Patent ID: 8933606
Filing Date: 2015-01-13
Classification: H02K

Abstract:
1. An interior permanent magnet machine comprising: a rotor having a center and a plurality of slots, the rotor being configured to magnetically interact with a stator; a first and a second pole defined by first and second pole axes in the rotor, respectively; wherein the plurality of slots includes first, second, third and fourth slots, the first and second slots being disposed in the first pole and the third and fourth slots being disposed in the second pole; a first barrier defined by the first, second, third and fourth slots; wherein the first and second slots are symmetric relative to the first pole axis and the third and fourth slots are symmetric relative to the second pole axis; a first angle defined between respective centerlines of the first and second slots, and a second angle defined between respective centerlines of the third and fourth slots; and wherein the first angle is sufficiently different from the second angle to minimize torque ripple.