A brushless winding field rotational electric machine includes: a stator, held to a case, including an alternating-current coil configured to generate a rotation magnetic field by alternating current; a field core, held to the case, including a field coil to be excited by direct current; and a rotor on an outer periphery of a rotation member and rotatably held about a rotational axis relative to the stator and field coil. The field coil includes a plurality of coil winding layers stacked in a radial direction of the rotational axis. A cross-sectional area along an axial direction of the rotational axis, of a coil winding layer closest to the rotational axis in the radial direction of the rotational axis is smaller than a cross-sectional area along the axial direction of the rotational axis, of a coil winding layer farthest from the rotational axis in the radial direction of the rotational axis.

A rotary electric machine, e.g., a cycloidal reluctance motor, includes a stator having stator teeth connected to a cylindrical stator core, and a rotor having a cylindrical rotor core. The stator core and/or rotor core are constructed of grain-oriented, spirally-wound ferrous material having a circular or annular grain orientation. The stator teeth may be constructed of grain-oriented steel having a linear grain orientation. Notches may be spaced around an inner circumferential surface of the stator core, with each stator tooth engaged with a respective notch. The rotor may be eccentrically positioned radially within the stator. The rotor core may define notches spaced around its outer circumferential surface, with salient rotor projections engaged with a respective rotor notch. The machine in such an embodiment may be a switched reluctance rotor. An electrical system using the machine and a method of manufacturing the machine are also disclosed.

Prioritizing one-way rotation and one-way torque in particular, a change is induced in the partial shape of a magnetic poles on the rotor of a reluctance motor in the direction of forward movement, or magnetic resistance is increased, the torque generation range of each phase is expanded, and the increase/decrease time of an electric current is ensured to reduce the noise. With the relative increase in copper losses due to this drive method, and harmful effects from the problem of an overvoltage generated in the full-pitch windings are reduced by a drive method in which the overvoltage is cancelled out.

The disclosure relates to a brushless and magnet-free synchronous electrical machine, wherein it comprises a stator (20) comprising a ring (22), a winding (28) and a tooth system (24) comprising teeth (26) extending parallel to the axis of rotation from the ring (22), said winding being wound around the tooth system (24), a rotor (10), comprising a first portion (12a) extending in p preferred directions (18a), a second portion (12b) extending in p preferred directions (18b) shifted by p with respect to the preferred directions of the first portion (18a), and an intermediate portion (14) linking the first portion (12a) to the second portion (12b), and a coil (40) for exciting the rotor, fixed with respect to the stator, supplied with a DC electric current, positioned around the intermediate portion (14) of the rotor and configured so as to generate an electric flux in the rotor (10) through magnetic induction.

A rotor is located around an outer periphery of a rotation shaft of a motor and rotates together with the rotation shaft. The rotor includes magnetic steel plates laminated in an axial direction and including a through-hole group passing therethrough in the axial direction. The through-hole group includes through-holes each including, as a central line, an imaginary line extending in the radial direction and having an arcuate shape extending from the central line to both sides and radially outward. The through-holes are arranged in the radial direction. Among the through-holes, a radius of curvature of an arcuate radially inner side surface of the radially innermost through-hole is the smallest, and/or a radius of curvature of an arcuate radially outer side surface of the radially outermost through-hole is the largest.

An electrical sub-assembly comprises a stator having a plurality of coils and a cooling means attached to the stator. The electrical sub-assembly further comprises a plurality of pairs of diodes attached to the cooling means, each pair of diodes being in antiparallel configuration and having three electrical terminals. One of the three electrical terminals is a common terminal shared by both diodes in each pair of diodes. A plurality of busbars electrically connect each of the diodes to at least one of the plurality of coils via one or more of the electrical terminals. In use, the cooling means is configured to simultaneously cool the stator and the plurality of diodes. The electrical sub-assembly may have particular application as a part of a switched reluctance machine.

A hybrid induction motor includes a fixed stator, an independently rotating outer rotor, and an inner rotor fixed to a motor shaft. The outer rotor is designed to have a low moment of inertia and includes angularly spaced apart first bars and permanent magnets on an inner surface of the outer rotor. The inner rotor includes angularly spaced apart second bars and interior flux barriers aligned with the second bars. The outer rotor is initially accelerated by cooperation of a rotating stator magnetic field with the first bars. As the outer rotor accelerates towards synchronous RPM, a rotating magnetic field of the permanent magnets cooperate with the second bars of the inner rotor to accelerate the inner rotor. At near synchronous speed the rotating stator magnetic field reaches through the outer rotor and into the inner rotor coupling the two rotors for efficient permanent magnet operation.

A rotary electrical machine includes a stator, a field core, a rotor, and first and second air gaps. The stator includes an AC coil that generates a rotating magnetic field with an alternating current. The field core includes a field coil excited by a direct current. The rotor is disposed on an outer circumference of a starting apparatus and held rotatably about a rotational axis relative to the stator and the field coil. The first air gap is formed between the stator and the rotor, and allows a magnetic flux to flow therebetween. The second air gap is formed between the field core and the rotor, and allows a magnetic flux to flow therebetween. The second air gap defines an interval extending along a direction that intersects an axial direction of the rotational axis on one end surface of the rotor in the axial direction of the rotational axis.

Various embodiments are described herein for switched reluctance machine configurations. In at least one embodiment, a switched reluctance machine configured according to the teachings herein includes an axially extending shaft, an axially extending rotor mounted to the shaft, the rotor having a plurality of salient rotor poles, an axially extending stator disposed coaxially and concentrically with the rotor, the stator having a plurality of salient stator poles protruding radially from the stator towards the rotor poles, a plurality of stator teeth and tooth-tips, and a plurality of electrical coils wound about the stator poles to define a plurality of phases of the switched reluctance machine, where a number of stator poles can be determined according to the following equation and at least one constraint condition: $N_s=\frac{N_t\times \mathrm{LCM}\left(N_s,N_r\right)}{N_r\times N_{\mathrm{ph}}\times S_1\times S_2}.$

Exchangeable stator components are selected and exchangeable rotor components are selected to transform a motor from one motor class to another motor class. [0006] A motor comprises at least two stator rings, at least two outer rotor rings, a first input, and a second input. The first input comprises an exchangeable stator component selected from a stator component group consisting of a stator spacer ring and an axially magnetized stator magnet ring, the axially magnetized stator magnet ring comprising a solid axially magnetized ring magnet. The second input comprises an exchangeable rotor component selected from a rotor component group consisting of a rotor spacer ring and an axially magnetized rotor magnet ring. The first input and the second input determine a motor class for the motor, the exchangeable stator component being exchangeable for a different exchangeable stator component from the stator component group to manufacture another motor having a different motor class, the exchangeable rotor component being exchangeable for a different exchangeable rotor component from the rotor component group to manufacture another motor having another different motor class.