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

Consider a circuit composed of a current source and a combination of resistors, capacitors, and inductors with known impedance values.
The aim is to utilize the source transformation technique to determine the voltage drop across the circuit&#39;s right-most branch.
Using source transformation, a current source in parallel with an impedance can be converted into a voltage source in series with the same impedance or vice-versa.
By applying Ohm&#39;s law, the source voltage is calculated. This value can then be expressed in terms of phasor.
In the transformed circuit, the impedance is in series with the voltage source, along with the other two elements of the top branch. The equivalent series impedance is obtained.
Now, the source transformation technique is applied again to convert the voltage source back into a current source.
Next, the impedance of the new parallel combination is obtained, which is utilized to transform the current source back into a voltage source.
Finally, the voltage division rule determines the voltage drop across the right-most branch.

source transformation for ac circuits

The process of source transformation in the frequency domain entails the conversion of a voltage source, positioned in series with an impedance, into a current source that is parallel to an impedance, or the other way around. It is essential to maintain the following relationships while transitioning from one source type to another.
<img alt="Electrical impedance formula Vs=ZsIs equation for circuit analysis." src="/files/ftp_upload/15112/15112_PT_Equation_1.svg" style="text-align: center; height: 16px;" data-altupdatedat="1762173717000" data-alt="Equation1" />
<img alt="Equation illustrating electrical current in a circuit; formula: I&#60;sub&#62;S&#60;/sub&#62;=V&#60;sub&#62;S&#60;/sub&#62;/Z&#60;sub&#62;S&#60;/sub&#62;." src="/files/ftp_upload/15112/15112_PT_Equation_2.svg" style="text-align: center; height: 40px;" data-altupdatedat="1762173717000" data-alt="Equation2" />
In order to determine the unknown voltage for a circuit composed of a current source and a collection of resistors, capacitors, and inductors - each with their distinct known impedance, a series of steps are followed. Initially, the voltage source is converted into a current source, and the values of the source current (Is) and impedance (Zs) are established.
Subsequently, transforming the current source back to a voltage source results in a different circuit. From this derived circuit, the source voltage (Vs) is calculated using the previously determined values. Finally, by applying the voltage division rule, the unknown voltage across the resistance can be identified.

Source Transformation for AC Circuits

Consider a circuit composed of a current source and a combination of resistors, capacitors, and inductors with known impedance values.
The aim is to ...

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JoVE Core

Electrical Engineering

Unit 1

AC Circuit Analysis

KEY TERMS AND CONCEPTS

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

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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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