Permanent Magnet Type Electric Rotary Machine And Compressor Using The Same

A permanent magnet type electric rotary machine comprising:

• a stator including a stator core having teeth and slots between adjacent teeth, and a concentrated winding as an armature winding installed in each of the slots so as to surround each of the teeth;
• and
• a rotor provided with permanent magnets as magnet poles installed in a plurality of permanent magnet insertion holes provided in a rotor core respectively, the rotor being rotatably supported inside the stator keeping a gap between the rotor core and the stator core by a rotating shaft,
• wherein defining that a magnetic flux axis of each of the permanent magnets is a d-axis, and an axis 90° apart in electrical angle from the d-axis is a q-axis, respective install positions of the permanent magnets in the rotor core are set between adjacent q-axes,
• wherein a pole core portion between each of the permanent magnets and an outer surface of the rotor core is provided with a plurality of pole slits,
• wherein the region of the pole core portion is defined by concave portions provided on q-axes to be interpolars on both sides of the pole core portion, and thereby configured that a gap (g2) between the outer surface on the q-axis of the rotor core and an inner surface of the stator core is larger than a gap (g1) between the outer surface on the d-axis of the pole core portion and the inner surface of the stator, so that magnetic fluxes from the permanent magnet pass through the pole core portion concentrately,
• wherein the outer surface like an arc-shape of the pole core portion is formed asymmetrically with respect to the d-axis by making circumferential-direction lengths of the concave portions on both sides of the pole core portion different from each other;
• and
• wherein each of the concave portion is formed in the axial direction of the rotor core, with a stepped w-shape skew structure in view of the circumferential direction of the rotor core, so that the pole core portion has a stepped w-shape skew structure.

A permanent magnet type electric rotary machine comprising:

• a stator including a stator core having teeth and slots between adjacent teeth, and a concentrated winding as an armature winding installed in each of the slots so as to surround each of the teeth;
• and
• a rotor provided with permanent magnets as magnet poles installed in a plurality of permanent magnet insertion holes provided in a rotor core respectively, the rotor being rotatably supported inside the stator keeping a gap between the rotor core and the stator core by a rotating shaft,
• wherein defining that a magnetic flux axis of each of the permanent magnets is a d-axis, and an axis 90° apart in electrical angle from the d-axis is a q-axis, respective install positions of the permanent magnets in the rotor core are set between adjacent q-axes,
• wherein a pole core portion between each of the permanent magnets and an outer surface of the rotor core is provided with a plurality of pole slits,
• wherein the region of the pole core portion is defined by concave portions provided on q-axes to be interpolars on both sides of the pole core portion, and thereby configured that a gap (g2) between the outer surface on the q-axis of the rotor core and an inner surface of the stator core is larger than a gap (g1) between the outer surface on the d-axis of the pole core portion and the inner surface of the stator, so that magnetic fluxes from the permanent magnet pass through the pole core portion concentrately,
• wherein the outer surface like an arc-shape of the pole core portion is formed asymmetrically with respect to the d-axis by making circumferential-direction lengths of the concave portions on both sides of the pole core portion different from each other;
• and
• wherein each of the concave portion is formed with a stepped zigzag skew structure in the axial direction of the rotor core, so that the pole core portion has a stepped zigzag skew structure, and both end sides in axial direction of the zigzag skew structure are formed in the same shape.