Multi-Stage Thermoelectric Coolers Current Optimization for Infrared Detectors Based on the SNOPT-Finite Element Method

At present, series power supply has been widely used in multi-stage thermoelectric coolers (TEC), however, the series power supply cannot fully utilize the full cooling capability of multi-stage TEC. In this paper, according to the actual working conditions of IR detector coolers, three multi-stage TEC models with different numbers of stages were established, and a new method of SNOPT-FEM coupled analysis was adopted to individually optimize the current of each stage. The method considers the synergistic influence of inter-stage thermoelectric effects, which makes the simulation results closer to reality and improves the model solution efficiency with the help of algorithms, which shortens the computation time by at least 46%. The results show that the cold side temperatures of 3-stage, 4-stage, and 5-stage thermoelectric coolers with separated and separated algorithmic power supply can be reduced by 7.95 K and 8.59 K, 8.20 K and 9.04 K and 8.37 K and 9.13 K, respectively, compared with the series power supply. The large cooling temperature difference under separated and separated algorithmic power supplies was achieved at the expense of more power consumption and lower COP compared with the series power supply. Therefore, high-power sources are required to meet the cooling needs of IR detectors in engineering applications. It is thus evident that the proposed method is favorable to promote the application of thermoelectric cooling in infrared detection.