Wave-resistance analysis of turbo-generator rotors with subtransient asymmetry or symmetry

This paper describes a method by means of which the wave resistance and, approximately, the negative-sequence losses of anisotropic turbo-rotors can be determined from standstill measurements on the test bed and divided into the components for the pole and field winding regions. For turbo-rotors with incomplete damper cage a marked difference can be demonstrated between the specific surface resistances and losses of these two peripheral zones, which may be attributed entirely to the pole iron. When the damper cage is complete, this iron is largely relieved. Thus the pronounced influence of the damper Structure on the rotor wave resistance, as well as on the negative-sequence resistance and losses of solid-rotor synchronous machines is proved direct and confirmed quantitatively.