Symbolic Analysis of PWM DC-DC Converters operated under both Continuous and Discontinuous Conduction Modes

A computer analysis based on a linearized small-signal model of the ideal converter switching-cell (ISC) is presented. True rms values of the parasitic resistances of the converter are considered and kept outside this sub-circuit and this makes the ISC model general and suitable for the analysis of most of the dc-dc PWM power converters operated under both continuous and discontinuous conduction mode. Symbolic simulation program allows for an automatic derivation of the expressions for the four transfer function describing the frequency domain converter behaviour so that also higher order circuits can be easily studied. Converter models are generated by the program, that also allows for converter parasitic components to be taken into account with no need to derive cumbersome expressions.