cause the hot melt layer to not fully melt and fill, affecting the repair effect. The thermal insulation layer can slow down the transfer of heat to the surrounding environment, concentrate the heat at the crack and its nearby areas, ensure that the hot melt layer maintains good fluidity at an appropriate temperature, so as to achieve more sufficient and effective filling, improve the repair quality, and reduce the risk of repair failure caused by insufficient temperature. A suitable temperature environment is also crucial for each component of the repair device. The thermal insulation layer helps to maintain a relatively stable temperature field, reduce the thermal stress impact of temperature fluctuations on the flexible substrate, conductive coating and other related components, and prevent problems such as component deformation, cracking or connection loosening caused by frequent thermal expansion and contraction, thereby extending the service life of the repair device, improving its stability and reliability, reducing the need for frequent replacement or maintenance due to device failures, reducing the maintenance cost, and ensuring the continuous and effective development of the photovoltaic module crack repair work. By reducing heat dissipation, the thermal insulation layer enables the energy required during the repair process to act more concentratedly on the crack repair link, improving the energy utilization efficiency. This means that under the same energy input, a better repair effect can be obtained, or when the same repair effect is achieved, the power requirement for energy supply equipment such as step-up transformers can be reduced, reducing energy consumption, conforming to the concept of energy conservation and environmental protection, and having important economic and environmental significance for the maintenance of large-scale photovoltaic power stations.

[0013] Optionally, it further includes a camera device for taking a positioning image of the fault point positioning film; the controller identifies the luminous crack display from the positioning image; The fault point positioning film is divided into multiple positioning areas, and according to the distribution of the luminous crack display in the multiple positioning areas, the number of the positioning areas involved in the luminous crack display is calculated as the number of crack areas; The voltage of the high-voltage pulse signal is adjusted positively correlated with the number of crack areas; the larger the number of crack areas, the higher the voltage of the high-voltage pulse signal; the smaller the number of crack areas, the lower the voltage of the high-voltage pulse signal.

[0014] By adopting the above technical solutions, first, the positioning image of the fault point positioning film can be accurately captured by the imaging device, providing intuitive and accurate data for crack detection. The controller identifies the luminous crack display from the image, divides the positioning film into regions, calculates the number of crack regions, realizes the quantitative evaluation of the crack situation, and improves the accuracy and objectivity of crack positioning. Secondly, adjusting the voltage of the high-voltage pulse signal in positive correlation with the number of crack regions can achieve the adaptive adjustment of the voltage. When there are more crack regions, the voltage is increased to ensure sufficient repair energy; when there are fewer regions, the voltage is decreased to avoid excessive impact, optimizing the repair process and improving the efficiency and quality of repair. In addition, this solution also improves the operation convenience. The automatic operation of the controller reduces the manual requirements, while facilitating the monitoring and recording of data, contributing to subsequent maintenance and performance evaluation. It also enhances the versatility and adaptability of the device to photovoltaic power stations of different scales, providing a strong guarantee for improving the overall performance and economic benefits of photovoltaic power stations.

[0015] Optionally, the controller calculates a crack depth value representing the depth of the luminous crack display in the positioning image according to the luminous crack display; According to the number of crack regions and the crack depth value, a comprehensive crack value is calculated by weighted average; the duration of the high-voltage pulse is adjusted in positive correlation with the comprehensive crack value; The larger the comprehensive crack value is, the longer the duration of the high-voltage pulse is; the smaller the comprehensive crack value is, the shorter the duration of the high-voltage pulse is.

[0016] By adopting the above technical solutions, first, this solution further improves the evaluation of cracks in photovoltaic modules and the precise control of repair parameters. The controller can calculate the crack depth value according to the luminous crack display in the positioning image, which provides more in-depth information for the evaluation of the crack situation, not only limited to the number of regions, but also considering the depth of the crack, making the judgment of the crack situation more comprehensive and accurate. By calculating the comprehensive crack value through weighted average by combining the number of crack regions and the crack depth value, a quantitative comprehensive consideration of the crack degree is realized.

[0017] Secondly, adjusting the duration of the high-voltage pulse in positive correlation with the comprehensive crack value can adaptively adjust the repair time required according to the actual severity of the crack. For relatively severe cracks, that is, when the comprehensive crack value is large, the duration of the high-voltage pulse is extended to ensure the repair effect; for relatively minor cracks, that is, when the comprehensive crack value is small, the duration is shortened to avoid excessive impact on the component, thereby improving the refinement and pertinence of the repair process.

[0018] Furthermore, this adjustment method based on the comprehensive crack value helps to improve the repair efficiency. While ensuring the repair quality, it can reduce unnecessary energy consumption, extend the service life of the photovoltaic module, lower the maintenance cost, enabling the photovoltaic module crack repair device to complete the repair work more intelligently, flexibly and efficiently under different crack conditions, and enhancing the overall operation stability and economic benefits of the photovoltaic power station.

