The axial magnetic field occurs in the end-region of large turbo-generators is known to induce hot points or voltages between laminations, that may cause insulation breakdown and thus stator faults.
It is important to dispose of simple methods for estimating the axial flux rapidly with regard to the operating point of the machine.
The authors provide a practical model of the axial magnetic field based on a simplified vector diagram. The parameters required to build the vector composition of the flux densities are assessed with a limited number of finite element method simulations of the whole end-region of the machine. These simulations were validated by an experimental test on a real turbo-generator. Then the axial flux density was simply estimated for various operating points.
The originality of the paper concerns the practical model of the axial magnetic field based on a simplified vector diagram.
