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Title: System and method for heating ferrite magnet motors for low temperatures

Abstract

A system and method for heating ferrite permanent magnets in an electrical machine is disclosed. The permanent magnet machine includes a stator assembly and a rotor assembly, with a plurality of ferrite permanent magnets disposed within the stator assembly or the rotor assembly to generate a magnetic field that interacts with a stator magnetic field to produce a torque. A controller of the electrical machine is programmed to cause a primary field current to be applied to the stator windings to generate the stator magnetic field, so as to cause the rotor assembly to rotate relative to the stator assembly. The controller is further programmed to cause a secondary current to be applied to the stator windings to selectively generate a secondary magnetic field, the secondary magnetic field inducing eddy currents in at least one of the stator assembly and the rotor assembly to heat the ferrite permanent magnets.

Inventors:
; ;
Publication Date:
Research Org.:
GENERAL ELECTRIC COMPANY, Schenectady, NY (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1368187
Patent Number(s):
9,698,660
Application Number:
14/063,547
Assignee:
GENERAL ELECTRIC COMPANY DOEEE
DOE Contract Number:
EE0005573
Resource Type:
Patent
Resource Relation:
Patent File Date: 2013 Oct 25
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING

Citation Formats

Reddy, Patel Bhageerath, El-Refaie, Ayman Mohamed Fawzi, and Huh, Kum-Kang. System and method for heating ferrite magnet motors for low temperatures. United States: N. p., 2017. Web.
Reddy, Patel Bhageerath, El-Refaie, Ayman Mohamed Fawzi, & Huh, Kum-Kang. System and method for heating ferrite magnet motors for low temperatures. United States.
Reddy, Patel Bhageerath, El-Refaie, Ayman Mohamed Fawzi, and Huh, Kum-Kang. Tue . "System and method for heating ferrite magnet motors for low temperatures". United States. doi:. https://www.osti.gov/servlets/purl/1368187.
@article{osti_1368187,
title = {System and method for heating ferrite magnet motors for low temperatures},
author = {Reddy, Patel Bhageerath and El-Refaie, Ayman Mohamed Fawzi and Huh, Kum-Kang},
abstractNote = {A system and method for heating ferrite permanent magnets in an electrical machine is disclosed. The permanent magnet machine includes a stator assembly and a rotor assembly, with a plurality of ferrite permanent magnets disposed within the stator assembly or the rotor assembly to generate a magnetic field that interacts with a stator magnetic field to produce a torque. A controller of the electrical machine is programmed to cause a primary field current to be applied to the stator windings to generate the stator magnetic field, so as to cause the rotor assembly to rotate relative to the stator assembly. The controller is further programmed to cause a secondary current to be applied to the stator windings to selectively generate a secondary magnetic field, the secondary magnetic field inducing eddy currents in at least one of the stator assembly and the rotor assembly to heat the ferrite permanent magnets.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Jul 04 00:00:00 EDT 2017},
month = {Tue Jul 04 00:00:00 EDT 2017}
}

Patent:

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