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5.9:

Types of Responses of Series RLC Circuits

JoVE Core
Electrical Engineering
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JoVE Core Electrical Engineering
Types of Responses of Series RLC Circuits

Lingue

Condividere

A source-free series RLC circuit is represented by a second-order differential equation.

Its complete solution is a linear combination of two distinct solutions, each corresponding to the two roots expressed in terms of the damping factor and resonant frequency.

If the damping factor exceeds the resonant frequency, the roots are real and negative, leading to an overdamped response that decays over time.

When the damping factor equals the resonant frequency, the roots are equal.

In this scenario, the second-order differential equation reduces to a first-order with an exponential solution.

The natural response, a sum of a negative exponential and a negative exponential multiplied by a linear term, peaks at its time constant and then decays to zero, indicating critical damping.

If the damping factor is less than the resonant frequency, the complex roots can be expressed in terms of the damped natural frequency.

Euler's formula simplifies the complete response to functions of sine and cosine terms.

So, the natural response is underdamped and oscillatory with a time period proportional to the damped natural frequency.

5.9:

Types of Responses of Series RLC Circuits

A second-order differential equation characterizes a source-free series RLC circuit, marking its distinct mathematical representation. The complete solution of this equation is a blend of two unique solutions, each linked to the circuit's roots expressed in terms of the damping factor and resonant frequency.

Equation1

When the damping factor surpasses the resonant frequency, both roots are real and negative, leading to an overdamped response. In this scenario, the circuit's reaction gradually decays over time.

When the damping factor matches the resonant frequency, the second-order differential equation simplifies to a first-order equation with an exponential solution. The natural response follows a pattern of peaking at its time constant and then decaying to zero, signifying critical damping.

Equation2

For situations where the damping factor is less than the resonant frequency, complex roots emerge, characterized by the damped natural frequency. Euler's formula simplifies the complete response to sine and cosine functions, resulting in an underdamped and oscillatory natural response with a time period proportional to the damped natural frequency.

Equation3

These different response behaviors illustrate the significance of source-free RLC circuits in circuit analysis, offering intriguing insights into electrical circuit behavior and applications.