US 5,705,902 A · Halbach array DC motor/generator

Abstract

A new configuration of DC motor/generator is based on a Halbach array of permanent magnets. This motor does not use ferrous materials so that the only losses are winding losses and losses due to bearings and windage. An "inside-out" design is used as compared to a conventional motor/generator design. The rotating portion, i.e., the rotor, is on the outside of the machine. The stationary portion, i.e., the stator, is formed by the inside of the machine. The rotor contains an array of permanent magnets that provide a uniform field. The windings of the motor are placed in or on the stator. The stator windings are then "switched" or "commutated" to provide a DC motor/generator much the same as in a conventional DC motor. The commutation can be performed by mechanical means using brushes or by electronic means using switching circuits. The invention is useful in electric vehicles and adjustable speed DC drives.

Claims28

Dependent claims

An electric machine, comprising:

a cylindrical rotor comprising an array of permanent magnets that provide a uniform dipole field with no necessity for the use of laminated iron, wherein said array of permanent magnets comprise bars of identical permanent magnets assembled in a circle, wherein said bars are dipole elements, each bar of said bars having a vector direction of magnetization that rotates at twice the rate as that of a vector rotating about said circle pointing from the center of said uniform dipole field to the center of said elements;
a stator inserted down the axis of said dipole field, said stator comprising windings;
and
means for commutating said windings;
wherein said rotor is on the outside of said stator.

2 more elements

Dependencies are inferred from the claim text.

Halbach array DC motor/generator

Life of this patent

Halbach array DC motor/generator

Life of this patent

Abstract

Claims28