Large-signal modelling of the PRC-LCC resonant topology with a capacitor as output filter

In this paper, two mathematical models are presented to approximate, accurately enough, the large signal dynamical behaviour and the steady state behaviour of the PRC-LCC resonant topology with a capacitor as output filter. The method used to obtain these models is based on applying the extended describing function and the generalised averaging modelling techniques. Therefore, the evolution of the topology waveforms, most of them sinusoidal, is approximated by their corresponding envelope. These envelopes are expressed by a set of nonlinear differential equations which are solved numerically with the help of a computer. The resulting algorithm is faster than a straight PSpice simulation and free of convergence problems. Finally, the good concordance between the models and the practice is verified with a wide set of experimental results.