Calculation and Measurement of Frequency Response of Large Turbogenerators in the Presence of Small Distrubances

In this paper is outlined a method for analyzing transient operation of large turbogenerators illustrated by the special case of small disturbances response. This method involves the solution of Maxwell equations in the massive rotor materials. An approximate solution is provided by simple functions which permit completing energy calculations yielding the equivalent circuits and transfer functions. This method was applied to a 600 MW turbogenerator on which the same transfer functions were measured using a method which consists of statistically analyzing the alternator´s response to random load changes. Lastly, calculated and test results are compared.