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Parallel resonance
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Impedance is maximum at resonance.
In a parallel LC circuit at resonance the impedance is maximum and the line current minimum (rejector circuit). Used in filters.
Tank circuit of oscillators.
Opposite of series resonance.
In more detail
In a parallel LCR circuit, resonance occurs when the inductive and capacitive currents cancel, making the total impedance maximum. The total current from the source is minimal at that frequency.
Real-world uses
- Parallel resonance is used in notch filters to remove a frequency.
- Antenna matching circuits use parallel resonance.
- Filter circuits use parallel resonance to block a particular frequency, where the impedance peaks.
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Frequently asked questions
How does it differ from series?
In parallel resonance, impedance is maximum, while in series resonance it is minimum.
What frequency is it at?
The same as series resonance for an ideal LC pair.
How does parallel resonance differ from series?
At parallel resonance, the impedance is at its maximum, so the circuit blocks the current at that frequency.
Related topics in AC Circuits & EM Waves
Power factor · Wattless current · LC oscillations · Filters · Transformers in power transmission · Three-phase power