Large-signal analysis and control of buck converters loaded by DC-DC converters

The dynamic behavior of the buck converter feeding downstream DC-DC converters is studied in this paper. DC-DC converters acting as a load are modeled as constant power loads except at low voltage, where the behavior of the start-up circuitry is included. A comprehensive large-signal analysis of a buck converter including over-current protection and feeding the described load is performed. This paper addresses the transient process of the converter's start-up and turn on/off of loads consisting of DC-DC converters and gives design considerations to assess performance and stability robustness of a simple proportional-derivative controller.