Name: mesh currents for circuit analysis
Uploaded: 2024-04-11T12:48:30.000Z
Duration: 1 min 20 s
Channel: JoVE

L'analisi della mesh è un metodo conveniente che impiega le correnti di mesh come variabili del circuito, riducendo efficacemente il numero di equazioni simultanee coinvolte nell'analisi del circuito.
A differenza dell'analisi nodale, l'analisi mesh si applica solo ai circuiti planari senza diramazioni incrociate.
La determinazione delle correnti di maglia in qualsiasi circuito planare prevede i seguenti passaggi.
Innanzitutto, viene identificato il numero totale di mesh indipendenti nel circuito e le correnti di mesh vengono assegnate a ciascuna mesh.
In secondo luogo, le tensioni degli elementi sono espresse come funzioni delle correnti di maglia e la legge della tensione di Kirchhoff viene applicata a ciascuna maglia per ottenere un insieme di equazioni lineari.
Infine, le correnti di maglia si ottengono risolvendo l'insieme delle equazioni.
Per un circuito con mesh indipendenti "i", l'analisi mesh richiede equazioni indipendenti "i" per ottenere le correnti mesh.
Supponiamo che i valori delle resistenze e delle tensioni di sorgente per il circuito a due maglie presentato siano noti.
Questi valori vengono sostituiti nelle equazioni lineari e risolti per ottenere le correnti di maglia.
Infine, i valori calcolati delle correnti di maglia possono essere utilizzati per determinare le correnti di derivazione i1, i2 e i3.

analisi di maglia

L'analisi di maglia è un metodo prezioso per semplificare l'analisi del circuito, utilizzando le correnti di maglia come variabili chiave del circuito. A differenza dell'analisi nodale, che si concentra sulla determinazione delle tensioni sconosciute, l'analisi di maglia applica la legge della tensione di Kirchhoff (KVL) per determinare correnti sconosciute all'interno di un circuito. Questo metodo è particolarmente conveniente per ridurre il numero di equazioni simultanee che devono essere risolte.

Un concetto fondamentale nell’ analisi di maglia è la definizione di una maglia e delle correnti di maglia. Una maglia è un circuito chiuso all'interno di un circuito, che non contiene altri circuiti al suo interno. A ciascuna maglia viene assegnata una corrente di maglia, generalmente si presume che scorra in direzione oraria all'interno del rispettivo circuito.

Affinché l'analisi di maglia sia applicabile, il circuito deve essere planare, ovvero deve poter essere disegnato su una superficie piana senza che i rami si incrocino. I circuiti planari sono ideali per questo tipo di analisi, poiché semplificano il processo. I passaggi coinvolti nell'analisi di maglia sono i seguenti:

<ul style="list-style-type: disc; display: flex; flex-direction: column; gap: 10px; padding: 0 0 0 40px;">
	<li>Assegnare le correnti di maglia a ciascuna delle maglie "n" indipendenti nel circuito.</li>
	<li>Applicare KVL a ciascuna delle maglie "n", esprimendo le tensioni degli elementi in termini di correnti di maglia, utilizzando la legge di Ohm.</li>
	<li>Risolvere le equazioni simultanee "n" risultanti per ottenere i valori delle correnti di maglia.</li>
</ul>

Queste correnti di maglia possono quindi determinare varie correnti di ramo all'interno del circuito. È importante notare che le correnti di maglia sono distinte dalle correnti di ramo a meno che una maglia non sia isolata.

Analisi di Maglia

L'analisi della mesh è un metodo conveniente che impiega le correnti di mesh come variabili del circuito, riducendo efficacemente il numero di equazioni simultanee coinvolte ...

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

mesh currents for circuit analysis

Mesh currents give students a simpler way to analyze planar circuits. In mesh analysis, the unknowns are currents, not voltages. The method uses Kirchhoff's voltage law, or KVL, to build the equations needed to solve the circuit.

A mesh is a closed loop in a circuit that does not contain any smaller loops inside it. Each independent mesh is assigned a mesh current, and this current is usually drawn in the clockwise direction. These mesh currents are used as the main circuit variables during analysis.

Mesh analysis works only for planar circuits. A planar circuit is one that can be drawn on a flat surface without any branches crossing. This shape makes the method easier to apply because the loops are clear and separate.

The process starts by assigning mesh currents to the n independent meshes in the circuit. Next, KVL is applied to each mesh, and element voltages are written in terms of mesh currents using Ohm's law. The resulting n simultaneous equations are then solved to find the mesh currents, which can be used to determine branch currents. Mesh currents and branch currents are not the same unless a mesh is isolated.

Mesh Currents for Circuit Analysis

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electrical engineering

Mesh Currents for Circuit Analysis

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