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

A análise de malha é um método conveniente que emprega correntes de malha como variáveis de circuito, reduzindo efetivamente o número de equações simultâneas envolvidas na análise de circuito.
Ao contrário da análise nodal, a análise de malha se aplica somente a circuitos planares sem ramificações cruzadas.
Determinar as correntes de malha em qualquer circuito planar envolve as seguintes etapas.
Primeiro, o número total de malhas independentes no circuito é identificado e as correntes de malha são atribuídas a cada malha.
Em segundo lugar, as tensões dos elementos são expressas como funções das correntes da malha, e a lei de tensão de Kirchhoff é aplicada a cada malha para obter um conjunto de equações lineares.
Finalmente, as correntes de malha são obtidas resolvendo o conjunto de equações.
Para um circuito com malhas independentes "i", a análise de malha requer equações independentes "i" para obter as correntes de malha.
Suponha que os valores das resistências e tensões da fonte para o circuito de duas malhas apresentado sejam conhecidos.
Esses valores são substituídos nas equações lineares e resolvidos para obter as correntes de malha.
Finalmente, os valores calculados das correntes de malha podem ser usados para determinar as correntes de ramificação i1, i2 e i3.

análise de malhas

A análise de malhas é um método valioso para simplificar a análise de circuitos usando correntes de malha como variáveis-chave do circuito. Ao contrário da análise nodal, que se concentra na determinação de tensões desconhecidas, a análise de malhas aplica a lei de tensões de Kirchhoff (LTK) para encontrar correntes desconhecidas dentro de um circuito. Esse método é particularmente conveniente para reduzir o número de equações simultâneas que precisam ser resolvidas.

Um conceito fundamental na análise de malhas é a definição de malhas e correntes de malha. Uma malha é um circuito fechado dentro de um circuito que não contém nenhum outro circuito dentro dele. Cada malha recebe uma corrente de malha, normalmente considerada como se estivesse fluindo no sentido horário dentro de seu respectivo loop.

Para que a análise de malhas seja aplicável, o circuito deve ser plano, o que significa que pode ser desenhado em uma superfície plana sem ramificações que se cruzem. Os circuitos planares são ideais para análise de malhas, pois simplificam o processo. As etapas envolvidas na análise da malhas são as seguintes:

<ul style="list-style-type: disc; margin-left: 35px;">
	<li>Atribua correntes de malha a cada uma das “n” malhas independentes do circuito.</li>
	<li>Aplique LTK a cada uma das malhas "n", expressando as tensões dos elementos em termos de correntes de malha usando a lei de Ohm.</li>
	<li>Resolva as equações "n" simultâneas resultantes para obter os valores das correntes de malha.</li>
</ul>

Essas correntes de malha podem então determinar várias correntes de ramificação dentro do circuito. É importante notar que as correntes de malha são distintas das correntes de ramificação, a menos que uma malha seja isolada.

Análise de malhas

A análise de malha é um método conveniente que emprega correntes de malha como variáveis de circuito, reduzindo efetivamente o número de equações simultâneas envolvidas ...

Education

JoVE Core

Electrical Engineering

Engenharia Elétrica

Unit 1

Unidade 1

DC Circuit Analysis

Análise de Circuitos CC

KEY TERMS AND CONCEPTS

TERMOS E CONCEITOS-CHAVE

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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mesh 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...

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...

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superposition theorem

Analyzing Circuits with Superposition

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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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design example: strain gauge bridge or wheatstone bridge

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key terms and concepts

Learn how mesh currents and Kirchhoff's voltage law simplify planar circuit analysis by turning loops into solvable current equations for high school students.

Mesh Currents for 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

Mesh Currents for Circuit Analysis

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