A stator of a polyphase motor in which in-phase coils are connected in parallel includes an annular core back, teeth extending radially from the core back and arranged circumferentially, a slot between two adjacent teeth, conducting wires respectively wound around the teeth to define the coils, and first and second connectors to which ends of each of the in-phase coils are connected, respectively. The conducting wire includes one or two jumper wires between each coil and the first connector or the second connector, and at least one jumper wire extends in an identical circumferential direction from the first connector toward the second connector with respect to all the in-phase coils.

A core for an electric machine includes a core body arranged along a rotation axis and a winding. The core body has two or more teeth including a first tooth and a second tooth that are circumferentially spaced from one another about the rotation axis. The winding is to the core body and includes two or more coils connected electrically in series with one another. A first of the coils is seated circumferentially about both the first tooth and the second tooth to define a distributed pole circumferentially spanning both the first tooth and the second tooth. Electric machines and methods of making cores for electric machines are also described.

Unique systems, methods, techniques and apparatuses of exciterless synchronous machines are disclosed. One exemplary embodiment is a fractional slot synchronous machine comprising a rotor including a first pole pair including a first pole including a first plurality of slots having a first center point and arranged on a first outer surface in a slot pattern; a second pole pair including a second pole including a second plurality of slots having a second center point and arranged on a second outer surface in the slot pattern; energy harvest windings arranged in a winding pattern within a portion of the first plurality of slots and arranged in the same winding pattern within a portion of the second plurality of slots, the energy harvest winding being structured to receive a harmonic power from the stator; and a rectifier structured to receive the harmonic power from the energy harvest winding.

A lamination for use in an integrated drive generator is formed from a plurality of plates having a body including a pair of opposed cylindrical surfaces. Non-cylindrical ditches are defined circumferentially intermediate the pair of cylindrical surfaces. A plurality of passages are formed in an outer periphery of the cylindrical surfaces including relatively large holes extending through a slot to the outer periphery. Grooves are formed intermediate the relatively large holes.

A rotor bar fault in a rotor of an electrical machine having a plurality of rotor bars and an end ring configured to short circuit the rotor bars. The method includes the steps of measuring a first temperature at a first end ring location, and measuring a second temperature at a second end ring location, the second end ring location being different from the first end ring location. As broken rotor bars cause a non-uniform temperature distribution in the end ring, the detection of rotor bar faults can be based on monitored temperatures at different end ring locations.

A rotor bar fault in a rotor of an electrical machine having a plurality of rotor bars and an end ring configured to short circuit the rotor bars. The method includes the steps of measuring a first temperature at a first end ring location, and measuring a second temperature at a second end ring location, the second end ring location being different from the first end ring location. As broken rotor bars cause a non-uniform temperature distribution in the end ring, the detection of rotor bar faults can be based on monitored temperatures at different end ring locations.

An electromagnetic actuator for non-continuous rotation (cogging-torque actuator (CTA)) (100) comprises a support structure (116), an output shaft (104) rotatable about and defining an axis of rotation (X), a permanent magnet rotor (106) comprising at least two magnetic poles (108a, 108b) attached to the output shaft (104), and a stator device (110) comprising a ferromagnetic pole body (112) attached to the support structure (116) and surrounding the at least two magnetic poles (108a, 108b). The ferromagnetic pole body (112) can have at least four ferromagnetic stator poles (112a-d) each wrapped in a conductive wire (114a-d) to define a stator coil. The at least four ferromagnetic stator poles (112a-d) are sized, and spaced radially from each other, so as to define a maximum cogging torque of the electromagnetic actuator (100). The CTA (100) can operate as an actuator, an elastic spring, a clutch, and/or a load support device.

An electromagnetic actuator for non-continuous rotation (cogging-torque actuator (CTA)) (100) comprises a support structure (116), an output shaft (104) rotatable about and defining an axis of rotation (X), a permanent magnet rotor (106) comprising at least two magnetic poles (108a, 108b) attached to the output shaft (104), and a stator device (110) comprising a ferromagnetic pole body (112) attached to the support structure (116) and surrounding the at least two magnetic poles (108a, 108b). The ferromagnetic pole body (112) can have at least four ferromagnetic stator poles (112a-d) each wrapped in a conductive wire (114a-d) to define a stator coil. The at least four ferromagnetic stator poles (112a-d) are sized, and spaced radially from each other, so as to define a maximum cogging torque of the electromagnetic actuator (100). The CTA (100) can operate as an actuator, an elastic spring, a clutch, and/or a load support device.

There is provided an electric motor comprising a rotor, a stator and a motor controller. The stator comprises a substantially cylindrical body, a plurality of teeth extending from the substantially cylindrical body in a radial direction, one or more first sets of electrical windings that are wound around said teeth and configured to drive the rotor, and one or more second sets of electrical windings electrically separate from the first set of electrical windings. The second set of electrical windings on the stator are electrically connected to the motor controller such that energy produced by the electric motor during a regenerative mode of operation in use is diverted to the second set of electrical windings on the stator for dissipating the energy produced in the regenerative mode.

A rotor for an electrical machine includes a rotor core having a plurality of circumferentially spaced apart rotor poles. Windings are seated in gaps between circumferentially adjacent pairs of the rotor poles. A wedge secures the windings in each gap. The wedge includes a first member made of a first material and at least one second member made of a second material. The second material has a higher electrical conductivity than the first material. The wedge is configured to supply Q-axis damping. A pair of end plates is connected electrically to the at least one second member at opposing longitudinal ends thereof thereby completing a Q-axis winding circuit for each wedge.