Decentralized Power Management in Fuel Cell Battery Power Systems

Fuel cell-battery power systems are widely employed in various applications, and high-efficiency operation is an essential issue in reducing hydrogen consumption and lifespan extension. To ensure this target, the undesired operations of fuel cells, start-stop transition, heavy load, light load and load variation, should be avoided. In this paper, a decentralized power management strategy is proposed to realize both dynamic power allocation and steady-state operating point adjustment. In this method, based on the droop mechanism, the battery module not only takes over dynamic power, but also generates or absorbs steady-state powers in heavy- or light-load conditions, allowing the fuel cell to be immune to power variation and operate in the high-efficiency range as much as possible. Therefore, efficiency enhancement and lifespan extension are realized without communication, which ensures high reliability. Finally, the effectiveness of this power management solution is validated with experimental results in various conditions.