Abstract: An electric machine includes a stator and a rotor. The rotor includes stacked laminations forming a rotor core. The rotor rotates relative to the stator about a central axis. The rotor core has an outer diameter. Each lamination includes a plurality of magnet slots. Each magnet slot includes a ferrite permanent magnet located therein, adjacent pairs of the ferrite permanent magnets defining a number of poles. Each of the laminations includes a plurality of non-circular rotor bar apertures spaced about the central axis of the rotor and disposed adjacent to and radially inward of the rotor outer diameter. A non-cylindrical rotor bar is disposed in each respective of the plurality of rotor bar apertures. The rotor bars are formed of a conductive material, wherein at least some of the plurality of rotor bars collectively form a rotor bar cage.

Abstract: An electric machine includes a stator defining a rotor chamber. A rotor is disposed within the chamber and is configured to rotate about a central axis. The rotor includes a plurality of stacked laminations to form a rotor core. The rotor core has an outer diameter and each of the laminations includes a plurality of magnet slots that are radially spaced apart from the outer diameter and angled inwardly with one end of each magnet slot adjacent to the outer diameter. Each magnet slot has a permanent magnet disposed therein, adjacent pairs of the ferrite permanent magnets defining poles for the rotor. Each magnet slot has two opposite ends that define inner and outer magnet free areas. The outer magnet free areas are adjacent the rotor outer diameter and the inner magnet free areas are radially inwardly positioned. Each outer magnet free area is provided with conductive material.

Abstract: An electric machine includes a stator and a rotor. The rotor includes stacked laminations forming a rotor core. The rotor rotates relative to the stator about a central axis. The rotor core has an outer diameter. Each lamination includes a plurality of magnet slots. Each magnet slot includes a ferrite permanent magnet located therein, adjacent pairs of the ferrite permanent magnets defining a number of poles. Each of the laminations includes a plurality of non-circular rotor bar apertures spaced about the central axis of the rotor and disposed adjacent to and radially inward of the rotor outer diameter. A non-cylindrical rotor bar is disposed in each respective of the plurality of rotor bar apertures. The rotor bars are formed of a conductive material, wherein at least some of the plurality of rotor bars collectively form a rotor bar cage.

Abstract: A magnetic coupling for transferring rotational motion from a prime mover to a load includes reference marks calibrated to indicate torque applied to the coupling during operation. A light source providing intermittent light flashes permits a user to visibly discern the relative rotational position of the reference marks to one another, and thereby determine the torque applied to the coupling.

Abstract: Redundant winding connections for multiphase electric machines are disclosed. According to one aspect, a multiphase machine having redundant winding connections includes: a first set of N coils operating as a first winding group, wherein each coil in the first winding group operates at a different phase from the other coils in the first winding group and wherein N is an integer greater than three; a second set of N coils separate from the first set and operating as a second winding group, wherein each coil in the second winding group operates at a different phase from the other coils in the second winding group and wherein the failure of one of the coils in the first winding group does not affect the function of the second winding group.

Abstract: A magnetic coupling for transferring rotational motion from a prime mover to a load includes reference marks calibrated to indicate torque applied to the coupling during operation. A light source providing intermittent light flashes permits a user to visibly discern the relative rotational position of the reference marks to one another, and thereby determine the torque applied to the coupling.

Abstract: Redundant winding connections for multiphase electric machines are disclosed. According to one aspect, a multiphase machine having redundant winding connections includes: a first set of N coils operating as a first winding group, wherein each coil in the first winding group operates at a different phase from the other coils in the first winding group and wherein N is an integer greater than three; a second set of N coils separate from the first set and operating as a second winding group, wherein each coil in the second winding group operates at a different phase from the other coils in the second winding group and wherein the failure of one of the coils in the first winding group does not affect the function of the second winding group.