Admittance

Admittance

To simplify mathematical manipulation, calculation, and analysis, it is sometimes convenient to express the impedance as its reciprocal quantity, or admittance. Admittance is defined as

Y = 1/Z = I/V

and can be written as

Y = G + jB

where G and B are the rectangular (real and imaginary) components, known as conductance and susceptance respectively. The conductance G is the reciprocal of the parallel resistance, as follows:

G = 1/R_P

The susceptance for capacitors is expressed as follows:

B_C = 2fC_P = 1/X_C

The susceptance for inductors is expressed as follows:

B_L = 1/2fL_P = 1/X_L