Name: norton equivalent circuit in dc analysis
Uploaded: 2024-04-11T12:48:31.000Z
Duration: 1 min 14 s
Channel: JoVE

Le théorème de Norton stipule que tout circuit linéaire à deux bornes peut être remplacé par un circuit équivalent composé d'une seule source de courant en parallèle avec une résistance.
Pour mettre en œuvre le théorème de Norton, retirez la résistance de charge des deux bornes de charge : le réseau restant sera substitué par le circuit équivalent de Norton vu à partir de ces bornes.
La résistance de Norton peut être déterminée en mettant toutes les sources indépendantes à zéro. L'équivalent ou la résistance d'entrée entre les bornes est la résistance de Norton.
Pour trouver le courant de Norton, renvoyez toutes les sources à leur position d'origine. Ensuite, calculez le courant de Norton en trouvant le courant de court-circuit entre les bornes marquées.
Enfin, remplacez le réseau par le circuit équivalent Norton et reconnectez la résistance de charge.
La technique de transformation de source peut être utilisée pour convertir entre des circuits équivalents de Norton et de Thévenin.
La tension en circuit ouvert, le courant de court-circuit et la résistance d’entrée ou équivalente doivent être connus pour déterminer le circuit équivalent Thevenin ou Norton.
La relation étroite entre les théorèmes de Norton et de Thévenin et la loi d'Ohm permet de résoudre des circuits électriques complexes.

théorème de norton

Le théorème de Norton est un principe fondamental selon lequel un circuit linéaire à deux bornes peut être remplacé par un circuit équivalent, qui comprend une source de courant (ⅠN) en parallèle avec une résistance (RN). Ici, ⅠN représente le courant de court-circuit circulant à travers les bornes, et RN représente la résistance d'entrée ou équivalente aux bornes lorsque toutes les sources indépendantes sont désactivées. Cela implique que le circuit illustré sur la figure (a) peut être échangé avec celui représenté sur la figure (b). <img alt="Figure1" src="/files/ftp_upload/15054/15054_PT_Figure_1.svg" style="text-align: center; height: 132px;"> Figure (a) <img alt="Figure1" src="/files/ftp_upload/15054/15054_PT_Figure_2.svg" style="text-align: center; height: 132px;"> Figure (b) La détermination de la résistance de Norton implique le processus de mise à zéro de toutes les sources indépendantes du circuit. La valeur résultante représente la résistance de Norton, essentielle à l'application du théorème. Pour calculer le courant de Norton, il faut restaurer toutes les sources dans leurs configurations d'origine, puis vérifier le courant de court-circuit entre les bornes marquées. Le remplacement du réseau par le circuit équivalent Norton et la reconnexion de la résistance de charge sont nécessaires pour terminer la transformation. Pour établir le circuit équivalent Thévenin ou Norton, il faut connaître la tension en circuit ouvert, le courant de court-circuit et la résistance d'entrée ou équivalente. Ces paramètres servent d’entrées cruciales pour ces transformations de circuits. La relation étroite entre les théorèmes de Norton et de Thévenin donnée par les relations suivantes; <img alt="Equation1" src="/files/ftp_upload/15054/15054_PT_Equation_1.svg" style="text-align: center; height: 14px;"> <img alt="Equation1" src="/files/ftp_upload/15054/15054_PT_Equation_2.svg" style="text-align: center; height: 34px;"> couplé aux principes de la loi d'Ohm, fournit des outils précieux pour résoudre des circuits électriques complexes.

Théorème de Norton

Le théorème de Norton stipule que tout circuit linéaire à deux bornes peut être remplacé par un circuit équivalent composé d'une seule source de courant 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

Norton's Theorem

norton equivalent circuit in dc analysis

Norton equivalent circuit in DC analysis shows how a linear two-terminal circuit can be replaced by a simpler network. The replacement uses a current source, called I_N, in parallel with a resistor, called R_N. I_N is the short-circuit current through the terminals, and R_N is the input or equivalent resistance seen at the terminals when the independent sources are turned off.

To find Norton's resistance, all independent sources in the circuit are set to zero. The resistance measured at the marked terminals is then taken as R_N. To find Norton's current, the sources are restored to their original values and the short-circuit current between the terminals is found.

After the Norton equivalent is built, the load resistor is connected again to complete the transformation. This method gives a compact way to study how the circuit behaves at its terminals. It is closely linked to Thevenin's theorem, since both use the open-circuit voltage, short-circuit current, and equivalent resistance.

These relationships, together with Ohm's law, help solve more complex electrical circuits. By converting a network into its Norton form, students can compare terminal behavior more easily. The theorem is a useful tool for circuit analysis when a two-terminal linear network must be simplified.

Norton Equivalent Circuit in DC Analysis

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Norton equivalent circuit in DC analysis shows how a linear two-terminal circuit can be replaced by a simpler network. The replacement uses a current source, called I_N, in parallel with a resistor, called R_N. I_N is the short-circuit current through the terminals, and R_N is the input or equivalent resistance seen at the terminals when the independent sources are turned off. To find Norton's resistance, all independent sources in the circuit are set to zero. The resistance measured at the...

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Learn how Norton equivalent circuits simplify a linear two-terminal network using a current source, parallel resistance, and short-circuit current.

Norton Equivalent Circuit in DC 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

Norton Equivalent Circuit in DC Analysis

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