Initial Permeability of Ferrite core


Magnetic permeability (µ) is the ability of a magnetic material to support the formation of a magnetic field. The initial permeability (µi) is the purely amplitude permeability of the ferrite core when the magnetic field (B) is close to “zero” as shown in the below B-H curve figure.


The magnetic permeability (µ) can be interpreted as “conductivity for magnetic flux”. The initial permeability is determined by the following formula, which is related to the applied magnetic material, its dimensions and shape.


  • where L = effective self-inductance(H)
    N = number of turns
    l = average length of magnetic path in the core(mm)
    A = cross-sectional area of cores(mm²)