Rotating electric machine with rotor cooling slots

A rotor of a rotating electric machine, comprising:

• a cylindrical rotor core;
• a plurality of coil slots provided on an outer periphery of the rotor core along a rotor axis direction;
• rotor coils disposed in the coil slots by laminating a plurality of field conductors through an insulation material;
• a rotor wedge disposed at an opening end portion of the coil slots so as to support the rotor coils;
• a coil ventilation duct formed in the coil slots so as to pass through the rotor coils, the rotor wedge and the insulation material;
• and
• sub-slots provided at bottom portions of the coil slots so as to be communicated with rotor core ends and the coil ventilation ducts,
• wherein the coil slots, the sub-slots and the coil ventilation duct constitute a cooling gas channel for distributing a cooling gas to thereby cool the rotor coils, and a depth in a diameter direction of each sub-slot from the rotor coil end to a nearest coil ventilation duct is larger than a depth of the sub-slot at a portion near a center of the rotor core, and the sub-slots are provided on a rotor inner circumferential side in the coil slots along the axial direction of the rotor core.