Online Diagnosis Method of Water Management Faults Based on Hybrid-Frequency Electrochemical Impedance Spectroscopy for PEMFC

To swiftly accomplish online fault diagnosis of water management for proton exchange membrane fuel cell (PEMFC), an online diagnosis method of water management faults based on hybrid-frequency electrochemical impedance spectroscopy is proposed. First, guided by the principle of time-frequency signal processing, the online diagnosis of water management faults is conducted via the full-frequency band electrochemical impedance spectroscopy and the characteristic information of the abscissa coordinates at the intersection of high and low frequencies in electrochemical impedance spectroscopy. Subsequently, an online diagnosis method of water management faults based on hybrid-frequency electrochemical impedance spectroscopy is proposed to enhance the diagnostic speed. To validate the effectiveness and feasibility of the proposed method, a test platform is established, and numerous tests and analyses are conducted on PEMFC under diverse operating conditions. Experimental results demonstrate that the proposed method can accurately and swiftly identify various faults of water management in PEMFC, achieving a diagnostic accuracy of 95.56%, with a diagnostic duration of approximately 4 s.