Abstract: A magnetic geared rotating machine includes: a stator; a rotor including a plurality of rotor magnets; and a magnetic pole piece rotor including a plurality of magnetic pole pieces each disposed at a radial position between the stator and the rotor. Each of the magnetic pole pieces has a magnetic pole piece end face facing one side in an axial direction. Each of the rotor magnets has a rotor magnet end face facing the one side. At least part of the magnetic pole piece end face is located on the other side in the axial direction relative to the rotor magnet end face, or a finger end face, of each of a plurality of fingers, facing the one side is located on the other side relative to a tooth end face, of a tooth of the stator, facing the one side, the plurality of fingers being configured to hold therebetween a stator magnet disposed on the tooth from both sides in a circumferential direction.

Abstract: A magnetic geared rotating machine, includes: a stator which includes a plurality of stator magnets arranged so as to be aligned in a circumferential direction; a rotor which includes a plurality of rotor magnets arranged so as to be aligned in the circumferential direction, and in which the number of magnetic poles of the plurality of rotor magnets is less than the number of magnetic poles of the plurality of stator magnets; and a magnetic pole piece rotor which includes a plurality of magnetic pole pieces arranged so as to be aligned in the circumferential direction at a radial position between the stator and the rotor.

Abstract: A magnetically geared apparatus comprising a rotor, the rotor comprising: a ring structure; and at least one pole piece mounted relative to the ring structure; wherein at least a portion of the ring structure forms a continuous ring radially inner to the at least one pole piece, wherein the at least one pole piece is received in a pole piece-receiving portion, the pole piece receiving portion being open at a radially outer end.

Abstract: A magnetically geared apparatus comprising a rotor, the rotor comprising: a ring structure; and at least one pole piece mounted relative to the ring structure; wherein at least a portion of the ring structure forms a continuous ring radially inner to the at least one pole piece, wherein the at least one pole piece is received in a pole piece-receiving portion, the pole piece receiving portion being open at a radially outer end.

Abstract: An electrical machine comprising: a first rotor, the first rotor producing a first magnetic field having a first number of pole pairs; a second rotor comprising a plurality of pole pieces, the plurality of pole pieces being arranged to modulate the first magnetic field to produce a second magnetic field having a second number of pole pairs; a stator Comprising one or more windings arranged to produce a third magnetic field arranged to interact with the first number of pole pairs and the second number of pole pairs; wherein the interaction of the third magnetic field with the first number of pole pairs and the second number of pole pairs changes a torque ratio between the first rotor and the second rotor.

Abstract: A magnetically geared apparatus that includes a first rotor and a stator. The stator can include windings and a first plurality of permanent magnets, where the first plurality of permanent magnets are located between the windings and the first rotor. The stator can also include un-magnetized magnetisable material between circumferentially juxtaposed permanent magnets of the first plurality of permanent magnets.

Abstract: A magnetically geared apparatus (400), a pole piece component (420) and a plurality of pole pieces (422) for such apparatus are disclosed. The magnetically geared apparatus (400) comprises the pole piece component (420) and the pole piece component (420) comprises the plurality of pole pieces (422) mounted to a carrier (421), wherein at least one of the pole pieces (500) comprises at least two axially-spaced portions spaced apart by a portion of a higher magnetic reluctance (560) than that of each of the two axially-spaced portions.

Abstract: A system comprises an input member, an output member, a magnetic gear connecting the input member to the output member and control means arranged to control the flow of power from the input member to the output member. The magnetic gear comprises a first set of magnetic poles, a second set of magnetic poles, and a set of pole pieces arranged to modulate the magnetic field between the first set of magnetic poles and the second set of magnetic poles. The control means comprises means for reducing the transmission of torque pulsation and/or oscillation from the input member to the output member.

Abstract: A magnetically geared apparatus comprising a rotor, the rotor comprising: a ring structure; and at least one pole piece mounted relative to the ring structure; wherein at least a portion of the ring structure forms a continuous ring radially inner to the at least one pole piece, wherein the at least one pole piece is received in a pole piece-receiving portion, the pole piece receiving portion being open at a radially outer end.

Abstract: An apparatus and method for holding permanent magnet components, particularly on a rotor of an electrical machine. A magnet carrier (10) comprises a channel (30) suitable for receiving an encircling magnet retainer (20) and a method of manufacturing a magnet assembly (100) comprises providing a magnet carrier (10) comprising a channel (30), mounting a magnet (60) on the magnet carrier (10), and encircling the magnet (60) and magnet carrier (10) with a magnet retainer (20), wherein the magnet retainer (20) passes through the channel (30).