[0019] Optionally, the current of the high-voltage pulse is adjusted in positive correlation with the comprehensive crack value; the larger the comprehensive crack value, the larger the current of the high-voltage pulse; the smaller the comprehensive crack value, the smaller the current of the high-voltage pulse.

[0020] By adopting the above technical solution, firstly, the scheme can adjust the current of the high-voltage pulse in positive correlation with the comprehensive crack value, realizing the optimization of the repair process. When the comprehensive crack value is large, the larger current can provide sufficient energy for severe cracks, ensuring that the repair material can fully play its role, improving the repair quality and avoiding repair failure due to insufficient energy; when the comprehensive crack value is small, the smaller current can avoid excessive impact on the photovoltaic module, protect the module performance and extend its service life. Secondly, this adjustment method improves the resource utilization efficiency, avoids energy waste and reduces the operation cost. In addition, it improves the operation convenience and automation level, reduces the complexity of manual operation, is conducive to popularization and use, improves the repair work efficiency and reliability, and at the same time enhances the adaptability of the device, enabling it to flexibly cope with various crack situations and showing better repair performance in photovoltaic power stations of different scales, ensuring the stable operation of the power station.

[0021] Optionally, according to the photovoltaic modules that have been detected in the area where the current photovoltaic module is located, the average crack value of the comprehensive crack value is calculated; according to the average crack value, the voltage value of the high-voltage pulse signal is adjusted when detecting other photovoltaic modules in the current area; the larger the average crack value, the larger the voltage value of the high-voltage pulse signal; the smaller the average crack value, the smaller the voltage value of the high-voltage pulse signal.

[0022] By adopting the above technical solution, firstly, by calculating the average value of the comprehensive crack values of the detected photovoltaic modules, the voltage value of the high-voltage pulse signal can be adjusted according to this information when detecting other photovoltaic modules in the current area. This adjustment method based on the data within the area helps to achieve the overall optimization of the detection and repair of different photovoltaic modules. When the average crack value is large, increasing the voltage value can ensure that the photovoltaic modules to be detected subsequently in the area where the crack situation may be relatively serious obtain sufficient repair energy, improve the success rate of repair, and avoid incomplete repair caused by insufficient voltage. When the average crack value is small, the voltage value is correspondingly reduced to avoid unnecessary energy impact on the photovoltaic modules, protect the module performance, and reduce energy consumption. Secondly, this method can make the detection and repair operations of the photovoltaic modules in the whole area more coordinated and consistent, improve the overall repair efficiency, reduce the repair deviation caused by individual component differences at the same time, and enhance the overall performance and service life of the photovoltaic modules in the area, which has a positive significance for the stable operation and cost control of the photovoltaic power station.

[0023] In summary, the present application includes at least one of the following beneficial technical effects: It can accurately detect the crack problems and occurrence positions of photovoltaic modules. By using a unique detection mechanism, such as the coordinated work of components including a step-down transformer, a step-up transformer, a fault point location film, and a camera device, and the fine analysis of the location image, the crack position can be accurately found, avoiding the inaccuracy of traditional detection methods and providing an accurate information basis for subsequent repair work.

[0024] It can timely detect the problematic modules in a whole string of modules. Through the systematic detection process, not only can the cracked modules be determined, but also the hot spot area and the surface cracking area can be detected simultaneously, comprehensively grasping various problems of the photovoltaic modules, and evaluating the component status more comprehensively and meticulously, which helps to accurately control the overall performance and fault conditions of the photovoltaic power station.

[0025] The cracked area is directly repaired by means of arc heating, and the repair process is efficient and targeted. After determining the crack position, by combining the fault point repair film and adjusting reasonable parameters such as voltage, current, and pulse duration, the electric energy can be effectively used to repair the crack, significantly improving the repair quality and reducing the risk of power generation efficiency decline and component damage caused by cracks.

[0026] Through accurate detection and efficient repair, the benefits of the photovoltaic power station can be greatly improved. It reduces the power generation efficiency loss caused by component cracks and other problems, extends the service life of the photovoltaic modules, reduces the maintenance cost and replacement cost, ensures the stable operation of the photovoltaic power station, and overall improves the economic benefits and operation efficiency of the power station, enabling the photovoltaic power station to continuously and stably output electric energy and providing strong support for the effective utilization of renewable energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a structural diagram when using the fault point location film for detection in the embodiment of the present invention.

[0028] Figure 2 It is a structural diagram when using the fault point repair film for repair in the embodiment of the present invention.

[0029] Figure 3 It is a structural diagram of the fault point location film.

[0030] Figure 4 It is a structural diagram of the fault point repair film.

[0031] Reference signs: 1, step-down transformer; 2, step-up transformer; 3, signal output terminal; 4, test output terminal; 5, fault point location film; 51, positioning flexible substrate; 52, thermochromic coating layer; 53, mixed fluorescent coating layer; 54, positioning conductive coating; 6, fault point repair film; 61, repair flexible substrate; 62, hot melt layer; 63, repair conductive coating; 64, heat preservation layer. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0032] The following details the embodiments of the present application, and the examples of the embodiments are shown in the drawings.

