Circuit-averaged and state-space-averaged-value modeling of second-order flyback converter in CCM and DCM including conduction losses

Modeling and analysis of basic DC-DC converters is essential for enabling power-electronic solutions for the future energy systems and applications. Many average-value modeling (AVM) techniques including state space averaging and circuit averaging have been developed over the years and available in the literature. Average-value modeling of ideal PWM converters neglects parasitics (losses) to simplify the derivations and modeling procedure. In this paper, we consider a second-order flyback converter with conduction losses parasitics. We propose two new AVMs using the circuit averaging and state space averaging approaches, respectively. By taking into account conduction losses, the accuracy of proposed average-value models improves. The new models are verified for large signal time-domain transients and small-signal frequency-domain analysis in continuous conduction mode (CCM) and discontinuous conduction mode (DCM). The derived (corrected) models show noticeable improvement over the traditional (un-corrected) models.