An Electrical Analogy Model for Thermoelectric Generator under Natural Convection Conditions by Considering Nonlinear Heat Transfer with Ambient Environment

Thermoelectric energy harvesting offers a promising approach for utilizing environmental micro‐energy. Developing an accurate electrical analogy model for thermoelectric generators (TEGs) is crucial for advancing this technology, as it enables integration into existing commercial simulation software. In this paper, an electrical analogy model considering nonlinear heat transfer between module and environment is proposed. By introducing the nonlinear heat transfer branches of cold‐side, hot‐side, and heatsink, the proposed model accurately describes the influence of natural heat convection and heat radiation on the temperature of TEG module. A parameter extraction method based on multi‐objective optimization is presented to determine challenging‐to‐calculate model parameters, including nonlinear heat dissipation parameters and temperature‐dependent material parameters. The non‐dominated Sorting Genetic Algorithm II (NSGA‐II) is employed to solve the optimal solution. The experimental results show that by virtue of the identified parameters, the proposed model accurately reflects the thermal dynamic characteristics and output variations of the TEG module under natural convection conditions. The maximum estimation accuracies of the TEG temperature and output voltage by the proposed model can reach 90.82% and 90.29%, respectively, which are significantly higher than those achieved by the traditional electrical analogy model.