The Voltage Source Model 1 allows impedance entry for both positive and negative sequence (i.e. main phase and neutral) impedance. The following describe some of the data entry options.
The positive sequence source impedance may be chosen as one of the 4 following types:
R: Purely resistive
L: Purely inductive
R//L: Parallel RL
R-R//L: Parallel RL in series with a resistance
The zero-sequence (neutral) impedance may be entered only as a parallel R//L.
Impedance quantities for both positive and zero sequence may be entered directly as lumped R an L values, or in polar format (i.e. magnitude and phase). This is controlled by the Impedance Data Format input parameter. The options are entitled RRL Values and Impedance respectively.
Of particular importance is when the source impedance is chosen as R-R//L to be entered in Impedance format:
An equivalent parallel RL in series with a resistance cannot be constructed simply from the magnitude and phase information alone. Therefore, an additional input called Harm. # where phase is same as fund., is included. This input is simply the harmonic number of the frequency, where the phase angle of the impedance at that frequency is the same as that at the fundamental. That is when:
