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Power Electronics : Third Year Bachelor's Degree in Electrotechnics
No full textThis document serves as a course material for power electronics primarily intended for third-year
Bachelor's students specializing in Electrotechnics within the Department of Electrical Systems
Engineering. It serves as a guiding resource for understanding the fundamentals and essential concepts of
power electronics. The document assumes that the students are already familiar with general circuit
analysis techniques usually taught at the S3 semester. While a basic understanding of electronic devices
like diodes and transistors is expected, the primary focus of this document lies in circuit topology and
functionality rather than individual devices. ..
Electronique de puissance avancée : première année master machines electriques
No full textLes développements récents des composants électronique de puissance et des techniques de
commande ont conduit à l’émergence de nouvelles topologies de convertisseurs de puissance, telles que
les redresseurs MLI, les onduleurs MLI et les convertisseurs multi-niveaux.
Le présent support de cours est destiné aux étudiants de la première année Master de la spécialité
Electrotechnique est un guide d’apprentissage des bases et les notions fondamentales de l’électronique de
puissance, centrées sur la nécessité de travailler en commutation pour pouvoir atteindre de forts
rendements et sur le fait que certaines modalités dans le transfert d’énergie électrique de la source vers le
récepteur sont alors à respecter...
Iterative method based optimization of wireless power transfer for biomedical implants
No full textMagnetic resonance coupling wireless power transfer (WPT) systems have gained increasing interest as an effective method for powering implantable medical devices (IMDs). Power transfer efficiency is a very important characteristic of WPT systems. It is characterized by the coupling and quality factors of the WPT coils. The maximum power transfer efficiency is obtained for high coupling and quality factors. It greatly depends on the geometrical parameters of the WPT coils. This paper presents an iterative procedure to design and optimize an implant coil restricted to a small size of 20mm at a distance of 30 mm, with an operating frequency of 13.56 MHz within the ISM frequency band. The proposed method aims to find the optimal geometrical parameters that maximize the power transfer efficiency. The designed coils give a high efficiency of about 83%. Finally, the finite element simulation with Ansys Maxwell 3D validates the obtained result
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Robust decoupled adaptive fuzzy sliding mode control for a class of underactuated mechanical systems
No full textNowadays, Underactuated Mechanical Systems (UMS) remain an interesting research field for control laws development. This work deals with the design of an adaptive controller on the basis of Sliding Mode Control (SMC) and the universal approximation property of Fuzzy Systems (FS) for a classe of second order UMS two Degrees of Freedom (DOF). We first design an SMC law to force a coupled sliding urface to be reached in finite time. Second, by considering model uncertainties, fuzzy systems are then introduced to approximate the unknown controller. The adjustable parameters are updated by using gradient descent method. Through the stability analysis for both cases, it is shown that the system converges asymptotically to its equilbrium points in finite time. To demonstrate the validity and the performance of the proposed methods, an appropriate numerical application to an overhead crane systems is presente
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Optimal design of wireless power transfer coils for biomedical implants using machine learning and meta-heuristic algorithms
No full textThe classical methods for optimizing wireless power transfer (WPT) systems using mathematical equations or finite element methods can be time-consuming and may only sometimes yield optimal designs. In order to overcome this challenge, this paper introduces a novel approach integrating machine learning techniques with meta-heuristic methods to design and optimize a miniaturized, high-efficiency WPT receiving coil for biomedical applications. The objective is to achieve dimensions below 20 mm, a depth of 30 mm within the tissue, and a frequency of 13.56 MHz. Our approach leverages a neural network (NN) model to predict efficiency based on geometric coil parameters, eliminating the need for complex equations. The NN was trained on a dataset generated via finite element method simulations. We employ two meta-heuristic algorithms, the genetic algorithm and the coyote optimization method, to find optimal parameters that maximize efficiency. Our NN model demonstrates exceptional accuracy, exceeding 97%. Furthermore, the proposed WPT coil design approach enhances transfer efficiency by up to 76%, significantly reducing computation time compared to classical methods. Finally, we validate our results using finite element simulation with Ansys Maxwell 3D
Contribution to improving the efficiency of a wireless power transfer system using artificial intelligence techniques
No full text104 p. : ill. ; 30 cmWireless Power Transfer (WPT) technology is an innovative method for powering devices without physical wires, which has been used here to provide power to bioimplantable devices. The main design constraints are to achieve maximum transfer efficiency while keeping the implant size small enough to be suitable for the living subject's body. Magnetic Resonant Coupling Wireless Power Transfer (MRCWPT), which uses pairs of inductor coils in the external and implant circuits, is a method actively researched for this type of power transmission.
The objective of this thesis is to design and optimize a high-efficiency WPT receiving coil for biomedical applications. Traditionally, optimizing WPT systems based on mathematical equations or numerical models is often time-consuming and may not yield optimal designs. To address these limitations, this thesis introduces a novel approach that integrates a machine-learning model with metaheuristic methods for design and optimization.
The primary goal is to maximize the transfer efficiency for an implantable coil with dimensions of 20 mm and a transfer distance of 30 mm, operating at a frequency of 13.56 MHz. To achieve this goal, we firstly identified the critical geometric coil parameters that significantly influence the WPT system's efficiency. A model-based Artificial Neural Network (ANN) was then constructed and trained on a comprehensive dataset generated through Finite Element Method (FEM) simulations. This model predicts efficiency based on geometric coil parameters, eliminating the need for complex calculations. Subsequently, two metaheuristic algorithms: the Genetic Algorithm (GA) and the Coyote Optimization Algorithm (COA), were employed to find the optimal parameters that maximize efficiency.
The proposed ANN model demonstrates exceptional accuracy, exceeding 97%. Furthermore, this WPT coil design approach significantly enhances transfer efficiency by up to 76% while drastically reducing computation time compared to conventional method
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