Page 405 - Basic Electrical Engineering

Current at resonance (Acceptor type)

Minimum, I = (Rejector type)
0

Impedance at resonance Minimum, Z = R Maximum, Z = L/CR
0
0
Power factor at resonance Unity Unity

Resonant frequency

Magnification element Voltage Current

Magnification factor or Q-
factor

Bandwidth of parallel resonant circuit

Bandwidth of a parallel resonant circuit is determined the same way as in the

case of the series resonant circuit. Bandwidth is the range of frequencies (f –
2
f ) where the power dissipated is half of the power dissipated at the resonant
1
frequency.
The critical parameters of series and parallel resonant circuits have been

compared and shown in Table 3.1
We have seen that resonance in ac series and parallel circuits can take

place at a particular frequency when a constant voltage, variable frequency
supply source is applied across the circuit. The frequency at which resonance

occurs are

and