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Title: System and method for preventing stator permanent magnet demagnetization during vacuum pressure impregnation

Abstract

A permanent magnet electrical machine includes a stator having conductive windings wound thereon and one or more permanent magnets embedded in the stator. A magnetic keeper element is positioned on the stator so as to form a magnetic flux path with the permanent magnets, with the magnetic keeper element closing the magnetic flux path of the permanent magnets by providing a low reluctance flux path to magnetic flux generated by the permanent magnets. A vacuum pressure impregnation (VPI) process is performed on the stator to increase a thermal conductivity of the windings, with the VPI process including a curing step that is performed at a selected temperature. The magnetic keeper element sets an operating point of the permanent magnets to an internal flux density level above a demagnetization threshold associated with the selected temperature at which the curing step is performed.

Inventors:
; ;
Publication Date:
Research Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EE) (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1361419
Patent Number(s):
9,673,667
Application Number:
14/337,469
Assignee:
GENERAL ELECTRIC COMPANY DOEEE
DOE Contract Number:
EE0005573
Resource Type:
Patent
Resource Relation:
Patent File Date: 2014 Jul 22
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING

Citation Formats

Raminosoa, Tsarafidy, Alexander, James Pellegrino, and EL-Refaie, Ayman Mohamed Fawzi. System and method for preventing stator permanent magnet demagnetization during vacuum pressure impregnation. United States: N. p., 2017. Web.
Raminosoa, Tsarafidy, Alexander, James Pellegrino, & EL-Refaie, Ayman Mohamed Fawzi. System and method for preventing stator permanent magnet demagnetization during vacuum pressure impregnation. United States.
Raminosoa, Tsarafidy, Alexander, James Pellegrino, and EL-Refaie, Ayman Mohamed Fawzi. Tue . "System and method for preventing stator permanent magnet demagnetization during vacuum pressure impregnation". United States. doi:. https://www.osti.gov/servlets/purl/1361419.
@article{osti_1361419,
title = {System and method for preventing stator permanent magnet demagnetization during vacuum pressure impregnation},
author = {Raminosoa, Tsarafidy and Alexander, James Pellegrino and EL-Refaie, Ayman Mohamed Fawzi},
abstractNote = {A permanent magnet electrical machine includes a stator having conductive windings wound thereon and one or more permanent magnets embedded in the stator. A magnetic keeper element is positioned on the stator so as to form a magnetic flux path with the permanent magnets, with the magnetic keeper element closing the magnetic flux path of the permanent magnets by providing a low reluctance flux path to magnetic flux generated by the permanent magnets. A vacuum pressure impregnation (VPI) process is performed on the stator to increase a thermal conductivity of the windings, with the VPI process including a curing step that is performed at a selected temperature. The magnetic keeper element sets an operating point of the permanent magnets to an internal flux density level above a demagnetization threshold associated with the selected temperature at which the curing step is performed.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Jun 06 00:00:00 EDT 2017},
month = {Tue Jun 06 00:00:00 EDT 2017}
}

Patent:

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