An excitation system for a brushless generator having a main generator portion including a field winding disposed on a rotor and an armature winding disposed in a stator includes an exciter portion having a set of polyphase exciter field windings disposed in the stator and an armature winding disposed...http://www.google.ca/patents/US5068590?utm_source=gb-gplus-sharePatent US5068590 - Brushless generator having AC excitation in generating and starting modes
