Name: norton current in ac circuit analysis
Uploaded: 2024-04-11T12:48:50.000Z
Duration: 1 min 16 s
Channel: JoVE

Il teorema di Norton afferma che qualsiasi rete lineare a due terminali può essere sostituita da un circuito equivalente costituito da una sorgente di corrente costante in parallelo con un'impedenza.
Per determinare il valore dell'impedenza parallela, la sorgente viene sostituita con la sua impedenza interna. L'impedenza equivalente di questo circuito risultante è l'impedenza di Norton, che è la stessa dell'impedenza di Thévenin.
Per determinare la corrente di Norton, posizionare nuovamente le sorgenti nel circuito e analizzare la tensione a circuito aperto, che è la tensione di Thévenin.
La tensione di Thévenin è determinata dal prodotto della corrente di sorgente e dell'impedenza di Thevenin.
La stessa tensione viene fatta cadere attraverso l'impedenza di carico quando è collocata in una configurazione parallela.
Ricordiamo la relazione tra la corrente di Norton, la tensione di Thévenin e l'impedenza di Thévenin. Sostituendo i valori, consente di determinare la corrente di Norton.
Il teorema di Norton è utile per l'analisi e la progettazione di sistemi contenenti circuiti CA complessi.
Determinando il circuito equivalente di Norton per ogni stadio o sezione del circuito complesso, l'analisi del sistema complessivo può essere semplificata.

circuiti equivalenti di norton

Il teorema di Norton è un concetto fondamentale nel campo dell'ingegneria elettrica che consente la semplificazione di circuiti CA complessi. Il teorema afferma che qualsiasi rete lineare a due terminali, può essere sostituita con un circuito equivalente costituito da un'impedenza, parallela a una sorgente di corrente costante. La Figura 1 mostra il circuito CA suddiviso in due parti: Circuito A e Circuito B, mentre la Figura 2 mostra il circuito ottenuto sostituendo il Circuito A con il suo circuito equivalente Norton.

<img alt="Figure1" src="/files/ftp_upload/15114/15114_PT_Figure_1.svg" style="text-align: center; height: 160px;">
Figura 1: Un circuito suddiviso in due parti 

<img alt="Figure2" src="/files/ftp_upload/15114/15114_PT_Figure_2.svg" style="text-align: center; height: 160px;">
Figura 2: Circuito equivalente Norton

Per calcolare il valore dell'impedenza parallela, è necessario sostituire la sorgente con la sua impedenza interna, ottenendo un circuito con un'impedenza equivalente, nota come impedenza di Norton. L'impedenza di Norton è uguale all'impedenza di Thévenin e viene utilizzata per determinare la corrente di Norton, ovvero la corrente che scorre attraverso il circuito.

Per determinare la corrente di Norton è necessario reinserire le sorgenti nel circuito e analizzare la tensione a circuito aperto, anche nota quest’ultima, come tensione di Thévenin. Il valore della tensione di Thévenin, viene determinato moltiplicando la corrente sorgente per l'impedenza di Thevenin e viene utilizzato per far cadere la stessa tensione attraverso l'impedenza di carico, quando è posizionata in una configurazione parallela.

Utilizzando la relazione tra la corrente di Norton, la tensione di Thévenin e i valori della corrente di Norton, è possibile determinare la corrente di Norton del circuito. Questa relazione rende il teorema di Norton utile per l'analisi e la progettazione di sistemi contenenti circuiti CA complessi, poiché semplifica la loro analisi suddividendo il circuito in sezioni più piccole e gestibili.

Circuiti Equivalenti di Norton

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

Education

Didattica

JoVE Core

Electrical Engineering

Ingegneria elettrica

Unit 1

Unità 1

AC Circuit Analysis

Analisi dei circuiti in CA

KEY TERMS AND CONCEPTS

TERMINI E CONCETTI CHIAVE

Norton Equivalent Circuits

norton current in ac circuit analysis

Norton’s theorem helps simplify complex AC circuits by replacing a two-terminal linear network with a smaller equivalent circuit. That equivalent circuit uses an impedance in parallel with a constant current source. The method lets students break one complicated circuit into two parts and analyze them more easily.

To build the Norton equivalent, the source is replaced by its internal impedance. The result is the Norton impedance, which is the same as the Thévenin impedance. This parallel impedance is the key value used in the equivalent circuit.

Finding the Norton current takes one more step. The sources are placed back into the circuit, and the open-circuit voltage is analyzed. That voltage is also called the Thévenin voltage, and it can be found by multiplying the source current by the Thévenin impedance.

The Thévenin voltage helps show the same voltage drop across the load impedance when the load is arranged in parallel. Using the relationship between the Norton current, the Thévenin voltage, and the Norton impedance makes it possible to determine the circuit current. This makes Norton’s theorem useful for analyzing and designing systems with complex AC circuits because it turns a hard problem into smaller, more manageable parts.

Norton Current in AC Circuit Analysis

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Learn how Norton’s theorem simplifies complex AC circuits with a parallel current source and impedance, and how Norton current is determined from Thévenin values.

Norton Current in AC 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

Norton Current in AC Circuit Analysis

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