Evaluation of Primary-Side MOSFETs Losses in Resonant LLC Converters

Abstract:
The aim of this paper is to provide a model of the primary-side MOSFETs power losses in resonant converters. The model is based on the MOSFET waveforms, obtained from both simulations and experimentalmeasurements, and allows to split the losses between theMOSFET's sources of loss. The losses model adapts its equations to obtain more accurate results in all the operating conditions of the converter: above resonance, near resonance and below resonance.To validate the power losses of the model, the device’s case temperature was estimated and compared with the measured one.