Novel dynamical modeling for series-parallel resonant converter

Extended describing function method is one of the commonly applied state-of-the-art methods for dynamical modeling of series-parallel resonant power converters. Thanks to the relative good sinusoidal voltage waveform across the parallel capacitor C
p
it has a good modeling accuracy under light and medium load conditions. However, under heavy load condition this method becomes inaccurate due to the distortion of the voltage across C
p
.