Analysis of synchronous generator end-winding deformations using 3-D time-harmonic FEM

The 3-D time-harmonic finite element method (FEM) has been used to calculate forces and deformations of synchronous generator end-windings under nominal operational conditions. Analysis of the time-variant magnetic field has been performed using a T, Phi - Phi formulation. A novel method to consider the rotating magnetic field of the rotor in the frequency domain has been developed. The influence of the induced eddy currents in steel front-plates of a machine has been taken into consideration in order to take the exact boundary conditions into account. Under design operating conditions, computed harmonic forces specified by amplitude and phase have been applied to the mechanical model in order to simulate the frequency response of the end-winding system.