Modeling and verification of a thermoelectric energy scavenger

In this paper, a thermoelectric energy scavenger with one thermoelectric (TE) module is discussed. Its steady state mathematical model is established with the method of electro-thermal analogy. Equations of output voltage and electric power vs. load resistance are derived, and then used to simulate the scavenger performance. Furthermore, two thermoelectric modules are connected in series both thermally and electrically in order to enhance the performance. Simulation analyses indicate that, with a steady heat source and ambient temperature, the scavenger has the characteristics of a DC power, as long as it is not overloaded. In addition to TE module(s), thermal resistances of other parts in an energy scavenger have great influences on the scavenger performance. Series connection both thermally and electrically of two TE modules does enhance the performance of the TE energy scavenger as long as the thermal resistances of TE modules do not dominate in the whole thermal circuit. All conclusions derived from theoretical analysis and simulation have been verified with experiment results.