Nonlinear control algorithm of supercapacitor/Li-Ion battery energy storage devices for fuel cell vehicle applications

This paper proposes the operation of an energy storage devices consisting of a Li-Ion battery module and a supercapacitor (SC) bank for future transportation with a fuel cell (FC) as the main power source, so that FC vehicles (FCVs) with energy storage devices could result in reduced cost, improved fuel economy, lifetime, and performance. The study principally focuses on the original control law based on the flatness properties for a dc bus voltage regulation. Utilizing the differential flatness approach, we show simple solutions to the stabilization problems. To validate the proposed control algorithm, a small-scale test bench is realized in the laboratory. The control algorithm is digitally implemented by dSPACE controller DS1104. Experimental results with small-scale devices [a proton exchange membrane FC (PEMFC) of 1.2 kW, 46 A, and 26 V; a SC bank of 100 F, 25 V, and 500 A; and a Li-Ion battery module of 11.6 Ah, 24 V] corroborate the excellent performance during vehicle motor drive cycles.