Name: circuit source symbols and controls
Uploaded: 2024-04-11T12:48:28.000Z
Duration: 1 min 18 s
Channel: JoVE

Les sources d’un circuit peuvent être indépendantes ou dépendantes.
Des sources indépendantes de tension ou de courant fournissent une tension et un courant non affectés par d’autres éléments du circuit.
Les symboles des sources de tension indépendantes ont des polarités, tandis que les sources de courant indépendantes utilisent des flèches pour indiquer la direction du courant.
Un court-circuit est une source de tension indépendante de la tension zéro, tandis qu’un circuit ouvert est une source de courant indépendante du courant zéro.
Les sources dépendantes sont des générateurs de tension ou de courant contrôlés par d’autres éléments du circuit. Ils sont représentés par une forme de losange.
Sur la base de leurs parties de contrôle et de leurs parties contrôlées, les sources dépendantes sont divisées en quatre catégories.
Considérons un circuit où la tension de la source dépendante est contrôlée par le courant traversant la résistance.
Si un court-circuit est ajouté en série avec la résistance, le courant de contrôle est équivalent au courant dans le court-circuit.
Le rapport tension/courant de commande de la source représente le gain de la source dépendante.
De même, la tension de contrôle peut être considérée comme une tension en circuit ouvert.
Ainsi, la tension ou le courant des sources dépendantes est proportionnel à la tension ou au courant de commande.

sources indépendantes et dépendantes

Dans les circuits électriques, les sources jouent un rôle crucial en fournissant l'énergie nécessaire au fonctionnement du circuit. Ces sources peuvent être globalement classées en deux types : indépendantes et dépendantes. Des sources indépendantes de tension ou de courant fournissent respectivement une quantité fixe de tension ou de courant, qui n'est pas affectée par les autres éléments du circuit. Ceux-ci sont représentés à l'aide de symboles spécifiques. Les sources de tension indépendantes sont symbolisées par des polarités (+ et -) et indiquent la direction de la différence de potentiel, tandis que les sources de courant indépendantes utilisent des flèches pour indiquer la direction du flux de courant. Un aspect intéressant des sources indépendantes est qu'un court-circuit peut être considéré comme une source de tension indépendante de tension nulle car il permet au courant de circuler librement sans chute de tension. À l'inverse, un circuit ouvert peut être considéré comme une source de courant indépendante à courant nul, étant donné qu'il empêche toute circulation de courant quelle que soit la tension appliquée. D'autre part, les sources dépendantes sont des générateurs de tension ou de courant dont les valeurs sont contrôlées par d'autres éléments au sein du même circuit. Ils sont représentés par une forme de losange dans les schémas de circuits. Ces sources dépendantes sont divisées en quatre catégories en fonction de leurs parties contrôlantes et contrôlées : sources de tension contrôlées en tension (VCVS), sources de tension contrôlées en courant (CCVS), sources de courant contrôlées en tension (VCCS) et sources de courant contrôlées en courant (CCCS). Par exemple, dans un circuit où la tension de sortie d'une source dépendante est contrôlée par le courant circulant à travers une résistance, si un court-circuit est ajouté en série avec cette résistance, le courant de contrôle devient équivalent au courant dans le court-circuit. Le rapport entre la tension de la source et le courant de contrôle représente le gain de la source dépendante. De même, la tension de commande peut être considérée comme une tension en circuit ouvert. Cela signifie que la tension ou le courant des sources dépendantes est proportionnel à la tension ou au courant de contrôle.

Sources indépendantes et dépendantes

Les sources d’un circuit peuvent être indépendantes ou dépendantes.
Sources indépendantes de tension ou de courant : tension et courant d’alimentation non affectés par d’autres circuits, ...

Education

Enseignement

JoVE Core

Electrical Engineering

Génie électrique

Unit 1

Unité 1

Basics of Electric Circuits

Les bases des circuits électriques

KEY TERMS AND CONCEPTS

TERMES ET CONCEPTS CLÉS

Independent and Dependent Sources

circuit source symbols and controls

Circuit sources in electrical circuits can be independent or dependent. They provide the power a circuit needs to operate. Independent voltage sources supply a fixed voltage, and independent current sources supply a fixed current. Their output does not change because of other parts in the circuit.

These sources use standard symbols in circuit diagrams. An independent voltage source is shown with + and - signs to mark the potential difference. An independent current source is shown with an arrow to show the direction of current flow. A short circuit can be treated as a zero-voltage independent voltage source because it allows current to flow with no voltage drop. An open circuit can be treated as a zero-current independent current source because it blocks current flow even when voltage is applied.

Dependent sources work differently. Their voltage or current is controlled by another element in the same circuit. They are drawn with a diamond shape. There are four types: voltage-controlled voltage sources, current-controlled voltage sources, voltage-controlled current sources, and current-controlled current sources.

The controlling part can be tied to a resistor or another circuit element. For example, if the output voltage of a dependent source is controlled by the current through a resistor, adding a short circuit in series with that resistor makes the controlling current the same as the current in the short circuit. The ratio of the source voltage to the controlling current gives the gain of the dependent source. In a similar way, the controlling voltage can be treated as an open-circuit voltage. This means the voltage or current from a dependent source is proportional to the controlling voltage or current.

Circuit Source Symbols and Controls

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independent and dependent sources

Circuit sources in electrical circuits can be independent or dependent. They provide the power a circuit needs to operate. Independent voltage sources supply a fixed voltage, and independent current sources supply a fixed current. Their output does not change because of other parts in the circuit. These sources use standard symbols in circuit diagrams. An independent voltage source is shown with + and - signs to mark the potential difference. An independent current source is shown with an...

ohm's law

Resistance and Conductance in Circuits

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kirchhoff's current law

Kirchhoff's Current Law at Circuit Nodes

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Voltage Balance in Closed Circuit Loops

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Series Resistors and Voltage Split

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current dividers

Parallel Resistors and Current Division

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key terms and concepts

Learn how independent and dependent sources work in circuits, how they are drawn, and how control by voltage or current determines dependent source gain.

Circuit Source Symbols and Controls | 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

Circuit Source Symbols and Controls

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