Extraction of temperature-dependent thermoelectric material parameters of a thermoelectric cooler by the non-linear least squares method

Abstract

This paper presents a method of extracting temperature-dependent parameters of thermoelectric material from the operating conditions of thermoelectric cooler (TEC). Based on the finite element method of calculating TEC's performance, non-linear least squares method is used for extracting temperature-dependent material parameters including the seebeck coefficient, electrical resistivity and thermal conductivity (Α, ρ, Κ) as operating current, thermal load and hot end temperature are taken as inputs and cooling temperature is taken as output. To further improve the voltage calculation accuracy, the electric resistance error factor which includes electrical contact resistance and the calculation model error is extracted with the voltage being output on the basis of extracted material parameters. The cooling temperature and voltage of another TEC with the same thermoelectric material are recalculated by the extracted parameters and the exact parameters provided by manufacturer respectively. Compared with the experimental results, the extracted material parameters have the advantages of high accuracy, wide application ranges and easily implementing in evaluating TECs' performance.