Power Quality Enhancement in Hybrid Photovoltaic-Battery System based on three–Level Inverter associated with DC bus Voltage Control

This modest paper presents a study on the energy quality produced by a hybrid system consisting of a Photovoltaic (PV) power source connected to a battery. A three-level inverter was used in the system studied for the purpose of improving the quality of energy injected into the grid and decreasing the Total Harmonic Distortion (THD). A Maximum Power Point Tracking (MPPT) algorithm based on a Fuzzy Logic Controller (FLC) is used for the purpose of ensuring optimal production of photovoltaic energy. In addition, another FLC controller is used to ensure DC bus stabilization. The considered system was implemented in the Matlab /SimPowerSystems environment. The results show the effectiveness of the proposed inverter at three levels in improving the quality of energy injected from the system into the grid.Peer reviewedFinal Published versio

Tuberculose multifocale révélée par une pancytopénie: à propos d’un cas

Patiente de 58 ans, admise dans un tableau de polypnée avec signes de lutte respiratoire et désaturant à 65% à l’air ambiant et une fièvre à 38,5°C, l’hémogramme trouve une pancytopénie, l’ionogramme objctive une légère cytolyse hépatique et la radio des poumons objective un aspect de miliaire bilatérale. Les recherches de BK dans les expectorations étaient négatives ainsi que le Gene Xpert. L’étude anatomo-pathologique de la biopsie ostéomédullaire montre un granulome épithélio-giganto-cellulaire sans nécrose caséeuse et la PCR met en évidence le mycobacterium tuberculosis dans le prélèvement de biopsie ostéo-médullaire. Une biopsie hépatique a mis en évidence un granulome épithélioïde sans nécrose caséeuse. Le diagnostic de tuberculose multifocale avec atteinte pulmonaire, hématopoïétique et hépatique était retenu. La miliaire tuberculeuse est l’une des atteintes sévères dans le cadre de la tuberculose, les bacilloscopies sont souvent négatives et le diagnostic peut être retenu par d’autres prélèvements notamment l’étude du liquide céphalo-rachidien et la biopsie ostéomédullaire. La biopsie d’autres organes peut apporter le diagnostic dans de rares cas. L’avènement de la PCR comme technique de biologie moléculaire a permis de raccourcir le délai de diagnostic et donc la mise en route du traitement qui parfois doit être administré avant même d’obtenir la certitude diagnostique compte tenu de la mise en jeu du pronostic vital au cours de ces atteintes sévères

Tumeur d’Abrikossoff à localisation gastrique: à propos d’un nouveau cas

Les tumeurs à cellules granuleuses (TCG) sont des tumeurs peu fréquentes. Elles sont localisées préférentiellement eu niveau de la peau et des tissus sous-cutanés. La localisation gastrique reste rare. A un nouveau cas de tumeur d'Abrikossoff à localisation gastrique ainsi qu'une brève revue de la littérature, on se propose d'étudier les particularités cliniques, endoscopiques et thérapeutiques de cette entité rare.Mots clés: Tumeurs à cellules granuleuses, résection endoscopique, tumeur d´AbrikossoffEnglish Title: Gastric Abrikossoff tumor: about a new caseEnglish AbstractGranular cell tumors (GCT) are uncommon tumors. They mainly occur at the level of the skin and the subcutaneous tissues. Gastric tumor is rare. We here report a new case of gastric Abrikossoff tumor as well as a brief literature review. This study aims to examine the clinical, endoscopic and therapeutic features of this rare disease.Keywords: Granular cell tumors, endoscopic resection, Abrikossoff tumo

A degenerate Kirchhoff-type problem involving variable s(⋅)s(\cdot)-order fractional p(⋅)p(\cdot)-Laplacian with weights

This paper deals with a class of nonlocal variable $s(.)$-order fractional $p(.)$-Kirchhoff type equations: \begin{eqnarray*} \left\{ \begin{array}{ll} \mathcal{K}\left(\int_{\mathbb{R}^{2N}}\frac{1}{p(x,y)}\frac{|\varphi(x)-\varphi(y)|^{p(x,y)}}{|x-y|^{N+s(x,y){p(x,y)}}} \,dx\,dy\right)(-\Delta)^{s(\cdot)}_{p(\cdot)}\varphi(x) =f(x,\varphi) \quad \mbox{in }\Omega, \\ \varphi=0 \quad \mbox{on }\mathbb{R}^N\backslash\Omega. \end{array} \right. \end{eqnarray*} Under some suitable conditions on the functions $p,s, \mathcal{K}$ and $f$, the existence and multiplicity of nontrivial solutions for the above problem are obtained. Our results cover the degenerate case in the $p(\cdot)$ fractional setting

