Name: analyzing circuits with superposition
Uploaded: 2024-04-11T12:48:31.000Z
Duration: 1 min 18 s
Channel: JoVE

Le théorème de superposition est utilisé dans les circuits avec plusieurs sources indépendantes.
Pour appliquer ce théorème, il faut conserver une source indépendante à la fois tout en remplaçant la source de tension inactive par un court-circuit et la source de courant inactive par un circuit ouvert, respectivement.
Le théorème stipule que la tension ou le courant traversant un élément dans un circuit linéaire est la somme algébrique des contributions des sources indépendantes.
Considérons un circuit avec une tension et une source de courant, où la chute de tension aux bornes d’une résistance doit être déterminée.
La chute de tension a des contributions des deux sources indépendantes.
La contribution de la source de tension est obtenue en mettant la source de courant à zéro.
En appliquant la loi de tension de Kirchhoff, le courant de boucle est déterminé. À l'aide de la loi d'Ohm, la chute de tension est calculée.
De même, la contribution de la source de courant est obtenue en mettant la source de tension à zéro.
En combinant les résistances, on obtient une résistance équivalente. À l'aide de la règle de division du courant et de la loi d'Ohm, la chute de tension est déterminée.
Enfin, en additionnant les contributions de sources indépendantes, on obtient la chute de tension totale aux bornes de la résistance.

théorème de superposition

Le principe de superposition est un concept fondamental selon lequel dans un circuit linéaire, la tension aux bornes (ou le courant traversant) un élément peut être déterminée en additionnant les contributions individuelles de chaque source indépendante qui agissent de manière isolée. Lorsqu'il s'agit de circuits linéaires contenant plusieurs sources indépendantes, ce principe constitue un outil d'analyse précieux. Pour appliquer efficacement le principe de superposition, il faut se concentrer sur une seule source indépendante à la fois tout en désactivant toutes les autres. Cette approche donne la sortie (tension ou courant) résultant de la source active. L'effet cumulatif de toutes les sources actives peut alors être déterminé en additionnant algébriquement leurs contributions individuelles. Cela simplifie le processus d'analyse des circuits. Notamment, les sources dépendantes ne sont pas affectées car elles sont régies par les variables du circuit. Il convient de noter que l'utilisation du principe de superposition peut conduire à un effort analytique accru. Par exemple, lorsqu'il s'agit d'un circuit comportant trois sources indépendantes, il faut analyser trois circuits distincts et simplifiés, chacun représentant la contribution d'une source individuelle. Malgré cet inconvénient potentiel, le principe de superposition reste une technique intéressante pour simplifier des circuits complexes en remplaçant les sources de tension par des courts-circuits et les sources de courant par des circuits ouverts.

Théorème de superposition

Le théorème de superposition est utilisé dans les circuits avec plusieurs sources indépendantes.
Pour appliquer ce théorème, conservez une source indépendante à la fois tout en ...

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

Superposition Theorem

analyzing circuits with superposition

Superposition is a circuit analysis method for linear circuits with more than one independent source. It lets you find the voltage across or current through an element by adding the separate effects of each source acting alone.

To use superposition, keep one independent source active and turn off the others. A voltage source is replaced by a short circuit, and a current source is replaced by an open circuit. Then calculate the output from the single active source.

Repeat the process for each independent source in the circuit. The final voltage or current is found by algebraically adding the individual results. Dependent sources are not turned off because they depend on circuit variables.

This method can simplify complex circuits, but it may take more work. A circuit with three independent sources must be analyzed as three separate simplified circuits. Even so, superposition remains a useful tool for breaking down difficult linear circuit problems.

Analyzing Circuits with Superposition

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Analyzing Circuits with Superposition | 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

Analyzing Circuits with Superposition

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