Name: mesh currents for circuit analysis
Uploaded: 2024-04-11T12:48:30.000Z
Duration: 1 min 20 s
Channel: JoVE

L’analyse de maillage est une méthode pratique qui utilise les courants de maillage comme variables de circuit, réduisant ainsi efficacement le nombre d’équations simultanées impliquées dans l’analyse de circuit.
Contrairement à l’analyse nodale, l’analyse de maillage ne s’applique qu’aux circuits planaires sans branches croisées.
La détermination des courants de maillage dans n’importe quel circuit planaire implique les étapes suivantes.
Tout d’abord, le nombre total de maillages indépendants dans le circuit est identifié et des courants de maillage sont attribués à chaque maillage.
Deuxièmement, les tensions des éléments sont exprimées en fonction des courants de maillage, et la loi de tension de Kirchhoff est appliquée à chaque maillage pour obtenir un ensemble d'équations linéaires.
Enfin, les courants de maillage sont obtenus en résolvant l’ensemble des équations.
Pour un circuit avec des maillages indépendants « i », l’analyse du maillage nécessite des équations indépendantes « i » pour obtenir les courants de maillage.
Supposons que les valeurs des résistances et des tensions de source pour le circuit à deux mailles présenté soient connues.
Ces valeurs sont substituées dans les équations linéaires et résolues pour obtenir les courants de maillage.
Enfin, les valeurs calculées des courants de maillage peuvent être utilisées pour déterminer les courants de dérivation i1, i2 et i3.

analyse de maillage

L'analyse de maillage est une méthode précieuse pour simplifier l'analyse de circuit en utilisant les courants de maillage comme variables clés du circuit. Contrairement à l'analyse nodale, qui se concentre sur la détermination de tensions inconnues, l'analyse de maillage applique la loi de tension de Kirchhoff (KVL) pour rechercher des courants inconnus dans un circuit. Cette méthode est particulièrement pratique pour réduire le nombre d’équations simultanées à résoudre.

Un concept fondamental dans l'analyse de maillage est la définition des maillages et des courants de maillage. Un maillage est une boucle fermée dans un circuit qui ne contient aucune autre boucle. Chaque maillage se voit attribuer un courant de maillage, généralement supposé circuler dans le sens des aiguilles d'une montre à l'intérieur de sa boucle respective.

Pour que l’analyse de maillage soit applicable, le circuit doit être plan, ce qui signifie qu’il peut être dessiné sur une surface plane sans que les branches ne se croisent. Les circuits planaires sont idéaux pour l’analyse de maillage, car ils simplifient le processus. Les étapes impliquées dans l'analyse du maillage sont les suivantes :

<ul style="padding-left: 35px; list-style: disc;">

	<li>Attribuez des courants de maille à chacune des « n » mailles indépendantes du circuit.</li>

	<li>Appliquez KVL à chacune des mailles « n », en exprimant les tensions des éléments en termes de courants de maille en utilisant la loi d'Ohm.</li>

	<li>Résolvez les « n » équations simultanées résultantes pour obtenir les valeurs des courants de maillage.</li>
</ul> 

Ces courants de maillage peuvent ensuite déterminer divers courants de dérivation au sein du circuit. Il est important de noter que les courants de maillage sont distincts des courants de branche, sauf si un maillage est isolé.

Analyse de maillage

L’analyse de maillage est une méthode pratique qui utilise les courants de maillage comme variables de circuit, réduisant ainsi efficacement le nombre d’équations simultanées impliquées ...

Education

Enseignement

JoVE Core

Electrical Engineering

Génie électrique

Unit 1

Unité 1

DC Circuit Analysis

Analyse des circuits CC

KEY TERMS AND CONCEPTS

TERMES ET CONCEPTS CLÉS

Mesh Analysis

mesh currents for circuit analysis

Mesh currents give students a simpler way to analyze planar circuits. In mesh analysis, the unknowns are currents, not voltages. The method uses Kirchhoff's voltage law, or KVL, to build the equations needed to solve the circuit.

A mesh is a closed loop in a circuit that does not contain any smaller loops inside it. Each independent mesh is assigned a mesh current, and this current is usually drawn in the clockwise direction. These mesh currents are used as the main circuit variables during analysis.

Mesh analysis works only for planar circuits. A planar circuit is one that can be drawn on a flat surface without any branches crossing. This shape makes the method easier to apply because the loops are clear and separate.

The process starts by assigning mesh currents to the n independent meshes in the circuit. Next, KVL is applied to each mesh, and element voltages are written in terms of mesh currents using Ohm's law. The resulting n simultaneous equations are then solved to find the mesh currents, which can be used to determine branch currents. Mesh currents and branch currents are not the same unless a mesh is isolated.

Mesh Currents for Circuit Analysis

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Mesh Currents for Circuit Analysis | JoVE K12

JoVE Core Electrical Engineering offers easy-to-understand animated videos that cover fundamental concepts of electric circuits along with circuit analysis techniques. It incorporates first-order and second-order circuits using operational amplifiers and circuit transformation concepts. The inclusion of practical design examples and real-world applications through scientist-in-action videos adds significant educational value, making complex concepts accessible.

electrical engineering

Mesh Currents for Circuit Analysis

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