Design and Energy Management Comparison of Fuel Cell Hybrid Power System for Underwater Unmanned Vehicle

Underwater unmanned vehicle (UUV) has become the focus of military science and technology research in various countries around the world due to its high concealment, environmental adaptability and strong autonomy. Among them, endurance determines the performance of UUV, and the key to endurance lies in the power system. Fuel cell has the advantages of high specific energy, high energy conversion efficiency, wide output power range, zero emission, pollution-free, and low noise. It is an ideal power source for UUV. However, the fuel cell has difficulties in cold start, slow dynamic response, and soft output characteristics. It requires batteries to start and peak regulation to improve the life of the fuel cell system. For this reason, this paper conducts research on the hybrid power system composed of fuel cell and battery: first, the entire system was designed, and the system topology was determined in consideration of factors such as efficiency and volume. Then, the optimal capacity allocation of fuel cell and battery was analyzed using the principle of discrete minima. Finally, in order to improve the performance of the hybrid power system, rationally allocate the fuel cell and battery in the UUV working process, several common energy management strategies are briefly introduced and a hardware-in-the-loop simulation platform is used to verify and summarize different energy management strategies. Select appropriate energy management strategies according to different actual needs.