Name: ac source conversion in circuit analysis
Uploaded: 2024-04-11T12:48:49.000Z
Duration: 1 min 11 s
Channel: JoVE

Considere um circuito composto por uma fonte de corrente e uma combinação de resistores, capacitores e indutores com valores de impedância conhecidos.
O objetivo é utilizar a técnica de transformação da fonte para determinar a queda de tensão no ramo mais à direita do circuito.
Usando a transformação da fonte, uma fonte de corrente em paralelo com uma impedância pode ser convertida em uma fonte de tensão em série com a mesma impedância ou vice-versa.
Aplicando a lei de Ohm, a tensão da fonte é calculada. Este valor pode então ser expresso em termos de fasor.
No circuito transformado, a impedância está em série com a fonte de tensão, juntamente com os outros dois elementos do ramo superior. A impedância em série equivalente é obtida.
Agora, a técnica de transformação da fonte é aplicada novamente para converter a fonte de tensão de volta em uma fonte de corrente.
Em seguida, obtém-se a impedância da nova combinação paralela, que é utilizada para transformar a fonte de corrente de volta em uma fonte de tensão.
Finalmente, a regra de divisão de tensão determina a queda de tensão no ramo mais à direita.

transformação de fonte para circuitos ac

O processo de transformação da fonte no domínio da frequência envolve a conversão de uma fonte de tensão, posicionada em série com uma impedância, em uma fonte de corrente paralela a uma impedância, ou vice-versa. É essencial manter os seguintes relacionamentos durante a transição de um tipo de origem para outro.

<img alt="Equation1" src="/files/ftp_upload/15112/15112_PT_Equation_1.svg" style="text-align: center; height: 16px;" />

<img alt="Equation2" src="/files/ftp_upload/15112/15112_PT_Equation_2.svg" style="text-align: center; height: 40px;" />

Para determinar a tensão desconhecida para um circuito composto por uma fonte de corrente e um conjunto de resistores, capacitores e indutores - cada um com sua impedância conhecida distinta, uma série de etapas são seguidas. Inicialmente, a fonte de tensão é convertida em fonte de corrente, e os valores da corrente da fonte (Ⅰs) e da impedância (Zs) são estabelecidos.

Posteriormente, transformar a fonte de corrente de volta em uma fonte de tensão resulta em um circuito diferente. A partir deste circuito derivado, a tensão da fonte (Vs) é calculada utilizando os valores previamente determinados. Finalmente, aplicando a regra de divisão de tensão, a tensão desconhecida na resistência pode ser identificada.

Transformação de Fonte para Circuitos AC

Considere um circuito composto por uma fonte de corrente e uma combinação de resistores, capacitores e indutores com valores de impedância conhecidos.
O objetivo é ...

Education

JoVE Core

Electrical Engineering

Engenharia Elétrica

Unit 1

Unidade 1

AC Circuit Analysis

Análise de Circuitos CA

KEY TERMS AND CONCEPTS

TERMOS E CONCEITOS-CHAVE

Source Transformation for AC Circuits

ac source conversion in circuit analysis

AC source conversion is a circuit analysis method used in the frequency domain. It changes a voltage source in series with an impedance into a current source in parallel with the same impedance, or it converts a current source back into a voltage source. The source values must keep the correct relationship during each change.

This method helps solve for an unknown voltage in a circuit that includes a current source and components such as resistors, capacitors, and inductors. Each of these parts has a known impedance. The circuit is handled in steps so the final voltage can be found more easily.

First, the voltage source is converted into a current source. The source current, Is, and the source impedance, Zs, are identified. Next, the current source is changed back into a voltage source, which gives a new circuit form. From that derived circuit, the source voltage, Vs, is calculated. The final unknown voltage across the resistor is then found with the voltage division rule.

AC Source Conversion in Circuit Analysis

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phasors

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Phasor Rules for AC Circuit Analysis

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AC Circuit Phasors: Resistor, Inductor, Capacitor

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AC Circuit Rules with Phasor Diagrams

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AC Circuit Response: Impedance and Admittance

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Series and Parallel Impedance Rules

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source transformation for ac circuits

AC source conversion is a circuit analysis method used in the frequency domain. It changes a voltage source in series with an impedance into a current source in parallel with the same impedance, or it converts a current source back into a voltage source. The source values must keep the correct relationship during each change. This method helps solve for an unknown voltage in a circuit that includes a current source and components such as resistors, capacitors, and inductors. Each of these...

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Norton Current in AC Circuit Analysis

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key terms and concepts

Learn how AC source conversion turns voltage sources into current sources and back again to find unknown voltage with impedance and voltage division.

AC Source Conversion in 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

AC Source Conversion in Circuit Analysis

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