Hybrid excitation rotating electrical machine

A hybrid excitation rotating electrical machine, comprising:

• a rotor having a shaft extended on at least one side in an axial direction, and first and second cores that are separated in the axial direction with a gap between the cores, wherein first magnetic poles that are excited by a permanent magnet and second magnetic poles that are not excited by the permanent magnet are alternately arranged in a circumferential direction in each of the first and second cores, the first magnetic poles of the first core have a different polarity from that of the first magnetic poles of the second core, and the first magnetic poles of one of the first and second cores are placed so as to face the second magnetic poles of the other of the first and second cores in the axial direction with the gap between the magnetic poles;
• a stator that is placed radially outward of the rotor, and that generates a rotating magnetic field rotating the rotor;
• an exciting coil that is placed in the gap, and that excites the second magnetic poles;
• and
• a third core that is placed radially inward of the first core, the second core, and the exciting coil, and that is made of a material having smaller iron loss than the shaft wherein:
• the shaft is formed in a hollow shape,
• each of the first core and the second core is placed radially outward of the shaft and is supported by the shaft, and
• the third core is placed radially inward of the shaft and is supported by the shaft.