Feed-Forward-based Control in a DC–DC Converter of Asymmetric Multistage-Stacked Boost Architecture

Artikel i vetenskaplig tidskrift, 2016

A new feed-forward control technique for a dc-dc step-up converter based on the asymmetric multistage stacked boost architecture (MSBA) is proposed. The developed feed-forward controller directly handles the load current and the perturbations that may be caused by the dynamic operation of the converter. Thus, there is no time delay for estimating the error in a control process, and therefore, both robust steady-state operation and high dynamic performance can be achieved. The asymmetric MSBA dc-dc converter is a single-output high-voltage topology that embodies several in-series active voltage-balancing circuits. Thus, there is a need for an improved balancing control method. This can be accomplished by replacing the conventional proportional-integral controllers with feed-forward type and therefore improved balancing between the stages can be attained, because the steady-state errors are suppressed and the dynamic response can be enhanced. A thorough theoretical analysis is conducted for verifying the stability of the suggested feed-forward control technique in an asymmetric MSBA converter, and selective simulation and experimental results are demonstrated in order to validate the effectiveness and feasibility of the proposed control scheme.