Large-signal linearization of a boost converter

Abstract

Various methods to linearize the large-signal control-to-output behavior of a boost converter are discussed. Most of the previously reported linearizing techniques are not suitable when the reference input amplitude or operating frequency is large. In this paper, a dynamic linearizing modulator (DLM) for the boost converter is proposed, which transforms the open-loop converter into a linear amplifier with an operating frequency as high as one-fifth of the switching frequency. The modulator generates the duty by comparing the non-linear part of a boost converter dynamic equation with a sine wave reference voltage on a cycle-to-cycle basis. The technique exhibits superior audio-susceptibility due to the feed-forward of input voltage. The formulation, implementation, and verification of this technique are discussed. Experimental results show that the output voltage is able to track a large-signal reference input upto one-fifth the switching frequency.