Fuzzy gain scheduling control of switch-mode DC/DC converters

Abstract

This work proposes a model based fuzzy controller as a control technique for switch-mode DC/DC converters. These systems have a nonlinear dynamic behavior, as they work in switch-mode. Moreover, they are exposed to significant variations which may take these systems away from nominal conditions, due to changes on the load or on the line voltage at the input. In this paper we analyze the equations of a buck converter and propose a fuzzy gain scheduler among local models based on several operating points. We design a simple state feedback control law for every one of the local models and a fuzzy rule, which acts as a scheduler. The proposed fuzzy control is evaluated by means of computer simulations of these models for reference output, load regulation and line regulation.