External equivalent (impedance source)
I have a wind equivalet generator, a step-up transformer, collector systems, main transformer and a swing bus linked through an ideal line to the HV trasformer bus. For voltage reference step in a plant controller: "The determination of the external system strength (source impedance) at the time of the testing was essential for obtaining a well matched result" (NERC reliability guideline). If you have P,Q and V (measured values) for the initial and final operating points, how you calculate the Xsource in order to get the suitable voltage and reactive power output in the dynamic simulation? If the external grid in too strong, V does not varies.