Mesure statistique de la résistance de contact d’une grille sérigraphiée pour cellules solaires au silicium multicristallin

La métallisation par sérigraphie est une des étapes les plus importantes dans la technologie d’élaboration des cellules solaires pour une production à grande échelle. Néanmoins, elle demeure dépendante de plusieurs paramètres variables. Pour le silicium multi cristallin, tout changement dans le procédé de réalisation des cellules solaires influence directement l’optimisation du profil de recuit de la métallisation par sérigraphie. Les plaquettes de silicium multi cristallin subissent toutes les étapes classiques de réalisation des cellules solaires comme le nettoyage chimique et la décontamination, une diffusion au phosphore et le dépôt du nitrure de silicium SiNx par PECVD (Plasma Enhanced Chemical Vapor Deposition). Il y a juste le dépôt du contact Argent Ag sur la face avant de la plaquette. Nous avons utilisé la pâte de sérigraphie Ag Ferro 3349. La grille métallique comporte six (06) motifs TLM (Transfer Length Method) pour les mesures de la résistance de contact. Le principal but de ce travail est le contrôle de la qualité du contact Ag/SiNx/n+-Si dans les cellules solaires au silicium multicristallin. Les mesures TLM révèlent une cartographie des valeurs de la résistance de contact pour chaque température. Le profil optimal de température de recuit est autour de 750 °C

Enhanced performance of optimised partially textured load bearing surfaces

Textured surfaces have been shown to provide enhanced tribological performance in a variety of contacts. Numerical analysis and optimisation methods are combined for application-oriented texture optimisation. However, an analytical approach is advantageous in providing more generic in-depth understanding of the nature of the relationships between texture parameters and objective functions, such as enhanced load carrying capacity and reduced friction. The paper outlines such an approach to obtain a set of global optimum design parameters for partially textured surfaces. The optimised results are expressed in dimensionless form, which enables their use for a variety of applications. The performance of optimised partially textured sliding surfaces is compared with the other conventional bearing geometries in their optimum state

Numerical simulation of silicon based solar cells with a degenerated SnO

The paper presents a numerical simulation of the behaviour of SnO2:F/Si(N+)/Si(P) solar cells. The simulation addresses in particular the question of the role of the window layer SnO2:F for the device performance. As beginning step, the transparent conductive oxide of SnO2:F must be modelled in order to introduce its parameters in simulation codes. Two approaches were employed: one empirical by collecting the experimental data of spray deposited SnO2:F while the second one is theoretical by using models of highly degenerate wide band gap semiconductors. The second step consists in injecting the deduced parameters of fluorine doped tin oxide in simulation codes. We use two well-known photovoltaic simulation codes as PC1D and SCAPS 2.5. A comparative study of the results of structures SnO2:F/Si(N+)/Si(P) and Si(N+)/Si(P) have been done with a confirmation in enhancing the conversion efficiency by SnO2:F window layer addition

SCAPS Simulation for Perovskite Solar Cell

Perovskite solar cells are keeping a very high interest in the solar energy world, with an efficiency in constant rise each year. In this study, we designed a tin-based (Hole Transport Material) HTM perovskite solar cell with the novel architecture Au/CH3NH3SnI3/TiO2/ZnO: Al. A simulation has been carried-out by using the SCAPS-1D solar cell capacitance simulator, which is well adapted to study the solar cell behavior. Through the software tool, we have studied the absorber’s layer thickness effect and the model operating temperature by plugging many varied parameters. The encouraging results of: 20.08% conversion efficiency, 32.76mA/cm² short-circuit current density (Jsc), 0.827 V open circuit voltage (Voc), and a fill factor (FF) of 74.06%, are predicted with the obtained optimal parameters. The results indicate the high aptitude of lead free & HTM perovskite to achieve high efficiency and become a good alternative for the traditional solar cells in the future

Energy Management of a Hybrid Tidal Turbine‐Hydrogen Micro‐Grid: Losses Minimization Strategy

International audienceThis paper presents the modeling and energy management system (EMS) of a hybrid marine‐hydrogen power generation system. The proposed system aims to convert the static nature of the tidal energy into an active system by using a hydrogen energy storage system. The system of the tidal energy converter (TEC) considers the fixed pitch direct drive technology while the hydrogen system consists of 1.0 MW (megawatt) proton exchange membrane electrolyzer. A MATLAB/Simulink based model has been developed for studying and evaluating the effectiveness of the proposed EMS. The developed model depends on scaling up a 50 W proton exchange membrane (PEM) electrolyzer model to 1 MW scale by adapting the model parameters for providing the same key performance indicators (KPIs). The EMS aims to convert all the TEC generated energy into hydrogen with considering the efficient and safe operation of the different system components. Thus, the loss minimization (efficiency maximization) of the tidal turbine generator is integrated as one of the EMS goals to evaluate its effect on hydrogen production. The generator of the TEC is controlled by two different strategies for estimating the surplus hydrogen that could be produced. The strategies are the maximum torque/ampere and the loss minimization