Optimization of power allocation for the multi-stack PEMEC system considering energy efficiency and degradation.

With the large-scale application of the proton exchange membrane electrolysis cell (PEMEC), the power allocation of the multi-stack PEMEC system has attracted ever-growing attention. However, fluctuating power significantly affects the lifetime and energy efficiency of the system. In this work, a power allocation strategy of the system is proposed based on detailed modeling and characteristics analysis. A complete model of PEMEC is developed considering bubble coverage for research of operating characteristics. To analyze the energy efficiency characteristics of the system, a power model of the PEMEC stack is established. A mathematical method to real-time obtain the frontier of optimal energy efficiency of stacks is also proposed. The degradation model of the proton exchange membrane is developed to determine the safe operation boundary. And then considering the operating status, voltage degradation is introduced to characterize the degradation of PEMEC dynamically. Finally, a power allocation strategy is proposed considering the system's energy efficiency and degradation. Furthermore, a composite revenue function is presented to compare the performance of different power allocation strategies. The results show that the system has the highest consolidated revenue under the proposed strategy. Current work is conducive to the popularization and generalization of the multi-stack PEMEC system. • A comprehensive PEMEC model considering the bubble coverage effect is developed. • A method to improve the performance of the multi-stack PEMEC system is proposed. • The safe operational boundary of PEMEC is studied based on the PEM degradation model. • The voltage degradation to define the dynamical degradation of PEMEC is introduced. • A power allocation strategy is suggested considering energy efficiency and degradation. [ABSTRACT FROM AUTHOR]