A computational small-signal modeling technique for switch mode power converter

A computationally efficient method for obtaining the small-signal model of a switch mode power converter operating in the continuous conduction mode is presented. To apply this proposed technique, the only analytical work involved is the derivation of the two switched circuits of a given switch mode power converter in state-space representation form, and the developed computer simulation program provides a good approximated small-signal model in the form of open-loop Bode plots. The proposed modeling technique is applied to the buck converter and the derived model is compared with the small-signal model obtained using the statespace averaging technique. To further verify the validity of the proposed modeling technique, a 24W buck converter was built to demonstrate the effectiveness of the proposed modeling technique.