Rotor apparatus for high strength undiffused brushless electric machine

Patent · Tue Jan 24 04:00:00 EST 2006

OSTI ID:880466

Hsu, John S ^[1]

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1. Oak Ridge, TN

A radial gap brushless electric machine (30) having a stator (31) and a rotor (32) and a main air gap (34) also has at least one stationary excitation coil (35a, 36a) separated from the rotor (32) by a secondary air gap (35e, 35f, 36e, 36f) so as to induce a secondary flux in the rotor (32) which controls a resultant flux in the main air gap (34). Permanent magnetic (PM) material (38) is disposed in spaces between the rotor pole portions (39) to inhibit the second flux from leaking from the pole portions (39) prior to reaching the main air gap (34). By selecting the direction of current in the stationary excitation coil (35a, 36a) both flux enhancement and flux weakening are provided for the main air gap (34). Improvements of a laminated rotor, an end pole structure, and an arrangement of the PM elements for providing an arrangement of the flux paths from the auxiliary field coil assemblies are also disclosed.

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
• DOE Contract Number: AC05-00OR22725
• Assignee: UT-Battelle LLC (Oak Ridge, TN)
• Patent Number(s): 6,989,619
• Application Number: 10/848450
• OSTI ID: 880466
• Country of Publication: United States
• Language: English