Closed-Loop Stability Analysis of Voltage Mode Buck Using a Proportional-Delayed Controller

Abstract : This paper focuses on the design of a P-δ controller for the stabilization of a buck DC/DC converter. The basis of this work is a geometric approach which allows to partition the parameters space into regions with constant number of unstable roots. The main contribution of the paper is that it provides an explicit tool to find P-δ gains ensuring the stability of the closed-loop system. In addition, the proposed methodology enables the design a non-fragile controller with a desired exponential decay rate σ. In order to illustrate the effectiveness of the proposed controller, some numerical examples are presented.