Modelling of bidirectional CLLC resonant converter operating under frequency modulation

This paper proposes the application of three modelling techniques for analysis of bidirectional resonant converters with capacitor-inductor-inductor-capacitor (CLLC) compensation network operating under frequency modulation. Fundamental Mode Approximation (FMA), state-variable and cyclic-averaging models are obtained and compared. The simulation results for forward and reverse power flow direction are verified against Spice simulation and results obtained from literature. All models could successfully predict the behavior of the converter but state-variable and cyclic-averaging techniques showed better accuracy. Execution time is compared confirming that cyclic-averaging is the method with fastest execution.