Inductive VTs, in common with any ferromagnetic
transformer, may cause or contribute to ferroresonance.
Therefore, it is important to include the VT saturation
characteristic in the model. An example of low frequency
ferroresonance involving a VT is presented in [8], in which a
66kV VT is represented using the traditional equivalent
circuit, with a resistive burden. The dominant frequency of
the transient simulated was 20 Hz.