Generator end windings forces and natural frequency analysis

Abstract

The end windings of hydro-generators are subject to electromagnetic forces during their operations. These forces will cause the winding to vibrate and deflect, which may lead to the excitation of the natural frequencies. In order to study in detail this phenomenon, a quasi-3D electromagnetic model, which computes the forces on the conductor bars, is coupled with 3D mechanical model to calculate the displacements using the computed electromagnetic forces. Numerical results during fault conditions of a 110 MVA synchronous generator are presented.