Calculation of the reversible permeability for ferrite cores with uniform and non uniform cross section

摘要

The material behavior of a ferrite core under DC bias conditions is described with the reversible permeability #um#_rev vs.the applied DC magnetic field H_DC.To calculate #um#_rev vs.H_DC various core structrues it is necessary to know #um#_rev as a functin of the DC flux density B_DC.A method is developed to determine #um#_rev vs. B_DC from measurements of #um#_rev vs.H_DC on an E-core with approximately uniform cross section.Those data are taken to calculate the DC-bias behavior of an ETD39 core and an EP13core.The ETD39 core sturcture represents a core with approximately uniform ross section and the EP 13 core structure represents a core with strongly non uniform cross section.the usage in the determination of DC-bias limits is demonstrated.