In this paper the numerical simulation of the end-winding deformations in a synchronous machine under symmetrical short circuit conditions is presented. A sequentially coupled numerical simulation between an electromagnetic and a structural mechanical problem has been carried out. Owing to the short-circuit conditions, both problems are to be computed in the time-domain. Analysis of the time-variant magnetic field has been performed using the T, Φ – Φ formulation for the finite element method (FEM). This way, the influence of the induced eddy currents in the clamping-plates and in the housing of the machine on the magnetic field in the end-region of the generator has been taken into the account. In order to reduce the computational time, the non-conforming finite element (FE) mesh approach has been used to solve the electromagnetic problem. In each time-step the Lorentz forces in the end-winding have been calculated and carried over to the structural-mechanical model. These forces have been applied in the centre of the end-winding bars in order to provoke the transient excitation for the mechanical structure. A time-stepping scheme has been applied to calculate end-winding deformations in each time-step.
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