Detailed off-line parameter identification of synchronous generator based on frequency response tests

Abstract

This work presents a general methodology, based on standstill frequency response tests. Once the circuit topology is chosen, it allows a systematic calculation of the circuit parameters for a salient pole synchronous generator. The order of the circuit considered can be whatever, even a customized circuit topology, since the methodology does not rely on a specific formulation. The transfer function coefficients are expressed as a function of the circuit parameters by using the symbolic Matlab toolbox. From tests, the coefficients of the transfer function are fitted in both axes. Then the coefficients have to match with the symbolic transfer function previously obtained in order to calculate the circuit parameters. If the dynamic behavior obtained with the fitted parameters is not accurate enough, the circuit order is increased until attaining an accurate solution. This methodology results in a useful educational tool for machine characterization. Nowadays many methods are found in the technical literature to calculate such parameters, although most of them computationally demanding.