Due to the complex reaction mechanism and closed structure of proton exchange membrane fuel cell (PEMFC), on-line measurement and detection are challenging. Also, the uneven distribution of reactants and products in all directions within the PEMFC, so it is essential to measure and predict the local current density distribution. In order to measure and identify the operating parameters accurately, timely, and quickly, it is necessary to improve the detection means of the fuel cell system.
Based on the distributed (printed circuit board) PCB measurement technology, an integrated monitoring current distribution sensor system is designed. Combined with the structural parameters of the fuel cell, the selection scheme and layout scheme of measurement components are proposed. With the help of Altium Designer software, the PCB measuring circuit board is designed and made. Special design for the PCB structure is achieved to direct contact measurement with the plane of the bipolar board.
NI acquisition equipment with LabVIEW is used to collect and record the voltage of sampling resistors in XY plane of fuel cell single. Without changing the internal structure of the fuel cell, the in-plane voltage signal of the fuel cell is collected, and then the data are calculated and processed. So as to obtain the relevant information of impedance in-plane fuel cell single, after that, an AC signal is added, and the fast Fourier transform (FFT) is used to calculate the in-plane distributed impedance.
This circuit board has the characteristics of high integration. It realizes the on-line monitoring of the voltage and current density distribution in the fuel cell single XY plane and provides data support for the calculation of in-plane impedance and the analysis of the process of distributed polarization.