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Title: Magnet management in electric machines

Abstract

A magnet management method of controlling a ferrite-type permanent magnet electrical machine includes receiving and/or estimating the temperature permanent magnets; determining if that temperature is below a predetermined temperature; and if so, then: selectively heating the magnets in order to prevent demagnetization and/or derating the machine. A similar method provides for controlling magnetization level by analyzing flux or magnetization level. Controllers that employ various methods are disclosed. The present invention has been described in terms of specific embodiment(s), and it is recognized that equivalents, alternatives, and modifications, aside from those expressly stated, are possible and within the scope of the appending claims.

Inventors:
; ;
Publication Date:
Research Org.:
General Electric Company, Niskayuna, NY (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1347536
Patent Number(s):
9,602,043
Application Number:
14/473,216
Assignee:
General Electric Company DOEEE
DOE Contract Number:
EE0005573
Resource Type:
Patent
Resource Relation:
Patent File Date: 2014 Aug 29
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING; 33 ADVANCED PROPULSION SYSTEMS

Citation Formats

Reddy, Patel Bhageerath, El-Refaie, Ayman Mohamed Fawzi, and Huh, Kum Kang. Magnet management in electric machines. United States: N. p., 2017. Web.
Reddy, Patel Bhageerath, El-Refaie, Ayman Mohamed Fawzi, & Huh, Kum Kang. Magnet management in electric machines. United States.
Reddy, Patel Bhageerath, El-Refaie, Ayman Mohamed Fawzi, and Huh, Kum Kang. Tue . "Magnet management in electric machines". United States. doi:. https://www.osti.gov/servlets/purl/1347536.
@article{osti_1347536,
title = {Magnet management in electric machines},
author = {Reddy, Patel Bhageerath and El-Refaie, Ayman Mohamed Fawzi and Huh, Kum Kang},
abstractNote = {A magnet management method of controlling a ferrite-type permanent magnet electrical machine includes receiving and/or estimating the temperature permanent magnets; determining if that temperature is below a predetermined temperature; and if so, then: selectively heating the magnets in order to prevent demagnetization and/or derating the machine. A similar method provides for controlling magnetization level by analyzing flux or magnetization level. Controllers that employ various methods are disclosed. The present invention has been described in terms of specific embodiment(s), and it is recognized that equivalents, alternatives, and modifications, aside from those expressly stated, are possible and within the scope of the appending claims.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Mar 21 00:00:00 EDT 2017},
month = {Tue Mar 21 00:00:00 EDT 2017}
}

Patent:

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  • A method and apparatus for field weakening in PM machines uses field weakening coils to produce flux in one or more stators, including a flux which counters flux normally produced in air gaps between the stator(s) and the rotor which carries the PM poles. Several modes of operation are introduced depending on the magnitude and polarity of current in the field weakening coils. The invention is particularly useful for, but not limited to, the electric vehicle drives and PM generators.
  • A method and apparatus for field weakening in PM machines uses field weakening coils (35, 44, 45, 71, 72) to produce flux in one or more stators (34, 49, 63, 64), including a flux which counters flux normally produced in air gaps between the stator(s) (34, 49, 63, 64) and the rotor (20, 21, 41, 61) which carries the PM poles. Several modes of operation are introduced depending on the magnitude and polarity of current in the field weakening coils (35, 44, 45, 71, 72). The invention is particularly useful for, but not limited to, the electric vehicle drives andmore » PM generators.« less
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