A Modified-Optimal Energy Management Strategy of Fuel Cell- Battery Hybrid Energy Storage System for Marine Application

Considering the present limitations of battery technology, a hybrid combination of fuel cells (FCs) and batteries can be considered as one of the environment friendly, reliable, and efficient energy solutions for marine ship applications. However, proper energy and power management are some of the critical issues for fuel cell-based energy storage system (ESS) because the degradation of a fuel cell lifetime is strongly affected by its operating condition. In this paper, a modified-optimal energy management strategy (MOEMS) is proposed which determines the power-split ratio between the FC and battery efficiently. By integrating the popular gradient-descent algorithm into a state machine control the proposed controller is realized. The performance of the MOEMS is compared with conventional EMS with simulation. Results suggest that the proposed EMS improve the fuel cell lifetime by 44% while reducing the fuel consumption by 7% compared to the basic EMSs.