Optimization of an on-board fuel cell system for submarine operation

Abstract

The goal of this research is to model, simulate, and optimize an AIP (air independent propulsion) system for submarines. The basic submarine power plant platform chosen for the simulations is the diesel generator with fuel cells. ☐ The submarine simulator was formulated in Matlab/Simulink with a dedicated model for every onboard subsystem such as the diesel generator, the battery, the fuel cell, as well as propulsion and hotel loads. The simulator was validated with performance data obtained from a standard conventional submarine. Considering the physical volume of the equipment and required fuels, four power plant configurations are suggested. The baseline configurations consist of three 1500kW diesel generator systems and no fuel cells (3/0). The other three configurations were defined by sequentially replacing each diesel generator with a 240kW fuel cell, viz. two diesels with one a 240kW-FC (2/1), one diesel with a 480kW-FC (1/2), and a 720kW-FC only (0/3). ☐ Analyzing various submarine operations (anti-surface ship/submarine warfare, land attack operation, intelligence gathering mission, and network-centric warfare), we formulated four representative duty cycles which are expressed as velocity vs. time profiles. The power plant configurations were implemented into our simulator, and we obtained results for diesel/hydrogen consumption, and battery state-of-charge vs. time. The optimal configuration was obtained as one diesel with a 480kW-FC (1/2). ☐ Finally, we suggested other practical applications of our simulator and presented some examples. We then forecast potential deployments of fuel cell systems in the naval security environment.