[0033] In the description of this specification, the description with reference to the terms "certain embodiments", "one embodiment", "some embodiments", "schematic embodiments", "examples", "specific examples" or "some examples" means that the specific features, structures, materials or characteristics described in connection with the embodiments or examples are included in at least one embodiment or example of the present application. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiments or examples. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0034] An embodiment of the present application discloses a photovoltaic module crack detection and repair device, referring to Figure 1 and Figure 2 , including a step-down transformer 1, a step-up transformer 2, a fault point location film 5 and a fault point repair film 6.

[0035] Referring to Figure 3, the fault point locating film 5 includes a locating flexible substrate 51, and the outer shape dimensions of the locating flexible substrate 51 are the same as the length and width of the photovoltaic panel to be tested. One side of the locating flexible substrate 51 away from the photovoltaic panel to be tested is the upward surface, and the side close to the photovoltaic panel to be tested is the downward surface. A temperature-sensitive color-changing coating layer 52 is sprayed on one side surface of the locating flexible substrate 51. The temperature-sensitive color-changing coating layer 52 can adopt a reversible temperature-changing coating. When the temperature rises, the color of the coating changes; when the temperature drops, the color returns to its previous state. A mixed fluorescent coating layer 53 containing at least two different wavelength fluorescent powders is sprayed on the other side surface of the locating flexible substrate 51. The two different wavelength fluorescent powders include conversion fluorescent powder and green rare earth fluorescent powder. A locating conductive coating 54 is also sprayed on the side surface of the mixed fluorescent coating layer 53 away from the locating flexible substrate 51; the side of the fault point locating film 5 provided with the locating conductive coating 54 is used for evenly attaching to the light-receiving surface of the photovoltaic panel to be tested. Among them, the locating flexible substrate 51 includes a polyethylene layer, a polypropylene layer, a polyester layer, a polyvinyl chloride layer, a polyimide layer or a polytetrafluoroethylene layer. The locating flexible substrate 51 uses a plastic material as the carrier of the detection film, which not only has good chemical and physical properties, but also can carry key components such as the conductive coating, the mixed fluorescent coating layer 53 and the temperature-sensitive color-changing coating layer 52. The flexibility and weather resistance of the locating flexible substrate 51 ensure that the detection film can be closely attached to the surface of the photovoltaic cell panel, and at the same time can resist the erosion of harsh environmental conditions. In addition, from the perspective of processability, the processability of the locating flexible substrate 51 enables the detection film to be customized according to the actual needs of the photovoltaic cell panel, improving the accuracy and efficiency of detection.

[0036] Among them, the locating conductive coating 54 is, for example, a metal powder layer, and the metal powder particles of the metal powder layer are not larger than 1000 mesh. For metal powder particles not larger than 1000 mesh, their surface area increases, and the contact between particles is closer, thereby improving the electrical conductivity and mechanical properties of the locating conductive coating 54. In addition, the fine particles can also fill the tiny depressions on the surface of the flexible substrate, making the locating conductive coating 54 smoother and flatter.

[0037] Among them, electrostatic flocking is carried out after the spraying processes of the mixed fluorescent coating layer 53 and the metal powder layer are completed. Electrostatic flocking is carried out after the spraying processes of the two coatings are completed, increasing the adhesion and wear resistance of the fault point locating film 5.

[0038] Refer to Figure 4, the fault point repair film 6 includes a repair flexible substrate 61, and the outer dimensions of the repair flexible substrate 61 are the same as the length and width of the photovoltaic panel to be tested. The side of the repair flexible substrate 61 away from the photovoltaic panel to be tested is the upward surface, and the side close to the photovoltaic panel to be tested is the downward surface. A heat insulation layer 64 is provided on one side surface of the repair flexible substrate 61, and the heat insulation layer 64 is formed by uniformly spraying porous heat insulation particles on one side of the repair flexible substrate 61. The heat insulation layer 64 formed by the porous heat insulation particles can play a good heat insulation and heat preservation role during the repair process. There is a hot melt layer 62 on the other side surface of the repair flexible substrate 61, and the hot melt layer 62 is formed by spraying transparent silica gel particles. The transparent silica gel particles can quickly melt under the heating of the electric arc, and have good fluidity, can fully fill the hidden crack area of the photovoltaic module, effectively bridge the crack, prevent the hidden crack from further expanding, ensure the integrity of the module structure, and thus maintain the normal power generation function of the photovoltaic module. A repair conductive coating 63 is provided on the side of the hot melt layer 62 away from the repair flexible substrate 61; among them, the repair conductive coating 63 is formed by uniformly vapor-depositing metal powder on one side of the repair flexible substrate 61, and the metal powder particles of the metal powder layer are not larger than 1000 mesh. The side of the fault point repair film 6 provided with the repair conductive coating 63 is used to be uniformly attached to the light-receiving surface of the photovoltaic panel to be tested. The metal powder has excellent electrical conductivity, and the metal powder layer formed by vapor deposition can efficiently conduct high-voltage pulse signals. When the step-up transformer 2 outputs a high-voltage pulse, the repair conductive coating 63 can ensure that the signal is stably transmitted to the hidden crack of the photovoltaic module, ensure a reliable high-voltage discharge phenomenon at the insulation weak position of the hidden crack, so as to accurately locate the hidden crack part and provide accurate position information for the subsequent repair work.

