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The purpose of this study was the comparison and analysis of the electrical parameters of two kinds of silicon solar cells (mono- and multicrystalline) of different emitter resistance.

By controlling of diffusion parameters, silicon mono- (Cz-Si) and multicrystalline (mc-Si) solar cells with different emitter resistance values were produced – 22 and 48 Ω/□. On the basis of current-voltage measurements of cells and contact resistance mapping, the properties of final solar cells based on two different materials were compared. Additionally, the influence of temperature on PV cells efficiency and open circuit voltage (U_oc) were investigated. The PC1D simulation was useful to determine spectral dependence of external quantum efficiency of solar cells with different emitter resistance. The silicon solar cells of 25 cm² area and 240 µm thickness were investigated.

Considering the all stages of cell technology, the best structure is silicon solar cell with sheet resistance (R_sheet) of 45-48 Ω/□. Producing of an emitter with this resistance allowed to obtain cells with a fill factor between 0.725 and 0.758, U_oc between 585 and 612 mV, short circuit current (I_sc) between 724 and 820 mA.

Measurements and analysis confirmed that mono- and multicrystalline silicon solar cells with 48 Ω/□ emitter resistance have better parameters than cells with R_sheet of 22 Ω/□. The contact resistance is the highest for mc-Si with R_sheet of 48 Ω/□ and reaches the value 3.8 Ωcm.

This paper aims to improve the generalization capability of feature extraction scheme by introducing a micro-cracks detection method based on self-learning features. Micro-cracks detection of multicrystalline solar cell surface based on machine vision is fast, economical, intelligent and easier for on-line detection. However, the generalization capability of feature extraction scheme adopted by existed methods is limited, which has become an obstacle for further improving the detection accuracy.

A novel micro-cracks detection method based on self-learning features and low-rank matrix recovery is proposed in this paper. First, the input image is preprocessed to suppress the noises and remove the busbars and fingers. Second, a self-learning feature extraction scheme in which the feature extraction templates are changed along with the input image is introduced. Third, the low-rank matrix recovery is applied to the decomposition of self-learning feature matrix for obtaining the preliminary detection result. Fourth, the preliminary detection result is optimized by incorporating the superpixel segmentation. Finally, the optimized result is further fine-tuned by morphological postprocessing.

Comprehensive evaluations are implemented on a data set which includes 120 testing images and corresponding human-annotated ground truth. Specifically, subjective evaluations show that the shape of detected micro-cracks is similar to the ground truth, and objective evaluations demonstrate that the proposed method has a high detection accuracy.

First, a self-learning feature extraction method which has good generalization capability is proposed. Second, the low-rank matrix recovery is combined with superpixel segmentation for locating the defective regions.

In this paper, we aim to investigate the influence of the hydrogenated silicon nitride layers deposited by a large area 13.56 MHz plasma-enhanced chemical vapour deposition system on the electrical activity of the surface and interfaces of the grains for solar cells fabricated on microcrystalline silicon and multicrystalline silicon.

The characterization of current-voltage parameters of 25 cm² solar cells manufactured with different passivation and antireflective layers are presented. After spectral response measurements, external quantum efficiency was calculated, and the final results are shown graphically. The passivation effect concerning grain areas was evaluated more precisely by light-beam-induced current scan maps (LBIC).

The final impact of the type of passivation layer on surface and grain boundary photoconvertion in solar cells is determined.

The passivation effect concerning grain areas was evaluated more precisely by LBIC.

The purpose of this study is to address the issue of technology equipment formerly dedicated to the process of 4- and even 5-inch photovoltaic cells and whose use has become critical with the evolution of silicon wafer size standards (M2–M10). Fortunately, the recent concept of 6'' half-cut cell with its many advantages appears promising insofar as it offers the possibility of further extend the use of costly, still operational process equipment, but doomed to obsolescence.

In the background of a detailed Al-BSF process, the authors show how to experimentally adapt specific accessories and arrange 6” half-wafers to enable the upgrade of a complete industrial process of silicon solar cells at a lower cost. Step by step, the implementation of the processes for the two wafer sizes (4” wafers and 6” half wafers) is compared and analyzed in terms of performance and throughput.

Globally, the same process effectiveness is observed for both types of wafers with slightly better sheet resistance uniformity for the thermal diffusion carried out on the half wafers; however, the horizontal arrangement of the wafer carriers in the diffusion and the plasma-enhanced chemical vapor deposition tubes limits the thermal balance regarding the total number of cells processed per batch.

In terms of the development of prototypes on a preindustrial scale, this paves the way to further continue operating outdated equipment for high-performance processes (passivated emitter and rear contact, Tunnel oxide passivated contact (TOPCon)), while complying with current standards for silicon wafers up to M10 format.

Estimation of solar cell parameters, mathematical modeling and the actual performance analysis of photovoltaic (PV) cells at various ecological conditions are very important in the design and analysis of maximum power point trackers and power converters. This study aims to propose the analysis and modeling of a simplified three-diode model based on the manufacturer’s performance data.

