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

Il teorema di sovrapposizione è usato in circuiti con più sorgenti indipendenti.
Per applicare questo teorema, mantenere una sorgente indipendente alla volta sostituendo la sorgente di tensione inattiva con un cortocircuito e la sorgente di corrente inattiva con un circuito aperto, rispettivamente.
Il teorema afferma che la tensione attraverso un elemento in un circuito lineare è la somma algebrica dei contributi delle sorgenti indipendenti.
Si consideri un circuito con una sorgente di tensione e una di corrente, in cui è necessario determinare la caduta di tensione attraverso un resistore.
La caduta di tensione ha contributi da entrambe le fonti indipendenti.
Il contributo della sorgente di tensione si ottiene impostando la sorgente di corrente a zero.
Applicando la legge della tensione di Kirchhoff, viene determinata la corrente di loop. Utilizzando la legge di Ohm, viene calcolata la caduta di tensione.
Allo stesso modo, il contributo della sorgente di corrente si ottiene impostando la sorgente di tensione a zero.
Combinando i resistori, si ottiene la resistenza equivalente. Utilizzando la regola della divisione di corrente e la legge di Ohm, viene determinata la caduta di tensione.
Infine, sommando i contributi provenienti da fonti indipendenti, si ottiene la caduta di tensione totale attraverso il resistore.

teorema di sovrapposizione

Il principio di sovrapposizione è un concetto fondamentale secondo cui in un circuito lineare, la tensione (o la corrente) che attraversa un elemento può essere determinata sommando i contributi individuali di ciascuna sorgente indipendente che agisce in modo isolato. Quando si ha a che fare con circuiti lineari contenenti più sorgenti indipendenti, questo principio funge da prezioso strumento di analisi. Per applicare efficacemente il principio di sovrapposizione, è necessario concentrarsi su una singola sorgente indipendente alla volta, disattivando tutte le altre. Questo approccio produce l'output (tensione o corrente) risultante dalla sorgente attiva.

L'effetto cumulativo di tutte le sorgenti attive può quindi essere determinato sommando algebricamente i loro contributi individuali. Ciò semplifica il processo di analisi del circuito. In particolare, le sorgenti dipendenti rimangono inalterate poiché sono governate da variabili del circuito. Vale la pena notare che l'utilizzo del principio di sovrapposizione può portare ad un maggiore sforzo analitico. Ad esempio, quando si ha a che fare con un circuito dotato di tre sorgenti indipendenti, occorre analizzare tre circuiti separati e semplificati, ciascuno dei quali rappresenta il contributo di una singola sorgente. Nonostante questo potenziale inconveniente, il principio di sovrapposizione rimane una tecnica preziosa per semplificare circuiti complessi sostituendo le sorgenti di tensione con cortocircuiti e le sorgenti di corrente con circuiti aperti.

Teorema di Sovrapposizione

Il teorema di sovrapposizione è usato in circuiti con più sorgenti indipendenti.
Per applicare questo teorema, mantieni una fonte indipendente alla volta mentre ...

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

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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superposition theorem

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thevinin's theorem

Thevenin Circuit Equivalents

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norton's theorem

Norton Equivalent Circuit in DC Analysis

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key terms and concepts

Learn how superposition helps solve linear circuits by analyzing one independent source at a time, then adding the voltage or current contributions.

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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