Name: thevenin circuit equivalents
Uploaded: 2024-04-11T12:48:31.000Z
Duration: 1 min 15 s
Channel: JoVE

El teorema de Thevenin establece que cualquier circuito lineal de dos terminales puede ser reemplazado por un circuito equivalente con una sola fuente de voltaje en serie con una resistencia.
En ausencia de carga, el voltaje a través de los terminales abiertos será el voltaje Thévenin.
Para encontrar resistencia a Thévenin, todas las fuentes independientes están desactivadas. Luego, la resistencia que se ve a través de los terminales es la resistencia de Thévenin.
Si el circuito contiene fuentes dependientes, las fuentes independientes siguen apagadas, pero se aplica una fuente de prueba conocida en los terminales.
A partir de la tensión o corriente terminal resultante, se puede determinar la resistencia de Thévenin.
Finalmente, la carga se conecta al circuito equivalente. La corriente a través de la carga se calcula utilizando la fórmula del divisor de corriente. Usando la ley de Ohm, se determina el voltaje de Thévenin a través de la carga.
Una batería se puede representar como el circuito equivalente de Thévenin. El voltaje de Thévenin es el voltaje de circuito abierto de la batería y la resistencia es su resistencia interna.
Conociendo los parámetros de Thévenin, es fácil calcular la corriente para varias cargas sin tener que volver a examinar todo el circuito.

teorema de thevinin

El teorema de Thévenin desempeña un papel fundamental en el análisis de circuitos eléctricos y ofrece una solución a los desafíos que plantean las cargas variables dentro de un circuito. En aplicaciones prácticas, es común encontrar circuitos donde ciertos elementos permanecen fijos mientras otros fluctúan, lo que a menudo se denomina "carga". Un tomacorriente doméstico típico sirve como un excelente ejemplo de carga variable, ya que se puede conectar a una variedad de electrodomésticos, cada uno con sus propias características eléctricas únicas. Cada vez que se conecta o retira un electrodoméstico nuevo, todo el circuito requiere un nuevo análisis. El teorema de Thévenin proporciona una técnica que reemplaza la porción fija del circuito con un circuito equivalente, simplificando así el análisis y el diseño. 

 El teorema de Thévenin establece que un circuito lineal de dos terminales puede representarse mediante un circuito equivalente que consta de una fuente de voltaje en serie con una resistencia. Este circuito equivalente encapsula efectivamente el comportamiento del circuito original desde una perspectiva externa. Dos parámetros críticos definen este circuito equivalente de Thévenin: el voltaje equivalente de Thévenin (VTh), que corresponde al voltaje de circuito abierto en los terminales, y la resistencia equivalente de Thévenin (RTh), que representa la entrada o resistencia equivalente en los terminales cuando todos Las fuentes independientes están desactivadas. 

 Para ilustrar aún más el concepto, considere dos circuitos que se muestran en la Figura 1 y la Figura 2. Estos circuitos se consideran equivalentes cuando comparten la misma relación voltaje-corriente en sus terminales. Cuando los terminales se dejan en circuito abierto, lo que no produce flujo de corriente, el voltaje a través de los terminales abiertos será el voltaje de Thévenin. Cuando todas las fuentes independientes están apagadas. Entonces la resistencia que se ve a través de los terminales es la resistencia de Thévenin. 

 <img alt="Figure1" src="/files/ftp_upload/15053/15053_PT_Figure_1.svg" style="text-align: center; height: 128px;"> 
 Figure 1 <img alt="Equation1" src="/files/ftp_upload/15053/15053_PT_Equation_1.svg" style="text-align: center; height: 14px;"> 
 <img alt="Figure2" src="/files/ftp_upload/15053/15053_PT_Figure_2.svg" style="text-align: center; height: 128px;"> 
 Figure 2
 <img alt="Equation2" src="/files/ftp_upload/15053/15053_PT_Equation_2.svg" style="text-align: center; height: 14px;"> 
 Para aplicar prácticamente esta idea y determinar la resistencia de Thévenin, debemos considerar dos escenarios: 
 CASO 1: En situaciones donde la red no contiene fuentes dependientes, se desactivan todas las fuentes independientes y se determina la resistencia de entrada, que es la resistencia que se ve entre los terminales a y b. CASO 2: Cuando la red incorpore fuentes dependientes, continuar desactivando todas las fuentes independientes. Sin embargo, evite desactivar las fuentes dependientes ya que están controladas por variables del circuito. Vale la pena señalar que el valor de la resistencia de Thévenin (RTh) a veces puede ser negativo, lo que significa que el circuito suministra energía en lugar de consumirla. Este escenario es factible en circuitos con fuentes dependientes.

Teorema de Thevinin

El teorema de Thevenin establece que cualquier circuito lineal de dos terminales puede ser reemplazado por un circuito equivalente con una sola fuente de voltaje en serie con un ...

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Thevinin's Theorem

thevenin circuit equivalents

Thevenin circuit equivalents simplify linear two-terminal circuits by replacing the fixed part of a network with one equivalent source and one resistor. This method is useful when a circuit has a fixed section and a load that can change. A household electrical outlet is a familiar example, because different appliances can be plugged in or removed. Each change in load can require a new circuit analysis, so an equivalent circuit makes the work easier.

Thevenin's theorem states that a linear two-terminal circuit can be represented by a voltage source in series with a resistor. From the outside, this equivalent circuit has the same behavior as the original network. Two circuits are considered equivalent when they have the same voltage-current relationship at their terminals. The Thevenin equivalent voltage, VTh, is the open-circuit voltage at the terminals, and the Thevenin equivalent resistance, RTh, is the input resistance seen at the terminals when the independent sources are turned off.

To find the Thevenin resistance, the method depends on the kind of sources in the network. If the circuit has no dependent sources, all independent sources are deactivated and the resistance between terminals a and b is found. If the network includes dependent sources, the independent sources are still turned off, but the dependent sources stay active because they are controlled by circuit variables. In some cases, RTh can be negative. That means the circuit is supplying power instead of consuming it, which can happen in circuits with dependent sources.

Thevenin Circuit Equivalents

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Thevenin circuit equivalents simplify linear two-terminal circuits by replacing the fixed part of a network with one equivalent source and one resistor. This method is useful when a circuit has a fixed section and a load that can change. A household electrical outlet is a familiar example, because different appliances can be plugged in or removed. Each change in load can require a new circuit analysis, so an equivalent circuit makes the work easier. Thevenin's theorem states that a linear...

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Learn how Thevenin’s theorem replaces a linear two-terminal circuit with a voltage source and resistor, and how to find VTh and RTh in circuit analysis.

Thevenin Circuit Equivalents | 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

Thevenin Circuit Equivalents

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