A strategy to reduce the vibrations generated by the harmonics of armature reaction in hydro generators

A strategy to eliminate the vibrations generated by the harmonics of armature reaction in the stator of hydrogenerators is described in this paper. It consists of the verification and optimization of the stator winding configuration, considering that the three phase currents in the windings are sinusoidal and balanced, and that the induction is proportional to the magnetomotive force. Calculation of the coefficients dependent on winding configuration leads to the formulation of the vibration causing forces. Furthermore, this approach permits the determination of the relative amplitude of the radial efforts caused by the armature reaction on the magnetic circuit. The standard solutions, such as chording, are insufficient to solve all the different problems. A new method based on the rearrangement of the conductors distribution to neutralize the harmonics that cause the deformation of the space wave is experimented upon.