Name: matching load impedance for maximum power
Uploaded: 2024-07-08T13:19:54.000Z
Duration: 1 min 20 s
Channel: JoVE

Considere un circuito lineal de CA conectado a una carga, representado por su equivalente Thevenin.
La corriente que fluye a través de la carga se determina utilizando la forma rectangular de Thevenin y la impedancia de carga.
La potencia media suministrada a la carga se obtiene a partir de la expresión actual.
Para determinar la resistencia de carga para la potencia máxima, la derivada de la potencia con respecto a la resistencia para la potencia máxima se establece como cero.
Del mismo modo, se obtiene la reactancia de carga para la máxima potencia.
Por lo tanto, para la transferencia de potencia promedio máxima, la reactancia de la impedancia de carga es el negativo de la reactancia de la impedancia de Thevenin, y su resistencia es igual a la resistencia de la impedancia de Thevenin.
Sustituyendo estos valores, se obtiene la máxima potencia.
De acuerdo con el teorema de potencia media máxima, la impedancia de carga es igual al conjugado complejo de la impedancia de Thevenin.
Para cargas puramente resistivas, la transferencia de potencia promedio máxima ocurre cuando la impedancia de carga es igual a la magnitud de la impedancia de Thevenin.
En las comunicaciones inalámbricas, la impedancia de la antena se adapta a la impedancia de la línea de transmisión o del circuito receptor, lo que maximiza la transferencia de potencia, garantiza una intensidad de señal óptima y mejora la calidad y el alcance de la comunicación.

el teorema de la transferencia máxima de potencia

Considere un circuito lineal equivalente de Thevenin de CA conectado a una impedancia de carga.
<img alt="Equation 1" src="/files/ftp_upload/15125/15125_Equation_1.svg" style="height: 18px;">
La carga conectada extrae la corriente y el circuito entrega la potencia a la carga. La corriente alterna que fluye a través de la carga se determina utilizando la forma rectangular de voltajes, corrientes, impedancia de red e impedancia de carga. La potencia promedio entregada a la carga se obtiene del producto del cuadrado de la corriente y la resistencia de la carga.
<img alt="Equation 1" src="/files/ftp_upload/15125/15125_Equation_1.svg" style="height: 18px;">
<img alt="Equation 2" src="/files/ftp_upload/15125/15125_Equation_2.svg" style="height: 18px;">
La máxima transferencia de potencia entregada a la carga se determina calculando la derivada de potencia con respecto a la resistencia de la carga. Luego, la derivada se iguala a cero para la condición máxima. Entonces, para una transferencia de potencia promedio máxima, la reactancia de la impedancia de carga es el negativo de la reactancia de la impedancia de Thevenin, y su resistencia es igual a la resistencia de la impedancia de Thevenin. Cuando se cumplen estas condiciones, se dice que la impedancia de carga es el conjugado complejo de la impedancia de Thevenin del circuito. La potencia máxima se obtiene cuando la impedancia de carga cumple la condición mencionada anteriormente.
<img alt="Equation 3" src="/files/ftp_upload/15125/15125_Equation_3.svg" style="height: 46px;">
<img alt="Equation 4" src="/files/ftp_upload/15125/15125_Equation_4.svg" style="height: 38px;">
<img alt="Equation 5" src="/files/ftp_upload/15125/15125_Equation_5.svg" style="height: 18px;">
Según el teorema de la potencia media máxima, la impedancia de carga es igual al conjugado complejo de la impedancia de Thevenin. Para cargas puramente resistivas, la transferencia de potencia promedio máxima ocurre cuando la impedancia de la carga es igual a la magnitud de la impedancia de Thevenin.
En las comunicaciones inalámbricas, la impedancia de la antena se adapta a la impedancia de la línea de transmisión o del circuito receptor, lo que maximiza la transferencia de energía, garantiza una intensidad de señal óptima y mejora la calidad y el alcance de la comunicación.

El teorema de la transferencia máxima de potencia

Considere un circuito lineal de CA conectado a una carga, representado por su equivalente Thevenin.
La corriente que fluye a través de la carga se determina ...

Education

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JoVE Core

Electrical Engineering

Ingeniería Eléctrica

Unit 1

Unidad 1

AC Steady State Power

Potencia de corriente alterna en estado estacionario

KEY TERMS AND CONCEPTS

TÉRMINOS Y CONCEPTOS CLAVE

The Maximum Power Transfer Theorem

matching load impedance for maximum power

Maximum power transfer in an AC circuit depends on matching the load impedance to the Thevenin equivalent of the source network. The load draws current, and the circuit delivers power to that load. To analyze the current, the voltages, currents, network impedance, and load impedance are written in rectangular form.

The average power delivered to the load comes from the square of the current multiplied by the load resistance. To find the condition for maximum power, the power is differentiated with respect to the load resistance. That derivative is then set equal to zero.

For maximum average power transfer, the load reactance must be the negative of the Thevenin reactance. The load resistance must also equal the Thevenin resistance. When both conditions are met, the load impedance is the complex conjugate of the circuit's Thevenin impedance.

For a purely resistive load, maximum average power transfer occurs when the load impedance equals the magnitude of the Thevenin impedance. This idea is used in wireless communications, where an antenna is matched to a transmission line or receiver circuit. Good matching improves power transfer, signal strength, communication quality, and range.

Matching Load Impedance for Maximum Power

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the maximum power transfer theorem

Maximum power transfer in an AC circuit depends on matching the load impedance to the Thevenin equivalent of the source network. The load draws current, and the circuit delivers power to that load. To analyze the current, the voltages, currents, network impedance, and load impedance are written in rectangular form. The average power delivered to the load comes from the square of the current multiplied by the load resistance. To find the condition for maximum power, the power is differentiated...

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Learn how AC load impedance matching and complex conjugate conditions help maximize power transfer in Thevenin equivalent circuits and wireless communication.

Matching Load Impedance for Maximum Power | 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

Matching Load Impedance for Maximum Power

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