Name: phasors for ac circuit analysis
Uploaded: 2024-04-11T12:48:48.000Z
Duration: 1 min 12 s
Channel: JoVE

Los fasores son representaciones complejas de las sinusoides donde la magnitud del fasor es igual a la amplitud y el ángulo es igual a la fase medida desde el eje x positivo.
Simplifican el análisis de los circuitos de CA al eliminar la dependencia temporal de la corriente y el voltaje, transformando el circuito en su forma de CC equivalente.
Los fasores se pueden representar en formas rectangulares, polares o exponenciales mediante el uso de la identidad de Euler.
Para obtener el fasor de una sinusoide en forma sinusoidal, primero conviértelo en forma de coseno y luego exprésalo como la parte real del número complejo.
El fasor de esta sinusoide es igual a la parte independiente del tiempo del número complejo.
Por el contrario, la sinusoide de un fasor dado se obtiene multiplicando el fasor por el factor tiempo y tomando su parte real.
Los fasores se pueden representar como vectores giratorios o sinores en sentido contrario a las agujas del reloj en un plano complejo con una frecuencia angular constante, y los diagramas que los representan se conocen como diagramas de fasor.
La proyección de los senos giratorios en el eje real representa los sinusoides.

fasores

Los fasores son una poderosa herramienta matemática que se utiliza para analizar circuitos de corriente alterna (CA). Proporcionan una representación de números complejos de sinusoides, donde la magnitud del fasor equivale a la amplitud de la sinusoide y el ángulo del fasor representa la fase medida desde el eje x positivo. Uno de los beneficios importantes del uso de fasores es que simplifican el análisis de circuitos de CA al eliminar la dependencia temporal de la corriente y el voltaje. Esta transformación permite analizar un circuito de CA como si fuera su forma equivalente de corriente continua (CC), lo que hace que los cálculos sean más sencillos. Los fasores se pueden representar en diferentes formas (rectangulares, polares o exponenciales) utilizando la identidad de Euler, una fórmula fundamental en el análisis complejo que establece una relación profunda entre funciones trigonométricas y exponenciales. Para obtener el fasor de una sinusoide en forma seno, primero hay que convertirlo a coseno y luego expresarlo como la parte real de un número complejo. El fasor de esta sinusoide es igual a la parte independiente del tiempo de este número complejo. Por el contrario, la sinusoide de un fasor dado se puede obtener multiplicando el fasor por un factor de tiempo y tomando su parte real. En un contexto gráfico, los fasores se pueden visualizar como vectores giratorios, o 'senores', que giran en sentido contrario a las agujas del reloj en un plano complejo con una frecuencia angular constante. Los diagramas que representan estos senores giratorios se conocen como diagramas fasoriales. Un concepto clave para comprender el diagrama fasor es que la proyección de los senores giratorios sobre el eje real representa las sinusoides. Esto significa que la posición horizontal del senor en cualquier momento corresponde al valor instantáneo de la función sinusoidal que representa.

Fasores

Los fasores son representaciones complejas de los sinusoides en las que la magnitud del fasor es igual a la amplitud y el ángulo es igual a la fase medida desde ...

Education

Educación

JoVE Core

Electrical Engineering

Ingeniería Eléctrica

Unit 1

Unidad 1

AC Circuit Analysis

Análisis de circuitos de corriente alterna (CA)

KEY TERMS AND CONCEPTS

TÉRMINOS Y CONCEPTOS CLAVE

Phasors

phasors for ac circuit analysis

Phasors are a mathematical tool for analyzing alternating current, or AC, circuits. They represent sinusoids with complex numbers. The phasor magnitude matches the sinusoid amplitude, and the phasor angle shows the phase measured from the positive x-axis.

Phasors make AC circuit analysis simpler by removing time from the current and voltage expressions. That lets an AC circuit be treated like its equivalent direct current, or DC, form for calculations. Phasors can also be written in rectangular, polar, or exponential form.

Euler’s identity links trigonometric functions and exponential functions, and it helps convert between these phasor forms. To find the phasor of a sinusoid in sine form, the signal is first written in cosine form. It is then expressed as the real part of a complex number, and the phasor is the time-independent part of that number.

A sinusoid can also be recovered from a phasor. The phasor is multiplied by a time factor, and then the real part is taken. In a graph, phasors appear as rotating vectors, or sinors, on the complex plane.

These rotating sinors move counterclockwise with constant angular frequency. The diagrams that show them are called phasor diagrams. The projection of a sinor onto the real axis gives the sinusoid, so the horizontal position at any moment shows the instantaneous value of the wave.

Phasors for AC Circuit Analysis

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phasors

Phasors are a mathematical tool for analyzing alternating current, or AC, circuits. They represent sinusoids with complex numbers. The phasor magnitude matches the sinusoid amplitude, and the phasor angle shows the phase measured from the positive x-axis. Phasors make AC circuit analysis simpler by removing time from the current and voltage expressions. That lets an AC circuit be treated like its equivalent direct current, or DC, form for calculations. Phasors can also be written in...

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key terms and concepts

Learn how phasors represent AC sinusoids, simplify circuit analysis, and appear as rotating vectors on the complex plane in phasor diagrams.

Phasors for AC Circuit Analysis | 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

Phasors for AC Circuit Analysis

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