Characterization and Modeling of a Virtual Air Gap by Means of a Reluctance Network

This paper deals with an analytical model of the virtual air gap (VAG) function in order to define design rules when this technique is used inside complex devices. The establishment of those design rules constitutes the main originality of the developments presented in this paper, which are about a single-phase magnetic core. It is based on the definition of a nonlinear reluctance network that takes simultaneously into account the effects of dc and ac magnetic flux components in the disturbed area that contains the VAG. The results are validated using a finite-element analysis and experimentally.