Name: ac source conversion in circuit analysis
Uploaded: 2024-04-11T12:48:49.000Z
Duration: 1 min 11 s
Channel: JoVE

Si consideri un circuito composto da una sorgente di corrente e una combinazione di resistori, condensatori e induttori con valori di impedenza noti.
L'obiettivo è quello di utilizzare la tecnica di trasformazione della sorgente per determinare la caduta di tensione attraverso il ramo più a destra del circuito.
Utilizzando la trasformazione della sorgente, una sorgente di corrente in parallelo con un'impedenza può essere convertita in una sorgente di tensione in serie con la stessa impedenza o viceversa.
Applicando la legge di Ohm, viene calcolata la tensione della sorgente. Questo valore può quindi essere espresso in termini di fasori.
Nel circuito trasformato, l'impedenza è in serie con la sorgente di tensione, insieme agli altri due elementi del ramo superiore. Si ottiene l'impedenza di serie equivalente.
Ora, la tecnica di trasformazione della sorgente viene applicata di nuovo per riconvertire la sorgente di tensione in una sorgente di corrente.
Successivamente, si ottiene l'impedenza della nuova combinazione in parallelo, che viene utilizzata per trasformare la sorgente di corrente in una sorgente di tensione.
Infine, la regola di divisione della tensione determina la caduta di tensione attraverso il ramo più a destra.

trasformazione della sorgente per circuiti ca

Il processo di trasformazione della sorgente nel dominio della frequenza, comporta la conversione di una sorgente di tensione, posizionata in serie ad un'impedenza, in una sorgente di corrente parallela ad un'impedenza, o viceversa. È essenziale mantenere le seguenti relazioni durante la transizione da un tipo di origine a un altro.

<img alt="Equation1" src="/files/ftp_upload/15112/15112_PT_Equation_1.svg" style="text-align: center; height: 16px;">
<img alt="Equation2" src="/files/ftp_upload/15112/15112_PT_Equation_2.svg" style="text-align: center; height: 40px;">

Per determinare la tensione sconosciuta per un circuito, composto da una sorgente di corrente e un insieme di resistori, condensatori e induttori, ciascuno con la propria impedenza nota distinta, vengono seguiti una serie di passaggi. Inizialmente, la sorgente di tensione viene convertita in una sorgente di corrente e vengono stabiliti i valori della corrente della sorgente (Ⅰs) e dell'impedenza (Zs).

Successivamente, ritrasformando la sorgente di corrente in una sorgente di tensione, si ottiene un circuito diverso. Da questo circuito derivato, si calcola la tensione sorgente (Vs) utilizzando i valori precedentemente determinati. Infine, applicando la regola della divisione della tensione, è possibile identificare la tensione sconosciuta ai capi della resistenza.

Trasformazione della Sorgente per Circuiti CA

Si consideri un circuito composto da una sorgente di corrente e una combinazione di resistori, condensatori e induttori con valori di impedenza noti.
L'obiettivo è quello di ...

Education

Didattica

JoVE Core

Electrical Engineering

Ingegneria elettrica

Unit 1

Unità 1

AC Circuit Analysis

Analisi dei circuiti in CA

KEY TERMS AND CONCEPTS

TERMINI E CONCETTI CHIAVE

Source Transformation for AC Circuits

ac source conversion in circuit analysis

AC source conversion is a circuit analysis method used in the frequency domain. It changes a voltage source in series with an impedance into a current source in parallel with the same impedance, or it converts a current source back into a voltage source. The source values must keep the correct relationship during each change.

This method helps solve for an unknown voltage in a circuit that includes a current source and components such as resistors, capacitors, and inductors. Each of these parts has a known impedance. The circuit is handled in steps so the final voltage can be found more easily.

First, the voltage source is converted into a current source. The source current, Is, and the source impedance, Zs, are identified. Next, the current source is changed back into a voltage source, which gives a new circuit form. From that derived circuit, the source voltage, Vs, is calculated. The final unknown voltage across the resistor is then found with the voltage division rule.

AC Source Conversion in Circuit Analysis

sinusoidal sources

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graphical and analytic representation of sinusoids

graphical-and-analytic-representation-of-sinusoids

Measuring Sinusoid Phase on an Oscilloscope

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phasors

Phasors for AC Circuit Analysis

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Phasor Rules for AC Circuit Analysis

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AC Circuit Phasors: Resistor, Inductor, Capacitor

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AC Circuit Rules with Phasor Diagrams

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impedances and admittance

AC Circuit Response: Impedance and Admittance

AC circuit response changes with frequency, and impedance describes how resistors, inductors, and capacitors affect sinusoidal current flow. In phasor form, voltage and current are used to show this behavior in a clear way. Impedance is a key idea in AC circuit analysis because it measures opposition to current in an alternating circuit. These components behave differently in AC than in DC. In DC circuits, inductors act like short circuits and capacitors act like open circuits. In AC circuits,...

impedance combination

Series and Parallel Impedance Rules

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AC Circuit Node Method in an Angioplasty Model

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Impedance Matching with Mesh Currents

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source transformation for ac circuits

AC source conversion is a circuit analysis method used in the frequency domain. It changes a voltage source in series with an impedance into a current source in parallel with the same impedance, or it converts a current source back into a voltage source. The source values must keep the correct relationship during each change. This method helps solve for an unknown voltage in a circuit that includes a current source and components such as resistors, capacitors, and inductors. Each of these...

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Norton Current in AC Circuit Analysis

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key terms and concepts

Learn how AC source conversion turns voltage sources into current sources and back again to find unknown voltage with impedance and voltage division.

AC Source Conversion in 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

AC Source Conversion in Circuit Analysis

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