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 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 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 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.