Numerical average value modeling of second order flyback converter in both operational modes

Abstract

Average-value modeling (AVM) provides an efficient tool for studying power electronic systems, including DC/DC converters. Analytical derivation of average models that are valid in different operating modes is difficult, especially when parasitics and non-idealities are included in converter circuit. Recently, a numerical computer-aided method of obtaining the average-value model of power electronic systems has been proposed based on corrected state space average-value modeling, wherein several parametric functions are obtained using the detailed simulation. This paper considers the second order flyback converter, which has transformer isolation and additional losses that have not been sufficiently addressed in the prior literature. The paper extends the parametric AVM approach and suggests a modified averaged circuit model for this type of converter. The proposed models are compared in predicting both large signal time-domain transients and small-signal frequency domain characteristics.