This paper describes an experimental model for the characterization of electromagnetic phenomena that occur in the end regions of large turbo-generators. The study is based on a test bench that contains a stack of steel laminations from a 900 MW turbogenerator stator and two exciting circuits in order to combine a transverse magnetic flux with the in-plane flux. In order to explain the flux penetration within the magnetic sheet stack, accurate experimental measurements are performed. Results are compared with the finite element simulations using code_Carmel3D. In the same time, theoretical and experimental results are analyzed with a view to examining the influence of transverse flux on additional losses.
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