Electroluminescence Imaging for Microcrack Detection in Solar Cells

High-precision photovoltaic module EL detection method and system for accurate monitoring of photovoltaic modules. The method employs voltage excitation of the photovoltaic component, followed by photodetector-based voltage measurement. The system employs precise control of the excitation voltage to optimize detection performance, particularly for modules operating near their maximum power point. This approach enables the detection of subtle defects such as micro-cracks and localized heating through advanced signal processing and analysis.

Source

Solar photovoltaic power generation component fault detection system that enables real-time monitoring of cracks and hot spots in solar panels through automated, remote detection. The system comprises a photovoltaic panel frame assembly with a counterweight, position adjustment mechanism, EL detector, infrared thermal imager, and a photovoltaic power generation component fault detection system. The system's position adjustment mechanism enables precise positioning of the EL detector and infrared thermal imager within the protective enclosure, while the photovoltaic power generation component fault detection system monitors panel performance and detects faults through advanced thermal imaging.

Source

Photovoltaic cell fault detection using a modulated light matrix approach. The method involves generating modulated light signals at different frequencies to each photovoltaic cell, then superimposing these signals to form a total short-circuit current. By analyzing the amplitude of the generated photocurrents, the method can determine the presence and location of faults in individual cells, including cracking, contact resistance issues, and internal resistance variations. This approach enables precise fault location and characterization through the unique spectral signatures of each cell.

Source

A method for improving the detection of solar cell defects through enhanced electroluminescence analysis. The method employs segmented probe rows with fixed resistive values between 0.1-100Ω, with the far end connected to the power supply. Each row of segmented probes is connected to the main grid, while the far end of the fixed resistor is connected to the solar cell. This configuration enables the detection of internal defects by analyzing the current distribution across the solar cell when the external current is zero.

Source

Improving power-on uniformity in photovoltaic cell EL detection through a novel method. The method involves connecting the two ends of each welding strip to a fixed resistance resistor, then applying DC power to the strips. This configuration eliminates the conventional soldering contact issues by mechanically connecting the ends of the strips to a fixed point, ensuring consistent resistance values across the string. This approach eliminates the variability associated with soldering and flux buildup, resulting in more uniform EL imaging across the cell string.

Source

A camera system for diagnosing solar cell defects through direct imaging of electric field emission. The system employs a high-pass filter to selectively transmit wavelengths above 700 nm, allowing detailed imaging of the solar cell's internal structure while suppressing visible light. The system features a low-pass filter to remove visible light, enabling precise imaging of the electric field emission patterns. The camera system can capture both static and dynamic images of the solar cell, enabling rapid defect detection and characterization.

Source

Power supply device for solar cell inspection using EL imaging, which eliminates the need for a diesel generator. The device converts the solar cell module's DC output into a direct current (DC) using a power conditioner, and then supplies the DC current to an imaging device for EL imaging. The imaging device captures EL light emission from the solar cell module, which is then used to generate images for quality inspection. The power conditioner ensures reliable DC output from the solar cell module, eliminating the need for an external power source.

Source

FPGA-based system for on-site EL video image detection of photovoltaic components and automatic defect identification. The system enables real-time monitoring of photovoltaic modules through EL imaging, eliminating the need for manual inspection. The system employs a portable EL camera to capture images of photovoltaic modules, which are then processed using an FPGA to detect defects such as cracks and fragments. The system's automated detection capabilities enable rapid and accurate identification of defects in real-time, while eliminating the time-consuming and labor-intensive process of traditional EL inspection.

Source

System and method for inspecting solar panels using high-power UV light sources that enables non-destructive defect detection through fluorescence imaging. The system comprises a high-power UV light source coupled with an imaging device, where the exposure time is synchronized with the imaging device's shutter speed. The UV light source emits high-intensity UV radiation to the solar panel, while the imaging device captures fluorescence images of the panel's surface. The synchronized exposure enables precise imaging of fluorescence patterns indicative of defects, such as cracks, without requiring direct electrical contact.

Source

Real-time online monitoring of photovoltaic cell modules using drone-based EL imaging and analysis. The method enables continuous, automated detection of module faults through EL imaging, which is performed by deploying a drone equipped with a camera system. The drone captures images of the photovoltaic cells in their active state, allowing for precise EL analysis. The system automatically identifies and diagnoses faults, enabling real-time maintenance and predictive maintenance through its comprehensive EL monitoring capabilities.

