Disclosed herein is a rotor for a wound-rotor motor. The rotor for a wound-rotor motor includes: a rotor core including a hollow formed in a central portion thereof and coupled to a shaft; a teeth portion radially formed on an outer side surface of the rotor; and a pole shoe formed to extend from an end portion of the teeth portion in one direction and including a part of a cross section of an outer side surface formed in an arc shape of a first imaginary circle (C1) having a first radius (r1) which is a distance from a central point (CP1) of the hollow to an outermost position (P1) thereof.

This present invention provides a novel DC dynamo which is characterized by making the magnetic lines of flux pass through an air gap between the rotator and the stator in the same direction, thus the most of armature coils can always receive the electromotive force of the same polarity in the same direction. Therefore, bidirectional energy conversion between the mechanical energy and the electrical energy of the armature coils in series can still proceed in the absence of commutators and induced the armature to generate sufficient electromotive force to conveniently regulate suitable terminal voltages and the ratios of the rotating speed and the moving speed thereof.

Various embodiments of a system and associated method for an electrically efficient motor including two parallel shafts, one or more rotors including a plurality of alternating permanent magnets mounted on each shaft, and an electromagnet operable for switching polarities in order to keep the one or more rotors, and consequently the two parallel shafts, in rotational motion.

Various embodiments of a system and associated method for an electrically efficient motor including two parallel shafts, one or more rotors including a plurality of alternating permanent magnets mounted on each shaft, and an electromagnet operable for switching polarities in order to keep the one or more rotors, and consequently the two parallel shafts, in rotational motion.

A method is described for operating an electric media-flow machine for a compressor and/or a turbine, especially for an exhaust-gas turbocharger of an internal combustion engine, having a shaft rotationally mounted in a housing that has an inlet and an outlet for a medium to be conveyed, a rotor being disposed in rotatably fixed manner on the shaft, having a stator that is fixed in the housing and has at least one polyphase drive winding as well as a plurality of stator teeth projecting radially to the inside, having a covering cap that covers the rotor upstream and to which an inner sleeve is joined surrounding the rotor circumferentially. An outer sleeve is disposed coaxially relative to the inner sleeve, the inner sleeve and the outer sleeve being fixed in the housing, and the stator teeth extending through the outer sleeve at least up to the inner sleeve.

A method is described for operating an electric media-flow machine for a compressor and/or a turbine, especially for an exhaust-gas turbocharger of an internal combustion engine, having a shaft rotationally mounted in a housing that has an inlet and an outlet for a medium to be conveyed, a rotor being disposed in rotatably fixed manner on the shaft, having a stator that is fixed in the housing and has at least one polyphase drive winding as well as a plurality of stator teeth projecting radially to the inside, having a covering cap that covers the rotor upstream and to which an inner sleeve is joined surrounding the rotor circumferentially. An outer sleeve is disposed coaxially relative to the inner sleeve, the inner sleeve and the outer sleeve being fixed in the housing, and the stator teeth extending through the outer sleeve at least up to the inner sleeve.

An improved flywheel system for storing energy and providing the stored energy includes a rotor on a centrally located shaft. The shaft is positioned through support bearings. A magnetic off-loader provides a magnetic force to move the shaft axially in regard to the bearings. A feedback control system, provided to reduce bearing loads on the bearing, comprises a sensor mounted in a bearing housing positioned to measure the distance of a gap between a top end of the shaft and a lower surface of the sensor. In response to changes in the distance the sensor sends an electrical signal to a controller which in turn provides variable electric current to the magnetic off-loader which then provides a magnetic lifting force to the rotor on the shaft to minimize bearing load.

An improved flywheel system for storing energy and providing the stored energy includes a rotor on a centrally located shaft. The shaft is positioned through support bearings. A magnetic off-loader provides a magnetic force to move the shaft axially in regard to the bearings. A feedback control system, provided to reduce bearing loads on the bearing, comprises a sensor mounted in a bearing housing positioned to measure the distance of a gap between a top end of the shaft and a lower surface of the sensor. In response to changes in the distance the sensor sends an electrical signal to a controller which in turn provides variable electric current to the magnetic off-loader which then provides a magnetic lifting force to the rotor on the shaft to minimize bearing load.

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.