TE generator test facility for low resistance single elements

A test facility for thermoelectric (TE) generator modules and graded TE elements has been developed. Reference blocks for the heat flow measurement are serially connected to the sample. Special constructive solutions prevent a disturbance of the heat flux distribution by radiation. Different thermal greases have been used to obtain a good thermal contact between sample and reference. For the characterisation of electrically loaded single element generators as well as graded TE elements a fine tuning of low resistive loads is required. A computer controllable resistive load has been built up for this purpose. A series of FeSi₂ generators has been manufactured and tested. Thermopower, resistance, thermal conductance, and efficiency have been measured for a hot side temperature up to 600°C, keeping the cold side near room temperature. After minor modification of the apparatus, the properties of graded model systems can be measured to draw a comparison with model calculations