Name: current sources in mesh circuit analysis
Uploaded: 2024-04-11T12:48:30.000Z
Duration: 1 min 10 s
Channel: JoVE

L'analisi della mesh è più semplice nei circuiti con sorgenti di corrente perché richiedono meno equazioni per l'analisi.
Si consideri un circuito a due mesh con una sorgente di corrente in una sola mesh.
Le correnti di mesh vengono assegnate e il ramo contenente l'origine di corrente viene escluso dall'analisi della mesh.
La legge della tensione di Kirchhoff viene applicata alla mesh rimanente per ottenere un'equazione lineare.
Poiché la corrente nella seconda mesh è uguale in grandezza ma opposta in direzione alla corrente sorgente, l'equazione semplificata consente di determinare la corrente nella prima mesh.
Ora, considera un altro circuito con una sorgente di corrente tra entrambe le mesh.
Una supermesh più grande viene creata escludendo la sorgente di corrente e gli elementi collegati in serie con essa.
Ancora una volta, applicando la legge della tensione di Kirchhoff alla supermesh si ottiene un'equazione lineare.
Inoltre, la legge corrente di Kirchhoff viene applicata a un nodo in cui il ramo con la sorgente di corrente è connesso, producendo un'altra equazione lineare che collega le due correnti di ramo.
Le soluzioni delle equazioni simultanee forniscono i valori delle correnti di maglia.

analisi delle maglie con sorgenti di corrente

L'analisi delle maglie diventa più semplice quando si analizzano circuiti con sorgenti di corrente, siano esse indipendenti o dipendenti. La presenza di una fonte di corrente riduce il numero di equazioni necessarie per l'analisi. Si distinguono due casi principali:

Sorgente di Corrente in una Singola Maglia: quando la sorgente di corrente è presente in una sola maglia all'interno del circuito, il processo di analisi è semplice. Si applica poi la Legge di Kirchhoff delle Tensioni (KVL) alla maglia rimanente, ottenendo un'equazione lineare. La corrente nella maglia contenente la fonte di corrente è nota in modulo e direzione, permettendo così una facile determinazione della corrente nella prima maglia.

Sorgente di Corrente tra due Maglie: nei casi in cui una sorgente di corrente sia situate tra due maglie adiacenti, l'analisi può essere semplificata introducendo una supermaglia. La supermaglia la si ottiene escludendo la fonte di corrente e qualsiasi elemento ad essa collegato in serie. Si applica la KVL alla supermaglia ottenendo un'equazione lineare. Inoltre, si utilizza la Legge di Kirchhoff delle Correnti (KCL) su un nodo collegato al ramo contenente la fonte di corrente, fornendo un'ulteriore equazione lineare che lega le correnti delle maglie. Risolvendo questo sistema di equazioni, si determinano i valori delle correnti di maglia.

Le proprietà fondamentali di una supermaglia includono:

<ul style="list-style-type: disc; display: flex; flex-direction: column; gap: 10px; padding: 0 0 0 40px;">
	<li>La fonte di corrente all'interno della supermaglia introduce un'equazione vincolante necessaria per determinare le correnti di maglia.</li>
	<li>​​Una supermaglia non ha una propria corrente, ma racchiude le correnti delle singole maglie che comprende.</li>
	<li>Si applicano la KVL e la KCL a una supermaglia nello stesso modo in cui si applicano a una maglia ordinaria.</li>
</ul>

Analisi delle Maglie con Sorgenti di Corrente

L'analisi della mesh è più semplice nei circuiti con sorgenti di corrente perché richiedono meno equazioni per l'analisi.
Considera un circuito a due maglie con una corrente ...

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

Mesh Analysis with Current Sources

current sources in mesh circuit analysis

Current sources make mesh circuit analysis easier because they can reduce the number of equations needed. This applies to both independent and dependent current sources. The method depends on where the current source is placed in the circuit.

When a current source appears in only one mesh, the setup is simple. Assign mesh currents as usual, but leave out the mesh that contains the current source from the equation process. Then apply Kirchhoff's voltage law, or KVL, to the remaining mesh to get a linear equation. The current in the mesh with the source is equal in magnitude but opposite in direction, so the first mesh current is easy to find.

A different case happens when a current source lies between two meshes. Here, the circuit can be handled with a supermesh, which is formed by excluding the current source and any elements in series with it. KVL is applied around the supermesh to create a linear equation. Then Kirchhoff's current law, or KCL, is used at a node connected to the current-source branch to link the two branch currents.

The current source inside a supermesh adds a needed constraint equation for solving the mesh currents. A supermesh has no current of its own. It combines the currents from the meshes it encloses. KVL and KCL are still applied to the supermesh like they are in any other mesh.

Current Sources in Mesh Circuit Analysis

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Learn how current sources simplify mesh circuit analysis, including one-mesh cases and supermeshes, using KVL and KCL to solve for mesh currents.

Current Sources in Mesh 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

Current Sources in Mesh Circuit Analysis

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