A Stray Capacitances Model of Inductors with Partial Layer of Windings

With the high precision requirements of electronic devices, more accurate analysis and modelling of stray capacitance is required in order to reduce electromagnetic interference (EMI) from the stray capacitance in inductors. This paper proposes an improved analytical model of the stray capacitances of the inductor, which takes into account the capacitances between the windings and the central limb, the side limb and the yokes of the core. A general model of the stray capacitance with each winding as a complete layer is calculated, and the potential of the floating core is derived analytically. For the case of a partial winding layer near the side limb, calculations are derived and the stray capacitance changes are compared for different winding layers. Finally, the stray capacitance model of the partial layer is verified by finite element simulations and experimental results on the prototype.