Magnetic Fields and Materials

  1. John Chiasson

Published Online: 27 JAN 2005

DOI: 10.1002/0471722359.ch3

Modeling and High-Performance Control of Electric Machines

Modeling and High-Performance Control of Electric Machines

How to Cite

Chiasson, J. (2005) Magnetic Fields and Materials, in Modeling and High-Performance Control of Electric Machines, John Wiley & Sons, Inc., Hoboken, NJ, USA. doi: 10.1002/0471722359.ch3

Publication History

  1. Published Online: 27 JAN 2005
  2. Published Print: 18 MAR 2005

ISBN Information

Print ISBN: 9780471684497

Online ISBN: 9780471722359

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Keywords:

  • magnetic dipole moments;
  • magnetization;
  • B;
  • H;
  • M;
  • ideal magnetic materials;
  • B-H curve

Summary

This chapter goes into the modeling of magnetic materials in terms of their use in electric machines. The fundamental result of this chapter is the modification of Ampere's law so that it is valid in the presence of magnetic material. This introduces the magnetic intensity field H and its relationship to magnetic induction field B via the magnetization vector M to obtain the more general version of Ampere's law. All of this requires a significant discussion of the modeling of magnetic materials. The approximation H=0 in magnetic materials is discussed and then it is shown how this approximation along with Ampere's law can be used to find the radial component of B in the air gap of AC machines. Also presented is Gauss's law for B, which leads to the notion of conservation of flux, as well as the fact that B is normal to the surface of magnetic materials.