Small-signal modelling of current-programmed N-connected parallel-input/series-output bridge-based buck dc-dc converters

A procedure is established for the small-signal modelling of n-connected current-programmed parallel-input/series-output pulse-width modulated bridge-based buck dc-dc converters operating in the continuous-current conduction mode. State-space averaging is used to represent the power stage while current-mode control is modelled using a modified new continuous-time technique. Approximate analytical expressions of the major small-signal transfer functions that include the number of modules as a variable are proposed. PSpice simulations are carried out to validate the analysis.