Defect detection and quantification in electroluminescence images of solar PV modules using U-net semantic segmentation

Author(s):  
Lawrence Pratt ◽  
Devashen Govender ◽  
Richard Klein
Sensors ◽  
2021 ◽  
Vol 21 (13) ◽  
pp. 4292
Author(s):  
Horng-Horng Lin ◽  
Harshad Kumar Dandage ◽  
Keh-Moh Lin ◽  
You-Teh Lin ◽  
Yeou-Jiunn Chen

Solar cells may possess defects during the manufacturing process in photovoltaic (PV) industries. To precisely evaluate the effectiveness of solar PV modules, manufacturing defects are required to be identified. Conventional defect inspection in industries mainly depends on manual defect inspection by highly skilled inspectors, which may still give inconsistent, subjective identification results. In order to automatize the visual defect inspection process, an automatic cell segmentation technique and a convolutional neural network (CNN)-based defect detection system with pseudo-colorization of defects is designed in this paper. High-resolution Electroluminescence (EL) images of single-crystalline silicon (sc-Si) solar PV modules are used in our study for the detection of defects and their quality inspection. Firstly, an automatic cell segmentation methodology is developed to extract cells from an EL image. Secondly, defect detection can be actualized by CNN-based defect detector and can be visualized with pseudo-colors. We used contour tracing to accurately localize the panel region and a probabilistic Hough transform to identify gridlines and busbars on the extracted panel region for cell segmentation. A cell-based defect identification system was developed using state-of-the-art deep learning in CNNs. The detected defects are imposed with pseudo-colors for enhancing defect visualization using K-means clustering. Our automatic cell segmentation methodology can segment cells from an EL image in about 2.71 s. The average segmentation errors along the x-direction and y-direction are only 1.6 pixels and 1.4 pixels, respectively. The defect detection approach on segmented cells achieves 99.8% accuracy. Along with defect detection, the defect regions on a cell are furnished with pseudo-colors to enhance the visualization.


Energies ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2308
Author(s):  
Kamran Ali Khan Niazi ◽  
Yongheng Yang ◽  
Tamas Kerekes ◽  
Dezso Sera

Partial shading affects the energy harvested from photovoltaic (PV) modules, leading to a mismatch in PV systems and causing energy losses. For this purpose, differential power processing (DPP) converters are the emerging power electronic-based topologies used to address the mismatch issues. Normally, PV modules are connected in series and DPP converters are used to extract the power from these PV modules by only processing the fraction of power called mismatched power. In this work, a switched-capacitor-inductor (SCL)-based DPP converter is presented, which mitigates the non-ideal conditions in solar PV systems. A proposed SCL-based DPP technique utilizes a simple control strategy to extract the maximum power from the partially shaded PV modules by only processing a fraction of the power. Furthermore, an operational principle and loss analysis for the proposed converter is presented. The proposed topology is examined and compared with the traditional bypass diode technique through simulations and experimental tests. The efficiency of the proposed DPP is validated by the experiment and simulation. The results demonstrate the performance in terms of higher energy yield without bypassing the low-producing PV module by using a simple control. The results indicate that achieved efficiency is higher than 98% under severe mismatch (higher than 50%).


Smart Science ◽  
2021 ◽  
pp. 1-12
Author(s):  
Mohd Tariq ◽  
Mohsin Karim Ansari ◽  
Fazlur Rahman ◽  
Md Atiqur Rahman ◽  
Imtiaz Ashraf
Keyword(s):  
Solar Pv ◽  

2013 ◽  
Vol 2013 ◽  
pp. 1-13 ◽  
Author(s):  
Diego Torres Lobera ◽  
Anssi Mäki ◽  
Juha Huusari ◽  
Kari Lappalainen ◽  
Teuvo Suntio ◽  
...  

