A Review of Permanent Magnet Models Used for Designing Electrical Machines

This article serves as an overview of existing models of permanent magnets (PMs) for electrical machines. The review study starts with the linear recoil model, which is commonly used to describe the reversible part of the demagnetizing curve. It is a simple model, especially useful for representing...

Full description

Saved in:
Bibliographic Details
Published in:IEEE transactions on magnetics 2022-11, Vol.58 (11), p.1-19
Main Authors: Moree, Gustav, Sjolund, Jonathan, Leijon, Mats
Format: Article
Language:English
Subjects:
Angular demagnetization
Anisotropy
coercive field model
Coercivity
Demagnetization
Domain walls
Ferrites
High temperature
Inclination angle
Low temperature
Magnetic domain walls
Magnetic domains
magnetic field modeling
Magnetic flux
Magnetic hysteresis
Magnetism
Magnetization
magnetization model
Permanent magnets
permanent magnets (PMs)
Recoil
recoil permeability
Soft magnetic materials
Temperature
Temperature dependence
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:This article serves as an overview of existing models of permanent magnets (PMs) for electrical machines. The review study starts with the linear recoil model, which is commonly used to describe the reversible part of the demagnetizing curve. It is a simple model, especially useful for representing materials with high anisotropy, such as ferrite, NdFeB, and SmCo. The model is harder to apply for nonlinear materials, such as Alnico, but still possible since their recoil curves are linear. The study shows how the linear recoil model could be extended to include irreversible demagnetization, temperature dependence, and angular dependence. All such models have their advantages and disadvantages, which will be discussed further. Both the magnetization and the risk of demagnetization are temperature-dependent. It could be noted that NdFeB has an increased risk of demagnetization at high temperatures, while ferrite has it at very low temperatures. The temperature dependence is described and compared for several materials, also including simplifying models. There are different methods to include the inclination angle of an applied magnetic field when studying the demagnetization of PMs. Several models describe different phenomena associated with the underlying dynamics of magnetism. Such models could then consider coercivity mechanisms and coherent rotation of magnetization, both with the Stoner-Wohlfarth model and models of domain wall motions.
ISSN:0018-9464
1941-0069
1941-0069
DOI:10.1109/TMAG.2022.3200150