[0039] Among them, the repair flexible substrate 61 includes a polyethylene layer, a polypropylene layer, a polyester layer, a polyvinyl chloride layer, a polyimide layer or a polytetrafluoroethylene layer. After the two AC power input terminals of the step-down transformer 1 and the step-up transformer 2 are connected in parallel, the two AC power input terminals are connected to the AC power supply; the two power output terminals of the step-down transformer 1 are connected to the positive and negative output terminals of the photovoltaic panel to be tested; one signal output terminal 3 of the step-up transformer 2 is connected to the repair conductive coating 63 of the fault point repair film 6 and the ground terminal, and the other signal output terminal 3 is connected to one of the power output terminals of the step-down transformer 1, and the repair conductive coating 63 of the fault point repair film 6 is connected to the outer frame of the photovoltaic panel to be tested and the ground terminal.

[0040] Step-down transformer 1: An AC adjustable power supply of 0-120V and a current not less than 50A, used to provide stable voltage and current for the photovoltaic panel to be tested. The voltage range of 0-120V can cover the test requirements of most photovoltaic cells and ensure that there will be no excessive voltage impact on the photovoltaic cells during the test.

[0041] Step-up transformer 2: It is a high-voltage AC pulse power supply of 0-10KV, used to generate high-voltage pulses on the fault point positioning film 5, stimulate the phosphor to emit light and detect potential defects. The setting of the current not less than 50A ensures that sufficient current can be provided during the test to stimulate the electroluminescence phenomenon inside the photovoltaic cell, so as to clearly display defects such as hidden cracks.

[0042] Circuit connection of the test circuit: Power input terminal: The power input terminals of step-down transformer 1 and step-up transformer 2 are connected in parallel and connected to the AC mains power supply.

[0043] Power output terminal: The power output terminal of step-down transformer 1 is connected to the positive and negative output terminals of the photovoltaic panel to be tested, used to provide test voltage and current.

[0044] Reference Figure 1 , Signal output terminal 3: One end of signal output terminal 3 of step-up transformer 2 is connected to the fault point positioning film 5 and the grounding terminal, and the other end is connected to a power output terminal (positive or negative) of step-down transformer 1 to form a complete test circuit. Among them, in other embodiments, it can also be that signal output terminal 3 of step-up transformer 2 is connected to the negative pole of the photovoltaic panel to be tested connected to step-down transformer 1.

[0045] Grounding connection: The fault point positioning film 5 is connected to the outer frame of the photovoltaic panel to be tested and the grounding terminal as a whole to ensure safety during the test.

[0046] During high-voltage discharge, heat will be generated in the discharge area. This is because during the discharge process, electrons collide with gas molecules or atoms in solid insulating materials, resulting in energy conversion and local heating. This local heating will increase the temperature of the discharge area, thereby emitting infrared radiation.

[0047] High-voltage discharge will also generate ultraviolet light. When the electric field strength in the insulating layer exceeds a certain threshold, it will trigger gas ionization or local breakdown of solid insulating materials, resulting in discharge. During the discharge process, electrons collide with gas molecules or atoms in solid insulating materials, exciting electrons in atoms or molecules to transition to higher energy levels. When these electrons fall back to lower energy levels, they will release energy, and a part of it is radiated in the form of ultraviolet light.

[0048] The conversion phosphor in the hybrid fluorescent coating layer 53 is a material that can convert light of one wavelength into light of another wavelength. It is usually a compound composed of rare earth elements or other special elements and can emit fluorescence after being excited. The luminescent performance of this phosphor is stable, the color is pure, and the luminous efficiency is high.

[0049] The green rare-earth fluorescent powder in the mixed fluorescent coating layer 53 is a rare-earth material that can emit green fluorescence. It also has stable luminescence performance and high luminescence efficiency. The green rare-earth fluorescent powder has a wide range of applications in the fields of lighting, display, etc. Especially in LED lighting, it can improve the color rendering index and color temperature stability of the light source.

[0050] Fluorescent luminescence principle of operation: When the mixed fluorescent coating layer 53 is excited by an external light source (such as ultraviolet light, visible light, etc.), the conversion fluorescent powder and the green rare-earth fluorescent powder will absorb the excitation light and emit fluorescence. Since the luminescence wavelengths of the two fluorescent powders are different, the fluorescence colors they emit will also be different. By adjusting the ratio of the two fluorescent powders and the wavelength of the excitation light, the luminescence color of the mixed coating can be regulated.

