A Hierarchical Control-Based Energy Management Strategy for Multi-Stack Fuel Cell System with Performance Inconsistency

This study addresses the prevalent issue of performance inconsistency in multi-stack fuel cell systems (MFCSs) by proposing a hierarchical control-based energy management strategy (EMS). The proposed strategy consists of two main layers. The first layer develops a performance parameter prediction model for the fuel cell system (FCS), combining an improved grey wolf optimizer (IGWO) with semi-empirical models and using maximum power as the key performance indicator. The second layer introduces scaling factors to merge two objectives—reducing the operational load of underperforming FCS and improving system efficiency—into a single optimization objective. This approach aims to achieve the optimal distribution of load power. The simulation results show that, compared to the average distribution strategy and the chain startup strategy, the proposed strategy reduces hydrogen consumption by 2.96% and 19.4%, respectively. Meanwhile, the output energy of the underperforming FCS decreases by 26.51% and 48.25%, respectively. To further validate the proposed method, an MFCS test platform with rated powers of 200 kW and 120 kW is constructed for experimental testing. The experimental results indicate that the hierarchical control strategy achieves the lowest hydrogen consumption among the compared strategies. In conclusion, the EMS presented in this study demonstrates excellent performance, offering a practical solution to the performance inconsistency challenge in MFCSs.