A novel technique is presented to evaluate the PV cell constraints and simplify the existing equation using analytical and iterative methods. To examine the current equation, this study focuses on three crucial operational points: open circuit, short circuit and maximum operating points. The number of parameters needed to estimate these built-in models is decreased from nine to five by an effective iteration method, considerably reducing computational requirements.

The proposed model, in contrast to the previous complex nine-parameter three-diode model, simplifies the modeling and analysis process by requiring only five parameters. To ensure the reliability and accuracy of this proposed model, its results were carefully compared with datasheet values under standard test conditions (STC). This model was implemented using MATLAB/Simulink and validated using a polycrystalline solar cell under STC conditions.

The proposed three-diode model clearly outperforms the earlier existing two-diode model in terms of accuracy and performance, especially in lower irradiance settings, according to the results and comparison analysis.

The purpose of this paper is to discuss the effect of electric reverse stress currents on the performance of photovoltaic solar modules.

The effect of a reverse introduced current as a function of time is studied on the I‐V and C‐V characteristics and parameters which were extracted and analyzed using numerical analysis based on a reliable double exponential model.

The effect of an introduced reverse current for different periods simulated the effect of accumulated extreme reverse currents which may arise in solar cells and modules due to different reasons, causing dramatic changes in the shunt resistance as well as other characteristics, mainly when the time of the current application exceeded a certain limit.

The paper contributes to the research on the damaging effects of reverse currents on the normal operation of the solar cells and modules.

The purpose of this paper is to investigate the dark properties as a function of reverse current induced defects. Dark characteristics of solar modules are very essential in the understanding the functioning of these devices.

Reverse currents were applied on the photovoltaic (PV) modules to create defects. At several time intervals, dark characteristics along with surface temperature were measured.

Current-voltage (I-V) and capacitance-voltage (C-V) characteristics furnished valuable data and threshold values for reverse currents. Maximum module surface temperatures were directly related to each of the induced reverse currents and to the amount of leakage current. Microstructural damages, in the form of hot spots and overheating, are linked to reverse current effects. Experimental evidence showed that different levels of reverse currents are a major degrading factor of the performance of solar cells and modules.

These results give a reliable method to predict most of the essential characteristics of a silicon solar cell or a module. Similar test could help predict the amount of degradation or even the failure of PV modules.

Tunisia has high solar radiation levels, which makes it suitable for the installation of photovoltaic (PV) systems. The design of these kinds of systems is an important step because there are many crucial factors to assess the PV module efficiency such as temperature, module types and solar radiation.This paper aims to give an analysis of the most influencing factor for selecting location. In fact, after estimating the PV panel inclination, the solar radiation and the temperature in “Zarzis” (southeastern of Tunisia), a comparative analysis among the different PV panel types was given. Additionally, to find which technologies are suitable for the climate conditions of this area, it is important to compare the effect of temperature and solar radiation on their performances.

Different techniques applied for the fabrication of thick‐film fine lines have been analysed. The basics, achievements, advantages and disadvantages of improved screen printing, screen printing with metal masks, the direct writing method, offset printing and photoformed or photoetched thick‐film are presented. In addition, current trends in front metallisation of silicon solar cells are described. Based on a critical review, the use of thick‐film fine lines for this purpose is discussed.

The purpose of this paper was investigation and comparison of electrical and optical properties of crystalline silicon solar cells with ITO or TiO₂ coating. The ITO, similar to TiO₂, is very well transparent in the visible part of optical radiation; however, its low resistivity (lower that 10-3 Ohm/cm) makes it possible to use simultaneously as a transparent electrode for collection of photo-generated electrical charge carriers. This might also invoke increasing the distance between screen-printed metal fingers at the front of the solar cell that would increase of the cell’s active area. Performed optical investigation showed that applied ITO thin film fulfill standard requirements according to antireflection properties when it was deposited on the surface of silicon solar cell.

Two sets of samples were prepared for comparison. In the first one, the ITO thin film was deposited directly on the crystalline silicon substrate with highly doped emitter region. In the second case, the TCO film was deposited on the same type of silicon substrate but with additional ultrathin SiO₂ passivation. The fingers lines of 80 μm width were then screen-printed on the ITO layer with two different spaces between fingers for each set. The influence of application of the ITO electrode and the type of metal electrodes patterns on the electrical performance of the prepared solar cells was investigated through optical and electrical measurements.

The electrical parameters such as short-circuit current (J_sc), open circuit voltage (Voc), fill factor (FF) and conversion efficiency were determined on a basis of I-V characteristics. Short-circuit current density (J_sc) was equal to 32 mA/cm² for a solar cell with a typical antireflection layer and 31.5 mA/cm² for the cell with ITO layer, respectively. Additionally, electroluminescence of prepared cells was measured and analysed.

The influence of the properties of ITO electrode on the electrical performance of crystalline silicon solar cells was investigated through complex optical, electrical and electroluminescence measurements.