Fuzzy Logic Based Energy Storage Management System for MVDC Power System of All Electric Ship

In this paper, for supporting the medium voltage dc (MVDC) shipboard power system, an energy storage management (ESM) system based on fuzzy logic (FL) has been proposed and its performance with a proportional-integral (PI) control based ESM system is compared. In order to support the peak demand and pulsed load, a hybrid energy storage system incorporating high energy density storage (battery) and high power density storage (supercapacitor) is proposed. For energy transfer among the energy storages and the MVDC system, bidirectional dc-dc converters with dual active bridge (DAB) configuration are used. With the change of the bus voltage and load power demand, the ESM systems provide instantaneous reference powers for charging or discharging of the battery and supercapacitor. The reference powers for the battery and supercapacitor are sent to the respective controllers of the DAB converters. Two power sharing strategies are designed to share power among multiple energy storages. The MVDC shipboard power system with the generators, loads, battery, and supercapacitor with DAB converters are modeled in SimPowerSystems. Simulation results are used to make a comparison of performances of the FL and PI controller based ESM systems. Finally, controller hardware-in-the-loop based experimental results are added to demonstrate the effectiveness of the controller.