Skip to Content
Find More Like This
Return to Search

Torque ripple reduction in electric machines

United States Patent

9,742,228
August 22, 2017
View the Complete Patent at the US Patent & Trademark Office
An electric machine, such as an Internal Permanent magnet or Synchronous Reluctance machine, having X phases, that includes a stator assembly, having M slots, with a stator core and stator teeth, that is further configured with stator windings to generate a stator magnetic field when excited with alternating currents and extends along a longitudinal axis with an inner surface that defines a cavity; and a rotor assembly, having N poles, disposed within the cavity which is configured to rotate about the longitudinal axis, wherein the rotor assembly includes a shaft, a rotor core located circumferentially around the shaft. The machine is configured such that a value k=M/(X*N) wherein k is a non-integer greater than about 1.3. The electric machine may alternatively, or additionally, include a non-uniformed gap between the exterior surface of the rotor spokes and the interior stator surface of the stator.
Reddy; Patel Bhageerath (Niskayuna, NY), Huh; Kum-Kang (Niskayuna, NY), El-Refaie; Ayman Mohamed Fawzi (Niskayuna, NY), Galioto; Steven Joseph (Waterford, NY)
GENERAL ELECTRIC COMPANY (Niskayuna, NY)
14/ 057,591
20150108868
October 18, 2013
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH & DEVELOPMENT This invention was made with Government support under contract number DE-EE0005573 awarded by U.S. Department of Energy. The Government has certain rights in the invention.