Design and performance evaluation of power system for unmanned ship based on proton exchange membrane fuel cell

To address the limitations of battery-powered unmanned surface vehicles (USVs) in terms of endurance mileage, this study introduces proton exchange membrane fuel cells (PEMFCs) into the power system of USVs. This paper focuses on the design and testing of a hybrid power system and its energy management strategy for a lightweight USV. The test results demonstrate that the hybrid power system effectively fulfills the power requirements of the USV across various operational conditions. Specifically, the amplitudes of bus voltage overshoot and undershoot remain below 0.31 V even during sudden changes in working conditions. The energy management strategy, in conjunction with an auxiliary battery, successfully limits the PEMFC power fluctuation to 200 W/s, thereby enhancing the lifespan of the PEMFC. Moreover, the study reveals that replacing Li-ion batteries with the PEMFC system as the primary power source can significantly enhance the USV's endurance mileage by 1.33-1.70 times carrying the same weight and 1.07-1.36 times carrying the same volume, respectively. And with increased hydrogen storage, the PEMFC system's energy density advantage over Li-ion batteries becomes more pronounced. These findings contribute to the exploration of PEMFCs as a promising solution for addressing the endurance limitations of battery-powered USVs, leading to their improved performance and extended operational range.