Demonstrating Internal Characteristics for Thermoelectric Generator (TEG) Reliability

Thermocouple-based thermoelectric generators (TEGs) offer a promising pathway for converting waste heat into electrical power without moving parts. This study combines experimental characterization and MATLAB/Simulink modelling of Type E (chromel/constantan) and Type K (chromel/alumel) thermocouples configured in series and parallel topologies to quantify voltage, current, and power generation characteristics. An equivalent electrical circuit model, parameterized using NIST ITS-90 thermocouple coefficients and validated against laboratory measurements, demonstrates close agreement between simulation and experimental results. The quantitative comparison reveals that the proposed TEG model accurately predicts output voltages within 2% mean absolute percentage error and load voltages/currents within sub-millivolt and sub-milliampere root mean square error ranges. These findings validate the modeling methodology and provide practical insights for optimizing thermocouple-based TEG configurations in waste heat recovery applications.