Abstract: An electrical machine is provided comprising a first rotor, wherein the first rotor includes a support structure, a second rotor, a stator and, wherein the first rotor, second rotor and stator are arranged concentrically about a shaft, and at least one of the second rotor and the stator is adapted to accommodate the support structure. An electrical machine is also provided comprising a shaft having an axis, at least one first rotor, at least one second rotor, at least two stators and, wherein the first rotor, second rotor and stators are arranged axially along the shaft and extend from the axis.

Abstract: A magnetic drive system comprising three members, a first and second of which form an input member and an output member each arranged to rotate relative to the third member, wherein two of the members have respective sets of permanent magnets, the two sets having different numbers of magnetic poles, and the other of the members comprises a cylindrical body having a plurality of pole pieces embedded therein, the pole pieces being arranged to modulate the magnetic field acting between the magnets, and wherein one of the pole pieces is of varying radial thickness.

Abstract: Embodiments provide an electrical machine, comprising: first and second moveable elements arranged to interact in a magnetically geared manner via a magnetic field created, at least in part, by a first electrical winding arrangement associated with the first moveable element; and a second electrical winding arrangement which is arranged to interact magnetically with a fundamental harmonic of a magnetic field created by the first electric winding arrangement associated with the first moveable element.

Abstract: Embodiments of the present invention relate to magnetic gears comprising first and second moveable members arranged to interact in a magnetically geared manner via a first electrical winding arrangement arranged to generate, at least in part, a first magnetic flux having a first number of pole-pairs, and one or more pole-pieces arranged to modulate the first magnetic flux to interact with a second magnetic flux having a second number of pole-pairs, wherein the first number of pole-pairs is less than the second number of pole-pairs.

Abstract: A pole piece support comprising a frame having a spaced array of non-magnetic support structures, wherein disposed between at least a pair of adjacent non-magnetic support structures is a magnetic pole piece supported along at least a portion of its body by the adjacent non-magnetic support structures.

Abstract: An electrical machine is provided comprising a first rotor (121), wherein the first rotor includes a support structure (163), a second rotor (131), a stator (141) and, wherein the first rotor, second rotor and stator are arranged concentrically about a shaft (50), and at least one of the second rotor and the stator is adapted to accommodate the support structure. An electrical machine is also provided comprising a shaft (50) having an axis, at least one first rotor (321), at least one second rotor (331), at least two stators (341a), (341b) and, wherein the first rotor, second rotor and stators are arranged axially along the shaft and extend from the axis.

Abstract: In order to provide a magnetic pole-piece having good immunity to eddy currents while providing a high torque rating there is provided a magnetic pole-piece (60) comprising a magnetic part (64) and a retaining part (62), wherein the retaining part (62) supports the magnetic part (64).

Abstract: A wellbore rotating instrument system includes a source of rotational energy for transmission thereof to within a wellbore. At least one magnetic gear assembly is coupled at its input to an output of the source. A rotating load is coupled at its input to a rotational output of the magnetic gear assembly. The at least one magnetic gear assembly comprises a housing, a stator disposed in the housing proximate an inner wall thereof, a second shaft rotatably supported on bearings disposed at longitudinally spaced apart locations inside the housing and a first shaft rotatably supported inside the output shaft. The stator comprises a plurality of magnets disposed in generally circular laminations. The second shaft comprises a non-magnetic, electrically non-conductive body and a plurality of pole pieces disposed circumferentially therearound. The first shaft comprises magnets disposed around its exterior circumference and shaped to fit rotatably within the second shaft.

Abstract: A magnetic gear comprising: a first movable member having a first set of magnetic poles, a second movable member having a second set of magnetic poles, and a third movable member having a set of pole pieces; wherein the first and second members have magnetic poles at different spacings and the pole pieces are arranged to modulate the magnetic field acting between the magnetic poles, and control means arranged to control rotation of one of the members so as to vary the gear ratio between the other two members.

Abstract: Embodiments of the present invention relate to magnetic gears comprising first and second moveable members arranged to interact in a magnetically geared manner via a first electrical winding arrangement arranged to generate, at least in part, a first magnetic flux having a first number of pole-pairs, and one or more pole-pieces arranged to modulate the first magnetic flux to interact with a second magnetic flux having a second number of pole-pairs, wherein the first number of pole-pairs is less than the second number of pole-pairs.