A grid connected solar photovoltaic (PV) research facility equipped with comprehensive climatic and electric measuring systems has been designed and built in the Department of Electrical Engineering of the Tampere University of Technology (TUT). The climatic measuring system is composed of an accurate weather station, solar radiation measurements, and a mesh of irradiance and PV module temperature measurements located throughout the solar PV facility. Furthermore, electrical measurements can be taken from single PV modules and strings of modules synchronized with the climatic data. All measured parameters are sampled continuously at 10 Hz with a data-acquisition system based on swappable I/O card technology and stored in a database for later analysis. The used sampling frequency was defined by thorough analyses of the PV system time dependence. Climatic and electrical measurements of the first operation year of the research facility are analyzed in this paper. Moreover, operation of PV systems under partial shading conditions caused by snow and building structures is studied by means of the measured current and power characteristics of PV modules and strings.


2021 ◽  
Vol 11 (22) ◽  
pp. 10508
Author(s):  
Chaowei Tang ◽  
Xinxin Feng ◽  
Haotian Wen ◽  
Xu Zhou ◽  
Yanqing Shao ◽  
...  

Surface defect detection of an automobile wheel hub is important to the automobile industry because these defects directly affect the safety and appearance of automobiles. At present, surface defect detection networks based on convolutional neural network use many pooling layers when extracting features, reducing the spatial resolution of features and preventing the accurate detection of the boundary of defects. On the basis of DeepLab v3+, we propose a semantic segmentation network for the surface defect detection of an automobile wheel hub. To solve the gridding effect of atrous convolution, the high-resolution network (HRNet) is used as the backbone network to extract high-resolution features, and the multi-scale features extracted by the Atrous Spatial Pyramid Pooling (ASPP) of DeepLab v3+ are superimposed. On the basis of the optical flow, we decouple the body and edge features of the defects to accurately detect the boundary of defects. Furthermore, in the upsampling process, a decoder can accurately obtain detection results by fusing the body, edge, and multi-scale features. We use supervised training to optimize these features. Experimental results on four defect datasets (i.e., wheels, magnetic tiles, fabrics, and welds) show that the proposed network has better F1 score, average precision, and intersection over union than SegNet, Unet, and DeepLab v3+, proving that the proposed network is effective for different defect detection scenarios.


2019 ◽  
Vol 9 ◽  
pp. 59-69
Author(s):  
Alok Dhaundiyal ◽  
Divine Atsu

This paper presents the modeling and simulation of the characteristics and electrical performance of photovoltaic (PV) solar modules. Genetic coding is applied to obtain the optimized values of parameters within the constraint limit using the software MATLAB. A single diode model is proposed, considering the series and shunt resistances, to study the impact of solar irradiance and temperature on the power-voltage (P-V) and current-voltage (I-V) characteristics and predict the output of solar PV modules. The validation of the model under the standard test conditions (STC) and different values of temperature and insolation is performed, as well as an evaluation using experimentally obtained data from outdoor operating PV modules. The obtained results are also subjected to comply with the manufacturer’s data to ensure that the proposed model does not violate the prescribed tolerance range. The range of variation in current and voltage lies in the domain of 8.21 – 8.5 A and 22 – 23 V, respectively; while the predicted solutions for current and voltage vary from 8.28 – 8.68 A and 23.79 – 24.44 V, respectively. The measured experimental power of the PV module estimated to be 148 – 152 W is predicted from the mathematical model and the obtained values of simulated solution are in the domain of 149 – 157 W. The proposed scheme was found to be very effective at determining the influence of input factors on the modules, which is difficult to determine through experimental means.


2021 ◽  
pp. 265-291
Author(s):  
Saji Chacko ◽  
R. N. Patel ◽  
Ramesh C. Bansal
Keyword(s):  
Solar Pv ◽  

Author(s):  
Sivaraman P. ◽  
Sharmeela C.

A solar micro inverter is a small-size inverter designed for single solar PV module instead of group of solar PV modules. Each module is equipped with a micro inverter to convert the DC electricity into AC electricity and the micro inverter is placed/installed below the module. The advantages of micro inverters are: reduced effect of shading losses, module degradation and soiling losses, enabled module independence, different rating of micro inverter can be connected in parallel to achieve the desired capacity, additional modules can be included at time which allows the good scalability, string design and sizing are avoided, failure of any micro inverter does not affect the overall power generation, individual MPPT controller for each module increases the power generation, any orientation and tilt angle allows higher design flexibility, lower DC voltage increasing the safety, easy to design, handle and install, requires less maintenance, draws attention of design engineers, contractors, etc.


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