Parallel Resonance - Cairo...

Parallel Resonance

Dr. Mohamed Refky Amin

Electronics and Electrical Communications Engineering Department (EECE)

Cairo University

elc.n112.eng@gmail.com

http://scholar.cu.edu.eg/refky/

OUTLINE

• Previously on ELC N112

• Analysis of Parallel Resonance Circuits

• Quality Factor of a Coil

• Solved Examples

2Dr. Mohamed Refky

Previously on ELC N112

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

Dr. Mohamed Refky

Definition of Resonance

Previously on ELC N112

Series resonance Parallel resonance

Dr. Mohamed Refky

Previously on ELC N112

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Current Expression in Series Resonance

Previously on ELC N112

Dr. Mohamed Refky

Previously on ELC N112

Dr. Mohamed Refky

Previously on ELC N112

Resonance at

-

in rad/s in Hz

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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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• Impedance & voltage in terms of quality factor

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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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Bandwidth and Cut-off Frequencies

a b c

1

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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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In general:

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Resonance at

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Parallel Resonance

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Example (1)

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Example (2)

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Example (3)

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Example (4)

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