A new class of multiple nonlocal problems with two parameters and variable-order fractional p(⋅)p(\cdot)-Laplacian

In the present manuscript, we focus on a novel tri-nonlocal Kirchhoff problem, which involves the $p(x)$-fractional Laplacian equations of variable order. The problem is stated as follows: \begin{eqnarray*} \left\{ \begin{array}{ll} M\Big(\sigma_{p(x,y)}(u)\Big)(-\Delta)^{s(\cdot)}_{p(\cdot)}u(x) =\lambda |u|^{q(x)-2}u\left(\int_\O\frac{1}{q(x)} |u|^{q(x)}dx \right)^{k_1}+\beta|u|^{r(x)-2}u\left(\int_\O\frac{1}{r(x)} |u|^{r(x)}dx \right)^{k_2} \quad \mbox{in }\Omega, \\ u=0 \quad \mbox{on }\partial\Omega, \end{array} \right. \end{eqnarray*} where the nonlocal term is defined as $$\sigma_{p(x,y)}(u)=\int_{\Omega\times \Omega}\frac{1}{p(x,y)}\frac{|u(x)-u(y)|^{p(x,y)}}{|x-y|^{N+s(x,y)p(x,y)}} \,dx\,dy.$$ Here, $\Omega\subset\mathbb{R}^{N}$ represents a bounded smooth domain with at least $N\geq2$. The function $M(s)$ is given by $M(s) = a - bs^\gamma$, where $a\geq 0$, $b>0$, and $\gamma>0$. The parameters $k_1$, $k_2$, $\lambda$ and $\beta$ are real parameters, while the variables $p(x)$, $s(\cdot)$, $q(x)$, and $r(x)$ are continuous and can change with respect to $x$. To tackle this problem, we employ some new methods and variational approaches along with two specific methods, namely the Fountain theorem and the symmetric Mountain Pass theorem. By utilizing these techniques, we establish the existence and multiplicity of solutions for this problem separately in two distinct cases: when $a>0$ and when $a=0$. To the best of our knowledge, these results are the first contributions to research on the variable-order $p(x)$-fractional Laplacian operator.Comment: 21 page

Fuzzy Control of a Three-Phase Shunt Active Filter for Harmonic Current Compensation in Wind-Diesel Standalone System

Mohamed AbdeldjabbarKouadria, TayebAllaoui, and Mouloud Denai, “Fuzzy Control of a Three-Phase Shunt Active Filter for Harmonic Current Compensation in Wind-Diesel Standalone System”, U.P.B. Sci. Bull., Series C, Vol. 78 (4), 2016.This paper presents the design of a fuzzy controller for a three-phase shunt active filter integrated in wind-diesel power system equipped with a wind turbine driving an induction generator. The goal for this controller is to maintain a good power quality under varying wind and load conditions. On the other hand, the controller should show acceptable closed-loop performance including stability and robustness. Active power filters as solutions to power quality problems have become more and more important nowadays. The modeling of the wind-diesel standalone system with control algorithm of the shunt active power filter (SAPF) to compensate the current harmonics and the power factor of nonlinear load is considered. A threephase voltage source bridge inverter with a DC bus capacitor is used as an active filter.Peer reviewe

Combining Multi-Band Power System Stabilizers and Hybrid Power Flow Controllers to Support Electricity Grids with High Penetration of Distributed Renewable Generation

The paper demonstrates the application of a new power flow configuration consisting of a Hybrid Power Flow Controller (HPFC) and a Multi-Band Power System Stabilizers (MB-PSS) to enhance the performance of a multi-machine power network in the presence of solar photovoltaic (PV) and wind energy sources. The HPFC is a new type of FACTS (Flexible AC Transmission Systems) device, which has been introduced to address inter-area congestion problems by controlling the real power flow and providing voltage regulation. The MB-PSS, on the other hand, is a power system stabilizer based on different frequency modes of electromechanical oscillations, where the discontinuities caused by the faults in the grid are taken in consideration, for multiple fault clearing times.The multi-machine power network with PV and wind distributed generation and the proposed power flow configuration are simulated using Matlab/ SimPowerSystems Toolbox and analyzed under three phase to ground short-circuits faults occurring in the middle of transmission line