Name: analyzing circuits with superposition
Uploaded: 2024-04-11T12:48:31.000Z
Duration: 1 min 18 s
Channel: JoVE

The superposition theorem is used in circuits with multiple independent sources.
To apply this theorem, keep one independent source at a time while replacing the inactive voltage source with a short-circuit and the inactive current source with an open-circuit, respectively.
The theorem states that the voltage across or the current through an element in a linear circuit is the algebraic sum of the contributions from the independent sources.
Consider a circuit with a voltage and a current source, where the voltage drop across a resistor must be determined.
The voltage drop has contributions from both independent sources.
The contribution of the voltage source is obtained by setting the current source to zero.
By applying Kirchhoff&#39;s voltage law, the loop current is determined. Using Ohm&#39;s law, the voltage drop is calculated.
Similarly, the current source contribution is obtained by setting the voltage source to zero.
Combining the resistors, the equivalent resistance is obtained. Using the current division rule and Ohm&#39;s law, the voltage drop is determined.
Finally, by adding the contributions from independent sources, the total voltage drop across the resistor is obtained.

superposition theorem

The superposition principle is a fundamental concept stating that in a linear circuit, the voltage across (or current through) an element can be determined by summing the individual contributions of each independent source acting in isolation. When dealing with linear circuits containing multiple independent sources, this principle serves as a valuable tool for analysis. To apply the superposition principle effectively, one should focus on a single independent source at a time while deactivating all others. This approach yields the output (voltage or current) resulting from the active source.
The cumulative effect of all active sources can then be determined by algebraically adding their individual contributions. This simplifies the circuit analysis process. Notably, dependent sources remain unaffected as they are governed by circuit variables. It is worth noting that utilizing the superposition principle can lead to increased analytical effort. For example, when dealing with a circuit featuring three independent sources, one must analyze three separate, simplified circuits, each representing the contribution of an individual source. Despite this potential drawback, the superposition principle remains a valuable technique for simplifying complex circuits by replacing voltage sources with short circuits and current sources with open circuits.

Superposition Theorem

The superposition theorem is used in circuits with multiple independent sources.
To apply this theorem, keep one independent source at a time while ...

Education

JoVE Core

Electrical Engineering

Unit 1

DC Circuit Analysis

KEY TERMS AND CONCEPTS

analyzing circuits with superposition

Superposition is a circuit analysis method for linear circuits with more than one independent source. It lets you find the voltage across or current through an element by adding the separate effects of each source acting alone.

To use superposition, keep one independent source active and turn off the others. A voltage source is replaced by a short circuit, and a current source is replaced by an open circuit. Then calculate the output from the single active source.

Repeat the process for each independent source in the circuit. The final voltage or current is found by algebraically adding the individual results. Dependent sources are not turned off because they depend on circuit variables.

This method can simplify complex circuits, but it may take more work. A circuit with three independent sources must be analyzed as three separate simplified circuits. Even so, superposition remains a useful tool for breaking down difficult linear circuit problems.

Analyzing Circuits with Superposition

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Superposition is a circuit analysis method for linear circuits with more than one independent source. It lets you find the voltage across or current through an element by adding the separate effects of each source acting alone. To use superposition, keep one independent source active and turn off the others. A voltage source is replaced by a short circuit, and a current source is replaced by an open circuit. Then calculate the output from the single active source. Repeat the process for each...

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key terms and concepts

Learn how superposition helps solve linear circuits by analyzing one independent source at a time, then adding the voltage or current contributions.

Analyzing Circuits with Superposition | 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

Analyzing Circuits with Superposition

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