Low-Frequency AC–DC Differences of a Series–Parallel Circuit of Thermal Converters

A series-parallel connected thermal converter (TC) arranged in an m × m matrix of a heater and an m
²
-series connected thermocouple are proposed to reduce low-frequency ac-dc differences. The electrical circuit theory on the proposed circuit suggests that the low-frequency ac-dc differences of m × m series-parallel connected TCs decrease in proportion to 1/m
²
, avoiding any degradation in the output voltage and a time-consuming measurement. A significant reduction of the low-frequency ac-dc differences by a factor of 10 for the proposed circuit is experimentally demonstrated with no decrease of the output voltage, which is consistent with the electrical circuit theory.