Patent ID: 9705388
Date: 2017-07-11
CPC Classifications: H02K

Claim:
1. An electrical machine comprising: a stator; a rotor core disposed within the stator; the rotor core comprising a plurality of generally like laminations stacked end to end to form a contiguous rotor core, the rotor core being rotatable relative to the stator about a center axis, the rotor core having an outer diameter (D a plurality of magnet slots being spaced radially inward of the rotor outer diameter with a first end of each of the magnet slots being adjacent to the rotor outer diameter and the magnet slots extending generally inward from their first ends toward the rotor center axis, the magnet slots having permanent magnets disposed therein, the permanent magnets disposed in the magnet slots defining a number of poles (P) for the machine, a pole pitch (pp) for the machine wherein the pole pitch (pp)=(π×D a plurality of rotor bar slots spaced about the rotor core center axis, each of the rotor bar slots being radially inward of the rotor outer diameter with an end of the rotor bar slot being adjacent to the rotor outer diameter, the plurality of rotor bar slots having an asymmetric angular spacing about the rotor core; wherein the rotor bar slots disposed in the saturation boundary area are spaced from an adjacent magnet slot by a distance that is at least four percent of the pole pitch (“pp”); a conductive material disposed in the rotor bar slots; and end members disposed on axial opposite ends of the rotor core, the end members being in electrical contact with the conductive material; wherein the rotor bar slots disposed outside of the saturation boundary are spaced from an adjacent magnet slot by a distance that is at least four percent of the pole pitch.