Two-Level Energy Management Strategy for a Hybrid Power System Based Multi-Stack Fuel Cell

A multi-stack fuel cell hybrid power system architecture including three fuel cell systems and a battery is developed. The efficiency analysis and calculation are carried out based on the power loss of the multi-stack FC system. This paper proposes a two-level multi-stack coordination energy management strategy which consists of multi-stack FC system control level and multi-stack FC/Battery hybrid system control level. The method of multi-stack FC system control level is based on maximum efficiency range for a multi-stack fuel cell system to achieve high efficiency. The coordinate control of multiple power sources realizes the effective distribution of demand power, avoids the transients and rapid changes of demand power, and enhances the overall efficiency of the system. A hybrid system model is built and the proposed strategy is evaluated with a real driving cycle. The results of the proposed strategy show promising improvement in the overall performance of the system.