In this paper a methodology for parameter identification of the IEEE standard 421.5 (1992) excitation systems models is presented. The methodology applies parametric identification techniques to the linear dynamics of voltage regulator models. A pseudorandom binary sequence small signal is used in an offline generator test, that allows a reduction in the equipment test time, in comparison with step or frequency response methods. The remaining parameters for the saturation nonlinearities and exciter magnetic saturation are obtained by means of large signal excursion simple tests. The methodology is illustrated applying it to the IEEE ST1A model in simulation, and experimentally to a direct digital auto excited excitation system, represented with the IEEE ST4B model. Simulation and experimental results show the validity of the proposed methodology, with achieved successes percentages of 96% for simulation and 73% for experimentation.