In this paper, we study the application of a non-destructive technique to analyze the argan oil. This is to measure the velocity and attenuation of acoustic waves that propagate in the oil, depending on the temperature and the concentration of other mixtures oils. Information is derived from these measurements find a correlation between measurable parameters and other physical parameters that characterize the liquid. Analytical and empirical models are extracted and studied through these measures. Significant results are presented and discussed to show the interest of the application of this technique on the quality control of this specific oil.
A new approach is presented in this work, to extract electrical parameters of a photovoltaic cell, using the double exponential model. The equivalent circuit parameters of this model are the photocurrent (Iph), ideality factor (?), diffusion current (Iod), recombination current (Ior), series resistance (Rs) and the shunt resistance (Rsh). Several research studies have been performed to extract these parameters. The majority of these developed methods are limited on several levels. In this work the proposed technique is based on the equalization of the electric model of photovoltaic cells, and a polynomial model equivalent. The comparison of these two models at I=0, allows representing the electrical parameters with the polynomial model coefficients. This method is tested on a monocrystalline solar panel and obtained results show the advantage of this technique in level of speed, convergence and precision.
The intrinsic electrical parameters of photovoltaic cells (Rs: series resistance, Rsh: shunt resistance, Iss: the saturation current and ideality factor ?) have a very important role in determining and monitoring the performance of these cells. They help to provide important information on developments or degradation of junctions during electrical operation. They also indicate the intervention limits to replace or repair the PV panels, especially in importance installations. This paper deals a new technique used to improve the quality of the electrical measurements of photovoltaic modules. This method is based on statistical analysis of these measures on two dimensions. The performance of this technique was tested on the P(V) and I (V) characteristics of a PV module. The results show the value of this method because it is able to detect the presence of several types of measurement errors and their origins. A comparison of the results is presented at the end of this work, to show the quality and amount of improvement made by this method on the measurements accuracy of the electrical parameters (Rs, Rsh, ? and Iss).
This work is a contribution in the technical and instrumentation sides related to the field of photovoltaic renewable energy. It presents the details of a simple and low cost electronic realization, capable of increasing the production of photovoltaic electricity. This system is based on an electronic device developed with a microcontroller and other components available on the market. In effect, this electronic card can mechanically control the angular orientations of photovoltaic panels, with actuators connected to a power electronics developed to automatically tracking of the sun position. This system is compared with other fixed photovoltaic system, which was experimentally positioned with optimal physical and geometrical parameters. The results of tests and comparison show the energy benefits and economic and technical interest of this realization.
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