Effects of Circuit Parameters on Dynamics of Current-Mode-Pulse-Train-Controlled Buck Converter

Abstract

Current-mode pulse train (CMPT) control technique, a novel discrete control technique for switching dc-dc converters, has completely different dynamics from the traditional pulsewidth modulation control technique. In this paper, a 1-D normal form of discrete-time map of CMPT-controlled buck converter operating in discontinuous conduction mode (DCM) is established, upon which the effects of the circuit parameters on the dynamics and the border collision bifurcation behaviors of CMPT-controlled DCM buck converter are observed and analyzed. According to discrete iterative maps of period-1, period-2, and period-3, the fixed point analyses of the corresponding periodicities are studied, and the mechanism of border collision bifurcation is revealed. Simultaneously, the parameter conditions of different periodicities are formulated, which are helpful to better understand the behaviors and to analyze the CMPT-controlled buck converter.