Control Pulse Combination-Based Analysis of Pulse Train Controlled DCM Switching DC–DC Converters

Pulse train (PT) control technique realizes the output voltage regulation of switching dc-dc converters by using preset high power control pulse P_H and low power control pulse P_L. In steady state, P_H and P_L in some successive switching cycles constitute a control pulse repetition cycle. The control pulse combination of PH and P_L in the control pulse repetition cycle has a significant effect on the performances of PT controlled switching dc-dc converters. In this paper, by taking PT controlled discontinuous conduction mode buck converter as an example, the control pulse combination of PT controlled buck converter is studied. Some lemmas to reveal the control pulse combination are presented, and the combination of P_H and P_L in a control pulse repetition cycle is obtained. Based on which, the steady-state and transient performances of PT controlled buck converter are investigated. The control pulse combination-based analysis of PT controlled buck converter provides an effective way to understand the PT control technique in detail.