Source

A diagnostic system for solar cell modules that enables accurate identification of deterioration through non-destructive testing. The system employs a near-infrared camera to capture images of the solar cell module's electroluminescence emission patterns. This image analysis is performed using computer algorithms that correlate the intensity of the emitted light with the degree of module degradation. The system can operate from ground or aerial platforms, allowing for comprehensive inspection of large-scale solar arrays. The diagnostic process eliminates the need for traditional failure location identification methods, enabling rapid and accurate identification of module deterioration without requiring physical access.

Source

Detecting mechanical defects in semiconductor devices, particularly solar cells, through automated optical inspection of their radiation behavior. The method employs a forward-biased pn junction with controlled voltage application, followed by selective optical detection of radiation patterns in the semiconductor layer. The detection process monitors both active and inactive regions of the semiconductor for abrupt, one-dimensional intensity changes, automatically identifying defects. This approach enables precise defect characterization in indirect bandgap semiconductors like silicon-based solar cells.

Source

Enhancing surface inspection of photovoltaic modules through infrared camera-based EL detection. The method utilizes an infrared camera to monitor component integrity during installation or arrival, employing a systematic approach to ensure comprehensive coverage. The camera is positioned to capture images of the module's surface from multiple angles, with a minimum camera-to-component distance of 1.6 meters. This approach provides detailed images of components such as cracks, fragments, broken grids, and bright/dark films, enabling accurate detection and quality control during the installation process.

Source

System for inspecting and monitoring photovoltaic modules through advanced imaging techniques. The system employs scanning mechanisms to capture detailed images of module surfaces, employing techniques like electroluminescence imaging, photoluminescence imaging, and thermal imaging. The system's processing capabilities analyze these images to identify defects, cracks, and other performance issues, providing detailed insights into module condition. The system enables continuous monitoring throughout the module's lifespan, from manufacturing to service, through automated image acquisition and analysis.

Source

Apparatus and method for inspecting solar cell modules using phase-locked light emission imaging. The method employs a solar cell module with a power device that generates a constant voltage waveform when exposed to sunlight, capturing images of the resulting electroluminescence at a specific cycle. The captured images are then processed using a weighting function that introduces phase changes, effectively creating a phase-locked emission image. The method extracts the image with the greatest contrast, which represents the most characteristic feature of the solar cell.

Source

A solar cell inspection device that enables rapid and accurate detection of defects in solar panels using electroluminescence (EL) technology. The device employs a high-power AC power source to generate electrical current across the solar panel, inducing EL emission through semiconductor defects. The inspection process is performed in situ, eliminating the need for specialized equipment or preparation. The device's configuration allows for continuous inspection of solar panels in various environments, including outdoor conditions, while maintaining precise control over the inspection process.

Source

Detecting cracks in solar panels through electrical current flow analysis. The method involves capturing images of the panel under current flow conditions, then using image processing to identify regions of reduced current flow indicative of cracks. By analyzing the current flow patterns through the panel, the method can detect cracks that would otherwise be difficult to identify through visual inspection alone.

Source

A system for inspecting photovoltaic modules using luminescence imaging techniques to detect defects and condition deterioration. The system employs a power supply and detector to generate electroluminescence from the module, while a scanning mechanism applies electrical excitation to scan the module. The system captures images of the generated electroluminescence, enabling the detection of defects such as cracks, shunts, and contact pattern defects. The images can be processed using advanced algorithms to distinguish between different types of defects, calculate defect metrics, and provide detailed condition assessments. The system can also incorporate temperature monitoring and compare images from different scanning positions to enhance defect detection.

Source

Diagnostic system for solar cell modules that enables precise location-based failure detection through non-invasive imaging and analysis. The system employs a network of solar cells connected in series, with an integrated camera system capturing near-infrared light emission patterns. A constant power supply device and image processing computer combine these signals to identify deterioration patterns, enabling location-specific failure diagnosis without requiring access to the solar cell array. The system can operate from remote locations, such as unmanned aerial vehicles, and provides detailed diagnostic information through machine learning algorithms.

Source

Detecting black spot defects in solar cell EL images using a region growing algorithm that improves accuracy through adaptive segmentation, connected domain analysis, and texture analysis. The method extracts a region of interest from the EL image, performs region growing to identify potential defects, and employs connected domain analysis to exclude non-defect regions. The approach further employs texture analysis to detect defects through image feature extraction and curve detection.

Source