Magnetic Circuits: Inductors and Permanent Magnets

  • Ewald F. Fuchs
  • Mohammad A. S. Masoum


Static magnetic devices used in electromechanical energy conversion processes (e.g., rotating machines, rectifiers, inverters) are inductors and (permanent) magnets: their operation is based on Maxwell’s equations [1] and in particular for low-frequency (f < 50 kHz) applications on Ampere’s and Faraday’s laws neglecting displacement currents. Although the nonlinear characteristics of iron cores will be discussed in one of the following subsections, mostly ideal characteristics, that is, no iron-core losses (PFe = 0) and an infinitely large relative permeability (μr = ∞) will be assumed in this chapter. Computer-aided measurement techniques are introduced for measuring, as a function of frequency, small loss levels (few watts), impedances, resistances and inductances of inductors as used in solid-state energy conversion devices.


Flux Density Magnetic Circuit Ferromagnetic Material Electrical Steel Dipole Magnetic Moment 
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Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  1. 1.Department of Electrical, Computer, and Energy EngineeringUniversity of ColoradoBoulderUSA
  2. 2.Department of Electrical and Computer EngineeringCurtin UniversityPerthAustralia

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