System model of proton-exchange membrane fuel cell and its application in solving the tasks of diagnostics and control of operating modes

The construction of systems for online monitoring of the technical state of hydrogen fuel cells by analyzing their electrical fluctuations during operation was explored. A system model of proton-exchange membrane fuel cells that considers the relationships between input and output signals as a source of diagnostic information was described. The results show that only an adapted small-signal system model enables effective online diagnostics. The use of electrical fluctuations for early detection of critical operating modes and taking timely corrective control actions was illustrated by maintaining the water balance in a membrane electrode assembly as an example. The possibility of detecting modes with excessive and insufficient humidification based on the analysis of the spectral characteristics of electrical fluctuations was established. The critical modes and faults of solid polymer fuel cells detectable through electrical fluctuations were examined.