Computation of induced voltages and currents in the field winding of wound-field synchronous machines under transient conditions

Computation of the transient behavior of wound-field synchronous generators typically focuses on the stator currents. Appropriate models to compute these currents have been derived. However, the calculation of the transient voltages and currents in the field winding of such machines-as for example required for the design of the components of a brushless exciter (diodes, resistance)-requires this model to be expanded by an additional inductance describing the coupling between the damper and the field winding. Further, the damping effect of the eddy currents of a massive rotor may be considered. In this paper, we investigate the applicability of these models and apply the study to a turbo as well as a hydro generator that are both investigated theoretically and experimentally.