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

Il teorema di Norton afferma che qualsiasi circuito lineare a due terminali può essere sostituito da un circuito equivalente costituito da una singola sorgente di corrente in parallelo con un resistore.
Per implementare il teorema di Norton, rimuovere la resistenza di carico dai due terminali di carico: la rete rimanente sarà sostituita dal circuito equivalente di Norton visto da questi terminali.
La resistenza di Norton può essere determinata impostando tutte le fonti indipendenti a zero. L'equivalente o la resistenza di ingresso tra i terminali è la resistenza di Norton.
Per trovare l'attuale di Norton, riporta tutte le fonti alle loro posizioni originali. Quindi, calcola la corrente di Norton trovando la corrente di cortocircuito tra i terminali contrassegnati.
Infine, sostituire la rete con il circuito equivalente Norton e ricollegare la resistenza di carico.
La tecnica di trasformazione del sorgente può essere utilizzata per convertire tra circuiti equivalenti Norton e Thévenin.
La tensione a circuito aperto, la corrente di cortocircuito e la resistenza di ingresso o equivalente devono essere note per determinare il circuito equivalente di Thevenin o Norton.
La stretta relazione tra i teoremi di Norton e Thévenin e la legge di Ohm aiuta a risolvere circuiti elettrici complessi.

il teorema di norton

Il teorema di Norton è un principio fondamentale che afferma che un circuito lineare a due terminali può essere sostituito con un circuito equivalente, che comprende una sorgente di corrente (ⅠN) in parallelo con un resistore (RN). Qui, ⅠN rappresenta la corrente di cortocircuito che scorre attraverso i terminali e RN sta per l'ingresso o la resistenza equivalente sui terminali quando tutte le fonti indipendenti sono disattivate. Ciò implica che il circuito illustrato in Figure (a) può essere scambiato con quello illustrato in 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 determinazione della resistenza di Norton prevede il processo di impostazione a zero di tutte le fonti indipendenti all'interno del circuito. Il valore risultante rappresenta la resistenza di Norton, essenziale per l'applicazione del teorema. Per calcolare la corrente di Norton è necessario ripristinare tutte le sorgenti nelle loro configurazioni originali e quindi accertare la corrente di cortocircuito tra i terminali contrassegnati. Per completare la trasformazione è necessario sostituire la rete con il circuito equivalente Norton e ricollegare la resistenza di carico. Per realizzare il circuito equivalente di Thévenin o Norton, è necessario conoscere la tensione a circuito aperto, la corrente di cortocircuito e la resistenza di ingresso o equivalente. Questi parametri servono come input cruciali per queste trasformazioni del circuito. La stretta relazione tra i teoremi di Norton e di Thévenin data dalle seguenti relazioni,

<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;">

abbinato ai principi della legge di Ohm, fornisce strumenti preziosi per risolvere circuiti elettrici complessi.

Il teorema di Norton

Il teorema di Norton afferma che qualsiasi circuito lineare a due terminali può essere sostituito da un circuito equivalente costituito da una singola sorgente di corrente in ...

Education

Didattica

JoVE Core

Electrical Engineering

Ingegneria elettrica

Unit 1

Unità 1

DC Circuit Analysis

Analisi dei circuiti in CC

KEY TERMS AND CONCEPTS

TERMINI E CONCETTI CHIAVE

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.

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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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