Real-time Power Management of Lithium-Ion Batteries in DC Microgrids

Abstract

Battery energy storage systems play a vital role in DC microgrid applications by addressing the uncertainty of renewable energy resource availability and electric vehicle charging. Li-ion batteries, in particular, are gaining attention in such applications due to their high-performance properties, including high specific energy and power density. However, Liion battery performance can vary during grid operation due to factors such as fluctuations in environmental temperature and battery degradation. To meet the varying power demands in a microgrid, an efficient power management scheme is essential to adapt battery generation power to consumed power demand in real time. Recent studies have demonstrated real-time methods based on broadband perturbations to rapidly and accurately determine battery impedance. From this, the battery output power can be estimated and utilized for energy storage power management. This paper presents an efficient power management technique that relies on real-time battery impedance measurement. Experimental results, based on commercial Li-ion battery cells, are provided to demonstrate the effectiveness of the proposed technique.