Cooling system for an electrical machine with center rotor cooling ducts

摘要

An electrical machine includes a stator (14) having a radially inwardly directed duct (30) adjacent the center of the machine for flowing cooling medium into the gap (18) between the stator and rotor. The rotor includes radial ducts (34) or diagonal ducts having scoops (36) for directing flow generally radially inwardly to cool the field windings in the center of the machine. The cooling medium flows either into subslots (40) for radial or diagonal outward flow through outlet ducts for return to the gap.