Mixed excitation synchronous generator high in power density

The invention discloses a mixed excitation synchronous generator high in power density. The mixed excitation synchronous generator is divided into a full permanent magnet part and auxiliary electric excitation parts in the axial direction. The mixed excitation synchronous generator is mainly composed of a stator core, a stator permeability sleeve, a stator armature winding, direct current excitation windings, a rotor core pole, a permanent magnet N pole, a permanent magnet S pole, a rotor back yoke and a rotating shaft. The full permanent magnet part is located in the middle of a generator body; the auxiliary electric excitation parts are located on the two sides of the generator body; the rotor core pole and the permanent magnet poles are ranked in a staggered mode; the two annular direct current excitation windings are arranged in a stator and divide the stator core into three sections, and the exterior of the stator core is connected to a magnetic circuit through the permeability sleeve. Magnetic fields ge