[0051] In summary, the detection principle is as follows: When the fault point location film 5 is evenly attached to the light-receiving surface of the photovoltaic panel to be tested, a current not greater than the set threshold is input from the two power output terminals of the step-down transformer 1 to the positive and negative electrodes of the photovoltaic panel to be tested; after the hot spot damage area on the fault point location film 5 appears, a high-voltage pulse signal is input by the step-up transformer 2 to the positive or negative electrode of the photovoltaic panel to be tested, and a high-voltage discharge occurs at the insulation weak point of the photovoltaic module with a crack; the infrared signal generated by the discharge is changed into a kind of visible light through the fluorescent coating of the first wavelength, and the ultraviolet light generated by the discharge is changed into another kind of visible light through the fluorescent coating of the second wavelength, forming a luminous crack display on the fault point location film 5.

[0052] Using the thermochromic coating layer 52 on the fault point location film 5, the area that may have problems can be initially located according to the appearance of the hot spot damage area on the photovoltaic module. At the same time, by inputting a high-voltage pulse signal through the step-up transformer 2, a high-voltage discharge occurs at the insulation weak point of the crack, and the infrared and ultraviolet signals generated by the discharge can be converted into different visible lights by the fluorescent powders with different wavelengths in the mixed fluorescent coating layer 53, forming a luminous crack display on the location film, realizing the precise visualization of the crack position, overcoming the problem that it is difficult to accurately locate the crack in the traditional detection method, and providing accurate position information for the subsequent repair work.

[0053] The repair principle is as follows: When a luminous crack display is formed on the fault point location film 5, the fault point location film 5 is replaced with the fault point repair film 6; a high-voltage pulse signal is input by the step-up transformer 2 to the positive or negative electrode of the photovoltaic panel to be tested, and a high-voltage discharge occurs at the insulation weak point of the photovoltaic module with a crack, and the hot melt layer 62 melts under the heating of the high-voltage arc and then fills the area of the crack.

[0054] Input a high-voltage pulse signal using a step-up transformer 2 to discharge at the location of the hidden crack, and combine with the repair of the conductive coating of the film 6 at the fault point, which can accurately determine the location of the hidden crack. At the same time, the repair operation can be directly carried out in the photovoltaic module without a complex equipment conversion process, saving time and labor costs, improving the repair efficiency, quickly restoring the performance of the photovoltaic module, and reducing the power generation loss caused by component failure. The heat-melting layer 62 of the fault point repair film 6 melts under the heating of the electric arc to fill the hidden crack area, which can effectively fill the crack, prevent air and moisture from further eroding the internal structure, reduce the risk of oxidation and deterioration of the chip, avoid the generation or deterioration of problems such as hot spots and breakdowns, extend the service life of the photovoltaic module, ensure its long-term stable power generation capacity, and improve the overall reliability and stability of the photovoltaic power generation system. The flexible substrate and the design of each functional layer of the fault point repair film 6 enable it to closely adhere to the light-receiving surface of the photovoltaic panel, ensure good contact between the conductive coating and the photovoltaic module, ensure that the high-voltage pulse signal effectively acts on the hidden crack, and at the same time, the heat-insulating layer 64 helps to maintain an appropriate temperature during the repair process, promotes the heat-melting layer 62 to better play the role of filling and repairing, improves the repair quality, and the connection method of each component is simple and efficient, which is convenient for installation and operation and is conducive to wide application in the actual maintenance of photovoltaic power stations.

[0055] Embodiment 2 The structure of Embodiment 2 is basically the same as that of Embodiment 1, the difference is that Embodiment 2 further includes a camera device, and the camera device is used to take a positioning image of the fault point positioning film 5; the controller identifies the luminous hidden crack display from the positioning image. The controller will screen and analyze the pixel information in the image, and find out the luminous hidden crack display part different from the normal area by identifying specific color, brightness and texture features in the image. These luminous hidden crack displays present a unique luminous pattern, and the controller can accurately distinguish them according to the pre-set image processing algorithm.

[0056] The fault point positioning film 5 is divided into multiple positioning areas, and according to the distribution of the luminous hidden crack display in the multiple positioning areas, the number of positioning areas involved in the luminous hidden crack display is calculated as the number of hidden crack areas.

[0057] Regulate the voltage magnitude of the high-voltage pulse signal in positive correlation with the number of hidden crack areas; the larger the number of hidden crack areas, the higher the voltage of the high-voltage pulse signal; the smaller the number of hidden crack areas, the lower the voltage of the high-voltage pulse signal.

[0058] To more precisely evaluate the situation of hidden cracks, the fault point positioning film 5 is divided into multiple positioning regions. Assuming that the fault point positioning film 5 is divided into 10×10 small square positioning regions of equal area according to a certain grid division method, the light-receiving surface of the entire photovoltaic module can be subdivided into multiple small detection units. Then, according to the distribution of the luminous hidden crack display in these multiple positioning regions, the number of positioning regions involved in the luminous hidden crack display is calculated, and this number is defined as the hidden crack region number.

