Components of Admittance. ( Simple Explanation)

Components of Admittance. ( Simple Explanation)

Components of Admittance.

Conductance:

A component of admittance inphase with the applied voltage is called conductance. Or the X component of admittance is called conductance. It’s represented by G and the unit of conductance is Mho or Siemens.

G = Y Cos φ = (1/Z) * (R/Z) = R/Z² = R/ (R² + X²)

(Since Cos φ = R/Z and Y = 1/Z)

And Total Conductance G_T = G₁ +G₂ +G_3+…..

Susceptance:

That component of admittance, which has an angle of 90 degree with applied voltage is called suserptance. ..or Y component of admittance is celled susceptnce, its represented by B. and the unit of susceptance is also Mho or Siemens.

OR

A Component of admittance in quadrature ( at 90 degree) with the applied Voltage is called susceptance.

B = Y Sin Φ = 1/Z * X/Z = X/Z² = X/ (R² + X²) --------> (Since Sine Φ  = X/Z)

And total Susceptance = B_T = B₁ + B₂ + B₃ +…B_n

Also Note that inductive suseptance of a wiring is negative (-), while Capacitive Susceptance of a wiringis always positive (+).

Y = G - j B_L …… (In case of inductive Circuit)

Y = G + B_C ....... (In case of capacitive wiring)

For More explanation, consider the following wiring, (fig 1)

 

The Total conductance = algebraic sum of the conductance in each branch.

The Total conductance =G_T= G₁ +G₂ +G₃

Similarly,

Total susceptance = algebraic sum of the susceptance in each branch,

Total susceptance B_T = (-B₁) + (-B₂) + (B₃).

And total wiring admittance,

Y_T = √ (G_T² + B_T²)

In case of inductive Circuit Y_T = √ (G² + B_L²) and Phase angle φ tan^-1 (-B_L/G)

In Case of Capacitive Circuit Y_T = √ (G² + B_L²) and phase angle φ tan^-1 (B_c /G)

And Total current, I = VY,

And Power factor = Cos φ = G/Y.