Methods and systems are provided for operating an electric motor including multiple rotor and stator sections. In one example, a system may include the multiple rotor sections configured to be mechanically coupled and decoupled from each other concurrently with multiple stator sections configured to be electrically coupled and decoupled from each other, within certain regimes of operation of the electric motor.

Methods and systems are provided for operating an electric motor including multiple rotor and stator sections. In one example, a system may include the multiple rotor sections configured to be mechanically coupled and decoupled from each other concurrently with multiple stator sections configured to be electrically coupled and decoupled from each other, within certain regimes of operation of the electric motor.

Disclosed are various embodiments for an electric machine where the stator is a coil assembly and the rotor is a magnetic toroidal cylindrical tunnel or where the rotor is a coil assembly and the stator is a magnetic toroidal cylindrical tunnel.

Disclosed are various embodiments for an electric machine where the stator is a coil assembly and the rotor is a magnetic toroidal cylindrical tunnel or where the rotor is a coil assembly and the stator is a magnetic toroidal cylindrical tunnel.

A motor (1) has a pair of journal supports (2), between which is journalled a rotor (3) on a shaft (4). The rotor has a disc (5) fast with the shaft and at right angles to it, whereby it rotates without wobble. At the circumference of the disc, a plurality of short, circular cylindrical permanent magnets (6) are provided at the same radial distance (7) from the shaft to their polar axes, tangential to the disc at their mid-point, with their polar axes in the central plane of the disc and the midpoints of the axes on a circular path (9) of radius (7), and equally spaced around the disc with an angular pitch (10) equal to double their polar length (11). A stator (12) carried by the supports on rods (14). It included two formers (15,16).

A dual-rotor machine comprising a dual rotor support structure rotatably connected to a frame. A stationary stator is disposed between the rotors and is fixed to the frame. An inner rotor and outer rotor, each comprising a permanent magnet Halbach array, are coaxially disposed with the stator and are rotable about the stator. In this configuration, the inner rotor channels its magnetic flux to its outside, while the outer rotor channels its magnetic flux to its inside. The magnetic flux density at the stator for the dual-rotor machine can be as high as 2 Tesla or higher for high-grade neodymium-iron-boron permanent magnet material, and the stored magnetic energy for conversion to mechanical or electrical energy available to the stator may be at least 0.5 kJ/m. The rotor Halbach arrays may comprise monolithic permanent magnets with continuously variable magnetic field direction.

A dual-rotor machine comprising a dual rotor support structure rotatably connected to a frame. A stationary stator is disposed between the rotors and is fixed to the frame. An inner rotor and outer rotor, each comprising a permanent magnet Halbach array, are coaxially disposed with the stator and are rotable about the stator. In this configuration, the inner rotor channels its magnetic flux to its outside, while the outer rotor channels its magnetic flux to its inside. The magnetic flux density at the stator for the dual-rotor machine can be as high as 2 Tesla or higher for high-grade neodymium-iron-boron permanent magnet material, and the stored magnetic energy for conversion to mechanical or electrical energy available to the stator may be at least 0.5 kJ/m. The rotor Halbach arrays may comprise monolithic permanent magnets with continuously variable magnetic field direction.

A motor includes: a first portion that includes a plurality of permanent magnets; and a second portion that includes a plurality of coils, wherein the first portion or the second portion is configured to be rotatable around a rotation axis, wherein the plurality of permanent magnets are circumferentially arranged about the rotation axis, and wherein the plurality of coils are arranged so as to face the plurality of permanent magnets in a direction along the rotation axis, and the motor further includes: a control unit that controls a rotational speed and an attitude of the rotating first portion or the rotating second portion by controlling currents that are applied to the plurality of coils.

A motor system comprises a motor comprising: a stator with a plurality of subwindings each having a plurality of phase connections for receiving phase voltages, wherein each of the subwindings is electrically insulated from each of the other subwindings; a rotor comprising a plurality of permanent magnets or energisable electromagnets; a controller comprising a plurality of control parts, each control part associated with a respective subwinding, each control part being configured to monitor phase voltages of the associated subwinding, between phase connections. The system further comprises a controller configured to: obtain, from each control part, at set discrete time intervals, a plurality of back measured electromotive force, EMF, readings for each of the respective subwindings; using the plurality of measured back EMF readings and an a priori knowledge of the motor's construction to estimate a commutation event timing.

A motor system comprises a motor comprising: a stator with a plurality of subwindings each having a plurality of phase connections for receiving phase voltages, wherein each of the subwindings is electrically insulated from each of the other subwindings; a rotor comprising a plurality of permanent magnets or energisable electromagnets; a controller comprising a plurality of control parts, each control part associated with a respective subwinding, each control part being configured to monitor phase voltages of the associated subwinding, between phase connections. The system further comprises a controller configured to: obtain, from each control part, at set discrete time intervals, a plurality of back measured electromotive force, EMF, readings for each of the respective subwindings; using the plurality of measured back EMF readings and an a priori knowledge of the motor's construction to estimate a commutation event timing.