SPICE compatible averaged models of PWM full-bridge DC-DC converter

A novel systematic method is presented for modeling power stages with parasitics of multiswitch and/or transformer pulse-width-modulation (PWM) DC-DC power converters which operate in continuous conduction mode. The ideal switching part, which consists of ideal switches, ideal diodes, and an ideal transformer, is modeled by dependent current and voltage sources such that the DC current and voltage transfer functions are preserved. The validity range of the resulting bilinear model is addressed. The circuit models of the actual switching part are obtained by the addition of equivalent averaged parasitic components. The principle of energy conservation is used to derive equations for equivalent averaged resistances and equivalent averaged voltage sources of parasitic components. A reflection rule is introduced which allows simplification of circuit models. As an example, a procedure for modeling the full-bridge converter is given