Abstract
This paper presents a systematic and unified approach to modeling PWM dc/dc converters using the layer scheme. With the layer scheme, the typical PWM converters, such as buck-boost, Cuk, Zeta and Sepic, can be derived from the two basic converter trees, buck and boost. The small-signal models of these converters can, therefore, be readily derived in terms of h-parameter (for buck family) and g-parameter (for boost family). Using the proposed approach can help to yield highly related dynamic models of the converters in a family. This merit has made the proposed modeling method become uniquely valuable.