Optimization and Control of Electric Ship Microgrids With Short-Term Energy Storage Systems

The inertia of dc power system is very low in general compared to the traditional ac system’s inertia, necessitating the introduction of new concepts for shipboard dc power systems. This article proposes an innovative control structure for electric-ship dc system, which integrates ultracapacitor (UC) and superconducting magnet energy storage (SMES) energy storage systems (ESSs) to stabilize its microgrid with minimal voltage disturbance caused by the ship dynamic loads, while allowing dynamic close-loop rebalancing of the storage systems. New design and optimization methodologies, based on new dynamic system model, are presented and discussed. Power system performance has been assessed and validated through real-time hardware-in-the-loop (HiL) simulation and practical implementation of the control concept using DSP hardware.