Estimation of the Natural Frequencies of Turbogenerator Busbars

The objective of this study is to give an understanding of how the natural frequencies and modes of the end-winding components in high-power turbogenerators can be determined. Results from an analysis of various methods are presented, and the main factors that hamper the computation of the natural frequencies with accuracy required for practical purposes are identified. Finite-element 3D modeling was performed to determine the natural frequencies of the outputs and a part of the stator bus ring. It is shown that the calculated frequencies are strongly dependent on the accuracy of modeling the boundary conditions. To improve the accuracy of numerical modeling, it is necessary to use bench and full-scale test data. © 2016, Springer Science+Business Media New York.