Analysis and modeling of effective temperature differences and electrical parameters of thermoelectric generators

We have derived an analytic model describing the interior temperature difference as a function of the load current of a thermoelectric generator (TEG); we have also proposed a method to extract the intrinsic and extrinsic Seebeck coefficients and resistances of TEG using experimental current–voltage curves. The decrement of internal temperature difference is almost linearly depending on load current of the TEG. From the experimental results, using a thermoelectric (TE) module with a thermal conductance of 3.52W/K and a parasitic thermal conductance of 50W/K, the effective internal electrical resistance was increased by approximately 5%, but the effective Seebeck coefficient was attenuated by approximately 13%, as compared to the intrinsic parameters. The relationship between the output power reduction factor and limited thermal conductance of TEG packaging was also derived. Approximately 25% of the maximum output power is lost because of the parasitic thermal resistance of the TE module used in the experiment.