Dynamic Modeling and Control of the LLC Resonant Converter

Due to the high power density, efficiency and ability to regulate the output voltage over a wide range, the resonant LLC converter has been one of the main choices in power converter designs. One characteristic of this converter is the absence of a constant operating point for the voltages and currents in the resonant tank, which makes it impossible to use mean value modeling techniques, as in pwm converters. In this context, this paper seeks to present the generalized averaging model theory to dynamically model the resonant LLC converter. Furthermore, it is also discussed about the linearization of this model and control aspects of the output voltage. The results show a good ability of the model to characterize the dynamics of the converter.