Power Management Optimisation of a Battery/Fuel Cell Hybrid Electric Ferry

This paper presents a power management optimisation method for a hybrid electric ferry where a fuel cell is used as the primary source of power and a battery to cater the fast changes in the propulsion load. Efficiency of the fuel cell is taken as the optimisation objective and maintaining the power balance and battery state of charge during the round-trip are taken as constraints. A semi-empirical model of the fuel cell efficiency is derived to formulate the optimisation problem which is then used with the fmincon function in MATLAB to solve the optimisation problem. Optimum values generated by the fmincon algorithm is used as the power reference for the fuel cell. Simulation results validate the fuel cell power commands generated by the optimisation algorithm and the power balance and state of charge of the battery are maintained within the specified range.