Name: load matching in thevenin circuits
Uploaded: 2024-04-11T12:48:31.000Z
Duration: 1 min 16 s
Channel: JoVE

En aplicaciones prácticas, un circuito está diseñado para entregar la máxima potencia desde una fuente a una carga.
Un circuito equivalente a Thevenin puede determinar la potencia máxima que puede entregar un circuito lineal.
La potencia suministrada es el producto de la resistencia de carga y el cuadrado de la corriente. Varía a medida que cambia la resistencia de la carga.
Para identificar el valor de resistencia a la carga que maximiza la potencia, se utiliza el cálculo diferencial. Simplificando esta ecuación, se proporciona el valor óptimo de resistencia a la carga.
Este valor de resistencia se sustituye en la segunda derivada de la potencia, lo que da como resultado un valor negativo, lo que confirma la condición para la potencia máxima.
El valor de resistencia obtenido permite el cálculo de la potencia máxima. Si la resistencia de carga no coincide con la resistencia de Thevenin, la potencia real suministrada se desviará de este máximo.
De acuerdo con el Teorema de Transferencia de Potencia Máxima, la transferencia de potencia más alta ocurre cuando la resistencia de carga coincide con la resistencia de Thevenin.
Considere una batería de parámetros conocidos, conectada con dos resistencias de valores conocidos. La resistencia que coincide con la resistencia interna de la batería recibe la máxima potencia.

transferencia de potencia máxima

Numerosas aplicaciones prácticas dentro de disciplinas de ingeniería, como las telecomunicaciones, requieren optimizar la entrega de energía a una carga conectada. Sin embargo, esta búsqueda implica pérdidas internas inherentes, que pueden igualar o exceder la potencia suministrada a la carga. El circuito equivalente de Thevenin es útil para encontrar la potencia máxima que un circuito lineal puede entregar a una carga. En este contexto se parte del supuesto de que la resistencia de carga se puede ajustar. Al sustituir todo el circuito con su equivalente de Thevenin preservando al mismo tiempo la carga como se muestra en la Figura 1, <img alt="Figure1" src="/files/ftp_upload/15055/15055_PT_Figure_1.svg" style="text-align: center; height: 140px;"> Figure 1: Circuito utilizado para máxima transferencia de potencia.  La potencia entregada a la carga está dada por <img alt="Equation1" src="/files/ftp_upload/15055/15055_PT_Equation_1.svg" style="text-align: center; height: 40px;">.................(1) Para un circuito dado, la resistencia y el voltaje equivalentes de Thevenin son fijos. La variación de la potencia entregada a la carga con resistencia de carga es pequeña para valores pequeños o grandes de resistencia de carga, pero máxima para algún valor de resistencia de carga entre cero e infinito. La potencia máxima se produce cuando la resistencia de la carga es igual a la resistencia de Thevenin expresada como <img alt="Equation2" src="/files/ftp_upload/15055/15055_PT_Equation_2.svg" style="text-align: center; height: 14px;">.................(2) Esto se conoce como teorema de máxima transferencia de potencia. Utilizando las ecuaciones 1 y 2, se obtiene la expresión de potencia máxima transferida y se expresa como <img alt="Equation3" src="/files/ftp_upload/15055/15055_PT_Equation_3.svg" style="text-align: center; height: 40px;">..................(3) Esta ecuación se aplica solo cuando la ecuación 2 es válida; de lo contrario, la potencia entregada a la carga se determina usando la ecuación. 1.

Transferencia de potencia máxima

En aplicaciones prácticas, un circuito está diseñado para entregar la máxima potencia desde una fuente a una carga.
Un circuito equivalente a Thevenin puede determinar el valor máximo ...

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JoVE Core

Electrical Engineering

Ingeniería Eléctrica

Unit 1

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DC Circuit Analysis

Análisis de circuitos de CC

KEY TERMS AND CONCEPTS

TÉRMINOS Y CONCEPTOS CLAVE

Maximum Power Transfer

load matching in thevenin circuits

Load matching in Thevenin circuits helps a source deliver the most power to a connected load. This matters in engineering fields such as telecommunications, where power delivery must be optimized. Even then, internal losses can be significant and may equal or exceed the power sent to the load.

The Thevenin equivalent circuit is a useful way to study this situation. It replaces the full linear circuit with a simpler source and resistance while keeping the load in place. In this setup, the load resistance is assumed to be adjustable, so the power delivered to it can be tested across different values.

For a fixed circuit, the Thevenin equivalent voltage and resistance do not change. The load power changes only a little when the load resistance is very small or very large. It reaches a maximum at one value between zero and infinity.

The maximum power occurs when the load resistance equals the Thevenin resistance. This condition is called the maximum power transfer theorem. Using the load-power equation and this matching rule, the maximum transferred power can be found. If the matching condition is not met, the load power is determined from the general power equation instead.

Load Matching in Thevenin Circuits

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Load matching in Thevenin circuits helps a source deliver the most power to a connected load. This matters in engineering fields such as telecommunications, where power delivery must be optimized. Even then, internal losses can be significant and may equal or exceed the power sent to the load. The Thevenin equivalent circuit is a useful way to study this situation. It replaces the full linear circuit with a simpler source and resistance while keeping the load in place. In this setup, the load...

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Learn how Thevenin equivalent circuits predict maximum power transfer when load resistance matches Thevenin resistance in linear circuits.

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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

Load Matching in Thevenin Circuits

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