Fast Electrochemical Impedance Spectroscopy Detection for PEMFC Based on Four-phase Interleaved Boost Converter

Electrochemical impedance spectroscopy (EIS) of proton exchange membrane fuel cell (PEMFC) can respond to the stack's internal characteristics. The EIS is also the effective technology for the fault diagnosis and state-of-health estimation of PEMFC stacks. However, conventional EIS detection methods have disadvantages of long operating times, high costs and adverse effects of the stacks' normal operation. To address these problems, a fast PEMFC EIS detection method based on four-phase interleaved boost converter is proposed. To ensure the high bandwidth of excitation current signal for EIS detection, a model predictive control (MPC) of the current loop for the interleaved converter is developed. In addition, to shorten the EIS detection time and mitigate the adverse effects on the system due to EIS detection, an optimized time division multisine signal (OTDMS) is constructed. For the above excitation signal, to minimize the peak value, the binary search and graph matching algorithm are used to find the optimal excitation order of frequency and the particle swarm optimization (PSO) algorithm is used to find the best phase of each multisine signal. Simulation results show that the proposed method can realize wide frequency range EIS detection in a short time and the adverse effects on the system are reduced.