Electromagnetic field analysis on resonance phenomenon of inductor driven by inverter considering stray capacitance

Abstract

In inductors excited by the inverter using gallium nitride power devices, the ringing phenomenon, which occurs due to the multi-resonances during the short rise and fall time, increases noise and loss. To clarify the mechanism of the multi-resonances, the high frequency (HF) behaviors of a ring core inductor in frequency domain are measured and simulated by using the 2D electromagnetic field finite element analysis taking account of the stray capacitance. It is shown that the multi-resonances can be simulated, and the simulated results are in good agreement with the measured ones. To explain this phenomenon, a distributed-element circuit model including the stray capacitance of the ring core inductor is proposed based on the simulated results, it is shown that the proposed circuit model can represent the HF behaviors of the ring core inductor well.