An averaged large-signal modeling method for resonant converters

An averaged large-signal modelling method for resonant converters is presented, which is based on the classification of the state variables according to their dynamic behaviour. The modelling technique is applied to a series-parallel resonant converter, which is controlled for switching at zero-resonant current. Based on the averaged model, a sliding mode controller for this resonant converter is proposed, which provides robustness in relation to external disturbances and a good dynamic response of the output voltage.