Influence of Magnetic Pole Ovality on the Unbalanced Magnetic Pull of a 1000 MW Hydro-generator Unit Installed with High Precision

Rotor deformation is one of the key problems of large turbine generators. Previous studies mainly calculated the unbalanced magnetic pull (UMP) of turbine generators. Giant hydroelectric generators are huge in size and extremely complex in structure, so there are few relevant UMP analyses about them up to now. This paper uses a two-dimensional transient finite element method to calculate the transient magnetic field and reveal the effect of rotor deformation on the UMP of a 1000 MW hydro-generator in the time and frequency domains. Theoretical calculations are in good agreement with field measurements. The results of this investigation can provide scientifically valuable guidance for the manufacture and installation of structurally complex giant hydraulic turbine units.