Energy management strategy based on CEEMDAN and fuzzy logic control for hybrid power system of ship

An energy management strategy (EMS) based on complete ensemble empirical mode decomposition with adaptive noise(CEEMDAN) and fuzzy logic control is proposed for a multi-power hybrid system consisting of fuel cell (FC)/battery (BAT)/supercapacitor (SC) in a hydrogen powered ship. The EMS manages and controls the balance between different types of energy and load requirements to ensure system stability and reliability. CEEMDAN is used to decompose the demand power signal of ship. The CEEMDAN filtering order is set according to the significant difference between the energy of the low and high frequency intrinsic mode functions (IMF). The filtering order is adjusted in accordance with the limits required for the FC output power fluctuation rate. The low frequency power demand component that meets the volatility requirements is allocated to the FC and the high frequency component is shared by BAT and SC. The real-time state of charge (SOC) of BAT and SC is judged and further optimized by fuzzy logic control to prevent SC from over-charging and over-discharging. The simulation results prove that the proposed EMS can ensure the FC output power is in a reasonable range while stabilizing the SOC of BAT and SC in the appropriate interval, therefore improving the lifetime of the hybrid system.