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Title: Study on Enhancement and Weakening of Permanent Magnet Air-Gap Flux Density

Abstract

In a conventional permanent magnet (PM) machine, the air gap flux produced by the PM is fixed. It is difficult to enhance the air gap flux density because of limitations of the PM in a series magnetic circuit. However, the air gap flux density can be weakened by using power electronic field weakening to the limit of demagnetization of the PMs. This paper presents an analytical study for controlling the PM air gap flux density through a stationary brushless excitation coil. The air gap flux density can be either enhanced or weakened. There is no concern with demagnetizing the PMs during field weakening. The leakage flux of the excitation coil through the PMs is blocked. The prototype motors built on the principle of this analytical study confirm the capabilities of significant flux enhancement and weakening.

Authors:
 [1]
  1. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Power Electronics and Electric Machinery Research Facility
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE)
OSTI Identifier:
931702
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Conference
Resource Relation:
Conference: The IEEE International Electric Machines and Drives Conference, Antalya, Turkey, 20070503, 20070505
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING; DEMAGNETIZATION; EXCITATION; FLUX DENSITY; MAGNETIC CIRCUITS; MOTORS; PERMANENT MAGNETS; PROCESS CONTROL

Citation Formats

Hsu, John S. Study on Enhancement and Weakening of Permanent Magnet Air-Gap Flux Density. United States: N. p., 2007. Web.
Hsu, John S. Study on Enhancement and Weakening of Permanent Magnet Air-Gap Flux Density. United States.
Hsu, John S. Mon . "Study on Enhancement and Weakening of Permanent Magnet Air-Gap Flux Density". United States. doi:.
@article{osti_931702,
title = {Study on Enhancement and Weakening of Permanent Magnet Air-Gap Flux Density},
author = {Hsu, John S},
abstractNote = {In a conventional permanent magnet (PM) machine, the air gap flux produced by the PM is fixed. It is difficult to enhance the air gap flux density because of limitations of the PM in a series magnetic circuit. However, the air gap flux density can be weakened by using power electronic field weakening to the limit of demagnetization of the PMs. This paper presents an analytical study for controlling the PM air gap flux density through a stationary brushless excitation coil. The air gap flux density can be either enhanced or weakened. There is no concern with demagnetizing the PMs during field weakening. The leakage flux of the excitation coil through the PMs is blocked. The prototype motors built on the principle of this analytical study confirm the capabilities of significant flux enhancement and weakening.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}

Conference:
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