Hamiltonian Point of View on Parallel Interconnection of Buck Converters Extended version

TL;DR

This paper applies Hamiltonian system theory to analyze and control parallel interconnections of buck converters, enabling energy-efficient, robust current sharing and voltage regulation without explicit load knowledge, validated through experiments.

Contribution

It introduces a Hamiltonian framework for decoupling current distribution from voltage regulation and proposes a robust control law that ensures optimal current sharing without explicit load information.

Findings

Control law achieves stable current sharing.

System converges to optimal current distribution.

Experimental validation confirms effectiveness.

Abstract

In this paper, parallel interconnection of DC/DC converters is considered. For this topology of converters feeding a common load, it has been recently shown that dynamics related to voltage regulation can be completely separated from the current distribution without considering frequency separation arguments, which inevitably limits achievable performance. Within the Hamiltonian framework, this paper shows that this separation between current distribution and voltage regulation is linked to the energy conservative quantities: the Casimir functions. Furthermore, a robust control law is given in this framework to get around the fact that the load might be unknown. In this paper, we also ensure that the system converges to the optimal current repartition, without requiring explicit expression of the optimal locus. Finally, resulting control law efficiency is assessed through experimental results.