Modal Parameter Extraction of a Turboset From High Speed Balance Data

Abstract

Turbosets used in power generation industry are frequently placed on flexible foundations, which significantly influence the overall dynamics. Establishment of structural models that capture the rotor and foundation effects reliably using finite element modeling or modal analysis is difficult because of model complexity and/or costs involved. This paper presents a method to extract modal parameter information of a turboset using frequency response function data recorded during high speed balancing. The main advantage of the present method over the others is the low cost and small effort involved, so that it is of practical use in an industrial setting. A real life example dealing with parameter extraction for a large generator rotor is presented to demonstrate its implementation.