Identification of Equivalent Circuit Parameters for Proton Exchange Membrane (PEM) Electrolyzer Engineering Models

Abstract

This paper addresses the problem of underestimated temperature measurements in practical proton exchange membrane (PEM) electrolyzer engineering due to heat losses by enhancing the existing second-order RC equivalent circuit model of PEM electrolyzers. We present a novel engineering circuit model for PEM electrolyzers, incorporating the effects of heat losses from gases and pipelines. The objective is to enhance the model’s ability to predict electrolyzer performance and align control strategies with the realities of engineering practice. However, the PEM electrolyzer model is complex, being time-varying and nonlinear due to multi-physics field coupling. The parameters of the equivalent circuit are changed by the electrical energy input and its own state. To tackle the problem of parameter variation, firstly, a recursive identification algorithm is employed to estimate the internal equivalent circuit parameters of the engineering model. Then, the additional resistance is fitted according to the relationship between heat loss and current to complete the engineering circuit model identification. Finally, using MATLAB to construct an engineering model and validate the effectiveness of the proposed identification algorithm.

Keywords

• Proton exchange membrane (PEM)
• engineering circuit mode
• parameter identification
• recursive identification algorithm
• curve fitting
• system simulation