Evaluation of thermal junction quality in thermoelectric assemblies using transient analysis technology

This paper describes the application of the transient analysis test method to evaluate the integrity of thermal junctions in a thermoelectric (TE) assembly. The quality of thermal junctions in assemblies was measured by creating a thermal gradient in the TE modules comprising an assembly and analyzing the decay of the residual Seebeck voltage. A study was made of various junction conditions that exist between the TE module and its heatsinks which are common to most assembly techniques. Poor thermal contacts were deliberately introduced such as insufficient thermal grease, inadequate compression and improper surface finishes in test assemblies in order to simulate typical assembly defects. A direct correlation between good and inadequate thermal junctions was established and illustrated through graphic test data evaluation.