Synchronous machine parameter determination using the sudden short-circuit axis currents

Small salient-pole alternators are being embedded in power systems in growing numbers and parameter sets which accurately reflect the transient response of such machines are in demand. High levels of local saturation and rapidly changing flux densities result in transient currents that are far from the pure exponentials of classical theory so that estimation by curve fitting is difficult. A new approach, which encourages designer intervention, is described and this is seen to be reliable and repeatable, with a good quality of fit, even in the sub-transient region.