2-D FEM Tuned Analytical Approximation for Fringing Permeances

  • Vencislav Valchev
  • Alex Van den Bossche
  • Todor Filchev
Part of the Mathematics in Industry book series (MATHINDUSTRY, volume 4)


This paper presents an analytical approach for calculating fringing permeances in gapped inductors. For most of the gapped inductors, the permeance of other field paths out of the air gap (the fringing paths) is not negligible. Existing three-dimensional modelling techniques using finite element analysis for magnetic components are accurate, but require prohibitive amount of simulation time. Twodimensional models are often used, but the accuracy is low as a 2D simulation fails taking into account important 3D effects. We present analytical approximations for fringing permeance calculation for the most usual field patterns, denoted as basic cases. The proposed fringing coefficients can be used to present all symmetrical cases and cases with multiple air gaps. The derived equations are sufficient for a normal engineering accuracy.


Basic Case Finite Element Method Simulation Gapped Inductor Flux Path Carter Fact 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2004

Authors and Affiliations

  • Vencislav Valchev
    • 1
  • Alex Van den Bossche
    • 2
  • Todor Filchev
    • 1
  1. 1.Department of ElectronicsTechnical University of VarnaBulgaria
  2. 2.Department of Electrical Energy, Systems and AutomationGhent UniversityBelgium

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