Recalling that the current phasor associated with a sinusoidal variation in charge is expressed as
It is apparent that
An alternate expression for the charging current is
Therefore, the charging admittance (which is pure susceptance) must be
The preceding discussion suggests a computational procedure for determining the capacitive parameters of a conductor configuration:
Compute the configuration’s potential matrix P using Equation 33.
Compute its capacitance matrix C by inverting P.
Multiply the capacitance matrix C by the scalar j to obtain the shunt admittance matrix Yshunt.
Invert the the shunt admittance matrix Yshunt to determine the capacitive reactance Xshunt.