Strategies for Preserving the Battery SOC in DC Shipboard Power systems

Nowadays, the energy storage solutions are reaching a more prominent role when integrated in DC shipboard power systems. Among others, batteries and supercapacitors are already capable of assisting the traditional on-board energy resources, both during normal operation (e.g. fuel consumption optimization, peak shaving, pulsed loads supply) and in critical situations. When a main source of energy goes out of service, the remaining online sources and the storage are to be proficiently managed, thus ensuring enough power to the vital loads without outages. In this scenario, the power sharing between the storage systems gets a notable importance, as an accurate load subdivision can actually extend the power-on time. The paper investigates different options to manage the Battery Energy Storage Systems of a DC shipboard power system. Two batteries are onboard installed to temporarily support the loads supply if a generating system disconnection occurs. Three power sharing profiles are investigated to identify the best solution in preserving the State of Charge of batteries.