Abstract:
Batteries are gaining momentum in the dawn of the global energy transition. Their propensity to early ageing remains, however, a serious concern. Reasons for this include thermal and electrical stresses experienced during operation. The combination of batteries with supercapacitors (SC) into hybrid energy storage systems (HESS) is currently regarded as an effective means of reducing electrical stress on batteries. However, battery-SC HESS still plays a marginal role in practice. Anticipating a possible resurgence of interest in this technology, controllers should be designed to enable easy conversion of existing battery energy storage systems (BESS) into battery-SC HESS. Currently, most control models in the literature would require significant modifications to the existing infrastructure, hindering the expected transition to the HESS. This paper introduces a fuzzy logic controller for plug-in SC aiming for straightforward conversion of BESS into battery-SC HESS. In addition to relieving batteries from fast-varying currents, the SC can contribute in the supply of slow-varying currents to further relieve the battery from electrical stresses and assist in regulating the battery temperature. Extensive simulations indicate that peak currents of batteries can be reduced by up to 26.20% under normal operation, and their temperature slope by up to 38.15% under high temperature conditions.
