On equivalent circuit modeling for synchronous machines

This paper presents alternative equivalent circuits for modeling the steady state frequency response (SSFR) data measured for turboalternator synchronous machines. These models provide direct representation of the frequency-dependent skin-effect properties of the dampers and rotor iron. The parameters are determined by matching the measured data to the model frequency response using standard optimization methods. The accuracy of matching is comparable to that of conventional third-order d-q models but the required number of parameters is reduced.