Page 401 - Basic Electrical Engineering

has been shown separately. The phasor diagram of voltage and current
components have been shown in Fig. 3.69 (b). The line current I is equal to
the in-phase component of I with the voltage V, i.e., I = I cos ϕ . At
L
L
L
resonance, the current through the capacitor I is balanced by I sin ϕ as
C
L
shown. Thus, the reactive component of line current which is the phasor sum
of I and I sin ϕ is zero. The condition for resonance is
C
L
L

IL sin ϕ = I C
L

or,

The condition of resonance is

To calculate resonance frequency, f we take,
0

or,

or,

or,

or,

or,

or,