Average modeling of Single Stage Flyback PFC ＋ Flyback DC／DC converter

With the use of this novel average model for Single Stage Flyback PFC + Flyback DC/DC converter, voltage control mode, peak current control mode and average current control mode can be simulated easily by changing the model's parmneters. It can be used to do various analysis not only for small signal and static behavior but also for large signal and dynamic behavior of the converter. By using this average model the simulation speed can be improved by 2 orders of rrmgnitude above that obtained by using the conventional switched model. It can be applied to optimize the trade-off between high power factor, voltage stress, current stress and good output performance while designing this kind of single stage PFC converter. A 60W single stage power factor corrector was built to verify the proposed model. The modeling principle can be applied to other Single Stage PFC topologies.