[0059] The voltage magnitude of the high-voltage pulse signal is adjusted positively correlated with the number of hidden crack regions. When the number of hidden crack regions is small, for example, the luminous hidden crack display only appears in one or two positioning regions, which indicates that the range of hidden cracks is small. At this time, the voltage of the high-voltage pulse signal will be adjusted to a relatively low level, between 2 - 4 kV, which can avoid excessive energy impact on the photovoltaic module and at the same time meet the repair requirements of a small number of hidden crack regions. On the contrary, when the number of hidden crack regions is large, such as more than half of the positioning regions show luminous hidden cracks, it indicates that the hidden crack situation is relatively serious. At this time, the voltage of the high-voltage pulse signal will be increased to 8 - 10 kV to provide sufficient energy to deal with the large-area hidden crack problem.

[0060] The dynamic voltage adjustment mechanism based on the number of hidden crack regions can ensure that at different hidden crack degrees, the most appropriate energy input can be used for repair, avoiding damage to the photovoltaic module or incomplete repair caused by too high or too low voltage, thus ensuring the effectiveness and safety of the hidden crack repair of the photovoltaic module.

[0061] The controller calculates the hidden crack depth value of the depth of the hidden crack shown by the luminous hidden crack display in the positioning image.

[0062] According to the number of hidden crack regions and the hidden crack depth value, a comprehensive hidden crack value is calculated by weighted average; the duration of the high-voltage pulse is adjusted positively correlated with the comprehensive hidden crack value.

[0063] The greater the comprehensive hidden crack value, the longer the duration of the high-voltage pulse; the smaller the comprehensive hidden crack value, the shorter the duration of the high-voltage pulse.

[0064] Based on the luminescent hidden crack display obtained from the positioning image, existing image processing algorithms are used to calculate the hidden crack depth value that represents the depth of the hidden crack in the luminescent hidden crack display. For example, when detecting a photovoltaic module, the controller analyzes the pixel information of the hidden crack area in the positioning image. For different gray levels, the depth of the hidden crack can be determined according to the pre-set mapping relationship between depth and gray level. Suppose in the image, a darker gray area indicates a deeper hidden crack. By accurately measuring the gray value of this area and referring to the depth-gray conversion table, if the depth corresponding to a gray value of 50 is 0.5 mm and the depth corresponding to a gray value of 100 is 0.2 mm, the controller can accurately calculate the corresponding hidden crack depth value.

[0065] The controller performs a weighted average calculation to obtain a comprehensive hidden crack value based on the existing number of hidden crack areas and the calculated hidden crack depth values. Suppose the number of hidden crack areas in a photovoltaic module is 5, and the depth values of each hidden crack area are 0.3 mm, 0.4 mm, 0.2 mm, 0.5 mm, and 0.35 mm respectively, and the weights of the number of hidden crack areas and the hidden crack depth value are 0.4 and 0.6 respectively. Then the comprehensive hidden crack value can be calculated as (5×0.4+(0.3+0.4+0.2+0.5+0.35)×0.6)÷5.

[0066] Regulate the duration of the high-voltage pulse positively correlated with the comprehensive hidden crack value. When the comprehensive hidden crack value is larger, it indicates that the overall situation of the hidden crack is more serious. At this time, the duration of the high-voltage pulse will be correspondingly extended. For example, if the calculated result of the comprehensive hidden crack value is 0.8, the duration of the high-voltage pulse is set to 5 seconds to have sufficient time for the high-voltage pulse to fully play its role in deeper or more hidden crack areas, making the repair process more thorough. On the contrary, when the comprehensive hidden crack value is smaller, such as the calculated result is 0.3, then the duration of the high-voltage pulse will be shortened and set to 1 second to avoid excessive impact on the photovoltaic module and ensure efficient repair work can be completed when the hidden crack is not serious.

[0067] The mechanism of regulating the duration of the high-voltage pulse according to the comprehensive hidden crack value ensures the effectiveness and safety of the repair process. It can reasonably allocate the repair time for different severity levels of hidden crack conditions, avoid energy waste caused by too long a duration or incomplete repair caused by too short a duration, thereby improving the repair quality and overall performance of the photovoltaic module, extending the service life of the photovoltaic module, and ensuring the stable operation of the photovoltaic power station.

[0068] Regulate the current of the high-voltage pulse positively correlated with the comprehensive hidden crack value; the larger the comprehensive hidden crack value, the larger the current of the high-voltage pulse; the smaller the comprehensive hidden crack value, the smaller the current of the high-voltage pulse.

[0069] For example, in a photovoltaic power station, for one of the photovoltaic modules, the comprehensive crack value obtained through a series of detections and calculations is relatively small, such as 0.3. This means that the crack situation of this module is not serious, and there may only be a small number of relatively shallow cracks, which have little impact on the performance of the photovoltaic module. At this time, in order to avoid excessive energy impact on this module and prevent possible damage or other adverse effects, according to the positive correlation adjustment relationship between the comprehensive crack value and the high-voltage pulse current, the current of the high-voltage pulse will be set at a relatively low level, such as 20A. This relatively low current is sufficient to repair the shallow cracks without damaging the module, ensuring the smooth progress of the repair work and also ensuring that the safety and performance of the module are not greatly affected.

