The symmetry properties of a magnetic levitation arrangement are exploited to produce spin-stabilized magnetic levitation without aligning the rotational axis of the rotor with the direction of the force of gravity. The rotation of the rotor stabilizes perturbations directed parallel to the rotational axis.

A magnetic bearing has two bearing members each of which carries a set of bearing elements. The bearing elements carried by one member are interleaved with the bearing elements carried by the other member to define three or more substantially parallel interleaf gaps between successive elements, so that bearing forces can be developed as a result of magnetic shear stresses acting across those gaps. The magnetic bearing achieves its bearing forces as the sum of force contributions from a number of...

A control device estimate a magnitude of a load applied to a magnetic bearing by processing a current instruction (Iref) issued by itself with a low-pass filter. The control device changes a control model in feedback control of the magnetic bearing in accordance with the estimated magnitude of the load, and calculates a control parameter such as a gain in the changed control model. Further, control device sets the calculated control parameter in a feedback controller performing actual feedback c...

An active type magnetic bearing for controllably supporting a rotatable shaft made of a magnetic material is constructed such that a stator made of an annular formed laminated iron core is provided around the rotatable shaft, a number of slots are formed along an internal surface of the iron core, stator windings of a number of phases are wound so as to be settled in the slots, thin sheet-like permanent magnets magnetized radially to provide a number of poles are secured onto the internal surfac...

A magnetic levitation control apparatus comprises a pair of electromagnets for holding a levitated body having a magnetic body in the levitated state. A signal source for supplying a voltage signal of a frequency on a level such that enables the electromagnets to function as the position sensor, wherein a control voltage signal for controlling the magnetic attraction of the electromagnets is superimposed on the voltage signal. A circuit differentially supplies the voltage signal to the pair of e...

A control system for an electromagnetic rotary drive for bearingless motor-generators comprises a winding configuration comprising a plurality of individual pole pairs through which phase current flows, each phase current producing both a lateral force and a torque. A motor-generator comprises a stator, a rotor supported for movement relative to the stator, and a control system. The motor-generator comprises a winding configuration supported by the stator. The winding configuration comprises at ...

In axial magnetic bearing apparatus in which a rotary disc made of a magnetic material is fixedly attached to a rotating shaft, and electromagnets are disposed on opposite sides of the rotary disc so as to have suitable very small distances therefrom respectively, so as to bear the rotating shaft axially in a non-contact state, a deep groove for forming an air layer having large magneto-resistance is provided all over the outer circumference of the rotary disc. Thus, formation of a magnetic circ...

A flywheel system incorporates a variable speed synchronous reluctance motor-generator and a variable speed permanent magnet generator for providing backup power. Rotating elements are supported by electromagnetic bearings and electric power provided by the backup generator maintains electromagnetic bearing operation during that portion of a coast down period when shaft speed falls below the minimum speed required for operation of the synchronous reluctance motor-generator.

The present invention provides a flywheel system with a variable speed synchronous reluctance motor-generator and a variable speed permanent magnet generator for providing backup power. The flywheel system incorporates rotating elements supported by electromagnetic bearings. Electric power provided by the backup generator maintains electromagnetic bearing operation during that portion of the coast down period when shaft speed falls below the minimum required for operation of the synchronous relu...

The present invention relates to a magnetic suspension bearing supported by magnetic force, which comprises one or more magnets fixed on a shaft directly or indirectly which can rotate with said shaft, and matching magnets provided in a certain space, wherein the magnetic polarity and magnitude of magnetic force of the matching magnets match with the magnetic polarity and magnitude of magnetic force of said one or more magnets to achieve the full suspension rotation of said shaft, and said magne...