The equivalent harmonic impedances associated with time-variant device
s such as FACTs and HVdc converters are in many cases phase dependent.
The second rank tensor is proposed as a means of performing the nodal
analysis of networks incorporating phase dependent admittances. A use
ful geometric interpretation of phase dependency is developed, and app
lied to the calculation of the harmonic phase dependent impedance of a
HVdc converter on the ac side.