Name: rl step response under a dc source
Uploaded: 2024-04-11T12:48:43.000Z
Duration: 1 min 14 s
Channel: JoVE

Quando um circuito RL é conectado a uma fonte CC, sua resposta completa é dividida em respostas transitórias e de estado estacionário.
A resposta transitória é a resposta temporária do circuito que decai exponencialmente para zero à medida que o tempo se aproxima do infinito.
O indutor então atua como um curto-circuito e a tensão da fonte cai no resistor.
Nesse instante, a corrente no circuito torna-se estável e é igual à relação entre a tensão da fonte e a resistência. Esta é a resposta em estado estacionário.
Substituindo o estado estacionário e a resposta transitória, obtém-se a resposta total do circuito RL.
O termo constante é determinado substituindo a corrente inicial através do indutor em um tempo igual a zero.
A resposta completa do degrau, representada graficamente, mostra que a corrente inicial diminui exponencialmente para um valor de estado estacionário.
Se a corrente inicial for zero, a resposta completa do passo mostra o aumento exponencial da corrente para um valor de estado estacionário.
A resposta de tensão diminui exponencialmente para zero com uma tensão inicial igual à tensão da fonte.

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circuito rl com fonte

Quando um circuito RL (Resistor-Indutor) é conectado a uma fonte DC, a resposta completa do circuito pode ser dividida em duas partes: a resposta transitória e a resposta em estado estacionário.

A resposta transitória do circuito é a sua reação temporária à aplicação repentina da fonte DC. Esta resposta é caracterizada por uma corrente que decai exponencialmente até zero à medida que o tempo se aproxima do infinito. Durante este período de transição, o indutor se comporta como um curto-circuito, fazendo com que a tensão da fonte caia no resistor.

Uma vez que a resposta transitória decaiu para zero, o circuito entra em sua fase de estado estacionário. Nesta fase, a corrente no circuito torna-se estável, igualando a relação entre a tensão da fonte e a resistência do circuito. Esta é a resposta de estado estacionário.

O termo constante na resposta transitória pode ser determinado substituindo a corrente inicial através do indutor no momento em que a chave é fechada (t=0). Isso nos dá a condição inicial para a resposta transitória.

Traçar a resposta completa ao degrau do circuito mostra que a corrente inicial diminui exponencialmente até atingir um valor de estado estacionário. A partir desta resposta de corrente, deriva-se a resposta de tensão, que também segue um decaimento exponencial de um valor máximo a zero.

Se a corrente inicial no circuito for zero, a resposta ao degrau completa mostra a corrente aumentando exponencialmente até atingir o valor de estado estacionário. Correspondentemente, a resposta da tensão começa na tensão da fonte e diminui exponencialmente até zero.

Concluindo, compreender a resposta completa de um circuito RL a uma fonte DC fornece informações valiosas sobre como esses circuitos reagem a mudanças repentinas na tensão de entrada. Este conhecimento é essencial para projetar e analisar circuitos eletrônicos, particularmente em aplicações como filtragem de fontes de alimentação e processamento de sinais, onde os indutores são amplamente utilizados.

Circuito RL com Fonte

Quando um circuito RL é conectado a uma fonte CC, sua resposta completa é dividida em respostas transitórias e de estado estacionário.
A resposta transitória é a ...

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Electrical Engineering

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First and Second-Order Circuits

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KEY TERMS AND CONCEPTS

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RL Circuit with Source

rl step response under a dc source

An RL circuit connected to a DC source has a step response that changes over time. The response has two parts: the transient response and the steady-state response. The transient response is the short-lived reaction that happens right after the source is applied.

During the transient phase, the current changes exponentially. If the circuit starts with current in the inductor, that current decays toward zero as time goes on. At this stage, the inductor acts like a short circuit, so the source voltage drops across the resistor.

The constant term in the transient response comes from the initial inductor current at the moment the switch closes, which is t = 0. That initial value gives the starting condition for the response. As the transient dies out, the circuit reaches steady state.

In steady state, the current becomes stable. Its value equals the source voltage divided by the resistance. The current response can be plotted to show the exponential change toward this final value.

The voltage response is also derived from the current response. When the current decays from an initial value, the voltage drops exponentially from a maximum value to zero. If the initial current is zero, the current instead rises exponentially to the steady-state value, and the voltage starts at the source voltage and falls to zero.

Understanding the complete response of an RL circuit to a DC source helps explain how these circuits react to sudden changes in input voltage. This idea is useful in circuit design and analysis. It is especially important in applications such as power supply filtering and signal processing, where inductors are used extensively.

RL Step Response Under a DC Source

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Explore how an RL circuit responds to a DC source, including transient and steady-state behavior, exponential current change, and voltage decay.

RL Step Response Under a DC Source | 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

RL Step Response Under a DC Source

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