[0070] For another photovoltaic module, its comprehensive crack value reaches 0.8, indicating that the crack problem of this module is relatively serious. There may be more crack areas, and the depth of some cracks is relatively deep. In this case, in order to ensure the repair effect, more powerful energy is required to enable the repair material to fully play its role. According to the size of the comprehensive crack value, the current of the high-voltage pulse will be correspondingly increased and adjusted to 80A. Such a relatively high current can provide sufficient energy for the repair process, enabling the repair material to better fill the deeper crack areas under the action of the high-voltage pulse, ensuring that these serious cracks can be fully repaired, avoiding incomplete repair due to insufficient energy, and guaranteeing the power generation efficiency and performance of the photovoltaic module.

[0071] The method of adjusting the high-voltage pulse current according to the comprehensive crack value fully considers the actual crack situation of different photovoltaic modules, avoiding problems that may be caused by a unified current setting. For modules with minor cracks, additional damage will not be caused by excessive current, while for modules with serious cracks, sufficient energy can also be ensured for repair, enabling each module to obtain the most suitable repair conditions according to its own crack situation, thereby improving the repair quality of photovoltaic modules in the entire photovoltaic power station, extending their service life, reducing performance degradation and energy loss caused by cracks, and enhancing the overall power generation efficiency and economic benefits of the power station. At the same time, this adjustment mechanism can also flexibly adjust the repair parameters according to different environmental and usage conditions, adapt to various complex crack situations, and ensure the long-term stable operation of the photovoltaic power station.

[0072] Calculate the average value of the comprehensive crack value based on the photovoltaic modules that have been detected in the area where the current photovoltaic module is located. For example, in a square array area composed of multiple photovoltaic panels, each photovoltaic module has its own comprehensive crack value after careful detection and evaluation. Suppose 10 photovoltaic modules have been detected in this area, and their comprehensive crack values are 0.2, 0.3, 0.4, 0.35, 0.5, 0.25, 0.45, 0.3, 0.4, and 0.38 respectively. Add these comprehensive crack values and divide by the number of modules to calculate the average crack value of 0.358. Adjust the voltage value of the high-voltage pulse signal when detecting other photovoltaic modules in the current area according to the average crack value; the larger the average crack value, the larger the voltage value of the high-voltage pulse signal; the smaller the average crack value, the smaller the voltage value of the high-voltage pulse signal. When this average crack value is relatively large, such as 0.358, it indicates that the overall crack situation of the photovoltaic modules in this area is relatively serious. Then, when detecting other photovoltaic modules, in order to ensure that there is enough energy to deal with possible crack problems, the voltage value of the high-voltage pulse signal will be increased. For example, the voltage value can be adjusted from the original 5 kV to 7 kV or even higher. This is because a higher voltage can provide stronger repair energy for possible deep or large-area cracks, which helps to solve the crack problem more effectively, avoid incomplete repair due to insufficient voltage, and thus ensure the performance and service life of subsequent photovoltaic modules.

[0073] On the contrary, if the average crack value is small, assume that in another area of photovoltaic modules, the calculated average crack value is only 0.15, indicating that the overall crack situation of the photovoltaic modules in this area is relatively light. At this time, when detecting other photovoltaic modules, in order to avoid unnecessary energy impact on the photovoltaic modules, the voltage value of the high-voltage pulse signal will be reduced, for example, from 5 kV to 3 kV. Such a low voltage can avoid excessive energy input while ensuring the completion of crack detection and repair, protect the photovoltaic modules from damage, and at the same time save energy and improve the operation efficiency of the entire photovoltaic power station.

[0074] The method of adjusting the voltage according to the average crack value fully considers the overall crack situation of the photovoltaic modules in the area, realizes overall optimization within the area, ensures that the photovoltaic modules in different areas can obtain appropriate detection and repair conditions according to the actual situation of the area where they are located, improves the efficiency and quality of detection and repair, reduces the decline in power generation efficiency and maintenance costs caused by cracks, and provides a more reliable guarantee for the long-term stable operation of the photovoltaic power station.

[0075] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present application. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present application.

Claims

1. A photovoltaic module hidden crack detection and repair device, characterized in that: It comprises a step-down transformer (1), a step-up transformer (2), a fault point locating film (5) and a fault point repairing film (6); The fault point repair film (6) comprises a repair flexible substrate (61), the other side of the repair flexible substrate (61) has a hot melt layer (62), and the side of the hot melt layer (62) away from the repair flexible substrate (61) is provided with a repair conductive coating (63); the repair conductive coating (63) is used to be evenly applied to the light-receiving surface of the tested photovoltaic panel; After the two AC power input ends of the step-down transformer (1) and the step-up transformer (2) are connected in parallel, the two AC power input ends are connected to the AC power source; the two power output ends of the step-down transformer (1) are connected to the positive and negative output ends of the photovoltaic panel under test; one signal output end (3) of the step-up transformer (2) is connected to the repair conductive coating (63) of the fault point repair film (6) and the ground end, and the other signal output end (3) is connected to one of the power output ends of the step-down transformer (1), and the repair conductive coating (63) of the fault point repair film (6) is connected to the outer frame of the photovoltaic panel under test and the ground end; The fault point positioning film (5) is used to form a luminous hidden crack display. When the luminous hidden crack display is formed on the fault point positioning film (5), the fault point positioning film (5) is replaced by the fault point repair film (6); the step-up transformer (2) inputs a high-voltage pulse signal to the positive or negative electrode of the photovoltaic panel being tested, and high-voltage discharge occurs at the weak insulation point of the photovoltaic component with hidden cracks. The hot melt layer (62) melts under the heating of the high-voltage arc and fills the hidden crack area.

