Large signal average model for an Extended Duty Ratio and conventional Buck

Abstract

This paper provides a new large signal modeling approach for Buck type DCDC converters. Small signal models are typically only valid for small deviations in the duty ratio. Such models fail to capture large signal dynamics of the duty ratio if lossy switches are considered. The proposed model tracks large signal dynamics and also accurately captures the conduction losses from the on-state resistance of switches. The modeling approach is applied to a conventional Buck converter as well as the 2-phase Extended Duty Ratio Buck converter. The model is also generalized to accommodate the M-phase configurations of the Extended Duty Ratio topology.