Stability Region Based Robust Controller Design for High-Gain Boost DC-DC Converter

In this article, we propose an analytical method to design a robust nonfragile controller for load voltage regulation of high-gain boost converter exhibiting nonminimum phase behavior due to right-half plane (RHP) zero. The proposed single-loop voltage-mode controller design technique is based on the stability boundary locus and Kharitonov's theorem. Using this approach, a robust performance region having guaranteed gain margin and phase margin criteria for nominal and 16 Kharitonov's plants are generated in the controller parameter plane. Controller robustness-fragility analysis due to the tolerance of analog compensator passive components is done with the help of a delta 20 robustness fragility index. Controller robustness, performance, and nonfragility are tested on a 200-W laboratory prototype against the load and source perturbations. Experimental results validate the effectiveness of the robust controller to regulate the load voltage of the converter in spite of the limit on performance set by RHP zero.