Resonance currents. Definition formulas, vector diagram

The mode in which the circuit containing parallel branches with inductive and capacitive elements, the current unbranched part of the circuit coincides in phase with the voltage (φ = 0), is called the resonance currents.

Current resonance condition:



B1 - reactive conductivity of the first branch,
B2 - reactive conductivity of the second branch

Signs of current resonance:
The reactive components of the branch currents are IPC = IPL and are out of phase in the case when the input voltage is purely active;
The currents of the branches exceed the total current of the circuit, which has a minimum value;
and match in phase

Resonance frequency



Cases of resonant circuits



If R2 = 0 resonance occurs when

Current resonance cases
Case 1. One resonance in the circuit, provided:



Case 2. Two resonances in the circuit, at a certain ratio of the resistances of the elements.



Case 3. No resonance in the circuit - the frequency is an indefinite value, with



Frequency characteristics of the oscillating circuit