Name: circuit source equivalents
Uploaded: 2025-05-22T09:06:14.000Z
Duration: 1 min 15 s
Channel: JoVE

La técnica de transformación de la fuente permite la conversión de una fuente de voltaje en serie con una resistencia en una fuente de corriente equivalente en paralelo con la resistencia o viceversa.
Durante la transformación, los valores de la resistencia en el circuito permanecen iguales. Usando la ley de Ohm, se pueden determinar los valores de voltaje o corriente.
La flecha de la fuente de corriente siempre apunta hacia el terminal positivo de la fuente de voltaje.
Esta técnica no se puede aplicar a fuentes ideales de voltaje y corriente debido a sus características de resistencia interna.
Considere un circuito que consta de una fuente de voltaje, una fuente de corriente y algunas resistencias. Usando la transformación de la fuente, se puede determinar la caída de voltaje a través de la resistencia central.
Inicialmente, aplique la transformación de la fuente en ambas fuentes para obtener el circuito reducido.
Ahora transforme la fuente de voltaje izquierda nuevamente en una fuente de corriente. El circuito se simplifica aún más en una configuración de fuente de corriente única.
Usando la fórmula de división de corriente, se obtiene la corriente a través de la resistencia. Al sustituirlo en la ley de Ohm, se obtiene la caída de voltaje a través de la resistencia.

transformación de fuente

La transformación de fuente es una técnica fundamental empleada en el análisis de circuitos y ofrece una herramienta valiosa para simplificar circuitos eléctricos complejos. Esta técnica implica el reemplazo de una fuente de voltaje en serie con una resistencia por una fuente de corriente en paralelo con una resistencia, o viceversa. El concepto clave aquí es que cuando las fuentes originales se desactivan (apagan), la resistencia equivalente en los terminales finales del circuito sigue siendo la misma. Es esencial tener en cuenta que al realizar transformaciones de fuente, la dirección de la flecha de la fuente de corriente siempre apunta hacia el terminal positivo de la fuente de voltaje. Esta convención garantiza la coherencia y ayuda a mantener la orientación adecuada del circuito. Sin embargo, cabe mencionar que la transformación de fuente no es aplicable a fuentes de voltaje ideales, ya que poseen resistencia interna cero. Por el contrario, las fuentes de voltaje no ideales presentan una resistencia interna distinta de cero, lo que las hace susceptibles de transformación de fuente. De manera similar, las fuentes de corriente ideales con resistencia interna infinita no pueden sustituirse por fuentes de voltaje finito. Para ilustrar la aplicación práctica de la transformación de fuente, considere un circuito conectado a una fuente de voltaje no ideal (Figura 1) y una fuente de corriente no ideal (Figura 2) individualmente. Cuando la resistencia en serie es igual a la resistencia en paralelo y el voltaje a través de la fuente de voltaje se adhiere a la ley de Ohm, estas fuentes no ideales se vuelven equivalentes entre sí. <img alt="Figure1" src="/files/ftp_upload/15051/15051_PT_Figure_1.svg" style="text-align: center; height: 128px;"> Figura 1: Circuito con una fuente de voltaje no ideal <img alt="Figure2" src="/files/ftp_upload/15051/15051_PT_Figure_2.svg" style="text-align: center; height: 128px;"> Figura 2: Circuito con una fuente de corriente no ideal Reemplazar la fuente de voltaje no ideal con la fuente de corriente no ideal equivalente no altera las características de voltaje o corriente de ningún elemento dentro del circuito. Esto demuestra el poder de la transformación de fuentes para simplificar el análisis de circuitos sin afectar el comportamiento general del circuito.

Transformación de fuente

La técnica de transformación de la fuente permite la conversión de una fuente de tensión en serie con una resistencia en una fuente de corriente equivalente en paralelo ...

Education

Educación

JoVE Core

Electrical Engineering

Ingeniería Eléctrica

Unit 1

Unidad 1

DC Circuit Analysis

Análisis de circuitos de CC

KEY TERMS AND CONCEPTS

TÉRMINOS Y CONCEPTOS CLAVE

Source Transformation

circuit source equivalents

Circuit source equivalents make it easier to simplify electrical circuits in circuit analysis. A source transformation replaces a voltage source in series with a resistor by a current source in parallel with a resistor, or it replaces a current source in parallel with a resistor by a voltage source in series with a resistor.

The key idea is that the equivalent resistance at the circuit terminals stays the same when the original sources are turned off. When making the change, the current source arrow must point toward the positive terminal of the voltage source. This keeps the circuit orientation consistent.

Source transformation does not work for ideal voltage sources because they have zero internal resistance. It also does not work for ideal current sources because they have infinite internal resistance. Nonideal voltage sources and nonideal current sources can be transformed because their internal resistance is not zero or infinite.

The transcript shows this idea with a nonideal voltage source and a nonideal current source. When the series resistance matches the parallel resistance, and the voltage across the voltage source follows Ohm's law, the two sources are equivalent. Replacing the nonideal voltage source with the matching nonideal current source does not change the voltage or current in any circuit element.

Circuit Source Equivalents

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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

Circuit Source Equivalents

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