Economic Control for Hybrid-Electric Shipboard Microgrids Considering Battery Degradation and Cycling Life Costs

Electric ships are gaining popularity from large ships to small cargo ferries, with benefits in terms of environmental sustainability, operational flexibility, and operational efficiency. A shipboard microgrid with accurate life cycling cost functions for on-board energy storage systems (ESSs) is proposed, which explicitly integrate ESSs life cycle costs into the hierarchical control of shipboard microgrids. On the secondary control end, incorporating the impact of cycle depths would better the economic operation of electrified ships. Power dispatching signals are distributed from secondary controllers to primary controllers, which are designed to operate distributed energy resources such as turbines and ESSs. The proposed control architecture aims at filling existing gaps in the literature in terms of economic operation of electric ships via collective control of distributed resources in a robust manner.