The nonlinear behavior of the B-H relationship of a ferromagnetic material gives rise to two different types of permeabilities: ‘total permeability’ and ‘derivative permeability’. These are used in this study to define three inductances of a current dependent inductor that is built around a ferromagnetic core: ‘total inductance’, ‘derivative inductance’ and ‘energy related inductance’. The latter is the correct parameter to be used when calculating the energy stored in a current dependent inductor. Based on these inductance definitions, state equations for the various ‘inductances’ were developed and used to implement SPICE compatible models by applying behavioral dependent sources. The theoretical derivations of this work were validated by simulation and experimentally