2. The photovoltaic module hidden crack detection and repair device according to claim 1, characterized in that: Transparent silica gel particles are sprayed on a side of the repair flexible substrate (61) away from the thermal insulation layer (64) to form the hot-melt layer (62).

3. The photovoltaic module hidden crack detection and repair device according to claim 1, characterized in that: Metal powder is uniformly vapor-coated on one side of the repair flexible substrate (61) to form the repair conductive coating (63), wherein the metal powder particles of the metal powder layer are not larger than 1000 meshes.

4. The photovoltaic module hidden crack detection and repair device according to claim 1, characterized in that: A heat-insulating layer (64) is provided on one side of the repair flexible substrate (61), and porous heat-insulating particles are evenly sprayed on one side of the repair flexible substrate (61) to form the heat-insulating layer (64).

5. The photovoltaic module hidden crack detection and repair device according to claim 1, characterized in that: The fault point positioning film (5) comprises a positioning flexible substrate (51), one side of the positioning flexible substrate (51) is sprayed with a thermochromic coating layer (52), the other side of the positioning flexible substrate (51) is sprayed with a mixed fluorescent coating layer (53) containing at least two fluorescent powders of different wavelengths, and the side of the mixed fluorescent coating layer (53) away from the positioning flexible substrate (51) is also sprayed with a positioning conductive coating (54); the side of the fault point positioning film (5) provided with the positioning conductive coating (54) is used for being evenly applied to the light-receiving surface of the photovoltaic panel to be tested; When the fault point locating film (5) is evenly applied to the light-receiving surface of the photovoltaic panel being tested, the two power output ends of the step-down transformer (1) input a current not greater than a set threshold value to the positive and negative electrodes of the photovoltaic panel being tested; after the hot spot damage area on the fault point locating film (5) appears, the step-up transformer (2) inputs a high-voltage pulse signal to the positive or negative electrode of the photovoltaic panel being tested, and high-voltage discharge occurs at the weak insulation point where the photovoltaic component is cracked; the infrared signal generated by the discharge is converted into a visible light through a fluorescent coating of a first wavelength, and the ultraviolet light generated by the discharge is converted into another visible light through a fluorescent coating of a second wavelength.

6. The photovoltaic module hidden crack detection and repair device according to claim 5, characterized in that: It also includes a camera device, which is used to capture a positioning image of the fault point positioning film (5); the controller identifies the luminous crack display from the positioning image; The fault point positioning film (5) is divided into a plurality of positioning areas, and according to the distribution of the luminous hidden crack display in the plurality of positioning areas, the number of the positioning areas involved in the luminous hidden crack display is calculated as the number of hidden crack areas; The voltage of the high-voltage pulse signal is adjusted in positive correlation with the number of the hidden crack areas; the larger the number of the hidden crack areas, the larger the voltage of the high-voltage pulse signal; the smaller the number of the hidden crack areas, the smaller the voltage of the high-voltage pulse signal.

7. The photovoltaic module hidden crack detection and repair device according to claim 6, characterized in that: The controller calculates a crack depth value of the crack depth of the luminous crack display according to the luminous crack display in the positioning image; Calculate the comprehensive hidden crack value by weighted average according to the number of hidden crack areas and the hidden crack depth value; Adjusting the duration of the high voltage pulse according to the positive correlation of the comprehensive hidden crack value; The larger the comprehensive hidden crack value is, the longer the duration of the high voltage pulse is; and the smaller the comprehensive hidden crack value is, the shorter the duration of the high voltage pulse is.

8. The photovoltaic module hidden crack detection and repair device according to claim 7, characterized in that: According to the positive correlation of the comprehensive hidden crack value, the current of the high-voltage pulse is adjusted with positive correlation; the larger the comprehensive hidden crack value is, the larger the current of the high-voltage pulse is; the smaller the comprehensive hidden crack value is, the smaller the current of the high-voltage pulse is.

9. The photovoltaic module hidden crack detection and repair device according to claim 7, characterized in that: According to the photovoltaic components that have been detected in the area where the current photovoltaic components are located, the average hidden crack value of the comprehensive hidden crack value is calculated; according to the hidden crack average value, the voltage value of the high-voltage pulse signal when detecting other photovoltaic components in the current area is adjusted; the larger the hidden crack average value, the larger the voltage value of the high-voltage pulse signal; the smaller the hidden crack average value, the smaller the voltage value of the high-voltage pulse signal.

Images