Cavity Structure for Permanently Excited Electric Machines With Embedded Magnets

A rotor for a permanently excited electric machine, the rotor comprising:

• at least two rotor poles that are arranged adjacent to one another in a circumferential direction;
• a rotor iron core comprising for each rotor pole, at least one hollow space that extends in an axial manner through the rotor iron core, wherein respective webs that extend in the circumferential direction are formed in a radial direction between the at least one hollow space and an outer face of the rotor iron core;
• and
• a permanent magnet arrangement that is embedded in the rotor iron core so as to generate an air gap magnetic flux density in an air gap of the electric machine, the air gap being adjacent to the outer face of the rotor iron core, wherein:
• the permanent magnet arrangement comprises, for each rotor pole, at least one permanent magnet that is arranged in a respective hollow space,
• so as to influence a progression of an air gap magnetic flux density, magnetic flux blocking sections and magnetic flux conducting sections are arranged in an alternating manner along the circumferential direction in at least one web of each rotor pole,
• the magnetic flux conducting sections are formed by rotor iron core regions, and
• the magnetic flux blocking sections are configured so as to conduct a magnetic flux of an associated permanent magnet within a respective adjacent magnetic flux conducting section and comprise different geometries along the circumferential direction starting from a rotor pole middle to rotor pole edges.

A permanently excited machine comprising:

• a stator;
• and
• a rotor that is mounted in such a manner as to be rotatable with respect to the stator, wherein:
• an air gap is formed between the rotor and the stator, and
• the rotor comprises:
• at least two rotor poles that are arranged adjacent to one another in a circumferential direction;
• a rotor iron core comprising for each rotor pole, at least one hollow space that extends in an axial manner through the rotor iron core, wherein respective webs that extend in the circumferential direction are formed in a radial direction between the at least one hollow space and an outer face of the rotor iron core;
• and
• a permanent magnet arrangement that is embedded in the rotor iron core so as to generate an air gap magnetic flux density in an air gap of the electric machine, the air gap being adjacent to the outer face of the rotor iron core, wherein:
• the permanent magnet arrangement comprises, for each rotor pole, at least one permanent magnet that is arranged in a respective hollow space,
• so as to influence a progression of an air gap magnetic flux density, magnetic flux blocking sections and magnetic flux conducting sections are arranged in an alternating manner along the circumferential direction in at least one web of each rotor pole,
• the magnetic flux conducting sections are formed by rotor iron core regions, and
• the magnetic flux blocking sections are configured so as to conduct a magnetic flux of an associated permanent magnet within a respective adjacent magnetic flux conducting section and comprise different geometries along the circumferential direction starting from a rotor pole middle to rotor pole edges.