Stator Frame Deformation Problem in Large Diameter Hydro-Generators

The hydrogenerators which have been delivered to Peace Canyon Power Station of B.C. Hydro and Power Authority are large diameter machines. In large diameter hydrogenerators the relative displacement between the rotor and stator tends to increase, and in the worst case the rotor may touch the stator. The above hydrogenerators have experienced some problems due to the deformation of the stator frame. The outline of problems and investigations performed to determine the relationship between stator deformation and split phase current is presented.