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

O teorema da superposição é usado em circuitos com múltiplas fontes independentes.
Para aplicar este teorema, mantenha uma fonte independente de cada vez enquanto substitui a fonte de tensão inativa por um curto-circuito e a fonte de corrente inativa por um circuito aberto, respectivamente.
O teorema afirma que a tensão através ou a corrente através de um elemento em um circuito linear é a soma algébrica das contribuições das fontes independentes.
Considere um circuito com uma fonte de tensão e corrente, onde a queda de tensão em um resistor deve ser determinada.
A queda de tensão tem contribuições de ambas as fontes independentes.
A contribuição da fonte de tensão é obtida definindo a fonte de corrente como zero.
Aplicando a lei de tensão de Kirchhoff, a corrente do loop é determinada. Usando a lei de Ohm, a queda de tensão é calculada.
Da mesma forma, a contribuição da fonte de corrente é obtida definindo a fonte de tensão como zero.
Combinando os resistores, a resistência equivalente é obtida. Usando a regra da divisão de corrente e a lei de Ohm, a queda de tensão é determinada.
Finalmente, adicionando as contribuições de fontes independentes, a queda total de tensão no resistor é obtida.

teorema da superposição

O princípio da superposição é um conceito fundamental que afirma que em um circuito linear, a tensão (ou corrente através) de um elemento pode ser determinada pela soma das contribuições individuais de cada fonte independente agindo isoladamente. Ao lidar com circuitos lineares contendo múltiplas fontes independentes, esse princípio serve como uma ferramenta valiosa para análise. Para aplicar o princípio da superposição de forma eficaz, deve-se focar em uma única fonte independente de cada vez, enquanto desativa todas as outras. Essa abordagem produz a saída (tensão ou corrente) resultante da fonte ativa.

O efeito cumulativo de todas as fontes ativas pode então ser determinado adicionando por álgebra as suas contribuições individuais. Isso simplifica o processo de análise do circuito. Notavelmente, as fontes dependentes permanecem inalteradas, pois são governadas por variáveis ​​de circuito. É importante notar que a utilização do princípio da superposição pode levar a um maior esforço analítico. Por exemplo, ao lidar com um circuito com três fontes independentes, deve-se analisar três circuitos simplificados e separados, cada um representando a contribuição de uma fonte individual. Apesar dessa potencial desvantagem, o princípio da superposição continua sendo uma técnica valiosa para simplificar circuitos complexos, substituindo fontes de tensão por curtos-circuitos e fontes de corrente por circuitos abertos.

Teorema da superposição

O teorema da superposição é usado em circuitos com múltiplas fontes independentes.
Para aplicar este teorema, mantenha uma fonte independente de cada vez enquanto ...

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

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

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...

thevinin's theorem

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norton's theorem

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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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