Resonance Circuits Part II -...
Transcript of Resonance Circuits Part II -...
Dr. Mohamed Refky Amin
Electronics and Electrical Communications Engineering Department (EECE)
Cairo University
http://scholar.cu.edu.eg/refky/
Resonance Circuits
Part II
Outline of This Lecture
• Previously on ELC 1030
• Examples on Series Resonance Circuits
• Parallel Resonance Circuits
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Previously on ELC 1030
In physics, resonance is the tendency of a system to oscillate with
greater amplitude at some frequencies than at others.
Frequency at which the response amplitude is a maximum is
known as the system's resonant frequency, or resonance frequency
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Definition of Resonance
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Previously on ELC 1030
For electric circuit to resonate, the circuit must have L, and C
elements.
Resonance is a condition in an RLC circuit in which the capacitive
and inductive reactances are equal in magnitude, thereby resulting
in a purely resistive impedance.
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Resonance in Electrical Circuits
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Previously on ELC 1030
Series Resonance Circuit Parallel Resonance Circuit
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Types of Resonance Circuits
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Resonant circuits (series or parallel) are useful for constructing
filters, as their transfer functions can be highly frequency selective.
They are used in many applications such as selecting the desired
stations in radio and TV receivers.
Previously on ELC 1030
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Applications of Resonance Circuits
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Previously on ELC 1030
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General Expression for the Current
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Previously on ELC 1030
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Previously on ELC 1030
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Previously on ELC 1030
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Previously on ELC 1030
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Previously on ELC 1030
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Previously on ELC 1030
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Previously on ELC 1030
Resonance at
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in rad/s in Hz
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Series Resonance
Example (1)
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Series Resonance
Example (2)
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Series Resonance
Example (3)
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Series Resonance
Example (4)
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Series Resonance
Example (5)
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Parallel Resonance
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Ideal Parallel Circuit
Parallel Resonance
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In parallel circuits, at resonance,
the capacitor and the coil are
replaced by an Open Circuit.
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Ideal Parallel Circuit
Parallel Resonance
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Quality Factor of a Real Coil
Parallel Resonance
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Parallel Resonance
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The Equivalent All-Parallel Circuit
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Parallel Resonance
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The Equivalent All-Parallel Circuit
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Parallel Resonance
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The Equivalent All-Parallel Circuit
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Parallel Resonance
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The Equivalent All-Parallel Circuit
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Parallel Resonance
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The Equivalent All-Parallel Circuit
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Parallel Resonance
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Parallel Resonance
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• Impedance & voltage in terms of quality factor
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Parallel Resonance
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Parallel Resonance
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Parallel Resonance
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Bandwidth and Cut-off Frequencies
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Parallel Resonance
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Bandwidth and Cut-off Frequencies
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Parallel Resonance
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Bandwidth and Cut-off Frequencies
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Parallel Resonance
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Bandwidth and Cut-off Frequencies
a b c
1
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Parallel Resonance
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Bandwidth and Cut-off Frequencies
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Parallel Resonance
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Parallel Resonance
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Parallel Resonance
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In general:
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Resonance at
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Parallel Resonance